2015-36-0090 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: Experimental study of combustion for mixtures of Ethanol and ignition improvers in a rapid compression machine
Autoria: FERNANDO ZEGARRA SANCHEZ
Resumo: Over the past decades, researchers from different countries that produce oil or not, have intensified their research in order to develop more efficient systems for the use of fossil resources. Great efforts are also being directed to the use and development of renewable energy sources. It is not unknown to the world that the main source of energy used in transport is the diesel oil, to be more economical and also more efficient. For this reason, various sectors of transport and fuel producers are developing new technologies in order to replace traditional fossil fuels with other renewable sources. Nowadays it is possible to find on the market engines that run on blends of diesel and other renewable fuels and also systems that work with mixtures of ethanol and other elements (additives) to improve autoignition (ignition improver). To be able to use ethanol in compression ignition (CI) engines, the main problem to be overcome is the poor flammability of the ethanol under compression ignition conditions such that diesel fuel is used. This problem is generally attributed to the high enthalpy of vaporization of alcohol and the need for higher autoignition temperatures when compared to diesel. The most commonly used techniques in trials with compression ignition engines, to correct this problem, are preheating the air in the intake manifold, or increasing the compression ratio, or the addition of an ignition improver for this fuel. The option to adapt the fuel to the engine, by increasing the quality of autoignition, is typically made through the use of additives. In this work, different tests were carried out in a rapid compression machine using ignition improvers for ethanol from the use of polyethylene glycol (PEG). Tests were conducted for different start of injection (SOI) instants of the mixture and different compression ratios. The results show the behavior of combustion for these different techniques for injecting fuel, with different concentrations of ignition improvers with compression ratios of 16: 1, 20: 1 and 25: 1.
2015-36-0095 || Ano de publicação: 2015
Categoria: Segurança
Título do Paper: ISSUES ABOUT THE ILLUMINATING SURFACE IN AUTOMOTIVE SIGNALING
Autoria: CARLOS ALBERTO LEITE DE MOURA
Resumo: This article discusses one aspect of great importance in vehicular signaling: the illuminating surface of automotive tail lamps. To the extent that we do not see the light, but only a surface or object illuminated, becomes valid the question about the minimum area that is necessary for the perception of light signals. With the advancement of vehicular signaling technologies, especially the increased efficiency of the new generations of light-emitting diodes (LED), there is the possibility of developing automotive lamps with increasingly smaller illuminating surfaces. This context gives rise to a problematic factor, enables the development of automotive tail lamps with high intensity but increasingly smaller lit areas. Consequently there is a possibility of tail lamps with more light intensity be less noticeable than others with less light intensity, just the appearance of the illuminated viewable area, as perceived by the human eye. By these assumptions, it’s timely to examine the constituent bases of an automotive lamp: available technologies and the legal and normative parameters that refer their functionality. Thus, the central question of this article is: how to develop stop lamps with small illuminating surface without compromising the safety of automotive signaling? What reinforces the importance of this question is the fact that the automotive tail lamps are designed to be seen, not being sufficient (for this development) only the existence of high-intensity light sources, but also the entire context in which the tail lamps are designed , in the development phases of a project, as the format devised by the designers, with their dimensions of functional (illuminating) area. The methodology used will consist in to confront the current stage of technologies with existing normative and legal references, seeking, by this way, to analyze if there are or there aren’t sufficient allowances for safe projects developments, with special attention to the question concerning the visual perception (automotive signaling focus).
2015-36-0099 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: UREA CRYSTALLIZATION LEVEL MEASUREMENT GENERATED IN NEW EXHAUST LINE CLASS DIESEL ENGINE THAT CAME AFTER CHANGING THE PROGRAM CONTROL OF AIR POLLUTION IN AUTOMOTIVE VEHICLES.
Autoria: RAFAEL MENGARDA
Resumo: This document aims to present a urea crystallization measurement method generated in the exhaust line of motor vehicles powered by diesel engines that meet the new legislation to Proconve P7 emissions. It also highlights the importance for appropriate selection of temperature and pressure sensors used during the measurement process of the quantities that are intertwined in this process. Presents results throughout the crystallization process generated over a 150 hour test cycle running on a plane. The results show that in this case there was a significant urea crystallization, however, despite being classified into an intermediate level, has no negative impact on engine efficiency. Since this crystallization is easily eliminated when the exhaust line exceeds the range of 350°C for a short period of time.
2015-36-0101 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: Reactivity Controlled Compression ignition (RCCI) for the Mixture of Diesel Fuel and Hydrous Ethanol in a Rapid Compression Machine.
Autoria: JUAN CARLOS VALDEZ LOAIZA
Resumo: The power generation, used to promote comfort, mobility and others continually grows. The demand for energy grows as much as the number of studies in this field. To solve this growing demand, efforts have been directed towards the development of new energy sources, preferably renewable, and better ways of energy conversion by increasing the processes efficiencies. A good example of this is the gradual change from conventional and highly inefficient vehicles to hybrids or purely electric ones. But even with gradual migration for more efficient energy use, we will continue depending on traditional fuels. Therefore, it is necessary to develop more efficient and less polluting ways to use these sources. Thus, this work aims at studying alternative ways of converting energy contained in fuels used in internal combustion engines. By the use of the combustion mode RCCI, two fluids with different auto-ignition characteristics are introduced into the combustion chamber at different times, with the purpose of burning the fuel with lower power auto-ignition. The amount of each fuel and start of injections (SOI) are parameters that strongly influence the combustion. The results show the parameters for the different techniques of injection of fuels with compression ratios of 16:1 and 20:1.
2015-36-0102 || Ano de publicação: 2015
Categoria: Ruídos e Vibrações (NVH)
Título do Paper: dynamic analysis of a half-shaft equipped with vibration absorber
Autoria: PAULO ESTEVES DE ALMEIDA SILVA
Resumo: The search for excellence in customer satisfaction has required an intensive engineering work aimed to reduce the influence of undesirable vibrational phenomena in the various subsystems of the vehicle. This study aims to examine the effects of vibration in the half-shafts, which are the elements of the vehicular transmission system responsible for transmitting the output torque of the differential to the wheels, identifying its sources and external interfaces and verifying the contention actions of vibrational phenomenon. For this, we used the computer simulation using the finite element method for analyzing the behavior of an equivalent system of the half-shaft equipped with a dynamic vibration absorber. A modal analysis was performed to determine the natural frequencies of the system and also an analysis of response to harmonic excitation, reproducing the conditions of bench tests performed for experimental determination of the same natural frequencies. Subsequently we present a calculation for determination of natural modes of vibration for a mass-spring system with two degrees of freedom equivalent to the half-shaft with absorber, and then a comparison is made between the natural frequencies calculated analytically by the approximate system and natural frequencies found according to the modal analysis performed using the finite element method.
2015-36-0104 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Airflow optimization w/ distinct intake valves designs by Numerical and Experimental Study in a 4-cylinder spark ignition engine
Autoria: FERNANDA PINHEIRO MARTINS
Resumo: Abstract This paper deals with the study of different design configurations for intake valves and valve seats on a current production cylinder head and their effect on airflow behavior and optimization. The analysis was performed trough a Design for Six-Sigma methodology (DFSS). The cases were simulated through computational fluid dynamics software and a prototype considering the best configuration was built and tested at flow bench laboratory. Correlation between simulation and experimental data was performed in order to validate the results for current, as well as, for future studies. The goal is to determine how geometric design variations on intake valve profiles and valve seats affect airflow. Finally, the best geometry evaluated was applied as input for a 1-D simulation comparing the new configuration with the current, and the gain in flow was correlated to engine performance. Keywords: flow bench, intake valve profile, cylinder head, airflow, computational fluid dynamic simulation
2015-36-0106 || Ano de publicação: 2015
Categoria: Ruídos e Vibrações (NVH)
Título do Paper: Numerical and experimental studies of a poroelastic material using the JCA model
Autoria: LUCAS FERNANDO COSER
Resumo: Poroelastic materials are commonly used in passive noise control due to their low cost and efficient acoustic absorption characteristics in the middle to high frequency range. They consist of a rigid and a fluid phase and are responsible for the dissipation mechanisms that attenuate the propagation of acoustic waves inside the material. The understanding of these phenomena and their translation into parameters existing in the mathematical models for poroelastic materials are of key importance in the design of optimized structures and when choosing the proper materials for each application. This work presents results on the validation of Johnson-Champoux-Allard (JCA) model of a melamine foam sample. The JCA model assumes a rigid frame. Finite element simulations of an impedance tube using the Virtual.Lab® software are validated by experiments. The measurements allow estimating the material properties, i.e., the parameters of the JCA model. Results show a good agreement between numerical and experimental data, which allows a better understanding of the use of the JCA model in complex simulations with poroelastic material layers for acoustic absorption purposes.
2015-36-0107 || Ano de publicação: 2015
Categoria: Ruídos e Vibrações (NVH)
Título do Paper: Experimental validation of simple acoustic sources using a 3D system for p-p intensimetry
Autoria: LUCAS FERNANDO COSER
Resumo: Simple and complex sound sources can be constructed using loudspeakers assembled on the surfaces of platonic solids such as the cube and the dodecahedron, whose implicit mathematical properties enable their application in acoustic radiation studies. By using special phase combinations of the electric signals applied to each loudspeaker, complex sound fields can be produced with their distinct spatial patterns. However, in many applications, simple sound sources like the dipole and the quadrupole are necessary in the investigation of acoustic phenomena. Their experimental validation is usually performed using a circular microphone array to measure the sound pressure field around the test object. This approach can be very complicated and poses many challenges in terms of test setup, execution and post-processing. Therefore there is a need of new experimental methods to characterize acoustic sources. This work presents the results from an alternative method using a 3D measurement system for sound intensity measurement based a p-p intensity probe. Known as SoundBrush®, it can measure in real time both the sound pressure and sound intensity fields in a very convenient way. For that purpose, a cubic speaker array was constructed to generate a dipole and a quadrupole source at different operating frequencies. The properties of their radiated sound fields were then determined and, although limited to 4 kHz and to the study of stationary phenomena, the technique proved to be very effective, not only for the verification of the sound pressure field predicted by the simulations, but also for the acoustic intensity field. Finally, the methodology can be extended to more complex sound sources such as radiating structures, of which the produced sound fields are usually very complicated to visualize, understand and validate.
2015-36-0108 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: CHARGE AIR COOLER INLET HOSE OPTMIZATION
Autoria: SAULO PALOMARES
Resumo: The hot side charge air cooler inlet hose’s primary function is to move the pressurized and heated air flow from the turbine to charge air cooler,which will cool the air before it gets back in the engine throttle body in order to allow enhanced combustion efficiency, engine performance and fuel economy, while also reduces exhaust emissions. Failure to the CAC hoses primary function may not only cause customer dissatisfaction due to lower performance, smoke and noise, but a major hose burst failure could result in sudden loss of power and consequently walk home condition.This paper will present an optimization in the CAC inlet hose from wrapped fabrication process with multilayered knitting with fluor silicone elastomer material to a less expensive material, singlelayered knniting and fabrication process able to attend all the validation requirements.
2015-36-0109 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Electrical Circuit Protection Design Through Computational Simulation
Autoria: JOAO FELICIO VENDRAMINI FERREIRA
Resumo: Circuit Protection Design Strategy Through Computational Simulation Abstract Automotive industry is already facing a growing in vehicular electrical load demand. New features as Electrical Power Steering, new infotainment devices, and loads as Heated Seats and Rear A/C blowers increase vehicle electrical power demand. Along with the increase in the electrical power system capacity to supply all vehicle loads, it is also necessary to implement adequate short-circuit protection for each load. In addition, industry need to be faster in product development and pursue cost reduction alternatives in order to achieve customer expectation. Electrical simulation using computational methods can support product development reducing hardware cost and implementing best alternatives for each proposal. This paper shows that it is possible to use Computer Aided Engineering (CAE) simulations in the vehicle electrical design. This strategy can be applied in an early stage of the project allowing cost reduction and contributing to improve product quality, since physical tests demand long time and man-hour effort to be performed. In addition are not feasible in earlier stages of the program since it requires hardware and prototypes. The focus of this paper is Circuit Protection Design Strategy using computational methods, which verifies that Circuit Protection Devices (CPD) perform adequately under short circuit failure modes. It also presents a Transient Stress Analysis (I2t) in fuses, which is an important requirement that must be evaluated during Circuit Protection Validation. I2t is a measure of the thermal energy stored in a fuse during a time varying current event. I2t Analysis is useful in situations in which a start-up current, inrush current, or a series of overload pulses is expected. It is also important to mention that this strategy also requires correlation with physical tests. Circuit Protection Design Strategy should have robust assessment before design release phase, in order to guarantee that it achieves the best optimized design to support product features and requirements, meeting cost expectation and avoiding later changes that usually have significant impact to the program.
2015-36-0112 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: INFLUENCE ANALYSIS OF WASHERS MATERIAL IN FATIGUE LIFE OF BOLTED JOINTS
Autoria: FERNANDO DE AZEVEDO SILVA
Resumo: The union of parts by using bolts is one of the most used methods. Several factors influence the reliability of these bolted joints, including the washer material. During the process of applying torque to the bolted joint, an elastic deformation occurs in the bolt and a plastic deformation in the washer while applying the external force. This plastic deformation which occurs in the washer causes a reduction of the elastic deformation of the bolt and, consequently, of the preload, and depending on the values of external loading and deformation of the washer occurs the separation of the pieces of the joint, causing overload in the bolt and a reduction in its fatigue life. The use of numerical simulation using the finite element method allows varying the load and geometry values of the model.
2015-36-0113 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: Accelerating Automotive EMC Tests – A Comparison Between Numerical Simulations and Experimental Data
Autoria: JULIANO FUJIOKA MOLOGNI
Resumo: It is well known that Electromagnetic Compatibility (EMC) and Electromagnetic Interference (EMI) is a significant concern for automakers due to the ever-increasing electronics content that are installed into vehicles and brought by passengers. Automotive EMC tests are expensive and requires complex infrastructure (an anechoic chamber and expensive test devices) and especially a final physical prototype of the vehicle. Numerical simulations is employed to virtually simulate EMC tests reducing time and cost, nevertheless, occasionally numerical results does not agree with measurement data. This paper presents a comparison between numerical simulation performed with ANSYS HFSS and experimental data of a radiated immunity test considering a GM Agile vehicle. Several changes are made to the numerical model highlighting the importance of considering several parts of the vehicle in order to achieve a good agreement between numerical simulation and experimental data.
2015-36-0120 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: hybrid Dynamic Analysis of Crankshaft-Crankcase for Off-Road Engine Application
Autoria: ALEXANDRE SCHALCH MENDES
Resumo: This work presents the results and methodology of a dynamic durability analysis considering the interaction between crankcase and crankshaft. The approach is based on a robust mathematical model that can couple the dynamic characteristics of the crankshaft and the crankcase, representing the actual interaction between both components. Dynamic loadings generated by the crankshaft are transferred to the crankcase through flexible 3D hydrodynamic bearings. This methodology is referred to hybrid simulation, which consists in the solution of the dynamics of an Elastic Multi-Body System (E-MBS) coupled with a subsequent Finite Element Analysis (FEA). For this study, it was considered an in-line 6-cylinder diesel engine used in off-road applications. The crankcase design must withstand higher loads due to new calibration targets stipulated for MAR-I emission regulations. The main objective for the block definition is to pursue design changes with minimal impact in current applications, utilization with high number of carry-over parts and cost saving. As results, the crankcase fatigue safety factors are presented showing the benefits of the adopted methodology, which enabled fulfilling the objectives of the project through small changes in the component. The crankshaft dynamics stresses and safety margins are also presented in this paper.
2015-36-0121 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: Development of a new titanium alloy for aerospace applications
Autoria: VINICIUS RODRIGUES HENRIQUES
Resumo: Titanium alloys are excellent choices for aerospace applications due to the unique combination of strength and physical properties, which is demanding the interest in the study of their properties and microstructure. The aerospace industry accounts for about 75 % of world production of titanium mainly based in Ti-6Al-4V. Despite this great potential, the high production costs have limited their use. This study proposes the replacement of Ti-6Al-4V alloy by the potential and promising Ti-4Al -2,5V-1,5Fe (ATI-425), which replaces part of the content of vanadium by iron, reducing the production costs, with equivalent performance and sometimes higher. Thus, this work aims to study the microstructural development of Ti-4Al-2,5V-1,5Fe produced by powder metallurgy (P/M) - a process with lower costs, easy to operate and with strict control of chemical composition, producing parts with complex geometries and near-net shape. Sintered samples were characterized for phase composition, microstructure and microhardness by X-ray diffraction, scanning electron microscopy and Vickers indentation, respectively. The influence of some process parameters on the final microstructure was also investigated in order to produce the alloy by P/M. The results demonstrated that the microstructural development and porosity are dependent on the dissolution of iron and vanadium particles.
2015-36-0127 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Fuel Heating for Hydrocarbon Emission Reduction
Autoria: PAULO CESAR F. GOMES
Resumo: The control of vehicular non-methane organic compounds emission (NMOG) has gained global importance due to its role in the formation of ozone and its contribution to “photochemical smog”. Some European countries and the USA already control NMOG emission, which are made of non-methane hydrocarbons (NMHC), aldehydes, ketones, and non-burned ethanol. In Brazil, the L6 stage of PROCONVE in force since 2013 limits the NMHC to 0.05 g/km for new passenger cars and it allows the deduction of the non-regulated unburned alcohol fraction. In order to fulfil future Legislations, the present work studied the influence of fuel heating with FlexStart® for reduction of NMHC emission. Aiming at that target, the FlexStart® system of a standard vehicle filled-up with ethanol was programmed to be active also at the temperature in which the emission tests were run. This study focused on Phase 1 of the FTP75 cycle, since almost 100% of the NMHC is emitted in this part of the test. Optimizations of the ECU calibration parameters had to be done because of the improvements on the fuel burning quality. This paper confirmed that fuel heating associated with ECU calibration optimization is an efficient solution to achieve the L6 limits of NMHC (0.05 g/km) without having to subtract the non-burned ethanol fraction.
2015-36-0132 || Ano de publicação: 2015
Categoria: Peças e Componentes
Título do Paper: Thermal analysis of brake disc system applied to light vehicles
Autoria: ZILDA DE CASTRO SILVEIRA
Resumo: In this work is presented a numerical termo-structural model applied to automotive disc brake. The coupling of the physical and mechanical phenomen during brake process must be investigated in order to provide reliability to vehicle and safety to the driver. In this way, the development of the analytic and numerical models support in the previsão of the behavior of the brake system, mainly of the disc-pad pair considering diferent situations of the brake process. In these process, parameters as: local temperature, friction coeficient, brake time, stress variation are fundamental to the improvement of the design of brakes and, thus during operational conditions. The results obtained indicated that the temperature gradient is significantly influenced by mass variation of the disc (expected condition). As a result, it can be seen that the maximum equivalent Mises stress increases by 33%, with of mass reduction of 25%. This design condition, also provides a satisfactory safety factor. This study indicates the mass reduction in the system must be made systematically in order of guarantee the integrity of components during the critical braking process. Key-words: brake disc; termal analysis; finite element; light vehicles, design of experiments; braking process.
2015-36-0136 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Fuel Consumption Reduction Based on the Optimization of the Vehicle Gear Shifting Strategy Considering New Gear Ratios
Autoria: JONY JAVORSKI ECKERT
Resumo: The gear shifting strategies strongly influence the vehicle fuel consumption because they change the powertrain inertia and the engine operation point. The literature normally presents gear shifting strategies based on the engine power and torque to improve the vehicle acceleration performance. Strategies based on fuel economy are hard to determine due to a large number of factors that influence the engine behavior such as the available transmission ratios, required acceleration and vehicle speed. In this paper it was evaluated the influence of the addition of more gear ratios in the vehicle gearbox, which initially contains five available gear ratios. For each proposed gearbox configuration, the gear shifting strategy was optimized through an algorithm developed to improve the engine fuel consumption in the Brazilian standard urban driving cycle NBR6601. The simulations were performed by means of co-simulation between the multibody dynamics software AdamsTM (where is located the model based on a conventional 1.0L vehicle) and Matlab/SimulinkTM (where is implemented the vehicle longitudinal dynamics equations). The optimization algorithm elaborated in MatlabTM utilizes previous simulations results, stored in a database, to compare them with the results obtained performing new strategies.
2015-36-0138 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: A geometrical model for lateral flexibility of tires
Autoria: RONALDO DE BREYNE SALVAGNI
Resumo: The existing tire models are basically of three kinds: essentially empirical (“magic formulas”), or mixed empirical/analytical, or extremely complex theoretical models almost useless in practical situations. The model here proposed does not require any empirical data, and presents a simple theoretical approach very suitable to use in project and analysis of real suspension systems. This paper presents a physical and mathematical model for the mechanical behavior of pneumatic car tires, in the particular case of lateral loading. It is a theoretical model, in the sense that it does not require any empirical data. It is based on the perfectly flexible and quasi-inextensible membrane theory. The next step will be to compare the calculated results from this model with measured data to validate this model.
2015-36-0142 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: Electric Vehicles Batteries Modeling Analysis Based on a Multiple Layered Perceptron Identification Approach
Autoria: ALEX PEREIRA FRANÇA
Resumo: A reliable battery state estimation management system in electric vehicles greatly depends on the validity and generalizability of battery models. This paper presents a Li-ion and Lead Acid batteries neural model. This model does not consider battery details, bringing universality, which is suitable for parameters estimation of all battery kinds. The final model proposes describe the dynamic contributions due to open-circuit voltage, polarization time constants, electro-chemical hysteresis, effects of temperature, state of charge and state of health. Also, this paper presents a comparative study between an accurate equivalent circuit model examining model complexity, model accuracy, adaptability and model robustness.
2015-36-0144 || Ano de publicação: 2015
Categoria: Carroceria e Estrutura
Título do Paper: Structural Engineering fundamentals applied on Body in White Design Development
Autoria: ALISSON ALVES SARMENTO
Resumo: Automotive Body in White development fundamentals This paper aims present information regarding Automotive Body in White development fundamentals, providing a link between physics fundamentals and real automotive development. An introduction about product development process will be shown in order to allow the reader comprehension about timeline decision process. A complete revision regarding applied loads, interface application, manufacturing requirements (DFA and DFM), studio requirements, safety and virtual/physical validation will be covered. The importance of sheet metal selection is a key role of Design Engineer to achieve cost, mass and performance targets. The result of this paper will allow a technical reader understand how engineers use engineering applications on body in white real design development.
2015-36-0145 || Ano de publicação: 2015
Categoria: Meio-Ambiente
Título do Paper: Comparison of CO2 emissions and energy consumption of an electric vehicle and a vehicle with an internal combustion engine
Autoria: ANA CAROLINA RODRIGUES TEIXEIRA
Resumo: This paper presents a comparison between an electric vehicle and a vehicle with an internal combustion engine regarding carbon dioxide (CO2) emissions and energy consumption, whether in electric or chemical form (contained in the fuel). For this analysis, the AVL Cruise software was used to simulate two similar vehicles, one electric and the other with an internal combustion engine. Some parameters adopted in the simulation were: flat, straight road, a 70 kg vehicle driver and driving cycle according to the U.S. FTP-75 standard. The CO2 emissions from the electric vehicle were calculated using the CO2 emission factors from electricity generation in Brazil in the year 2014. The results showed that the electric vehicle emits about 20 times less than a vehicle with an internal combustion engine, even with the high CO2 emission factors faced by the Brazilian electric sector in the period considered. With regard to energy consumption, the vehicle with internal combustion engine had a consumption of 0.6830 kWh/km and the electric vehicle 0.0951 kWh/km. Keywords: electric vehicle; emissions; carbono dioxide; energy; fuel consumption.
2015-36-0147 || Ano de publicação: 2015
Categoria: Metodologia de Projeto e Design
Título do Paper: Study of geometric parameters for validation and reduction in effort of the steering system of a vehicle FSAE.
Autoria: ANDRE TOGNOLLI
Resumo: This paper explores the method of modeling and validation the computational tools able to accurately replicate the dynamic behavior of a Formula SAE vehicle. Based on limitations in conducting physical tests, it is possible to mathematically predict the forces and momentum generated on the steering column of the vehicle, minimizing effort and improving driver comfort even before the component physically manufactured. The results in permanent state due technical instrumentations were used in the physical vehicles and compared with other proposals (skid Pad test). As the software simulating the same path, it was possible to adopt values of speed and wheel steering, allowing compare the dynamics of the vehicle, through the signals from other sensors installed in the data acquisition system, validating the behavior of the models presented in permanent state. Other aspects were studied to understand vehicle behavior concerning lateral stability and steering behavior. In order to improve the steering system, the axle sleeve was changed, resulting in driver’s less effort on handling. This proposal was compared to virtual models noting the efficiency of multibody models and was observed the decrease in an effort to turn the steering wheel.
2015-36-0151 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: standardized framework for monitoring and management of energy indexes
Autoria: RENATO ELY CASTRO
Resumo: This work describes the requirements for the definition, implementation, maintenance and improvement of energy management systems in the industrial environment with a systematic approach concerning continuous improvement routines for energy efficiency. For this purpose, it was proposed the establishment of a framework based on automation to implement monitoring, verification and management of energy resources compatible with a standardized energy management system, including requirements for energy use and consumption, in addition to monitoring, documentation, communication, project best practices, equipment acquisition, systems, processes and human resources involved in energy performance. The strategy of energy use analysis proposed in this work is based on the methodology of monitoring and targeting that consists of a systematic approach in the use of energy resources in order to achieve the best economic result through the permanent management of energy consumption. Furthermore, this work includes that system as a procedure in the planning phase of ISO50001 standard which establishes the concepts for energy management systems implementation. In order to aggregate all tools associated to this scenario, this paper proposes the use of a supervisory tool integrated to a real-time software (Soft-PLC) that runs the control application and a factory floor distributed system automation hardware in an IEC61131 compatible environment. The project of the control application of energy use was conducted using different programming languages defined in IEC to perform all the procedures of measurement, monitoring and management required by the system, including comparative analysis with the "best practices", use of innovative technologies, product and service approach, energy audit and compliance with regulatory milestones. The expected results of adopting an automation-based platform for energetic management include system flexibility, adaptability and usability. Besides, a project of automation in this scenario of open platform tends to introduce lower development and deployment costs.
2015-36-0154 || Ano de publicação: 2015
Categoria: Carroceria e Estrutura
Título do Paper: The usage of Finite Element Analysis on Weld Spots Optimization and its Potential Contribution for Production's Volume Increase
Autoria: LEONARDO CORITEAC
Resumo: Welding is the longest automotive manufacturing process in terms of time. Actually approximately 95% of a body structure joining is made by spot welding process. In this specific process, the panels are joined one against each other via pressure and an electric current released by the welding machine. Taking as benchmarking the body structure of vehicles made in Brazil at B segment, there are approximately 5000 weld spots in a body structure. Some case studies are demonstrating that using virtual CAE tools it is possible to reduce significant amount of weld spots without loss of function and body performance.
2015-36-0156 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Aerodynamic Shape Improvement for Driver Side View Mirror of Hatchback Vehicle using Adjoint Optimization Method
Autoria: FELIPE COSTA MAGAZONI
Resumo: Nowadays, one of the most important key role in vehicle development is the aerodynamic, which aims efficiency on fuel consumption and leads to a green technology. Several initiatives around the world are regulating emissions and efficiency of vehicles such as EURO for European Marketing and the INOVAR Project to be implemented in Brazil on 2017. Thus, this study intend to perform an optimization to minimize the drag force of hatchback vehicle. The main goal of this work is demonstrate the potential of optimization techniques to provide an aerodynamic shape improvement for the driver side outside rear view mirror of hatchback vehicle. The optimization solver used in this work is the Adjoint Solver, which makes shape sensitivity analysis and mesh/volume morphing. The study was conducted using CFD simulations to reduce the drag of current production hatchback vehicle previously validated and correlated in wind tunnel test. Firstly, the optimization solver is used to improve the surface of the view mirror to decrease its drag force. Results show drag decrease for the optimized surface of the view mirror. This work demonstrated the potential of optimization technique, which can be applied in early stages of projects and extended to optimize several surfaces of body vehicle.
2015-36-0158 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Windows Opening Influence on the Drag Coefficient of a Hatchback Vehicle
Autoria: FILIPE FABIAN BUSCARIOLO
Resumo: Aerodynamics plays a key role in nowadays vehicle development, aiming efficiency on fuel consumption, which leads to a green technology. Several initiatives around the world are regulating emissions and efficiency of vehicles such as EURO for European Marketing and the INOVAR Project to be implemented in Brazil on 2017. In order to meet requirements in terms of performance, especially on aerodynamics, automakers are focusing on aero-efficient exterior designs and also adding deflectors, covers, active spoilers and several other features to meet the drag coefficient. Usually, the aerodynamics properties of a vehicle are measured in both CFD simulations and wind tunnels, which provide controlled conditions for the test that could be easily reproduced. During the real operations conditions, external factors can affect the flow over the vehicle such as cross wind in open highways. The aerodynamic behavior of the vehicle can also be affected by the influence of the user such as by opening the windows in order to cool down the cabin, which is the main topic of this paper. In this work, 12 different window-opening combinations are presented and the drag values compared with a baseline model, considering fully closed windows. The study was conducted using CFD simulations of a current production hatchback vehicle, with two passenger inside and full interior cabin representation. Results show drag increment for all presented cases, compared with baseline configuration, which also implies in fuel consumption increase. Further studies on cabin cooling effects and passenger’s thermal comfort are conducted in order to complement this paper.
2015-36-0159 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Virtual Downhill Brake Cooling Evaluation Methodology
Autoria: JULIO CESAR LELIS ALVES
Resumo: Abstract Due to high costs and confidentiality involved on vehicle development, more and more physical processes and procedures are being replaced by computer simulation. Within the advances in CFD codes and HPC cluster size, giant clusters became available at low costs allowing virtual simulations that were not possible some years ago at reasonable costs and time. This work takes advantage of this evolution and presents a solid and consistent virtual method to evaluate the brake system heating process in a downhill procedure. This kind of work allows the developer simulate the procedure that shows how the brake system performs under downhill conditions and its influence in drag coefficient, and, evaluate the rotor (or drum) thermal behavior when this system is placed in new vehicles without having physical hardware. Besides full correlation between tests and simulations are still under development, the available virtual tests allow the developer to understand the phenomena and in which direction the engineer should go to minimize costs, time and even optimize system designs. Using the rotor virtual simulation CFD approach, better visualizations and understanding of heat transfer and airflow behavior became available and it is possible to simulate the BET (Brake Equilibrium Temperature) and the stopping distance. Results using this proposed methodology show similar tendency with physical downhill brake heating curve. The present paper provides a contribution to the growing trend of using simulations in the industry.
2015-36-0160 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Proposal of Static Margin Limit During Launch Phase for the VS-30 Orion Sounding Rocket
Autoria: ALEXANDRE GARCIA
Resumo: VS-30/Orion vehicle is a two-stage, unguided, rail launched sounding rocket, consisting basically of two solid propellant motors, payload and service system. Unguided rockets must be stable to fly the planned trajectory. At launch the velocity of the rocket is relatively low and, consequently, the wind has more influence on the trajectory. After the vehicle lives the launch rail it encounters a horizontal wind. In this event, known as "take off", the rocket is disturbed by the wind and opens the maximum angle of attack (AoA). The center of pressure (CP) moves forward as the AoA increases from zero and, depending on the velocity of the wind, the vehicle may become unstable. For each rocket, there is a corresponding range of AoA for which the vehicle remains stable. The maximum value within this range is the angle at which the center of pressure coincides with the center of gravity, situation that corresponds to the limit of stability of the vehicle. The objective of this study is to ascertain the minimum wind intensity that can produce a negative static margin during the take off phase and consequently produce instability of the vehicle. The knowledge of the wind intensity that could make the vehicle to reach its limit of stability is a very important information for flight safety and decision making.
2015-36-0164 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Studies on a usage of a limited slip differential without full locking features compared to open type differential and traction control in mid-size truck - drivers for strategic decision balancing technical performance and customer perception
Autoria: ALEXANDRE RODRIGUES PINHO
Resumo: The purpose of this Paper is to share the findings in mid-size trucks when they present a rear axle with limited slip differential (no locking feature) compared to another rear axle with open type differential and traction control. Vehicles were assembled with axles containing two configurations and submitted to specific maneuvers and different road conditions that explore the functionality of the differentials. Customer perception clinics were also conducted in order to capture their reaction testing vehicles with these features installed. Vehicle were also instrumented and monitored in order to clarify the rear axle performance. All results are shared with recommendations in order to drive marketing and technical decisions when defining vehicle configurations to be offered to the customers.
2015-36-0167 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Experimental study of the start process of internal combustion engines operating with flex technology
Autoria: GUSTAVO ABREU ARAUJO
Resumo: Flex engines were introduced to the Brazilian automotive market in early 2000s, and has caracteristically the possibility of using ethanol and gasoline in any proportion as fuel. Since ethanol has inferior evaporative characteristics compared to gasoline, when supplied predominantly with this fuel (more than 80%), Flex engines have difficulty to start their operation, effect that is even worse at temperatures below 20°C. To minimize this problem, automakers have developed auxiliaries systems for the start of engine, which have different influences in the starting time, so in the start quality of the customer`s point of view. This work is proposed to analyze the starting time of vehicles from different segments of the Brazilian automotive market, with different cold start systems and engine configurations, to define a abacus where the starting time is correlated with the engine start quality for Flex vehicles.
2015-36-0169 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: Experimental Study of the Influence of Ethanol Concentration and Temperature on Gum Formation during Prolonged Storage of Brazilian Gasoline-Ethanol Blends
Autoria: FLORIAN ALAIN YANNICK PRADELLE
Resumo: Gasoline is a volatile, inflammable mixture composed of olefinic, paraffinic, naphthenic and aromatic C4-12 hydrocarbons. Gasoline presents low contents of oxygenates and traces of sulfur, nitrogen and metals which introduce instability. In several countries, like Brazil, ethanol is used as an alternative fuel and as an octane improver. Nevertheless, hydrocarbons present in the fuel slowly react at room temperatures with atmospheric oxygen and with each other. This promotes changes in their physical–chemical characteristics. The process is observed throughout all the fuel production and use chain, increasing fuel density. These resinous, polymeric, insoluble and nonvolatile materials that are formed with high molar mass, commonly called gums, form deposits along the vehicle fuel system. Their accumulation can cause engine wear and have adverse effects on engine efficiency, performance and durability. The formation of gums in gasoline depends on the gasoline composition, absorbed oxygen content and storage conditions (temperature and aging period). The presence of ethanol in gasoline seems to have a dilution effect. The exact mechanisms are not fully known, but it is agreed that they involve a series of free radical chain processes. This work studied the influence of aging period, temperature and addition of aqueous ethanol concentration on Brazilian E20 gasoline-ethanol blend properties. Density, kinematic viscosity, induction period and washed gum content as well as water content were evaluated. It intended to determine critical conditions where the fuel does not meet the specifications required for engine use, using predictive mathematic models given by two Doehlert experimental designs with three factors.
2015-36-0170 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: Typical failure modes of compression coil springs made from tempered CrSi wire
Autoria: FÁBIO SANS PICININ
Resumo: Compression coil springs are some of the most common machine elements in mechanical engineering. They are robust and efficient components, whose design is well defined and followed by the manufacturers. While field failures are rare and usually brought from bad conditions of use, failures in test bench tend to occur more frequently. Not always a spring is designed for "infinite life" as it may not be the critical element of the project. By testing a component with a finite life, a failure is expected to occur after the designed durability, having the objective of this paper to list some common failure modes in a bench test of compression coil springs made from CrSi wire in tempered and shot peened condition. While much of the literature focuses on large defects that cause premature failures, this paper presents the failure modes of "healthy" springs, i. e without defects that drastically could reduce the designed durability of the component, with the aim of helping failure analyzes linked to project development and innovation.
2015-36-0171 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Methodology for the analysis of virtual deformation of flexible elements associated with the engine displacement.
Autoria: ANDRE TOGNOLLI
Resumo: Through computational dynamic simulations is possible to achieve high reliability index in the development of automotive components, thereby enabling the reduction of cost and time of a product development with considerable gain in quality. This work suggests the validation of a methodology for simulation, able to predict and quantify the best design for flexible components that are under the engine action. Known the difficulty in predicting non-linear mathematical relationship deformation under effect of forces and moments, was established a study based on experimental measurements where were used as input parameters to simulate the dynamic behavior of flexible components, in this case, coolant hoses. Using IPS (Industrial Path Solutions) software to build the model to be simulated, the mechanical and geometrical properties have been assigned to each component and its thermal deformation as well, with the aim of obtaining virtually the real deformations in stationary condition, causing with the virtual static model represents accurately the experimental model. Finally, was established a dynamic routine to the model, simulating the characteristic movements of the engine and transmission assembly, thus yielding the behavior of flexible elements in a given situation in order to verify the component meets the package requirements, avoiding undesired dynamics interference and early degradation of each component.
2015-36-0173 || Ano de publicação: 2015
Categoria: Carroceria e Estrutura
Título do Paper: Aluminum in Body White for the Brazilian Market
Autoria: MAURO CELSO DE PAULA MARCIAL
Resumo: Global automotive companies have heavily invested in the vehicle development in order to provide higher energy efficiency performance to meet the new regulations, and to obtain tax incentives offered by the INOVAR AUTO PROGRAM. One way to improve the vehicle energy efficiency is reducing it mass or apply an optimization. The Body in White (BIW) optimization can be achieved applying aluminum parts, considering the aluminum is a lighter material, and the BIW is responsible for a significant percentage of the total mass of a vehicle. The Brazilian market faces a great challenge, regarding the high vehicle production using aluminum parts. The main challenges are: raw materials suppliers to meet the potential demand, the connections between aluminum parts and metal parts, material cost, manufacturing cost, reparability, skilled specialists, etc. It is expected an increase by over 300% in the aluminum application in BIW’s by 2025. This paper will present the current Brazilian scenario, the impact on the OEM’s with the aluminum application and the pros and cons in its application. Keywords: Body-In-White; Aluminum; Sheet Metal; Brazilian Market.
2015-36-0174 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: IMPLEMENTATION AND TESTING OF MAGNETOMETER CALIBRATION ALGORITHMS FOR AUTONOMOUS NAVIGATION SYSTEMS APPLICATION
Autoria: JADER AMORIM
Resumo: The attitude of autonomous marine, land, air or space vehicles can be determined from the state estimation by means of mathematical tools such as Extended Kalman filter. In the process of calculation of this value, three-axis inertial and non-inertial sensors are used. From the knowledge of the orientation of the main axis, it is implemented the automatic control of the vehicle. The solid-state magnetometer is a non-inertial sensor with three axes that provides both the direction and the magnitude of the magnetic field vector which it is being submitted. However, measurements of the Earth`s magnetic field vector, obtained using the three-axis magnetometer, are not accurate. In the vehicle itself, the presence of ferrous materials creates disturbances in the Earth`s magnetic field, distorting the measured field. The accuracy of the magnetometer can be improved by means of various calibration methods, which, in summary, calculate the vector components of the systematic error, which can be modeled as a magnetic field that overlaps and distorts the actual terrestrial magnetic field. More than 90% of the measured geomagnetic field is generated in the earth`s outer core and can be described by mathematical models that serve as reference to some of the magnetometer calibration algorithms. The objectives are to study and implement calibration methods for the solid state magnetometer: a geometric method and the TwoStep algorithm; simulate the application of the algorithms in a vehicle; develop an electronic device and software for the computer algorithms testing. The methodology is based on numerical simulations as an alternative for the TwoStep algorithm tests, with the development of a database of the earth`s magnetic field along the trajectory of the vehicle; and construction of an experimental device containing an Arduino Mega 2560 platform and a solid-state magnetometer HMC5843, that allows various movements required for the magnetometer calibration. The calibration methods are fast and reach the desired results, with comparable estimates. However, the navigation system, the type of mission and especially the device or vehicle, will determine which magnetometer calibration method is most effective for each case. This does not exclude the possibility of using a combination of methods, according to the conditions of each mission.
2015-36-0180 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Application of catalyzed HC trap on A flex fuel vehicle
Autoria: CIRO LUIZ STEFANI FILHO
Resumo: The working principle of the Hydrocarbon (HC) trap has been tested and demonstrated for a wide range of applications. In the Brazilian automotive market, the flex fuel vehicles represents more than 84 % of 2013 domestic production. The sugar cane derived fuel is known in the automotive industry as E100. The local ethanol (ETOH) has a different specification than the ethanol composition from other countries, as to mention the 4.9 % of water content. There is a growing concern by the government about the increase of environmental pollution caused by the unburned ethanol during vehicle cold starts, since its combustion products like alcohols, aldehydes and ketones all have a potential for ozone formation. Because of this concern, a new legislation will be enforced in the near future to reduce the ETOH unburned emission. With the improvement of washcoat technologies and zeolite layer durability, one potential solution to address the cold start emissions is the use of an HC trap catalyst. The first objective of this work is to compare the emissions level of a system with HC trap catalyst over the baseline results in a flex fuel vehicle, compatible with E100. Another expected outcome of this paper is to measure the HC conversion efficiency variation over the converter lifetime requirement. The third objective is to confirm the potential to reduce PGM loading in the close coupled (CC) and to measure the trapping efficiency of the zeolite layer combined with different three-way catalysts (TWC).
2015-36-0181 || Ano de publicação: 2015
Categoria: Manufatura
Título do Paper: Make-or-Buy as a Competitive Decision Tool for Automotive Industries
Autoria: RENAN SARDIM
Resumo: Productivity is result of competitive processes and it is a major factor for nation’s and industry growth. For Brazilian automotive industry it is tied, among other factors, to permanent value stream analysis and reevaluation. Especially on emerging economies, companies needs to review its strategies taking into consideration the market dynamics, current market position and future vision. Based on the manufacturing configuration, it is necessary to review current activities and process, checking in details which manufacturing operations add value to the organization, from technical, financial and strategic perspective. The decision to Make or to Buy, is a process for choosing to maintain the processes and operations in house or to outsource them. This is a key factor for industries, and is recommended the adoption of a methodology to assist the evaluation process. This paper targets to support the analysis and decision for an outsourcing process in automotive industries, using decision matrix, financial models and managing its implementation effectively. This paper shows as a result, the application of this model in a case study in an automotive industry. Automotive Industry
2015-36-0184 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: Differences and Synergies of the Emissions Monitoring System (OBD) for Otto (PROCONVE L6) and Diesel (PROCONVE L6 / P7) Vehicles
Autoria: LEONARDO DE OLIVEIRA COSTA
Resumo: Due to the constant environmental preoccupation, application of increasingly sophisticated technologies for control of motor vehicle pollutants and necessity of monitoring of such systems, the Embedded Emissions Monitoring System (OBD) was implemented with the primary function of ensuring that the pollutant emissions levels stay within the homologation limits during the whole vehicle useful life. For this reason electronic systems (such as sensors, actuators and model-based functions) are increasingly being used for powertrain control, thereby increasing the complexity of such systems. As a consequence the software fine tuning is also becoming more complex leading to increase of costs during the product development phase. In this paper are presented theoretical and practical analysis of the OBD system for Otto (L6) and Diesel (L6 / P7) systems in order to evaluate the differences and identify possible synergies between both applications.
2015-36-0189 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: PREDICTION OF GASOLINES PERFORMANCE IN INTERNAL COMBUSTION ENGINES USING KRIGING METAMODELS
Autoria: ROGERIO NASCIMENTO DE CARVALHO
Resumo: Accurate simulation of fuel properties influence in internal combustion engines performance is a very complex approach and combines many physical and chemical concepts such as combustion phenomena, chemical kinetics, fluid dynamics, turbulence and thermodynamics. The right modelling of that is still a challenge and currently available software packages for engines simulation usually consider standard or surrogate fuels. The objective of this paper is the prediction of gasolines performance in internal combustion engines as an auxiliary tool in researches and developments of new fuels, reducing experimental timing and costs. It is proposed the use of kriging metamodels based on bench test results of a flexible fuel engine running with distinct blends of iso-octane, n-heptane, toluene and ethanol, to predict performance, energetic efficiency and pollutant emissions in function of fuels properties and operating conditions.
2015-36-0191 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Electric Vehicles – Energy Consumption and Range Tests using Multi-Cycle
Autoria: SERGIO WILLIAM BOTERO
Resumo: Electric vehicles are being marketed in several countries and, as required for conventional and hybrid vehicles, they also need specific technical standards to evaluate the autonomy. The first methods for autonomy evaluation were not easy to adapt to new cycles, also they were not practical and efficient. The first methods for evaluating energy consumption and range, named single cycle test, consisted of repeated runs of driving cycles until the complete exhaustion of the batteries charge. The uncertain nature of the single cycle test hindered the method practicality, compromised the tests repeatability and required a lot of time to complete the test. The situation becomes critical when considering the advances in batteries with greater autonomy. Therefore, a new procedure was developed by SAE and the methodology is described in J1634 standard. This new standard provides methods for obtaining range of urban road or any other cycle using a single assay, called multi-cycle test. This new method reduced the time needed for testing and enabled the inclusion of new cycles. Moreover, the results obtained with the new method were more repetitive due to the constant speed cycle addition in the middle and at the end of the cycle. This work reports the standard J1634 applicability for electric vehicle tests, it includes the results for a pure electric vehicle and comparisons with the results obtained with electric vehicle test using single cycle method. It, also, presents details of the automation development to perform the multiple cycle test.
2015-36-0195 || Ano de publicação: 2015
Categoria: Sistema de Transporte
Título do Paper: EVALUATION OF A REAL-WORLD DRIVING CYCLE AND ITS IMPACTS ON FUEL CONSUMPTION AND EMISSIONS
Autoria: VINICIUS RUCKERT ROSO
Resumo: In order to improve urban air quality and to meet legislation requirements, vehicular technology is constantly advancing. It focus on techniques that reduce both fuel consumption and emissions of greenhouse gases as well as harmful pollutant emissions. The technologies, however, have different impacts depending on the city, its traffic conditions and urban planning as well as other socioeconomic and cultural factors that affect the driving stile. Thus, standard drive cycles such as NEDC, FTP75 or others may not represent properly the actual condition and are being progressively replaced by real-world driving cycles. This paper aims to analyze different modes of transportation operating in real-world driving conditions in the city of Santa Maria, in southern Brazil, in respect to emissions and fuel consumption. Data of real-world driving cycles were acquired for individual and public motorized transport to feed computer models of several vehicles and technologies. Impacts of each were analyzed and discussed to suggest appropriate solutions for the city’s urban motorized mobility.
2015-36-0196 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: VEHICLE SPEED RECOVERY TEST METHODOLOGIES ON CHASSIS DYNAMOMETER AND THEIR CORRELATION WITH TRACK TEST RESULTS
Autoria: ANTONIO CARLOS SCARDINI VILLELA
Resumo: Fun to drive is one of the main driver’s wishes. Therefore, it is a relevant attribute in vehicles and fuels development. Vehicles performance depends, mainly, on ignition and fuel injection strategies adopted by their manufacturers. However, fuel characteristics may significantly influence acceleration and speed recovery results. Regarding fuel development, it is important to establish test methodologies, which minimize experimental uncertainties. So, it is possible to detect acceleration or speed recovery variation and relate it to fuel characteristics changes. An alternative to traditional track tests is to perform speed recovery tests on chassis dynamometer, where it is possible to mitigate the effect of some parameters which may significantly vary on track, such as, ambient temperature, ground irregularities and wind direction and speed. In this paper, chassis dynamometer speed recovery test methodologies are proposed and their results are compared to those obtained on track tests using the same vehicle and two gasolines, with different physicochemical properties. During chassis dynamometer tests, some vehicle instantaneous parameters, such as, speed, power and fuel consumption were acquired along speed recovery. So, it was possible to determine the causes of performance variation due to the fuels.
2015-36-0197 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: On the development of a Fully Automated numerical methodology to improve vehicle’s aerodynamics optimizing its external shape
Autoria: THIAGO LUIS ZOLET
Resumo: Car manufacturers have a growing interest in developing more efficient vehicles. New technologies have emerged in different areas, one of them is vehicle aerodynamics. The aerodynamic resistance, ie, the forces generated by the air in a vehicle, has considerable influence on fuel consumption. In this paper it´s presented a computational methodology using CFD (Computational Fluid Dynamics) and optimization tool to evaluate production vehicle and indicate possible ways to reduce its drag coefficient. Efforts are concentrated on modifying the geometry of the external design, a procedure whereby vehicle´s regions of interest are chosen to be valued on a pre-set geometric range parameters, arranging a DOE (Design of Experiments) that are evaluated virtually. In a fully automated procedure, changes are made to these parameters using morphing tools and then CFD calculations are performed. Softwares ANSA and Star-CCM + are respectively used. Results are then evaluated according to the statistical approach of DOE indicating which regions have higher sensitivities on the drag coefficient. Full automation of the process makes it cheaper and faster. Its results become a very important information for developing a more aerodynamic vehicle an so , improving fuel economy.
2015-36-0202 || Ano de publicação: 2015
Categoria: Qualidade, Confiabilidade e Durabilidade
Título do Paper: Warm start robustness improvement using the heated cold start system in flex fuel engines
Autoria: FERNANDO DE OLIVEIRA JUNIOR
Resumo: This paper presents a new ethanol content identification concept, with focus on flex fuel vehicles start ability robustness. The solution refers to the usage of cold start system based on heated fuel rail (normally used for low temperatures) in a preventive way like an ethanol sensor, ensuring a successful start attempt in specific conditions, even at high ambient temperatures. At most of flex fuel projects, the ethanol content calculation (or the percentage of ethanol in fuel) is done through the oxygen sensor (also called lambda sensor). Therefore the engine start strategy considers the fuel mixture determined in the previous vehicle operation. In situations when the “learning phase” is not successful during the operation cycle previous to start attempt, and also in combination with an extreme fuel exchange situation after tanking (previous to the last vehicle operation cycle), it may happen that the first start attempt is not successful. In this case the engine management strategy acts reactively to ensure a proper engine start and drivability until the correct ethanol content is calculated. The new concept heats the fuel in these specific conditions, using this addition fuel line ethanol content information to adjust the mixture parameters, ensuring the start ability. Thus, the engine management is not anymore reactive and can preventively act before the engine start, improving the flex fuel system robustness without the need of additional components.
2015-36-0205 || Ano de publicação: 2015
Categoria: Ergonomia
Título do Paper: Passenger vehicle driver`s lower limbs ergonomics through the development of biomechanical models
Autoria: HELOISA RODRIGUES LOURENÇO DA SILVA
Resumo: Vehicle ergonomics, more specifically driver ergonomics, has been the subject of interest in the automotive industry as a way to provide customers vehicles that have more than modern project, efficiency and competitive price. The driver ergonomics is related to the way the driver interacts with vehicle interior, particularly, with the seat, hand and foot controls, considering aspects such as ease of access, space, proper upper and lower limb motion and drivers comfort and fatigue. Regarding lower limbs, the driver’s comfort can be evaluated in terms of joint moments and muscle forces, which are influenced by the hip, knee and ankle joint angles, which in turn depend on the distances between the seat and pedal. Variations in seat to pedal horizontal or vertical distances will result in different angular positions and, consequently, different joint moments and muscle forces, which are associated to greater or lower muscular activations and greater or lower driver’s fatigue. The present work aims at allowing the analysis of the driver`s lower limbs ergonomics through the development of a biomechanical model which, by the use of driver and vehicle real parameters, results in seats adjustments related to more or less comfort. The study shows that the proposed model and framework can be successfully used to investigate driver’s ergonomics. Results show some agreement with experimental data but predicted most comfortable regions are characterized by more flexed joint configurations when compared to literature data. This indicates the necessity of future model improvements.
2015-36-0213 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Hybrid Combustion Model for Engine Analysis in Real Time
Autoria: ALYSSON FERNANDES TEIXEIRA
Resumo: The analysis of engine’s performance, gas emissions and combustion parameters is critical in the development of internal combustion engines. The combustion parameters are used as an important tool for the identification of the reasons which have provided gains or losses in engine performance due to the use of a new technology or a new fuel. The real-time analysis of these parameters allows detection of anomalies, such as knock, and provides important information to the process of engine’s map calibration. From the measurement of the in-cylinder pressure curve and the use of a one-zone combustion model is possible evaluate the heat release rate, mass burned fraction and average in-cylinder gas temperature. Aiming to expand the amount of information available in real-time, such as unburned and burned gases temperature and volume, radius and velocity of turbulent spherical flame and turbulence factor, this paper presents a hybrid combustion model, being composed by coupling a two-zone model to a one-zone model. Using the proposed model, a combustion analysis of the Ford Sigma 1.6L is presented. The tests realized showed that the proposed model has an excellent performance, since it promotes a better understanding of the combustion process in real-time and reduces the post-processing time of the combustion parameters.
2015-36-0214 || Ano de publicação: 2015
Categoria: Metodologia de Projeto e Design
Título do Paper: UML and Synchronous Languages Blended into Hybrid fUML to Model Hybrid Systems
Autoria: ALESSANDRO GERLINGER ROMERO
Resumo: The notion of a hybrid system is centered around a composition of discrete and continuous behaviors. Although the difficulty in modeling hybrid systems comes from the diversity of these systems, the most promising approach to mitigate this issue is developing expressive and precise modeling languages. Nevertheless, the developing of expressive and precise modeling languages does not necessarily mean the emergence of a new language, on the contrary, this paper discusses precise semantics for subsets of existent languages. Subsets of existent languages are defined since expressivity and precision usually conflict, e.g., the size and complexity of a language (related to expressivity) may have direct consequences on the size and complexity of its semantics (related to precision). Precision means a semantics defined according to a well established formal method, furthermore, recognizing the real-time nature of hybrid systems, the modeling language have to enable determinism, predictability and straightforward composition. In this paper, we introduce hybrid fUML that blends synchronous features for controlling discrete behaviors, and differential algebraic equations (DAEs) into the standardized fUML (foundational subset for executable UML models). Synchronous features focused on discrete behaviors come from synchronous languages, which have been established as a technology of choice for specifying, modeling and verifying real-time systems, e.g., Lustre that is the basis of SCADE (software critical application development environment). Continuous behaviors are modeled using DAEs described using a subset of Modelica concrete syntax. The subset of Modelica concrete syntax is selected in such a way that its semantics is defined by the standard mathematical semantics. Hybrid fUML is a modeling language defined to enable description and analysis of system views of hybrid systems. A case study considering the spring-mass-damper system was developed to evaluate the introduced language. This type of system addresses the control of structural vibrations (including aerospace structures) and it was modeled by a continuous spring-mass-damper plant and a discrete proportional controller. The main innovative contribution lies in the novel model of computation of hybrid fUML. The model of computation allows the synchronization of physical time at the environment and at the models, moreover, it enables determinism, predictability and straightforward composition of models of hybrid systems.
2015-36-0215 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: FLEX FUEL ENGINE - INFLUENCE OF FUEL COMPOSITION ON THE CA50 AT MAXIMUM BRAKE TORQUE CONDITION
Autoria: GUILHERME BASTOS MACHADO
Resumo: The automotive industry usually adopts the crankshaft angle between 8 ° and 10 ° after piston top dead center for the CA50 (crank angle of 50% of mass fraction burned) in order to set the maximum break torque spark timing calibration in Otto cycle engines. There are few studies of the influence of fuel composition, such as the ethanol content, on the CA50 at the maximum torque operating condition. The subject is relevant to the extent that the fuels used in the Brazilian domestic market are different from those usually adopted abroad. The Brazilian gasoline must contain, by law, a volumetric percentage between 18 and 25% of anhydrous ethanol in its composition and, currently, this level is set at 25%. The introduction of flex fuel vehicles in the domestic market in 2003, which now represent most of the new vehicles production in the Country, allowed the use of any blend of national gasoline and hydrous ethanol. This significantly expanded the range of fuel properties variation. This fuel flexibility influences the design, calibration and efficiency of internal combustion engines. The present work is a study to assess more information on the influence of different fuels on the CA50 at maximum break torque operating condition. This knowledge may help in researches related to the development of fuels, internal combustion engines and in the search for greater engine efficiencies, using different fuels.
2015-36-0217 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Virtual correlation in fuel consumption analysis
Autoria: THIAGO BARBOSA DE MEDEIROS ALVIM
Resumo: Fuel efficiency is an essential matter at commercial vehicle development. High fuel consumption of commercial vehicles has been considered synonymous with inefficiency or absence of available resources and budget to test more driveline configurations in different customer missions. The Brazilian market have a several request of mission profile, trailer configuration, load distribution, average speed, productivity and fuel economy target. Due to the increase of operational cost, customer expectation of profitability and market competition the company need create some different methodology to develop the best line up for each customer without impact in the program milestones and budget. The aim of this work is developing of methodology of analysis and correlation of data acquisition system used for measuring the speed and position of a moving vehicle (VBOX) with the vehicle VCM available data in CAN to create a virtual vehicle model with the real driver interface and target of productivity. The virtual vehicle model is processed in a software of dynamic analysis bases on Matlab / Simulink with possibilty to tuning engine torque and power, BSFC, transmission overall information, rear axle ratio, dynamic radius and mechanical efficiency and driver interfaces up shift ,donw shift, gear skipping, shift time and gas pedal position to evaluate the best commitment of line up for each customer mission.
2015-36-0219 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: Lightweight Materials for AutomoTIVE Applications: A Review
Autoria: DANIEL HABER
Resumo: Today, in order to optimize the resources usage and reduce the air pollution, the automobile industry is facing new challenges, with the necessity to improve engines fuel economy, enhance vehicles autonomy and reduce the CO2 emission. One of the solution, which is being much surveyed, is the car components weight reduction.There is a range of new materials that have been developed to attend the new weight standards. Together with lightweight these materials must also deliver acceptable mechanical properties, easy to manufacture and to assembly capability, good appearance, high durability, good cost-benefit relation and in some cases also acceptable impact energy absorption. This paper presents a review of some of the lightweight materials that are being applied in automobiles, like Carbon Fiber, Aluminium Alloy, Magnesium Alloy, Hybrid Material and Polymer Composites. The physical characteristics, applicability in automotive components, manufacturability and relative cost are shown for each material.
2015-36-0223 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: Heavy Duty Ethanol Engines – A Sustainable Approach for Transit Bus Fleets
Autoria: FABIO COELHO BARBOSA
Resumo: Compression Ignition – CI or Diesel engines are currently considered the most fuel efficient combustion based drivetrain, and, for this reason, it has been historically used as the backbone for heavy duty markets, including transit bus fleets. At the same time, CI engines fueled by traditional crude oil based diesel fuel are facing the growing challenge of meeting the increasing stringent emission standards, specially on particulates matter, nitrogen oxides and greenhouse gases emissions limits. Moreover, petroleum based transport fuels are constantly faced by strategic and security concerns, due to the concentration of the main currently known reserves in political unstable regions. As such, it is both environmentally and economically important to find alternatives for crude oil based diesel fuel to be used in the transportation sector. Liquid biofuels can have attractive features like high energy density and potentially low air pollutant emissions, depending on their feedstock and processing methods. Ethanol potentially can contribute to replacing oil derived transportation fuels and reduce greenhouse gas emissions. Particularly important is the second-generation ethanol technology, produced from cellulosic biomass – with its intrinsic higher efficiency and lower costs – on the way to be commercially viable. Heavy duty engines can be ran basically with neat ethanol (with some technical modifications in the fuel and/or engines) as well as blended with additives (to maintain the blend stability and avoid phase separation). Ethanol has been used in transit bus fleets for more than 25 years on Sweden, in the city of Stockholm, to address the reduction of the high concentration of pollutants in the city center. More recently, ethanol heavy duty engines have also been evaluated in the so called “Bioethanol for Sustainable Transport” - BEST Program, to demonstrate the environmental benefits, engine technical/performance features and regulatory issues of ethanol as an alternative to fossil based urban transport fuels in some world cities, including São Paulo, the Brazilian city with the largest fleet of transit buses, which has been testing ethanol buses in revenue service with promising preliminary operational results, albeit with increased operational costs. This work is supposed to give an overview of ethanol use in heavy duty engines, with a focus on fuel properties and production methods, engine technology, performance and emissions, as well as a snapshot on some of the current ethanol bus programs worldwide.
2015-36-0224 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: FRACTIONATION OF COAST DOWN MOTOR VEHICLE
Autoria: MARA NILZA ESTANISLAU REIS
Resumo: This work presents a methodology to identify the contribution of each part of each section of the car totaling the Coast Down of a vehicle in order to determine the loss of kinetic energy of a motor vehicle in a predetermined position by established standards by technical standards . The results obtained by the Coast Down Test is intended to define the fraction that each of the three (3 ) main groups responsible for the loss of kinetic energy of vehicles : aerodynamics, Rolling Resistance and resistive frictional forces influence the outcome of the test. Through the result of fractionation is possible to generate information about each vehicle, and comparative between vehicles of the same band, the variables that generate loss of kinetic energy, to thus invest in the development of the parcels that have greater earning potential . It is intended to verify the influence of the following quantities of vehicle aerodynamic resistive load , resistive load of tires , brakes resistive load , resistive load resistive power transmission and the rear axle. The methodology used to measure these quantities is to simulate a test for Coast Down suspended in an automotive vehicle lift . This development will focus on more efficient vehicles for the use of energy created by the internal combustion engine and so generate more efficient vehicles as fuel consumption , achieving achieving the goals of reducing the emission of pollutants defined by new environmental rules agreed between nations worldwide .
2015-36-0225 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: Analisys of methods for extraction of information on images with low-depth of field
Autoria: FABIO DE LUCA
Resumo: In order to make devices partially or completely autonomous, it is imperative nowadays to extract relevant information from the myriad of data available. In the last years, it has become very common to use images as signals of interest to propose feasible solution to this problem. Image recognition can be used with high accuracy rates when the object of interest or the environment are controlled or well known. However, in open urban spaces, for instance, where there are all sorts of visual artifacts and stimuli (information), the segmentation of the object of interest (foreground) from the rest of the image (background) is a challenging issue. One possible way to tackle this problem is to use low-depth of field images, which analogously to our visual perception highlight the object of interest from the rest of the image. In this work, some methods and algorithms for segmenting low-depth of field images are analyzed and compared, providing an updated and contextualized version of the state-of-the-art of this topic.
2015-36-0227 || Ano de publicação: 2015
Categoria: Meio-Ambiente
Título do Paper: Evaluation of Biogas Use in Transit Bus Fleets
Autoria: FABIO COELHO BARBOSA
Resumo: Current massive urbanization process concentrates high amounts of population and impose an increased demand on transport systems. In this context, transit bus system plays an important role, as the most dynamic and less capital intensive transit option available. At the same time, it is strongly dependant on fossil fuels, predominantly diesel fuel, with its intrinsic polluting and greenhouse (climate change) effects. This has boosted research and investments for alternative and renewable fuels. One solution currently receiving widespread recognition is biogas use in transit bus fleets, as it allows the use of a renewable fuel, made from substrates derived basically from waste and sewage that otherwise would produce methane released to the atmosphere. Biogas contain basically methane, carbon dioxide, trace amounts of hydrogen sulfides and water, and to be used as engine fuel need to be upgraded, which means increasing the methane content up to 97% and removing water and other gases, when its composition becomes similar to fossil natural gas. From a technological perspective, biogas engines are generally spark ignited – SI and can be used in both lean burn (diesel derived) and stoichiometric (SI derived) combustion concept, each one with its own strengths and weakness related to efficiency, thermal loads and cleanness (emission potential). The most suitable technology will depend basically on the emission targets to be achieved. Investment costs with biogas buses are generally higher, while operational costs use to be lower than baseline diesel buses, with the net value dependant on the size of the fleet relative to the installed infrastructure (bus garage, distribution, storage and filling system) as well as the cost of biogas production and engine maintenance. This paper is supposed to give an overview of biogas potential as a renewable fuel, its potential production chains, a technological heavy duty gas engine roadmap as well as of an alternative fuel cost analysis.
2015-36-0228 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: scenarios of total cost of ownership for corporate fleet Electric vehicles
Autoria: MARCOS DE CARVALHO MARQUES
Resumo: This paper presents an analysis of the total cost of ownership (TCO) of five small utility electric vehicles (Renault Kangoos) and two passenger cars (Renault Zoes), used in logistics and operational activities of three companies, as part of a CPFL Energia R&D project, which is building a Living Lab at Campinas city metropolitan area. The analysis compares the TCO of the electric vehicles (EVs) and similar internal combustion. The scenarios (current and future) consider periods of five years and vary according to: use intensity; costs of acquisition and use; residual value. Acquisition costs were broken down according to the chain of applicable taxes. Scheduled maintenance costs, consumption (electricity and fuel) and annual tax were considered. For EVs, it includes battery autonomy and lifecycles. The project data has been obtained on daily basis from the vehicles use measurements. The Kangoos´s data have been collected from 12/26/2013 to 01/15/2015, but for Zoes, has started just recently. Several information have been collected and processed, creating daily records of: Energy recharges accounting: consumption in kWh, average consumption in kWh / 100km, recharge time, start and end time. Travel daily journeys of each VE: distance traveled, mode of use (economic/normal), autonomy and remaining charge state of the battery, load weight, external temperature, average speed, amount of stops in a journey and use of air conditioning indication. Besides daily records, some consolidated information about each VE and company has been calculated, such as total distance traveled (km), energy consumption (kWh), amount spent with energy consumed (R$), expense with fuel consumption (R$). Project consolidated indicators has also been calculated. Graphical results are provided, among them: i) TCO evolution versus kilometer of use, with or without residual value; ii) TCO decomposition (acquisition cost without taxes, taxes on the acquisition, annual use taxes, battery replacement, residual value, scheduled maintenance). The main finding of the TCO comparative analysis made is about the economic infeasibility of using electrical Kangoos for corporate use, in a five-years range, even though their spending on propulsion (electricity) and maintenance are significantly lower. The methods that have been applied to this study have been proved appropriate and advantageous, mainly because the developed controls has allowed proper experimentation of the object of analysis, in real operating conditions. Future simulations based on critical variables of this model might support coming regulation propositions regarding recharging infrastructure in Brazil. The developed TCO model is under improvement in order to include the analysis for the ZOE model. This additional analysis will be relevant because this other category of EV does not include the IPI tax exemption and have a higher penetration in the domestic market. In addition, in the future, the model could evolve in order to address the impact of new EVs recharge methods that include: i) fees based on consumption or time thresholds; ii) smart charging (user/EV/utility control); iii) two-way recharge systems (V2G and V2H).
2015-36-0231 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Inclusion of the displacement variable on the damper modeling in multibody environment.
Autoria: RAFAEL TEDIM TERRA
Resumo: The multibody computational simulation is typically used to verify the vehicle dynamic behavior. In this environment the shock absorber damping curve is commonly described with a curve considering the Force and the speed that are acting on the shock absorber F=f(v). However in the real world the damping curves (F=f(v)), changes during the shock absorber travel. In this case is natural to include the displacement variable in the damping modeling making the damping force function of the speed and the displacement F=f(v,x). This study will compare how this consideration affects the simulation results and what kind of event is relevant to adopt one of the studied models types.
2015-36-0232 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: avaliação da influência da espessura da parede de cilindros de blocos de motor a combustão interna na microestrutura do ferro fundido cinzento e vermicular
Autoria: JORGE LUIZ TONELLA JUNIOR
Resumo: O presente artigo avaliou a influência que a espessura da parede dos cilindros, de bloco de motor de combustão A1:BD63 tem na microestrutura do ferro fundido cinzento e vermicular, ambos tendo como grande aplicação blocos de motores de combustão interna. A diferença na forma como a grafita se apresenta em cada variedade de ferro impacta nas propriedades mecânica dos materiais, sabe-se que devido a morfologia do ferro vermicular, este apresenta maior resistência a tração e módulo de elasticidade superior ao ferro cinzento. O principal objetivo do artigo é o estudo da influência da espessura Duas amostras, para cada material, foram retiradas da face de fogo de um mesmo cilindro do bloco – em quadrantes que apresentam espessuras distintas. Focou-se na avaliação quantitativa da grafita através de parâmetros de morfologia e de distribuição para duas espessuras de ferro fundido cinzento e vermicular. As amostras foram embutidas em baquelite, lixadas e polidas. As imagens foram feitas em microscópio óptico, sem ataque químico, e com o auxílio do programa ImagePro obteve-se os parâmetros quantitativos. Os materiais apresentaram microestruturas clássicas. Entretanto, constatou-se que a espessura da parede do cilindro tem grande influência na microestrutura. Para ambos os materiais, a grafita apresentou-se com menor tamanho para a menor espessura e com redução do percentual de área nas imagens. Mudanças de forma também foram verificadas. Contudo, não se notou variação na distribuição das grafitas para os materiais, e condições, avaliados. Palavras-chave: Ferro fundido cinzento; Ferro fundido vermicular; Grafita; Morfologia, Distribuição.
2015-36-0234 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Torque-speed-temperature relationship in grease lubricated angular contact ball bearings
Autoria: LEVI NASCIMENTO DA SILVA
Resumo: High friction often involves high wear and power loss. The speed-temperature-dependence of grease lubricated angular contact ball bearings showed a variety of effects. The test apparatus is an axially-loaded angular contact ball bearing instrumented to measure the frictional torque as well as the transient temperature of the raceway. Effects of friction torque were examined at different speeds, operating temperatures and greases. Torque measurements and transient temperatures were compared for each grease, depending on the operating conditions. After experimental results, the grease formulation under different operation temperatures and different speeds showed significant influence on starting and rotating torques. Moreover the torque showed significant increase during the angular acceleration phase and decreased rapidly after the speed stabilization for all investigated greases.
2015-36-0238 || Ano de publicação: 2015
Categoria: Manufatura
Título do Paper: Study of the Deep Drawing Process Through Theoretical Calculation and Practical Tests
Autoria: EVANDRO BERTOLDI
Resumo: Abstract: Manufacturing is defined by the transformation of a material in primitive state into a finished product. The purpose of manufacturing techniques is the production of geometrically defined objects and certain properties, through different processes. The manufacturing technique to be studied is about deep drawing, in which allows the forming of a flat plate into a hollow glass, using a tool activated by movement and strength of a press by tension and compression efforts. This tool is composed of a pricker, a matrix and a flat-press. The tests were developed according to the regulation DIN 5080, in which the process is described as deep drawing. The forming process is labeled by the regulation DIN 8582 by conformation requesting tension-compression in room temperature. Deep drawing tests were made with flat-press and without it to verify the difference obtaining the piece after the process, evaluating the suitability of this process to the stamping operation. Tests were made from devices coupled to an equipment that transfers the strength, in other words it is pushed into the matrix. It was verified that the strength numbers found in the theoretical calculation were different from the ones found in the tests due the variation in the material and process properties. Key words: Forming Process, Deep Drawing Practical Test, Deep Drawing Theoretical Calculation, With Flat-Press, Without Flat-Press.
2015-36-0240 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Heavy Duty Valves with Enhanced Performance through Nitriding Treatment
Autoria: PEDRO MARTÍN LERMAN
Resumo: Heavy Duty Valves with Enhanced Performance through Nitriding Treatment Nitriding is a well-known treatment in many engine components. In valves, it is very common on light vehicle applications. For heavy duty applications, its use has been restricted due to considerations on temperature and structural resistance. However, it is known to be a very interesting concept regarding tribology, especially wear resistance, with a suitable compromise on cost. Due to the continuous increase of engine loads to attend different emission legislations, wear resistance became a key issue for valves. MAHLE developed a nitriding treatment to be applied on Heavy Duty valves presenting superior wear resistance and suitable structural resistance. Deep product validation is presented through rig and engine tests. Not less important is the introduction of gas nitriding as an environmentally friendly process in replacement of the traditional and almost unique technique to proper nitride valve alloys, salt bath nitriding. Gas nitriding will assure the same valve performance with the advantage of employing a lower nitriding temperature that would assure a higher tip end and seat hardness combined with lower distortions.
2015-36-0242 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Structural Integrity Evaluation of Plastic Welding (Heat Stake) Tower in Door Trim Panels of Vehicles Using Finite Element Method
Autoria: TIAGO SARTOR
Resumo: Door trims are ones of the most important parts among the interior finish of a vehicle, which reduce external noises, normally have objects storage and present ergonomic concepts providing comfort and improving the internal vehicle appearance. Those parts also have structural function, such as protect the occupants of the door internal mechanisms, helping the energy absorption in a lateral crash, resisting to the misuse conditions and aim assembling the handles and knobs. Therefore, these trims, usually made of polymeric materials, have to present good structural integrity, so the attachments of all components need to be performed appropriately. The connections between door trim parts can be made through clips, bolts, interference fittings or by welding tubular plastic towers (Heat Stakes), being the last ones most used due to low cost, high productivity and good retention between components. However, they must to be distributed properly and present appropriate sizes, in order to support loads during the usage. A disruption of a Heat Stake inside the door trim became it more flexible, generate noise, gaps, transmit the feeling of fragility and in an extremely situation loses the completely function. Therefore, aiming a robust design is necessary to have Heat Stakes positioned to ensure uniform effort/load distribution, without any weld overloaded or without any load (unnecessary). One of the main tools currently used during the development of structural components, allowing the determination of possible field complains, is the numerical simulation by finite element method, which combined with physical tests becomes an economically advantageous and efficient tool, enabling the prediction of failures in a reliable way. Through structural simulations it is possible determine which loads the Heat Stakes are submitted during different usage conditions, that can be compared with experimental results (statistically treated) indicating the maximum load which Heat Stake welded in the right way, resist for each polymeric material combination. So, through this methodology, is possible evaluate the better position to locate Heat Stakes and optimize the distribution, creating a product with quality and reliable, which meets the satisfaction levels required by customers.
2015-36-0245 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Study of Turbocharger high frequency Whistle Noise on prototype parts during development
Autoria: GUILHERME AUGUSTO LOPES DA SILVA
Resumo: Modern customer and legislation requirements have led to a high demand for energy efficient low pollutant engines. Such efficiency is commonly achieved through the deployment of turbochargers, in both Diesel and Otto engines. This strategy, replacing high displacement engines is a tendency commonly designated as downsizing. This allows higher power outputs, increased energy efficiency and lower emissions allied with lower weight on the vehicle’s power pack. Those turbocharger units consists basically of a compressor connected by a solid shaft to a turbine, which is propelled by the exhaust gases in order to compress (boost) the intake charge air to the engine, increasing pressure in the system. The turbocharger system is commonly a source for synchronous/sub synchronous noises, as well as compressor or turbine related NVH issues, which must be mitigated in order to fulfill customers’ expectations. Subjectively, a high frequency whistle noise was audible in the cabin for an entry-level vehicle cabin during parking maneuver – throttle “blips” – in a low displacement 4-cylinder diesel engine during design validation phase. Objective noise measurement confirmed the issue was not unbalance related. A detailed investigation was carried out to identify the source of the high frequency whistle. The present work shows the study performed to determine if the noise was related to component design itself, prototype manufacturing or instrumentation interaction with the system. The first section briefly describes the turbocharger system and aspects. The second part describes the root-cause investigation and analysis, with suggested corrective action. The third section shows the corrective action evaluation and derived lessons learned from the process.
2015-36-0262 || Ano de publicação: 2015
Categoria: Gestão e Desenvolvimento de Produtos
Título do Paper: life-Cycle cost ANALYSIS Applied to Urban Bus Chassis
Autoria: FREDERICO F.DE C. MATOS
Resumo: Maintainability can be understood as a set of design parameters that provide the ability of an item to be maintained. It can also be defined as the characteristics of maintenance because the capacity of an item to be maintained depends on the quality of the user`s management to operate and maintain. The relationship between the design and the quality of management will determine the level of efficiency of the vehicle regarding parameters related to time required for repairs and preventions, cost and associated resources and the good domain about failures. Blanchard et all. (1995) in the book Maintainability, the Key to Effective Serviceability and Maintenance Management, indicates the factors that must be evaluated to characterize equipment maintainability, which are: availability, reliability, time associated with maintenance, dependability, human, logistical support, economic and effectiveness. Among the economic factors, he indicates the need to assess the cost of the equipment throughout its life-cycle from the initial phases of operation until the disposition. This parameter maintains a close relationship with a continuing issue in fleet companies, what make and model of vehicle provides the best operating efficiency? The question makes emphasis due to the frequent renewal associated with the significant variation of operating conditions imposed on vehicles, causing high variability in the results for the same model, which makes the answer difficult. For manufacturers, knowing the expected profile of life-cycle cost would support the implementation of changes in the design and after-sales services, generating a solid process of continuous improvement based on the maintainability characteristics of the equipments. In order to answer that question, this article presents estimates of the maintenance cost along the life-cycle applied to urban bus fleets. The results were obtained from analysis of 1957 vehicles in 12 companies of Public Transport System located in Salvador, Bahia, Brazil, during the year of 2013. The main objective was to evaluate the competitiveness between companies and develop a tool to estimate the maintenance goals (considering the composition and age of the fleet) and project the total life-cycle cost expected for the assets. The study also proved to be a consistent basis for critical analysis of the equipment maintainability (the cost factor) presenting itself as a tool to associate the vehicle design to quality of maintenance and operation management. It parameterized the cost evolution of the most affected variables by aging (the consumption of parts, components reconditioning services and lubricants), plotted by stages between 0 to 700,000km. For all the analysis, the data was deployed in 08 vehicular functions (motor, transmission, brakes, steering, suspension, electricity, air system and axis). The results presented compare the performance of two similar chassis models, to figure out the differences between results imposed by design, and between fleet companies, to figure out the differences related to management quality. In both projections, significant opportunities for improvements in the project and asset utilization were observed, configured by the evolution of data dispersion with the mileage. Therefore, the study presents a methodology for assessing the life-cycle cost in fleets. Therefore setting up as an analytical tool able to parameterize the cost factor on maintainability of fleets and establishing benchmarks for improvement of design characteristics and the vehicles utilization.
2015-36-0263 || Ano de publicação: 2015
Categoria: Segurança
Título do Paper: DRIVER RESTRAINT SYSTEM OPTIMIZATION FOR VEHICLE FRONTAL IMPACT
Autoria: ANDERSON DE LIMA
Resumo: In 2010, the UN General Assembly proclaimed the period 2011–2020 as the Decade of Action for Road Safety, with a goal to stabilize and then reduce the forecast level of road traffic fatalities around the world. Road traffic accidents are the 8th cause of death in Brazil, according to World Health Rankings. There are few studies around the world with respect to cost due to traffic accidents, however a study performed in 2011 estimates that were spent R$ 44,6 billion in Brazil. So, the recent Brazilian regulations updates have enforced the automakers to develop vehicles safer to passengers and pedestrians. These regulations focus on prevent, reduce or minimize the traumas and injuries caused by different types of vehicular accidents. The present work was developed to optimize the driver restraint system, while focusing on minimizing the trauma during a vehicle frontal impact. The driver restraint system was optimized considering the complex interaction between the ATD and the different components that assemble the restraint system, like airbag, safety belts with/without pretensioners, seatbelt load limiting devices and steering column stroke. The numerical computational simulations were performed based on Design of Experiments (DOE), which is a powerful tool that allows for multiple input factors to be manipulated determining their effect on a desired output. The numerical computational model created was initially correlated with a physical test, and then 36 numerical simulations were performed in order to create the optimization matrix. The optimized parameters provided by the analysis of the DOE orthogonal matrix were simulated and showed a significant reduction at probability of injuries due to vehicle frontal impact. The computational numerical optimization tool helped to reduce the cost and time development of a safer vehicle that satisfies the current Brazilian regulations, focusing on driver performance. The results presented excellent correlation and the goals of the optimization were achieved showing that this tool is reliable and helpful for current and future developments.
2015-36-0267 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Experimental methodology and numerical simulation of intake valves discharge coefficients for a single cylinder research engine
Autoria: ROBERTO BERLINI RODRIGUES DA COSTA
Resumo: The design and development of highly efficient internal combustion engines require a thorough investigation of the fluid dynamic processes. This paper presents the experimentally determination and computational fluid dynamics simulations of the intake valves discharge coefficients of a four valve spark ignition single cylinder research engine. The mass flow rate and air pressure were measured directly in the intake port for six different values of valve lift (4.68; 6.16; 7.48; 8.62; 9.46; and 10.49mm). The theoretical mass flow rates were obtained based on considerations of subsonic flow. Simulations were carried using the Star CCM+ commercial code. Mesh independence studies, using the velocity fields as monitors, have been made for reliability of the simulations. As a result, a methodology was successfully implemented to obtain the discharge coefficients experimentally and the simulations were validated with a maximum deviation of 6.62%.
2015-36-0269 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: E100 stratified lean combustion analysis in a wall-air guided type GDI optical engine
Autoria: ROBERTO BERLINI RODRIGUES DA COSTA
Resumo: Gasoline direct injection (GDI) engines have very attractive potential for improving fuel economy and exhaust emissions, specially disadvantages of increased fuel consumption at part load. In this research, a study has been made on the investigations of stratified lean combustion in a wall-air guided type spark-ignition single cylinder optical research engine. Experiments were conducted at constant load (NIMEP 3 bar) using ethanol as fuel, for a wide range of injection, ignition and mixture formation parameters. Engine efficiency and combustion stability were evaluated at each excess air ratio. Optical visualization illustrated the spray behavior and flame propagation. Specific fuel consumption improvement was achieved with lean burn mixtures. Thus, combustion analysis data based on in-cylinder pressure measurement provide useful data for ethanol GDI engine development.
2015-36-0270 || Ano de publicação: 2015
Categoria: Segurança
Título do Paper: Fuzzy Shared Semi-Autonomous Control System For Military Vehicles
Autoria: HEBERT AZEVEDO SÁ
Resumo: Semi-autonomous control systems applied to automobiles are Advanced Driver Assistance Systems (ADAS) that have gained importance from similar devices with applications in robotics. The control sharing between humans and automatic controllers is the main characteristic of these systems, and can be accomplished through various different manners. However, the use of Artificial Intelligence techniques for this purpose remains unexplored. In this paper we propose the design of a semi-autonomous control system applied to military vehicles through the use of Fuzzy Inference Systems for the definition of the controller intervention level. Simulations of a vehicle being operated in highly dangerous situations, represented by the existence of hostile military threats or by unexpected maneuvers that could put the stability of the car at risk were performed. The control system’s level of intervention during the simulations was observed, and we could realize the increase of this variable according to the level of threat that the car was exposed to. The application of the proposed system results in safer operation of the vehicle, which shall be controlled with greater influence of the automatic controller when in greater danger. We present a critical analysis of these results and new directions for the future of this work.
2015-36-0271 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Vehicle-to-vehicle communication using AppLink
Autoria: ALEXANDRE MAGNO MASCARENHAS LOPES RIBEIRO COSTA
Resumo: With the increasing number of cars on the street, the exchange of information between those cars becomes essential to improve the driving skills of each driver, resulting in a safer, intelligent and more dynamic traffic. The task now is to make it accessible for everyone. One possible and cheap way to solve this issue is to seek possibilities on free technologies within market trends. Using the smartphone platforms, which holds a high level of embedded technologies, becoming a global communication device even to interpersonal and to social networks, and AppLink Development Kit for Ford vehicles, this paper will cover aspects about the integration of the kit to an database application based on the cloud, enabling real-time interaction between two cars. Making possible to a driver have access to information and current status of other cars to aid ones life on heavy traffic. AppLink library is available for free download, and integrating it with a database application, shall allow driver have to access a whole variety of information such as tire pressure, temperature, speed or GPS, easily and safely through visual or by voice. The vehicles can have access to average speed on different roads, share driving information’s as average consumption per distance to similar cars (same platform and engine), share your location and status to specific users, creating a network targeted to the transfer important information to aid public mobility policies. Vehicle-to-vehicle communication seen as an technology of the future, can be done using today’s technology. And even customers of entry level vehicles can already use it.
2015-36-0275 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Analysis of a Formula SAE Vehicle Suspension: Chassis Tuning
Autoria: ADRIANO GONCALVES SCHOMMER
Resumo: In this paper, a double-wishbone suspension design of a Formula SAE vehicle is discussed. The influence of geometric and kinematic parameters are analyzed to quantify how they change the vehicle dynamics behavior. This study aims to point out different chassis set ups to improve the overall performance of the prototype in the Formula SAE dynamics events, for instance Acceleration, Skid Pad, Autocross and Endurance. A full-vehicle model was designed in the software IPG Carmaker where vehicle stability, lateral acceleration and yaw rate were investigated in a skid pad and step steering input maneuvers. Torsional stiffness of the space frame chassis and aerodynamics effects were considered in the model even though they were not treated as a tuning parameter. To enhance simulation results, the tire was modeled in the software MATLAB where Pacejka’s Magic Formula was used based on data measured by Calspan Tire Research Facility through a Formula SAE Test Tire Consortium. Roll stiffness, tire pressure, toe and camber showed up as major tuning tools to attempt during the competition.
2015-36-0277 || Ano de publicação: 2015
Categoria: Ruídos e Vibrações (NVH)
Título do Paper: Acoustic Development differences between theoretical And Experimental Process for Automotive Exhaust System
Autoria: YURI FERNANDES DOS SANTOS
Resumo: Acoustic development process are important for automotive industries, therefore, it is relevant to study and compare theoretical, numerical and experimental results. The numerical methods used in the industry for acoustic predictions are widely used for exhaust system optimization; however, the numerical and theoretical results in some cases differ from experimental tests because of the numerical limitation models, temperature variation which have high influence on speed of sound, subjective analysis, among others. For this reason, this article aims to demonstrate the relevant steps for acoustics development applied in automotive exhaust system and present a comparative study between experimental test and computer simulations results for each process. The exhaust system chosen for development was a popular car 4-cylinder 1.0-liter engine. The study starts with standing waves analysis for the exhaust system proposal and; fundamental and harmonic frequencies generated from the engine. Then, Transmission Loss tests were performed for acoustics components (Mufflers) searching for mitigate the noise level for the frequencies range. The results clearly demonstrated the differences and difficulties to adjust theoretical models with experimental. The ideal systems have good approach with theoretical conditions, while experimental became more expansive and functional, but this should not be cause of discouragement, and should be a motivation for engineers, because this necessity and need that transform and differ the knowledge.
2015-36-0279 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Incentives for electric vehicles in Brazil: an analysis based on the supply-side policies (technology-push) and market policies (demand-pull).
Autoria: EDGAR BARASSA
Resumo: This article aims to identify, analyze and classify public policies and government incentives to stimulate the development, production and market for electric vehicles in Brazil. Look at the sphere of the state is justified because the regulatory actions and public instruments are keys to providing a suitable environment to promote the new technology. The analytical method used in this paper is a classification of policies to stimulate demand (demand-pull), seeking to develop the market for a new technology and protect it against competitors; and supply policies (technology-push) aimed to reduce the cost of technological innovation and R & D of new technologies. As results of the survey, demand-side policies was identified included in INOVAR AUTO program and are restricted to the segment of hybrid electric vehicles, including a few types of vehicles. At the state level there was some actions such as discounts on taxes and some law projects under preparation.The suplly-side policies are isolated initiatives, exemplified by the actions carried out by MCTI and by CNPq in favor of the formation of specialized human resources; by BNDES, which supports / funds the new technologies that do not exist in the country. In short, it is concluded that there is not clear support for the development of electric vehicle in Brazil by public policies. Moreover, the initiatives found are characterized as incremental developments of technology and as improvement of staff and are very sporadic. Moreover, prevail the instruments for supply over to demand, which suggests greater effort by the State to develop the technology over its market. Such initiatives, however, should not be neglected in view of the potential in enabling the creation of specific competencies for R & D at the national level.
2015-36-0280 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: Study of the polymerography technique of the nylon 66 by reflection optical microscopy and scanning electron microscopy
Autoria: LÁZARO LOPES MACHADO NETO
Resumo: Currently, the technique of polarized light transmission microscopy is frequently used to study and analysis of the internal morphology of polymeric materials. However, this technique consists in obtaining specific equipment for preparation and analysis of thin sections of material obtained by microtome. This work studies an alternative to using optical microscopy analysis of reflection in the internal morphology Nylon 66. By Polymerography technique is possible to develop applicable methods for failure analysis, forensic analysis, characterization of materials and processes, quality control, and academic for research. The Polymerography consists in to prepare specimens using cutting, embedding in epoxy resin, grinding, polishing and etching, very similar to metallography technique used in investigations involving metal alloys. The study was performed using the chemical reagent Xylene to reveal the morphology of microstructures in spherulitic phases and amorphous phases present in Nylon 66. Samples were observed from the techniques of reflection optical microscopy (brightfield microscopy and Differential Interference Contrast (DIC )) and scanning electron microscopy (SEM).
2015-36-0284 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: MODELLING OF THE COMBUSTION INFLUENCE ON DIESEL ENGINES NOISE LEVEL FOR MAR-I APPLICATIONS
Autoria: EDUARDO NISHI
Resumo: Since January 2015, Brazil put into effect the PROCONVE/MAR-I (Programa de Controle da Poluição do Ar por Veículos Automotores para Máquinas Agrícolas e Rodoviárias), which drives the country to the same stringent emissions standards used by the American (EPA Tier III) and European (Euro Stage IIIA) markets. As a result, new pollutants and noise emissions levels were established and although very important for the society health, this issue (noise) has been left behind in this kind of vehicle. Therefore, an extremely challenging target has to be pursued, regarding the current political and economical situation and also the resources availability to achieve those targets. The present work investigates the influence of the noise generated during the combustion process in MAR-I engines by modeling the calibration parameters, which allows to identify the contribution of the combustion in the global engine noise and possibly reducing it and hence the product reckoned costs.
2015-36-0288 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Closed-loop control of a bench test drive system for automotive shock absorbers
Autoria: MARCELO VANDRESEN
Resumo: In a bench test for automotive shock absorbers of the mechanism type "scotch yoke", the angular velocity of excitation must be constant, but the load (resulting from the shock force) is a function of speed, resulting in oscillations in the speed along the course of the test, as a function of frequency inverter time response which controls the electric motor. Employing a closed loop control system on the drive system of the automotive shock absorber bench test will provide better quality at higher speeds and loads, thus allowing a better representation of the shock absorber condition. This paper presents the state of the art about researches in development that are linked to closed loop control of drive speeds mechanisms. It is developed a control system that maintains constant the test speed, regardless of the reaction load of the shock absorber, allowing the self-adapting PID values for a range of shock absorbers tested as a function of net load. The mathematical modeling of the problem is presented, quantifying the involved magnitudes. The concepts will be tested in a test bench prototype and the results with and without control will be shown for conventional and competition shock absorbers.
2015-36-0289 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Numerical analysis of the fluid flow in a prechamber for a spark-ignition engine
Autoria: FABIO DE CASTRO RADICCHI
Resumo: The use of torch ignition systems in spark-ignition engines represents an interesting option in the efforts to reduce pollutants emission and specific fuel consumption. Based on this idea, this paper presents a 3D model of a prechamber created for a spark-ignition engine and focuses on the numerical analysis of the fluid flow inside the modified chamber. This kind of analysis is very important once it allowed evaluating aspects like turbulence parameters, pressure inside the chamber and prechamber, fluid recirculation and a possible prechamber’s geometry for the engine. The studies were done in a four valve Single Cylinder Research Engine – SCRE. For the numerical modeling and fluid flow investigation was used STAR-CD Software. The numerical results permitted to characterize the fluid flow in the modified engine and compare it with the standard engine, which showed significant differences and an interesting potential.
2015-36-0296 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: High cycle fatigue behavior of AA 6351 and AA 7050 aluminum alloys
Autoria: ANA MÁRCIA BARBOSA DA SILVA
Resumo: The fatigue process is the main failure mode of aircraft structures, in which aluminum alloys are employed in approximately 70% of its structural components. Among the microstructural characteristics of aluminum alloys, the second phase particles provided by the ageing heat treatment have an important influence in their mechanical properties. In this context, current studies have shown that the two-step ageing heat treatment (T6I4) improves the hardening response and hence the mechanical properties of 6xxx and 7xxx aluminum alloys. This investigation presents a study of high cycle fatigue behavior of aluminum alloys AA 6351 (T6 and T6I4) and AA 7050 (T7451 and T6I4) as well the influence of microstructural characteristics and two-step ageing heat treatment in the fatigue properties of these alloys. Fatigue tests were performed on smooth and notched specimens, as well as fractographic and microstructural analyses. It was observed that the two-step ageing heat treatment decreases the notch sensitivity of the studied alloys.
2015-36-0299 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: Comparative analysis of atomization microscopic characteristics of gasoline and ethanol in a GDI injector
Autoria: CARLOS ALBERTO GOMES JUNIOR
Resumo: This study involves the comparison of atomization characteristics of gasoline and ethanol produced by a single-hole gasoline direct injection (GDI) injector. Experiments were performed for the fuel spray characterization, such as: measuring the mass of fuel injected, droplet velocity and droplet diameter of atomized fuel as a function of injection pressure. In the injected fuel mass measurement, an experimental apparatus was used consisting of a nitrogen cylinder, a source of generating pulses, a fuel tank as a pressure vessel and a precision weighing scale. To measure the fuel droplet velocity and droplet diameter, were used the known optical techniques: Doppler Anemometry e Phase Doppler Anemometry (LDA/PDA), respectively. Thus, the performance of fuels can be compared. The velocity distribution, droplet diameter and characteristic diameter, Sauter Mean Diameter (SMD), were evaluated and analyzed due to the injection pressure.
2015-36-0302 || Ano de publicação: 2015
Categoria: Meio-Ambiente
Título do Paper: BEVERAGE TRUCK WITH 100% DEDICATED COMPRESSED NATURAL GAS(CNG) ENGINE
Autoria: DANIEL JOSÉ RIBEIRO
Resumo: Some of the main drivers in the development of new technologies for commercial vehicles(trucks and buses) are the energy efficiency and the product operating costs; the search for new propulsion modes and alternative fuels should be a corporations engineering routine. The main reasons for the strong growth of the vehicle market powered by compressed natural gas(CNG) are related to the reduction of transportation costs(US$/km.t), low pollutants emissions, global fuel reserves, improvement of extraction process and refueling infrastructure, tax incentives, corporations engagement with environmental issues – the great potential of the Latin America and global market. With a strategy guided on innovation and sustainability – in order to evaluate the opportunities for the use of CNG in Brazil – MAN Latin America has developed a beverage truck project, with engine 100% powered by CNG(MAN E08 / Otto cycle/ 6,9l) and gross weight of 23t. The engine and the CNG system have an advanced technology regarding to materials, design, system injection and software(in order to get the better combustion efficiency). The project premise was to offer to the market a product with less environmental impact and a lower operation costs, and at the same time preserve the characteristics of performance, reliability and durability. In order to validate the project potentiality, a partnership with a large company in the beverage segment was established, where the vehicle operated for one year, under real applications conditions of distribution and urban collection. The fuel consumption and the performance were daily compared against others company’s similar diesel trucks, and the results were excellent: in addition to higher performance(due to higher torque and power), the CNG truck was 11% better than average of diesel trucks, in transportation costs. The environmental benefits of CNG are even greater when analyzing its diffusion in urban fleets such as beverage and garbage trucks, and buses. Additionally, the engine technology allows the use of others environmentally friendly solutions, like a Biomethane.
2015-36-0305 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: PIV measurements of in-cylinder tumble flow in a motored single cylinder optical research engine
Autoria: CARLOS ALBERTO GOMES JUNIOR
Resumo: The purpose of this work is to present an experimental methodology to characterize the in-cylinder tumbling flow generated by a motored four-valve spark ignition single cylinder optical research engine. High-speed two-dimensional Particle Image Velocimetry (PIV) measurements were made in the symmetry vertical plane between the inlet and outlet valves. The velocity flow fields were recorded during the intake and compression strokes for three different engine speeds (1000, 1500 and 2000 rpm) at several crank angles. Vorticity, tumble ratio and kinetic energy were calculated and compared. Also, an evolution analysis of the main vortex center was made. As result, the tumble ratio and kinetic energy showed a decrease at the end of intake stroke. Flow field cyclic variation could be noticed. The methodology contributes to a better understanding of flow motion behavior, and consequently, the mixture formation process in spark ignition engines.
2015-36-0306 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: “ACCELERATED DURABILITY TESTS OF COMERCIAL VEHICLES POWERTRAINS PERFORMED ON-ROAD BY A TOWING TRAILER WITH AN ELECTROMAGNETIC BRAKE”
Autoria: HARALDO REHDER
Resumo: Tests of commercial vehicles power trains as well as cooling systems can be performed on road or on stationary testing beds. Complete commercial vehicles can be tested on stationary chassis dynamometer, which could not be implemented in Brazil due to the high costs. Functional tests on road are not possible due to the lack of long up slopes availability. Therefore, the commercial vehicles in Brazil are normally tested on testing grounds by simulation of up slopes by towing one or more trucks, with obvious difficulties. Durability tests are performed on road running up and down slopes as well as flat roads, taking a very long time and high costs. To lower test time and costs, the test should be simulated only with up slopes. To perform an accelerated durability test on road of commercial vehicles, it is proposed to use a Towing Trailer with an electromagnetic brake. That trailer already mentioned in other occasions and initially foresaw for cooling test, was developed based on a sugar cane trailer to simulate up slopes due to an electromagnetic brake, controlled inside the cab of the truck (commercial vehicle) on test. A laptop localized in the cab accesses (Wi-Fi) and controls the electromagnetic breaking system on the trailer. The dynamic forces between tractor and Trailer are measured and registered by a Wheatstone bridge with strain gauges on the traction rod. The measure system shows and register the effect on the traction and compression forces during the acceleration of the convoy, gear changes, up and down slopes, breakings with the tractor and trailer system. Measurements were taken on flat ground, at 20 km/h (adequate for cooling tests) and 80 km/h with and without electromagnetic forces, showing the capacity of the electromagnetic system to simulate up slopes and the viability of the Towing Trailer. It was used a 420 HP tractor, over the Trailer brake capacity to evaluate the limits of the testing system. Finally, the forces were measured and evaluated WITH and WITHOUT electromagnetic braking force, on a public road with up and down slopes at a maximum speed of 85 km/h. It was shown that by the effect of the topography plus the electromagnetic breaking forces, the tractor can be tested at a higher level of efforts of the power train and therefore submitted to an accelerated durability test.
2015-36-0310 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: Vulnerabilities to “AUS32 Emulators “ and Proconve P8 challengesv
Autoria: EDMAR GOSI CAMARGO
Resumo: Aqueous Urea Solution (AUS32) dosing systems used in vehicles equipped with SCR (Selective Catalyst Reduction) complying with emissions standards Proconve P7 were developed with the goal of reduce NOx emissions in diesel cycle engines. Current legislation also forecasts the failure monitoring as well as its components tampering. There are several AUS32 dosing system architectures and each vehicle manufacturer is responsible to detect the system vulnerabilities and implement robust strategies to detect and alert failures in the system. However, some economic and political factors could influence on how much robust the system must be in order to the manufacturer could assure the system is working properly. Nowadays, there are specialized companies in finding ways to tamper the AUS32 dosing systems, from a sensor change to a high complexity electronic circuit able to learn the vehicle performance in order to emulate it. This kind of high complexity is hardly detected by current AUS32 dosing systems and is a challenge to Proconve P8 phase, once in Europe there are already emulators to work with Euro VI systems. Two factors contribute to the usage of such emulators in Brazil. First, AUS32 price is above what was expected. Second is the lack of surveillance from authorities. Emulators are easily found in auction websites and some of the sellers offer also the installation service in the vehicle, providing warranty as if a licit product. The objective of this work is to present the challenges that must be addressed by Proconve P8 such a way to discourage the usage of emulators. Proconve P7 compliant vehicles with deactivated AUS32 dosing system can produce 300% more NOx and are comparable to Euro II or Proconve P4 compliant vehicles.
2015-36-0311 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Importance of conrods and crankshafts roughness accuracy on sliding bearing performance
Autoria: LARISSA GALERA
Resumo: In recent years, the concern about pollutants emissions has been raised as well as customer requirements for more efficient internal combustion engine (ICE). To attend this demand, new technologies have been introduced in ICE, such as smaller engine bearings, cylinders reduction, variable displacement, peak cylinder pressure (PCP) increase, inter alia. Sliding bearings are responsible for vital function under engine operation and also friction losses, impacting on fuel consumption as well as pollutants emissions. To maximize bearings performance, it is important to guarantee a hydrodynamic regime, in order to reduce wear and avoid power loss due to metal-to-metal friction, and consequently, premature failure of engine components. Material roughness indicates, with oil film, the lubrication regime as boundary, mixed or hydrodynamic one. So, it is important to characterize sliding bearings through its roughness aiming the tribological performance parameters optimization, which impact on fuel consumption. Altogether, this work shows different ways to characterize the bearing roughness for simulation, and the influence of this parameter on bearing performance.
2015-36-0312 || Ano de publicação: 2015
Categoria: Interiores e Cabines
Título do Paper: Ecologic cabin - INovation and sustainability
Autoria: BRUNO DE OLIVEIRA AZEVEDO
Resumo: This paper presents sustainable alternatives for production of automotive vehicles. The case was conducted at the company MAN Latin America, bus and truck manufacturer, located in Resende - RJ, in which the product was evaluated the vehicle Constellation, one of the bestselling models in the market following trucks. Always seeking innovation of its product line, and advancing possible environmental legislation and market needs, the company led the development and production of a Constellation cabin with greener parts applied in their internal and external trim. The project was based on the replacement of petrochemical materials, and more complex for recycling, by renewable materials, recycled and efficiently produced. This way, some parts had their modified components and manufactured using those materials, applying the ecological concept. Articulated in four key areas (plastics, rubber, natural fibers, and foams) the project resulted to the offer of ecological cabin "tailor made", which preserves the same quality and functionality as valued and recognized in Volkswagen trucks. As a result, was obtained a weight reduction of 12,4 kg and a value of 18,04% produced by renewable materials, recycled and efficiently produced materials, corresponding to the total weight of the cabin. Besides, it was identified the possibility of using less non-renewable raw materials and consequently generating fewer emissions throughout the production chain of the applied parts.
2015-36-0316 || Ano de publicação: 2015
Categoria: Interiores e Cabines
Título do Paper: INTERIOR PLASTIC SURFACE GRAIN DEVELOPMENT - FROM DESIGN CONCEPT UP TO GLOBAL VEHICLE LAUNCH
Autoria: MARCELO LUIZ VIEIRA LOSS
Resumo: INTERIOR PLASTIC SURFACE GRAIN DEVELOPMENT - FROM DESIGN CONCEPT UP TO GLOBAL VEHICLE LAUNCH Present a fully molded in color interior plastic grain development from Design concept up to global multiple production plants launch. Starting on Interior Design and Color&Trim theme developing and approval, fallowing chemical etching and master sample development up to physical parts markup, tools etching and production tryouts. Case: Ecosport interior main grain – Design, Development, Master distribution, parts markup, tool chemical etching and parts try out up to and final parts approval for production quality control.
2015-36-0319 || Ano de publicação: 2015
Categoria: Meio-Ambiente
Título do Paper: Carbon Canisters and the evaporative emission level tendency in Brazil for passenger cars
Autoria: ROGERIO DA SILVA COUTO
Resumo: Carbon canisters are used in gasoline passenger vehicles and light duty truck applications. The component is part of the vehicle emission control system. The carbon canisters utilize a carbon bed to trap hydrocarbon vapors from the fuel tank also and vapors created during the fuel tank refueling and venting events. Canisters design, charcoal type and performance have been driven by emission level standards in different regions around the world, since evaporative emissions requirements have enhanced along the years. The evaporative emissions requirements tendency in Brazil indicates the use of improved carbon canisters in a near future. In summary, the canister is needed to store hydrocarbons that would otherwise pollute the environment. The end result is a healthier earth on which we live.
2015-36-0320 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: nonlinear dynamic model of a commercial vehicle and the variables that can affect the fuel consumption
Autoria: RICARDO FERREIRA GASPARINI
Resumo: This paper will present a non-linear dynamic study of interaction between commercial vehicle and the environment, considering all the influence of their dynamic characteristics in the fuel consumption. The first step is to analyze all variables that influence the dynamic behavior and then construct a mathematical model based on energy and based on forces (Newton). The interaction between the vehicle and it’s environment and the response of it will be considered as influent aspects and should be included into vehicle dynamic modeling. By understanding this relationships and their influence in the fuel consumption it is possible to propose a new approach to develop automotive projects for commercial vehicle applications focus on fuel consumption and taking into account the Brazilian reality.
2015-36-0321 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Fuel Consumption Optimization in a MD Diesel Engine using Analytical Tools
Autoria: SERGIO LEAL SOARES
Resumo: Nowadays the industrial market has been shown an increasingly demand for efficient thermal machines. Particularly in the automotive field, the market is requiring strong reductions in emissions together with fuel consumption. It is important to be aware that the reduction both in emission and fuel consumption represents a challenging task, since it is one of the most complex trade-off of a diesel engine from the engineering stand point. The daily life in big cities motivates the proposal of stringent emission regulation standards by government agencies with the purpose of improving the quality of the life of people. These policies usually drive the definitions of engineering targets for the product development. The middle duty diesel engine (MDD) plays an important role in the commercial vehicle worldwide with the main objective of transportation of goods and people. The present paper describes a comprehensive methodology to reduce the fuel consumption without jeopardizing engine emissions, particularly NOx, and the after treatment durability aspects including urea crystallization hazard and catalyst efficiency. The engineering procedure proposed here comprises the analysis of customer representative route using 1D simulation, customer steady-state chassis dynamometer test and the required emission cycles (ESC and ETC), which provided the first estimation of candidates for working points in the engine operation. Then, a full-factorial Design of Experiments (DoE) was done over a smart range of each one from the most important combustion parameters in order to accommodate the NOx and fuel consumption trade-off. The evaluation of the results was done based on cycle integrated emissions levels, fuel consumption at the customer route via simulation and chassis dynamometer tests. Undesirable occurrences like crystallization and efficiency drop in the after treatment (ATS) were as well verified. Additionally, the vehicle performance was investigated using simulation of typical accelerations modes and grade ability to further pursue additional improvements. It was found significant improvements in fuel consumption of nearly 3.5% at the chassis dynamometer. The total improvement in the customer vehicle route was estimated nearly in 2% using vehicle simulation.
2015-36-0324 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Influence of InertiaL Forces and Mass Balancer on Internal Combustion Engine Dynamics
Autoria: ANDRE BARONI SELIM
Resumo: The combustion engines evolution makes the engine manufacturers look for projects focused on downsizing, more powerfull, lighter, with great fuel consumption, less noisy, etc. With special attention to NVH, specifically to vibration issue, this work aims at studying the influence of mass balancer and inertia forces coming from engine internal components on internal combustion engine dynamics supported by vibration dampers. For mass balancer study several experimental analyses were performed with a dynamometer. The conclusions are obtained by comparison between measured engine displacements with and without mass balancer. To study the influence of inertia forces from engine internal components, a mathematical model was developed. In this model the inertia forces act on a rigid body, the engine crankcase, supported by four vibration dampers and with six degrees of freedom. Some modifications are made on engine internal components such as mass and geometry observing what is their influence on internal combustion engine dynamics. The mathematical model is validated by comparison against experimental analyses.
2015-36-0325 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Influence of the positioning and characteristics of the cushions in the dynamic response of a four cylinders diesel engine.
Autoria: WAGNER ROSSI DE SA
Resumo: SÁ, Wagner Rossi de, Influence of the positioning and characteristics of the cushions in the dynamic response of a four cylinders diesel engine, MWM International Motores, Universidade Estadual de Campinas. In the application design of diesel engines to various types of vehicles, there are different technical solutions with respect to the position, type and number of engine mountings to the structure: rigid fixation, rubber bumpers, symmetric, asymmetric, etc. Among the many possible solutions, there are limitations and specifications in the application design that should be considered and could bring as a consequence a dynamic behavior is not desirable to the engine and its structure, and, in addition, may also affect your users as well as for the comfort . In this work were developed the kinematic and dynamic analysis of the diesel engine mounted on cushions, from nonlinear equations of motion and their integration to obtain the vibrating responses of the engine. This model allows from response values of the system, analyze different positioning settings of cushions, the sensitivity of small deviations in the positioning of the same, as well as can interact with different constructive types of cushions and their characteristics for qualitative and quantitative assessment of the dynamic system changes. This work brings a lot of positioning analysis, cushions features and most influential factors applied to a four cylinders diesel engine, in order to obtain an improvement in engine dynamics.
2015-36-0329 || Ano de publicação: 2015
Categoria: Chassis e Cabine
Título do Paper: Comparative analysis of torsional rigidity of a chassis of an automotive prototype obtained by numerical analysis and experimental
Autoria: ANTONIO FLAVIO AIRES RODRIGUES
Resumo: This paper has as main objective to analyze numerically and experimentally, the torsional stiffness of the chassis of an automobile prototype designed to carry two people and a small load on urban roads and highways. Knowledge of the structural rigidity of the chassis is important because it influences the dynamic behavior of the vehicle. The same should have a good relationship between mass and stiffness, aiming at a reduced mass. In numerical analysis, the stiffness of the chassis was obtained with the use of Finite Element Method (FEM), where the numerical model was formulated using shell elements. Seeking to improve the method of predicting the structural rigidity of the chassis of the prototype, was performed an experimental procedure, in which was applied to the chassis, the same loading conditions and fixings used in numerical analysis, so one can compare the results obtained in the experimental analysis with the result of numerical analysis. The torsional stiffness of the chassis obtained from the numerical model was approximately 25% higher than the stiffness obtained experimentally.
2015-36-0333 || Ano de publicação: 2015
Categoria: Ruídos e Vibrações (NVH)
Título do Paper: Study of acoustic absorption of seat foams and fabrics
Autoria: CARLO SARTORI BONFIM VEZZÁ
Resumo: The acoustic comfort inside the vehicle justifies important attention during its development phase, because customers desire a quiet interior to have a more relaxing environment, easier to have conversations and to listen to the radio. Generally, acoustic insulators are distributed on vehicle body to minimize the portion of noise that enters the vehicle and, in the interior, absorber components are used to reduce the cabin noise reverberation. External noise is attenuated by deadners and felt or foam insulators, located in the engine compartment and on all the vehicle body. Internal noise absorption is mainly due to headliners, carpets and seats. In order to contribute to the sound absorption inside the vehicle made through the seats and also to propose a foam and fabric configuration that demonstrates the best acoustic performance, this work aims to compare combinations of four different foam densities with three different fabrics weights using the Kundt´s tube. The idea is to understand what are the influences of the foam and fabric characteristics on the seat noise absorption performance and, balanced with seat performance requirements, such as safety, durability, comfort and others, propose the best scenario for seat contribution of interior noise absorption. The foam densities and fabric weights were selected based on current production vehicles from different segments in order to consider a good range for testing both materials, and the best scenario identified by the comparison shall be evaluated in vehicle scale prior to implementation in a next new project.
2015-36-0335 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Start Energy Efficiency on Flex Fuel Engines
Autoria: VICTOR HUGO SOARES ALGATE
Resumo: The new Brazilian legislation INOVAR AUTO coming in 2017 has raised the level of efficiency awareness from vehicle fuel economy in km/L to energy consumption in MJ/km. In this scenario, automakers are implementing several vehicle optimization strategies and new technologies to meet vehicle energy efficiency targets and consequently reduce fuel consumption and exhaust gases emissions. One of these technologies is the START-STOP system that turns the engine off when the vehicle is at idle and after some safety and operating trigger conditions are met. A new concept has been develop to evaluate an internal combustion engine start efficiency considering both the electric energy provided by starter motor and the fuel chemical energy required to start and sustain combustion. This concept of start efficiency is of particular interest for Flex Fuel engines when there is a high difference in energy content level between gasohol (E25) and hydrous ethanol (E100) fuels. The method showed to be adequate to parameterize engine start events in addition to conventional parameters like starting time, quality and flare. Furthermore, it has been possible to compare total energy required for starting against idle energy consumption. This paper presents the engine starting efficiency concept and the results of a 1.0L Flex Fuel engine tested with E25 and E100. The effect of start efficiency parameter in function of coolant temperature was also investigate for both fuels.
2015-36-0336 || Ano de publicação: 2015
Categoria: Ruídos e Vibrações (NVH)
Título do Paper: Exhaust system prototype parts tailpipe noise performance variability
Autoria: FABIO GUILHERME FERRAZ
Resumo: Exhaust system noise has significant impact on vehicle exterior and interior noise. In a vehicle development, during early design verification phase, the exhaust tailpipe orifice noise performance is measured and validated at the proving ground tracks using design intent prototype parts developed and delivered by supplier, following previously technical specifications agreements and specific package constrains and targets. At late design verification phase, new measurements are performed in production intent prototype parts, and the results achieved are compared with initial measurements made for design intent prototype parts - with conflicting results in some situations. This work presents a project where the scope is to identify opportunities to implement parts variability and robustness control in the current prototype building and assembling process of the exhaust system supplier, to ensure representative prototype parts in terms of tailpipe noise performance and also find opportunities to improve the current tailpipe noise measurement made at the proving ground tracks.
2015-36-0345 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Correlation between Aerodynamic drag found on CFD simulations, Wind Tunel testing and CoastDown testing
Autoria: THIAGO LUIS ZOLET
Resumo: It is known that aerodynamics influences directly on a vehicle´s fuel consumption, especially at speeds above 45-60km/h, where it becomes the main parasitic loss. With increasing pressure on automakers to develop more efficient vehicles, aerodynamics is playing a crucial role in the goal of saving vehicle´s fuel. Usually aerodynamic development starts in the early stages of the project, responsible engineer works together with designers and body/ergonomics engineers, using CFD simulations as tool. At certain point in the development time line, full scale or scaled models are manufactured and tested in wind tunnels, where vehicle gets a refinement on its external aerodynamics. However, the measurement of aerodynamic drag which is effectively used for homologated vehicle´s fuel consumption is done by coastdown testing. This paper shows a correlation between results from CFD simulations and results measured from wind tunnel and coastdown testing. Same vehicle was used in all tests, divided in two stages.Tthe first one used the vehicle exactly as it is when left production assembly lines and in the second step the same vehicle was equipped with an aerodynamic kit, which aims to reduce its drag and hence its fuel consumption.
2015-36-0348 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Prospects for future non-manual transmissions developments for vehicle aplications in Brazil
Autoria: RAFAEL VECCHIO FORNARI
Resumo: The purpose of this paper is to present the origins and the technology of the different types non-manual transmissions systems currently available and the wide potential to incorporate such technologies to the vehicles built in Brazil. The brazilian market is experiencing a huge increase in automated and automatic transmissons vehicles share, and the OEMs are adopiting different strategies to offer competitive products with affordable prices to enter in this segment. Many different alternatives are available, and there is no obvious winner. This paper will describe the concepts, the architecture and the operations of such systems and pointing out the advantages and disadvantages of each one. The message of this paper is to point out the different alternatives of non-manual technologies currently available on developed markets and the great potential we have to bring these technologies to the car makes in Brazil for the bennefit of the customer and the Brazilian economy.
2015-36-0353 || Ano de publicação: 2015
Categoria: Chassis e Cabine
Título do Paper: STATIC AND DYNAMIC ANALYSIS OF A CHASSIS OF A PROTOTYPE CAR
Autoria: ANTONIO FLAVIO AIRES RODRIGUES
Resumo: The aim of this work is to design and analyze the structure of a chassis of a sports car. The chassis structure is fundamental in design efficiency, for in it are fixed mechanical parts that make up the steering system, suspension, and traction, among others. The chassis geometry was designed in SolidWorks 3D CAD program and the numerical analysis was performed using the Finite Element Method (FEM) with FEMAP program. The chassis was designed using average surfaces in order to use the formulation of shell elements on analysis with finite element method. Using this methodology was possible to realize static and dynamic analysis to check how the structure will behave when subjected to static and dynamic loads during travel the vehicle. The analysis allows to estimate the magnitude and the form that loads acted on the chassis frame. Thus, one can determine the points of least resistance and alter the geometry to eliminate critical points. The results were used to evaluate the project with respect to their suitability the norms used to verify security, and if the structure is suitable for a sports vehicle with tubular chassis. The results were a torsional rigidity 1639 Nm / °, meeting the standards of a ladder frame type according to the standard Fiat, Torino, 2002. The vibration frequency modules obtained in the analysis was 34.4 Hz for the first module and 41.5 Hz for the second module.
2015-36-0356 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Finite Element Modeling for Orthogonal Cutting Process
Autoria: UILE PIRES BORGES DA SILVA
Resumo: Nowadays the industries are using in large-scale the modeling of components by the finite element method to predict and anticipate events with the control variables of a project, such as, forces, displacements, moments, stress, etc. In machining processes, the control of these variables makes the process more stable and effective, therefore the use of CAE tools promotes better control of time and costs in the process. The CAE tools are designed to derive a computational model to predict strain, stresses and the efforts on the work-piece, as well as the load on the cutting tool according to specific machining parameters, such as cutting speed, tool advance, machined material, tool geometry and others. This paper covers the use of the finite element method to simulate the machining process by orthogonal cutting using the explicit method and based on Johnson-Cook formulation for the material behavior, when the work-piece is subjected to high strain and heat generation during the machining processes. In that way, it is considered that heat is transferred through Conduction between Cutting tool and work piece. This study aims to determine the cutting force during the machining process, which is a control variable for the process.
2015-36-0357 || Ano de publicação: 2015
Categoria: Sistema de Transporte
Título do Paper: The more comprehensive use of embedded technology for quality improvement of the national public transportation system.
Autoria: BRUNO SCARANO PATERLINI
Resumo: The several problems and bottlenecks faced users public transport users in big cities are a common knowledge. Among them agencies responsible for public transport recognize the lack of centralized control, the under and over supply, the lack of information to users and the non-compliance of scheduled trips. In order to work identified problems improving cities like Recife and São Paulo are testing systems named as embedded technology that integrate the use of GPS, cameras, centralized monitoring among others, retarding a deeper coverage compared to systems previously used. The main objectives are the comfort and safety increase of users and the freight logistics improvement. This paper presents the technologies being tested in Brazil through successful models applied in countries as Spain and Colombia, as well as the scope of bids and proposals for improvement of public transport.
2015-36-0359 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Formula SAE Aerodynamics: Design process with focus on drivability
Autoria: MARIO EDUARDO SANTOS MARTINS
Resumo: This paper presents the design process of an aerodynamic kit for a Formula SAE competition vehicle using computational fluid dynamics (CFD) with special attention to the distribution of aerodynamic loads. The work was based on the knowledge gained in the 2014 prototype design but with corrections to fit it to the 2015 Formula SAE rules, which are much more restricted especially in the dimensions of the wings. With the reduction of area, airfoil profiles and their position had to be optimized for the downforce to remain significantly beneficial with an acceptable drag. As a result the complete kit provides a downforce at 60 km/h (average speed provided by the rules) which is equivalent to 23% of the vehicle total mass. Another important fix was in load distribution, which directly affects driveability. The paper shows the solution and a discussion about why it is different from the solution commonly found in the literature. Finally a prediction of lap times in all dynamic events of FSAE competition with and without the aerodynamic kit was made. It is concluded that despite the extra weight and aerodynamic drag caused by the kit it allows lower times in 3 of 4 dynamic events with a large increase in total score.
2015-36-0364 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Design, Manufacturing and Testing of a Long Endurance UAV – Effect of Control Simulations
Autoria: EVERTON SPULDARO
Resumo: A long endurance high efficiency Unmanned Aerial Vehicle (UAV) is being developed by a group of researchers and students in the Mechanical Engineering Technology program at Algonquin College, Ottawa, ON, Canada. The design is based on a tailless tandem staggered wing configuration, with a carbon fiber frame and electric propulsion. The developed aircraft has a maximum weight of 12.5 kg, well within the 25 kg limit outlined by Transport Canada for permission-free operation. The UAV was designed to fly missions exceeding 24 hours, performing surveillance and oil pipeline inspection, either autonomously or under radio control from a ground station, with high payload capacity. This paper describes the process of designing, manufacturing and testing the developed configuration. The operational requirements are delineated as conceptualized by the development team. A description of the prototype development, including aerodynamics, structural and stability performance, and stability derivatives is included, based on data generated through analytical analysis, simulations in the aerodynamics and stability design software, XFLR5, and testing. The configuration was developed and modelled in the software package SolidWorks, leading to the manufacturing plans for the prototype - a technical description is provided. As this UAV performs radio controlled and autonomous flights, it makes use of the APM Arduplane, which is an open source hardware and software package. In order to achieve PID tuning, Hardware in the Loop (HIL) simulations were performed between the autopilot board and two computers simultaneously running the Mission Planner software and the flight simulator X-Plane 10 software. A description of this tuning process is provided. The paper concludes with a description of performed flight tests, documenting performance achievements, and an outline of recommendations for further development.
2015-36-0373 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: EXPERIMENTAL CHARACTERIZATION OF ETHANOL SPRAYS FROM A SINGLE HOLE DIRECT INJECTION INJECTOR
Autoria: MÁRCIO EXPEDITO GUZZO
Resumo: This study concerns the sprays produced by a single hole direct injection injector through a systematic image treatment methodology. The images were obtained by high speed recording associated with shadowgraph technique. The recording frequency was 6504 Hz. Grayscale images were obtained after a process of histogram adjusting and image subtraction. The spray geometry was evaluated through a process of edge detection in the hollow cone of the spray injection. A criterion based on pixel values was taken to localize the spray edges. The high pixel values were associated with liquid phase while the low pixel values were associated to its absence. Computational codes written in Matlab environment were used to analyze the numerical matrices associated to the images. The high frequency image recording allowed studying the sprays in the beginning of injection and also to evaluate the penetration rate. The tests were conducted with injection pressure variation. The injection pressures in this work were 30, 50, 70, 90, 100 and 110 bar. EXXSOL D60 was the tested fluid to simulate ethanol fuel properties and EXXSOL D40 was the tested fluid to simulate gasoline properties. Nitrogen was the gas used in a pressurized chamber to give the required injection pressures.
2015-36-0374 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: A Case Study of Model Based Design for External Lighting Systems to Automobile:MIL, SIL, PIL and RCP
Autoria: JOÃO HENRIQUE ZANDER NEME
Resumo: The demand for embedded systems is growing exponentially. The quest for more secure systems for automobiles leads to a higher number of specifications and control functions, which in turn increases the complexity of automotive embedded systems. This fact also drives the complexity of the development of these systems. The automotive industry operates in an aggressive market, obliging suppliers to align its quality strategy to constant improvement. Therefore, automotive manufacturers are seeking more efficient approaches for embedded system development. The model-based approach reduces develop time and improve quality using modeling techniques and simulations that give access to comprehensive, easy to interpret results at early stages of development. The use of automatic tests and executions maximize early validation capabilities and allows the developers to reuse designs and test cases. This paper analyzes Model Based Design’s methods, such as Model-in-the-Loop, Software-in-the-Loop using Matlab/Simulink to model the chosen system and MicroAutoBox from dSpace to perform the Rapid Control prototyping. The main goal is to prove the effectiveness of these methods in order to develop automotive software more efficiently and using fewer resources.
2015-36-0377 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Numerical analysis of an internal combustion engine using one-dimensional computational models
Autoria: FABIO DE CASTRO RADICCHI
Resumo: One-dimensional models for internal combustion engine analysis are very complex and useful to simulate its systems through a relatively low computational effort. Based on this idea, this paper presents the simulation of a spark-ignition engine using one-dimensional models implemented in a software developed by the authors. It was used a four valve Single Cylinder Research Engine, running at 3000 rpm. The numerical and experimental data were compared in order to evaluate the quality of the model, which included the analysis of the pressure, temperature, mean effective pressure, apparent heat release, mass burnt fraction, among other aspects. The numerical results presented good agreement with the experimental data, showing an interesting potential for the software, and some other points which could be refined in the future to make the software even more reliable and practical.
2015-36-0381 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: SIZING OF A STRUCTURE SANDWICH CORE
Autoria: JULIO EDUARDO FORSTER
Resumo: Multiphase composite structures are designed to enhance specific properties and for greater structural efficiency, sandwich panels where the external plates involve a less dense core material, exhibit a specific strength (σ / ρ) rather favorable, being indicated for applications that require mechanical strength and low weight. This work aims to scale a sandwich-like structure formed externally by unidirectional carbon fiber cloth boards with epoxy matrix involving a core type honeycomb, in various sizes, for which it is seeking an optimization. This study is directed to the participants aircraft structures Competition Aerodesign SAE Brazil, where there is the challenge of designing a lightweight, rugged aircraft. The outer layers were laminated in a vacuum bag at a controlled pressure, while the core was constructed based on PLA (Polylactic Acid) in a 3D printer. To assess the strength of the composites generated due to the different mounting positions of the core material, specimens were sampled according to ASTM standard D-790-02 and then bending tests performed according to ASTM E 855-90 standard, determining thereby the specific resistance (σ / ρ) of each generated material. The specific resistance showed a relation to the increase of the honeycomb of the honeycomb with the density, improving structural efficiency.
2015-36-0391 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Sensitivity analysis of multiparameter numerical model of quenching process using electromagnetic induction heating.
Autoria: PEDRO AUGUSTO LANZA PAULA
Resumo: Quenching process are widely used to improve fatigue strength of mechanical components that are subjected to cyclic loads in service. The depth of the hardened layer is directed linked with the fatigue and impact strength. So, to improve the mechanical properties in order to preventing fatigue failure in service, its very important to understand the process and the influence of its parameters. In this paper, a sensitivity study of the influence of some process parameters on the hardness profile of a crankshaft’s crankpin after quenching process using will be presented. The proposed simulation method include two stages: heating and cooling. In the first stage, the mechanical component, initially at ambient temperature, is heated by electromagnetic induction to a temperature above the steel austenitization. In the second one, the component is cooled by liquid immersion. The resulting microstructure is calculated using the Johnson–Mehl–Avrami–Kolmogorov model and Sheil’s additive rule for diffusional transformation, while austenite-martensite transformation is calculated by Koistinen-Marburguer equation. The simulation takes into account thermal properties as a function of temperature and microstructure and electromagnetic properties as a function of temperature and strength of the electromagnetic field (magnetic permeability). The results of the sensitivity study can help in the process setup, decreasing the number of experimental tests.
2015-36-0392 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Advanced PFI: the economical, high-performance systems approach
Autoria: TULIO I.E. COLETTO
Resumo: With Advanced PFI, Bosch has demonstrated that gasoline port fuel injection is becoming significantly more energy-efficient by means of innovative system development. Advanced PFI combines pressure increase, twin injection, PFI scavenging, and open valve injection. The use of Advanced PFI makes it possible to reduce consumption by 12%, with a corresponding decrease in CO2 emissions. The higher compression in the part-load range (OVI) alone accounts for 2% of the reduction. The remaining 10% come from downsizing with turbocharging and PFI scavenging. At the same time, Advanced PFI allows a reduction in HC emissions. Thanks to more homogenous air-fuel mixture formation and reduced manifold wall fuel condensation, HC emissions fall by 20% in the test cycle. Later ignition angles mean that the catalytic converter heats up faster. And last but not least, Advanced PFI also permits an increase in specific engine power output, with PFI scavenging achieving significantly higher low-end torque.
2015-36-0400 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: A new clock synchronization algorithm to compensate the initial de-synchronization of clocks based on a deadbeat controller for networked control systems.
Autoria: ELOY MARTINS OLIVEIRA JUNIOR
Resumo: Aerospace, automotive and aeronautical control systems demand high performance, precision, accuracy, modularity, integration, dependability and other attributes. Currently, to supply these requirements, engineers are using Networked Control Systems (NCSs) with Time Division Multiple Access (TDMA) databuses. They are part of Distributed Time Based Architectures (DTBAs) that provide the infrastructure for the design and implementation of safety critical distributed systems. These architectures provide a common time basis among the nodes of a system. However, the benefits of this approach face the challenge of establishing a common time basis among the nodes of a distributed system since startup until shutdown. For this, clock synchronization algorithms are used to achieve a common time basis within some precision and/or accuracy among the nodes of a system. So, clock synchronization algorithms become a critical part of designing distributed systems. But most of them suppose the clocks initially synchronized, what is unrealistic. This paper presents a new clock synchronization algorithm to compensate the initial de-synchronization of clocks based on a deadbeat controller for networked control systems. To do that, it presents a review of the literature, the new algorithm, its discussion, modeling and simulation. The results show: 1) the features of the problem of initial de-synchronization of clocks in a NCS; 2) an evaluation of the new clock synchronization algorithm proposed based on a deadbeat controller; and 3) the improvements of the clock synchronization algorithm proposed over the NCS performance.
2015-36-0401 || Ano de publicação: 2015
Categoria: Meio-Ambiente
Título do Paper: Particulate matter emissions from a flexfuel gasoline direct injection vehicle
Autoria: LUIZ CARLOS DAEMME
Resumo: Gasoline direct injection (GDI) vehicles are considered to be one of the solutions for engine optimization with regard to fuel consumption. This combustion system, which uses a heterogeneous or stratified charge, rather than the conventional homogeneous charge, potentially provides, depending on the duty cycle, an improvement in fuel economy of 5 – 10%. In Brazil, mainly due to new requirements to reduce consumption imposed by the Inovar Auto automotive regime, this technology is becoming more popular. In 2014, the first flexfuel GDI vehicle was produced in Brazil. However, GDI engines tend to produce more particulate matter (PM) compared to conventional engines. The present article is based on the study of particulate matter emissions from a GDI vehicle. A flexfuel vehicle was tested over a chassis dynamometer according to the FTP75 and HWFET cycles. The vehicle was fuelled with gasoline (A22) and with hydrated ethanol (EHR). Regulated emissions such as THC, CO, NOx and NMHC were measured as well as particulate matter and the fuel consumption. PM was quantified by gravimetric determination, according to current regulation applied to Diesel vehicles. PM was also analyzed by using a scanning electron microscope (SEM), in order to provide a semi-quantitative analysis of the composition and particle size. The results indicate that the particles adhered to the filter size around 2 microns and its composition revealed that they have higher concentrations of fluorine and carbon and minor amounts of silicon and oxygen compared with a baseline (new filter element). It was also observed in most filters one agglomeration of particles with sizes smaller than 0.5 microns. Those particles consist essentially of the same elements of the adhered particles. Regarding the total PM mass it was observed that emissions from A22 gasoline exceed the ones from EHR. It was also observed that PM emissions from HWFET cycle are higher compared to the FTP 75 cycle.
2015-36-0403 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: Solubility analysis of ethanol AND diesel oil with biodiesel (b7) blends
Autoria: JOSÉ RICARDO SODRÉ
Resumo: The solubility of ethanol in diesel oil with biodiesel is determinant for its use as fuel for compression ignition engines. The stability of blends of ethanol with concentration varying from 5% to 20% in diesel oil containing 7% (B7) and 20% (B20) of biodiesel was evaluated at temperatures from 15°C to 35°C. The blends were conditioned in burettes and kept at the test temperatures, being observed the blend phase separation percentage in specific periods of time. The results show the time for stability of each blend, indicating the maximum storage and use periods for each ethanol concentration used. For the highest ethanol concentrations the results demonstrate that it may be necessary to use emulsifying agents to keep mixture stability.
2015-36-0409 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Development of a fsae racecar cooling system
Autoria: GABRIEL KUNTZER
Resumo: The performance required by the actual spark ignition engines have increased the demands on the cooling system. In addition, in formula style competitions like Formula SAE the use of aerodynamics brought new problems about airflow restriction, requiring a complex study in the heat exchange area. As to better understanding as to do a detailed examination of this area, like a computational fluid dynamics (CFD), the characteristics of the main elements must be determined. To make this possible the paper presents a method of calculations and measurement to the NTU of the heat exchanger and the pressure loss through the radiator core in a steady state case. The water pump flow rate was measured and a diagram was made. In the air side, the heat exchange are made by the pair of fans pulling the air, so they were subjected to a anemometer test and the mass flow rate of air was determined. Closing the necessary data for calculating the heat carrying capacity the prototype was tested with four temperature sensors, two on the water and two on the air, getting the temperature change due to the heat exchange. With this data, the paper presents the heat exchange diagram, the case analysis and improvements that can be made on the system.
2015-36-0427 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: The bake hardening effect on 22mnb5 steel
Autoria: MARCOS ROBERTO DE CASTRO
Resumo: The current auto bodies projects seek to build light structures whose immediate impact is the reduction in fuel consumption for of internal combustion engines, and longer battery life for electric and hybrid vehicles. Reduction in fuel consumption means reduced emissions. The structures need to be lightweight, but increasingly resistant in order to provide maximum comfort and safety to the occupants. These assumptions have led to the development of materials. In the case of the steels hot stamping has allowed significant improvement in the mechanical properties. In recent years, hot stamped parts took prominent place in the structure of auto bodies to be in line with the mentioned demands. There are a lot of researches going on for this technology: materials, means of production, coatings and applications. The most commonly used steel in this process, 22MnB5, also exhibits the bake hardening effect: their yield strength is increased after thermal treatment at temperatures close to 200 °C.
2015-36-0431 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Performance analysis of genetic algorithm on gear pair design and optimization
Autoria: JOED HENRIQUE PAES
Resumo: Gear design techniques usually results on heavy drives that is contradictory to the tendency of mass reduction on the applications on modern road vehicles. This paper proposes the utilization of a genetic algorithm to design and optimize geometric parameters of a transmission stage comprised of two steel gears. Although genetic algorithm is not an optimization technique on a straight sense, its use is increasing in several applications where the design space is multidimensional. In this study, the fitness function proposed is a weighted average of critical performance factors on gears design such as total drive weight, tooth contact stress, bending stress and total space occupied by the assembly. In the genetic algorithms, weaker solutions may be formed by strong components which could prove useful following the recombination process. Based on this, the population evolution is constrained by the selection of how many non fit individuals can pass their genetic information to the next generation. The results show the influence of this parameter on performance of the algorithm to find out the optimal transmission design.
2015-36-0436 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: APPLICATION STUDY OF A CONTINUOUSLY VARIABLE TRANSMISSION (CVT) ON A PROTOTYPE OF FORMULA SAE
Autoria: CARLOS AUGUSTO PEREIRA COSTA
Resumo: The use of automatic transmissions currently is associated with softness and comfort while driving, and almost never during races. Despite the many benefits that its application can provide, there is still in the auto racing field a fear of the implementation of this system. Many sport steering fans prefer the manual, sequential or semi-automatic transmissions, because of the fact that in automotive competitions, it is the driver who sets the best time to change the gear. However, the use of Continuously Variable Transmission (CVT) does not only keep the engine always at its best power range, but also eliminates waste of time between gear changes, which can theoretically ensure more uniform and efficient acceleration. In this work, we studied the application of a continuously variable transmission in the Formula CEFAST team`s prototype at the Federal Center of Technological Education of Minas Gerais (CEFET-MG) in Belo Horizonte. Initially, it was developed a project of a Toroidal CVT for an application without major changes in ES-08 prototype (2014), defining its ratio range. It was developed a routine using the Simulink software to evaluate and compare the performance with and without the CVT system in one of the tests during the competition: the acceleration testing, which objective consists in perform the lowest time in a 75 meters straight circuit. The results showed that the use of CVT in the prototype has reduced the time in the test, what could have given the team a higher score. The benefits can be extended to any other test of the competition.
2015-36-0442 || Ano de publicação: 2015
Categoria: Gestão e Desenvolvimento de Produtos
Título do Paper: Monozukuri: a mapping of the application in automotive supply chain of the southern state of Rio de Janeiro
Autoria: ERIK TELLES PASCOAL
Resumo: With the arrival of new automakers in Brazil in the end of the 90s, the market has become very competitive and generated the need for more efficient manufacturing processes. To boost productivity, automakers have adopted the Japanese concept of monozukuri. Literally, the word means "to make (zukuri) things (mono)" and has been used to refer to manufacturing. Within the industrial context, the monozukuri also considers the process engineering activities and management of the supply chain. In this sense, the purpose of this paper is to provide a better understanding of the application of monozukuri as optimization tool of the automotive supply chain. With this goal, we conducted a survey through a closed questionnaire with different suppliers of the southern state of Rio de Janeiro. Based on the results, this paper presents a mapping of the level of application, knowledge and maturity of monozukuri projects under way in these suppliers.
2015-36-0446 || Ano de publicação: 2015
Categoria: Gestão e Desenvolvimento de Produtos
Título do Paper: Project Finance in the Automobile Industry: Proposal of the use of the Economic and Social Development Fund for the construction of technological infrastructure in the southern state of Rio de Janeiro
Autoria: VALTER SILVA FERREIRA FILHO
Resumo: The challenges posed by the global economic dynamic to the industrial sectors, particularly the automotive industry have contributed to organizations seek new alternatives to rationalize their expenditures and maximize their results in order to contribute to its sustainability and competitiveness This paper presents a case study in the automotive hub of the southern state of Rio de Janeiro about the use of the Project Finance to the creation of technological infrastructure through cooperation between different organizations with the intensive use of financial resources of the Economic and Social Development Fund (FUNDES) through its operational tool in the state of Rio de Janeiro, the RIOINVEST. This mechanism presents as a viable and attractive alternative to the automotive industry in the southern state of Rio de Janeiro and has great potential to be explored by other organizations in the State beyond the automotive industry.
2015-36-0449 || Ano de publicação: 2015
Categoria: Qualidade, Confiabilidade e Durabilidade
Título do Paper: Influence of supply voltage and fuel conductivity in the lifetime of commutation system by brushes in electric Flex Fuel pumps.
Autoria: LEONARDO YOSHIOKA
Resumo: One of the usual measures to increase the energy efficiency in automotive vehicles has been the adoption of generators with variable voltage systems, commanded by the vehicle control unit. Thus, the vehicle system voltage no longer remains constant during operation of the engine, but becomes variable as needed to charge the vehicle electrical system and better use of available engine torque. A study using the Design for Six Sigma (DFSS) methodology was performed in order to understand the influence of the supply voltage and of the fuel conductivity in the lifetime of fuel pump commutation system by brushes. Durability tests were conducted in test bench, where parameters of temperature, current draw, voltage and fuel conductivity were monitored, correlating them with the results of wear in the pump commutation system. The conclusion of the study shows how the fuel pump life varies according to the supply voltage and the conductivity of the fuel used, given that the conductivity can be affected not only by the fuel composition, but also for its quality.
2015-36-0476 || Ano de publicação: 2015
Categoria: Meio-Ambiente
Título do Paper: Theoretical Reduction in NOx Emissions Using a Torch Ignition System Operating with Homogeneous Charge
Autoria: THIAGO AUGUSTO ARAUJO MOREIRA
Resumo: The pollutants emitted by fuel burn in an internal combustion engine are harmful to health. One of undesirable pollutants are the nitrogen oxides (NOx), witch in the presence of sunlight is responsible by photochemical mist, forming products that irritates eyes, respiratory system and may damage plants. The present article aims to present the theoretical potential reduction in volumetric emissions of nitrogen oxides (NOx) in an internal combustion engine operating with the torch ignition system and homogeneous charge. Therefore, a calculation methodology based in measured pressures and determined temperatures were implemented to check the potential reduction in this pollutant emissions.The presented methodology used to estimate the NOx formation is based in NO formation model presented by TURNS. This model uses the ZELDOVICH mechanism to nitric oxide formation and were inserted an adjustment coefficient (CA) in the NO formation tax equation, in order to calibrate the model to the baseline engine operating with stoichiometric mixture. The obtained results points a potential reduction around 70% in NOx emissions.
2015-36-0477 || Ano de publicação: 2015
Categoria: Powertrain (Motores e Transmissões)
Título do Paper: Load control in spark-ignited engines possibilities: early or late intake valve closure
Autoria: WALDYR LUIZ RIBEIRO GALLO
Resumo: Abstract New devices and control techniques have been adopted to take advantage of variable valve timing properties to improve engine performance or its load control. This paper presents a study focused on the spark-ignition engine load control strategies associated with early intake valve closing or late intake valve closing. It can be shown that these load control modes can improve the indicated thermal efficiency of the engine as compared with the conventional throttle control. These strategies are sometime called Miller cycle or Atkinson cycle. A thermodynamic spark-ignition engine simulation model was employed. The advantage of a simulation model is to conduct parametric studies without the need of complex experimental apparatus. In this way, a deep understanding of the physical phenomena can be achieved and the sole effect of the desired parameter can be shown. So, general trends can be established to reduce time and money in real engine tests. The study was made for two engine speeds. Typical indicated curves are presented, as the indicated diagram and the pumping work associated with each load control strategy. The desired indicated power at a specified engine speed can be obtained with a partial closure of the butterfly valve in the intake system, or with a variable intake valve closure. It was shown that the load control using the intake valve is more efficient than the conventional throttle, since the pumping work is reduced, with a positive impact on the engine indicated efficiency. Early intake closure of the intake valve presented a somewhat better performance than late intake valve closure. Results had shown that an increase up to 7% in the thermal efficiency could be obtained for low engine speeds, and near 9% for high speed, using the early intake valve closing strategy. Late inlet valve closing strategy also presents benefits, but somewhat smaller. The smaller is the load for a given engine speed, greater are the benefits of the load control by the intake valve closure strategies as compared with the normal load control by throttling.
2015-36-0485 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: Study of wet ethanol energy balance: From production to fuel
Autoria: NINA PAULA GONÇALVES SALAU
Resumo: Various studies previously conducted have estimated the net energy value for ethanol, but the variations of data and assumptions used caused the results to lack in precision. However, studies are unanimous in pointing out that the greatest fraction of the energy necessary for making ethanol is spent in water removal (distillation and dehydration), growing exponentially the smaller the amount of water in the final product. By using wet ethanol to avoid the energy cost of dehydration, the purpose of this work were to numerically evaluate the energy spent in the distillation process and compare the results with the efficiency in using the wet ethanol used as fuel. The simulation was modelled through the Matlab® software environment, using as base a distillation column for batch process with a variable number of plates to obtain as a final product ethanol with different degrees of hydration. This final products served as four different fuel blends: hydrous ethanol fuel (HEF) and mixtures of ethanol and water in the proportions of 90% (E90W10), 80% (E80W20), 70 % (E70W30) by volume of ethanol. The energy production cost were, then, compared to the results generated by the simulation of an SI engine using each one of the fuel blends, in order to conclude if the production of a more hydrated fuel in fact contributes to a better result regarding the net energy value. A two-zone model were used for the calculations of the combustion cycle of the engine.
2015-36-0486 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Electric car and Porter’s five forces: marketing positioning in the automotive industry
Autoria: AILTON CONDE JUSSANI
Resumo: This paper determines the market positioning of the electric vehicle, while applying tools like SWOT analysis, Porter’s five forces, external environment analysis or the Ansoff’s Matrix. It is important to note that these tools are applied looking from the perspective of the electric vehicle, i.e. how is the electric vehicle impacting a conventional fossil fuel drive automobile manufacturer. There is no doubt that the electric vehicle - or at least some version of it - is the future of urban mobility. At the same time it has been considered as a new product among automotive industry. Nevertheless it cannot be neglected that the time of the electric vehicle has not come so far. It is more probable that there might be another evolution step, for example the hybrid electric vehicle, before the fossil fuel driven automobile will be replaced.
2015-36-0505 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: Curve fits for thermodynamics proprieties of butanol fuel
Autoria: NINA PAULA GONÇALVES SALAU
Resumo: Butanol is an important industrial chemical and a promising biofuel, which can be blended to higher levels without requiring engine modifications. It has lower vapor pressure than ethanol and comparable octane number, and its properties are closer to gasoline than ethanol. Prior to the advent of the petrochemical industry, which made the process uneconomic, acetone, butanol and ethanol were produced together by fermentation, using one of several Clostridia strains. With the growth in interest of biofuels and the increase in price of petrochemicals, renewable routes to butanol are being revisited by several parties. As an alternative renewable route, a traditional catalyst to convert ethanol to n-butanol with good selectivity has been studied, the so-called Guerbet reaction. Since ethanol use for internal combustion engines has been much more studied than butanol, an important lack of information is found regarding the thermodynamic and combustion parameters of internal combustion engines operating using butanol. To evaluate the combustion calculations and the thermodynamic simulation of internal combustion engines, various references from the literature can be used to obtain the thermodynamic and combustion routines. The most complete models are based on polynomials curve fits to the thermodynamic data (specific heat, enthalpy and entropy). Ferguson has used the curve coefficients found to calculate internal combustion engine in FORTRAN computational language. Heywood has represented the thermodynamic properties of selected fuels using curves that differ slightly in form to those used by Ferguson (who adopted simplified versions of the equations). Based on the FORTRAN programs for internal combustion engine calculations presented by Ferguson and using the fuel property curves of Heywood, Buttsworth has develop equivalent routines using Matlab® software. Such routines return a vector of curve coefficients for a number of different fuels. Since butanol is not listed, the goal of this study is to evaluate the coefficients of the thermodynamic property curves of butanol fuel, so that the fuel can be included in the Buttsworth routine for internal combustion engines calculations. Thus, the thermodynamic properties of butanol fuel were curve fitted to polynomials by minimizing the least-squares error using the Matlab® software and then applied in the Buttsworth routine for an internal combustion engine.
2015-36-0512 || Ano de publicação: 2015
Categoria: Materiais
Título do Paper: Methodology to Analyse Thermal and Mechanical Stresses in Friction Material
Autoria: CARLOS ABILIO PASSOS TRAVAGLIA
Resumo: In engineering development, simulation methods are frequently used to perform thermal and mechanical stress components analysis. In brake systems, where the components are exposed to mechanical and thermal loads, the numerical analysis is very helpful. Once a numerical model for brake assembly is available, it will be possible to understand the effects of successive brake applications on the temperature distribution in drum brake’s friction materials. This is a fundamental aspect to determine, for instance, the thermal stress distribution which is related to the warming and cooling of the brakes. In this work, an analytical solution to calculate stabilized temperature was used to establish a heat flux through a pneumatic S cam drum brake’s friction material applied to a numerical model in a finite element analysis. After including the effects of the riveting process and the warming in one of the 17 t bus front brake lining, areas where the stresses vary with considerable amplitudes during temperature increase were identified. The study has indicated that friction material can be submitted to cyclic loads that can cause damage accumulation. These areas have corresponded to local regions of brake linings where historically failures occur during development tests. Also, it was possible to compare results from numerical model to vehicle’s experimental data and understand its proximity to real braking events. By the application of the methodology and using the numerical model proposed in this work, it will be possible to contribute considerably for a more accurate design of the friction material.
2015-36-0513 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Influence of CFD Setup and Brief Analysis of Flow over a 3D Realistic Car Model
Autoria: RENAN FRANCISCO SOARES
Resumo: Fuel consumption of road cards has been a main issue for the global automotive industry. Engineering tools, such as wind tunnels and computational fluid dynamics (CFD), have been employed for vehicle design, intending to achieve more aerodynamic efficiency. However, wind tunnels are very expensive facilities. In this scenario, the CFD method rises as the best cost-effective tool for solution on aerodynamics. This paper presents the influences of numerics and the analysis of an intrinsic turbulent flow over a 3D realistic car model. The objective is to provide a significant cost-benefit of numerical parameters to the automotive industry in the development of road cars. Besides the validation from an unsteady-state simulation over a full car domain, the simplification of the domain by half and the steady-state regime were found to provide an acceptable approach for automotive simulation. From the point of view of turbulence, the high concentration of turbulent kinetic energy indicate regions of high instabilities as wheelhouses, mirrors, and turbulent wake with corner vortex. These regions are important for research aiming at drag reduction. Therefore, the main contributions of this paper are: (a) to present a brief discussion about the high instabilities and turbulent kinetic energy regions over the DrivAer car model, as well as (b) to outline the numerical influence on drag prediction.
2015-36-0518 || Ano de publicação: 2015
Categoria: Metodologia de Projeto e Design
Título do Paper: The Brazilian Automotive Scenario over TEN Hatch 2015 Car Models: A View from Aerodynamics
Autoria: RENAN FRANCISCO SOARES
Resumo: Since the Brazilian government established the Inovar-Auto (Programme of Incentive to Innovation and Densification of the Productive Chain in the Automobile Industry) in 2012, the automotive industry has pursued tax savings by signing up for the programme. This new policy (from 2013 to 2017) has three main objectives: protection of the industry and domestic market; increase incentives of investment and innovation; and enhance energy efficiency of vehicles produced in Brazil. For instance, manufacturers can gain up to 2% more in IPI tax credits by producing even more fuel-efficient models. In relation to energy efficiency, the aerodynamic drag over a vehicle contributes massively the share of energy requested to promote its movement. Thus, the drag forces are the major reasons of fuel consumption. In this context, this paper presents a profile comparison of Hatch 2015 cars models produced on Brazilian soil. The best-seller model of each one of the ten best-seller manufactures in Brazil are analysed. These ten Hatch 2015 models are: (1º) Fiat Palio; (2º) Volkswagen Gol; (3º) Chevrolet Onix; (4º) Hyundai HB20; (5º) Ford Fiesta; (6º) Renault Sandero; (7º) Toyota Etios; (8º) Citroen C3; (9º) Nissan March; and (10º) Peugeot 208. Therefore, the main contribution of this paper is to compare the best-seller car profiles produced and commercialised in Brazil, in a view of aerodynamic drag.
2015-36-0520 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Modeling of Battery-Bidirectional Converter Suite for PEV in concept Smart Grid
Autoria: DANIELA RODRIGUES DA SILVA
Resumo: Electric vehicles (EV) stand out as an important component in the scenario of sustainable energy and future intelligent electricity distribution systems (smart grid) due to its characteristic of non-CO2 emissions and the possibility of participation supplies chain renewable energy, among others. In the design of smart grids, contains two modes of operation for the VE in which, basically, is the charge of your battery from the grid (Grid-to-Vehicle - G2V) and using the battery as a power source for the grid (Vehicle-to-Grid V2G), in both cases, under the control of a power electronic converter DC / DC. From the literature review, this paper presents some proposals, available in the technical and scientific literature on modeling assembly DC / DC converter for battery EVs considering in connection with the distribution network and the prescribed operating modes.
2015-36-0522 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: Tailpipe Position over a Realistic 3D Road Car Model: The Effect on Drag Coefficient
Autoria: RENAN FRANCISCO SOARES
Resumo: The aerodynamic development of road car has been progressing as engineering tools become more accurate and feasible. Wind tunnels more similar to the real environment, as well as computational techniques with improved modelling and hardware, lead the development of aerodynamic applications to focus on details. In this scenario, exhaust gases may jump from ordinary residuals to useful flow for aerodynamic control. Since 2010, many F1 teams have been utilising the high heat and power of the exhaust system around the rear of the car for an aerodynamic advantage. With a lot of freedom to place the exhaust exit around the rear of the floor, Red Bull F1 team first prompted the use of exhaust gases to enhance the capabilities of the floor and diffuser area to produce more downforce. A similar concept might be applied on passenger cars. The objective of this paper is to presents the effect of exhaust gases position over the car a 3D realistic road car model on its drag coefficient. Therefore, the main contribution of this paper is (a) to present the influence of exhaust gases position over the car, as well as (b) to provide results that may support technical decision concerning performance and design targets on a road car project.
2015-36-0523 || Ano de publicação: 2015
Categoria: Gestão e Desenvolvimento de Produtos
Título do Paper: Proposal of an Aerodynamic Concept for Drag Reduction of Fastback car models
Autoria: RENAN FRANCISCO SOARES
Resumo: The automotive industry pursues to decrease the fuel consumption of road cars. As the Brazilian government, many countries around the world incentives the industry to achieve such reduction. The objective of this paper is to purpose an aerodynamic concept for drag reduction. To represent a car model, the DrivAer Fastback two-dimensional profile has been adopted as baseline. The injection and suction of momentum by a jet applied on the car rear are investigated by means of CFD. From the quantitative point of view, the suction jet on rear car profile does not seem to be a way to yield drag reduction. The injection jet at higher speed points to smaller global drag than baseline profile. Despite this positive first conclusion, the correction of drag results (removing the jet momentum from the global drag) points to higher drag of profile car than the baseline car in all three cases. On the other hand, the results from the injection of momentum at lower speed suggest a reasonable application as drag reduction system. Compared to the baseline car profile, momentum injection cases at all positions indicates drag reduction. In addition, the profile drag decreases as the jet position is higher at lower jet speed. Therefore, the main contributions of this paper are: (a) to expose that the best drag reduction has been evidenced via injection at lower speed at higher rear car position, as well as (b) offering to automotive engineering an aerodynamic concept to improve drag reduction of road cars.
2015-36-0529 || Ano de publicação: 2015
Categoria: Manufatura
Título do Paper: Vehicle SALES forecast. a statistical approach of the top ten countries in vehicle SALES.
Autoria: ALEXANDRE MANEIRA DOS SANTOS
Resumo: The overall scenario of automotive industry has required a significant effort of its steakholders. The world economy dynamism linked to costs management and the use of the best practices in manufacturing result in a centralized demand for new investments in specific countries in order to achieve the competitive advantage needed to survive profitably in this globalized market. This paper consists in develop a vehicle production forecast from mathematical and statistical models and some demand forecasting techniques regarding the top ten countries in vehicle production.
2015-36-0532 || Ano de publicação: 2015
Categoria: Veículos
Título do Paper: On the dynamics of a Belt-Tensioner with dry-friction and nonlinear spring.
Autoria: PEDRO GREGO
Resumo: This work studies the dynamical behavior of a belt-tensioner pulley, constructed with a nonlinear spring and submitted to dry-friction on the contact of the pin with an articulated arm. Friction models are addressed, and the Duffing`s equation is used to model the spring`s nonlinear behavior. A mathematical model of the belt-tensioner is presented, and the influences of friction and pre-load moment are numerically investigated. The Stick-Slip behavior of the system os also studied. It is seem that the varying normal load, the friction asymmetry and the pre-load moment can change the Stick-Slip behavior. Finally, a method is presented to map the dynamical behavior of the belt-tensioner,
2015-36-0539 || Ano de publicação: 2015
Categoria: Peças e Componentes
Título do Paper: Design of a Brake Caliper using Topology Optimization Integrated with Direct Metal Laser Sintering
Autoria: LUCAS TRAVI FARIAS
Resumo: The correct design of the brake calipers is a key factor for the safety of a vehicle. These components must be stiff enough to prevent large deformations and perform a long stroke on the brake pedal. In racing vehicles, besides a safety factor, the brake caliper must be lightweight and provide a high level of heat dissipation, ensuring a high overall performance to the vehicle. In order to improve the previous design of the brake system, the German team KA-RaceIng, from the Karlsruhe Institute of Technology (KIT), in partnership with Electro Optical Systems GmbH (EOS) developed a set of brake calipers through Direct Metal Laser Sintering (DMLS). This process uses powder metallurgy and melting by a focused laser beam to build up a component by progressive deposition of layers. The process differs from the others because it allows complex geometries and provides high relative density in the material, also being produced directly from a Computer-aided Design (CAD) and allowing excellent compromise between the desired final properties to the piece. The project was developed based on the output conditions expected in the final product, using the topology optimization software Altair`s OPTISTRUCT with subsequent computational evaluation of the model by means of Finite Element Analysis (FEA) in Abaqus and Computational Fluid Dynamics analysis (CFD) in CD-adapco. The evaluation of the final product using different boundary conditions was performed, highlighting an asymmetric final shape due the loads acting on the break caliper, an improvement in heat dissipation and a relative mass reduction.
2015-36-0543 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: An Overview of Data Transmission Used in UAVs for Remote Sensing Surveillance and Environmental Management Systems
Autoria: RODOLFO ANTONIO DA SILVA ARAUJO
Resumo: An Overview of Data Transmission Used in UAVs for Remote Sensing Surveillance and Environmental Management Systems Authors: Rodolfo Antonio da Silva Araujo (CPF 046797858-10), José Antonio Rodrigues (CPF 874971828-20), Marcelo Lopes de Oliveira e Souza (CPF 739279108-72) The increasing development of Unmanned Aerial Vehicle (UAV) technologies has allowed greater use of UAVs as remote sensing platforms to complement satellite and manned aerial vehicle remote sensing surveillance and environmental management systems. Particularly, the Brazilian National Institute for Space Research-INPE has an Environmental Data Collection System (SCD) since 1993. Recently, the MCTI (Ministry of Science, Technology and Innovation) opened the National Center for Monitoring and Early Warning of Natural Disasters (CEMADEN). Both may need additional resources for their expansions in the near future, as offered by UAV technologies. These needs illustrate the potential of UAV technologies as complement to existing or future systems. This paper presents an overview of data transmission used in UAVs for remote sensing surveillance and environmental management systems. This includes post-disaster assessment, environmental management and monitoring of infrastructure development with emphasis on imagery data communication system between the users and the aerial vehicle - link via satellite, available mobile communication networks and direct line of sight. Modulation types and allocated frequency bands for these applications are presented. These allows an image data signal captured by the surveillance camera be either displayed on the terminals in real time, or stored on ground for future off-line analysis. So, this overview aims to contribute to the expansion of current and future remote sensing surveillance and environmental management systems in Brazil using UAV technologies.
2015-36-0546 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Hydraulic system Design of a Research Sailboat
Autoria: MATEUS BERTOLIN
Resumo: Regard to the need of the Oceanography Department of the Santa Catarina University (UFSC) to have a specific watercraft for classes and research, the Mechanical Engineering Department of the same university started the ambitious project to build a 60 feet research sailboat. The watercraft shall be used to environment education classes, undergraduate and graduated students training besides professors retraining. The sailboat has to navigate in extreme conditions and it must be equipped to enter in shallow waters, mangroves and low temperatures zones. This paper presents the design of a hydraulic system to attend the specific requirements of this research sailboat. The project requires three automatized winches, one thruster, one vertical windlass and, in order to allow the sailboat to enter in shallow waters, one retractable keel. In addition, the design of the system must consider the possibility of knock over effect, which occurs when the keel has to automatically retract after hitting a submerged obstacle. This feature improves the safety and stability of the research sailboat. Due to its reliability and good weight/potency rate, hydraulic technology was chosen to actuate the thruster, winches, windlass and keel. All these actuations systems, however, have different flow and pressure requirements. In order to achieve these requirements, be energetically efficient and silent, the system is designed with two pumps. One pump is manually coupled to the main Diesel motor as the other one is coupled to an electrical motor, which turns on and off automatically. Due to this feature, the relief valve is only used in emergency situations, characteristic that reduces the power loss. A pressure reducing valve isolates the actuation systems with lower pressure requirements, allowing the same pump to supply different actuators. Nonetheless, the main aspect of this project is, undoubtedly, the retractable keel. This subsystem, considering the possibility of knock over effect, has high velocity and flow requirements. A small hydraulic accumulator is used as shock absorber, thus, the response time of the relief valve has lower effect in the cylinder movement on knock over. However, an incorrect sizing could put this feature at risk. To aid in the analysis of this issue, a free CAE software called Hopsan has been used. Another accumulator is employed as an emergency power supply in case of both diesel engine and electrical motor failures. The accumulator is sized to provide enough flow to actuate the kell once. Furthermore, the possibility and financial impacts of using biodegradable oil are analyzed.
2015-36-0547 || Ano de publicação: 2015
Categoria: Peças e Componentes
Título do Paper: Structural Analisys of support of graphite pastille for the lubrication of railway wheels
Autoria: DANIEL HIDALGO LINZMEYER DE MIRANDA
Resumo: A lubrificação adequada dos frisos das rodas ferroviárias aumenta sua vida útil, sendo assim é de fundamental importância que ocorra esta lubrificação para a redução dos custos envolvidos na manutenção ferroviária. Este trabalho teve como objetivo avaliar estruturalmente um suporte de pastilha para a lubrificação de rodas ferroviárias. Para a elaboração desta avaliação foi utilizado à Norma Ferroviária Europeia (International Electrotechnical Commission - IEC 61373), a qual estabelece quais os carregamentos que devem ser aplicados a este componente. Os carregamentos aplicados sobre o suporte, de acordo com a norma IEC, são acelerações randômicas e acelerações devido a choques, simulando assim as condições que existe ao longo do percurso do trem. As análises estruturais foram realizadas através do método de elementos finitos, com o auxílio do software Cosmos. Desta forma, foi possível realizar a determinação das tensões atuantes no suporte, e assim comparar com as tensões admissíveis propostas pela norma AISC (American Institute of Steel Construction). As tensões obtidas nas análises estruturais foram inferiores aos admissíveis considerados, portanto, para a configuração apresentada, não são esperados problemas estruturais.
2015-36-0549 || Ano de publicação: 2015
Categoria: Eletro-Eletrônica e Eletrônica Embracarda
Título do Paper: OCCUPANCY RATE INSIDE MOTOR VEHICLES USING WIRELESS SENSORS NETWORKS
Autoria: WENDLER AUGUSTO ZACARIOTTO
Resumo: This work aims the implementation of a system able to estimate the occupancy rate (number of occupants) inside motor vehicles. This system is based on an Wireless Sensors Network using the standard IEEE 802.15.4, connected to a computer. The estimation of occupancy rate inside the motor vehicle can provide better energy efficiency and therefore optimize fuel and battery consumption.
2015-36-0550 || Ano de publicação: 2015
Categoria: Combustíveis e Recursos Energéticos
Título do Paper: EVOLUTION OF SPECIFIED FEATURES IN THE BRAZILIAN ETHANOL
Autoria: GILSON RODRIGO DE MIRANDA
Resumo: Analytical requirements for anhydrous and hydrous ethanol are set in Brazil since 1979 by means of CNP RESOLUTION No. 8, OF 03/06/1979 - of the National Petroleum Council (NPC). At the time, ten characteristics were specified for fuel: DENSITY 20ºC; Alcoholic content; FIXED residue; TOTAL ACIDITY; ALDEHYDES; ESTERS; HIGHER ALCOHOLS; COPPER; Alkalinity; Appearance. In 1981, by the issuance of CNP RESOLUTION No. 13, OF 08/18/1981 - , no significant changes were made. In RESOLUTION No. 7, DE 08.10.1982, the EVAPORATIVE RESIDUE parameter was aggregated to those previously described. Widely studies were carried out in the early 80s, by public and private research institutions in 1986 - RESOLUTION No. 10, OF 05/12/1986 – which presented innovations in the Brazilian specification. The following characteristics were inserted: GASOLINE CONTENT; ALCOHOLIC CONTENT UP TO 30 mL/L GAS; Density at 20ºC up TO 30 mL/L non volatile materials at 105ºC; Evaporative Residue ELECTRICAL CONDUCTIVITY; Hydrogen ionic potential; METALS (IRON AND SODIUM) and anions (SULFATE AND CHLORIDE). The following characteristics were excluded: FIXED residue; ALDEHYDES; ESTERS; HIGHER ALCOHOLS and alkalinity. In 1991, with the publication of RESOLUTION No. 23, OF 29/10/1991, as issued by the National Fuel Department (DNC), some changes were made: Parameters Wordings and removal of chloride. The first specification issued by the National Petroleum Agency (ANP) was published on 19.3.2001, RESOLUTION No. 45, OF 16.3.2001, with the following changes: Wording changes insertion of CHLORIDE; insertion of COLOR and alcoholic content amendment to the wording of GASOLINE CONTENT (content of hydrocarbons, max), Density at 20 ° C (up to 3% by volume of hydrocarbons) and ALCOHOLIC CONTENT (up to 3% by volume of hydrocarbons), naming ALCOHOLIC when free hydrocarbons. In RESOLUTION No. 2, OF 16.1.2002 - 17.1.2002 DOU, the description "with up to 3% by volume of hydrocarbons" was withdrawn from the text for Density at 20ºC. Naming ALCOHOLIC was unified in that order. With the publication of RESOLUTION ANP No. 126, OF 8.8.2002 - 9.8.2002 DOU and ANP No. 36, OF 6.12.2005 - 7.12.2005 DOU there was no change in the technical regulation. In 2011, some features have been added: WATER CONTENT, CONTENT OF METHANOL AND GUM WASHED. The parameters related to ions had the addition of the word "CONTENT". Given the worldwide leading position of Brazil in the production of ethanol and the need to establish a change in historical characteristics, and their limits, we propose a technical survey of the evolution of Brazilian Ethanol specification - containing the following approaches for each feature: Evolution of regulation in Brazil; Important feature of the specification; Fuel Quality Data analysis and/or production data analysis; National and international standardization; International amendment prospects.
2015-36-0551 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: An Overview of Multi-Paradigm Modelling and Simulation
Autoria: LEONARDO LEITE OLIVA
Resumo: Throughout the years, modelling and simulation (M&S) are becoming important enablers in the analysis and design of complex systems. In order to tackle problems that are becoming more complex, M&S research is shifting from simulation techniques to modelling methodology. The primary goal of this new enterprise is the unification of different M&S concepts, methods and techniques. Multi-paradigm modelling is a broad field of research and development that integrates three lines of research: 1) multi-formalism modelling, concerned with the coupling and transformation between models; 2) model abstraction, concerned with the relationship between models at different levels of abstraction; and 3) meta-modelling, concerned with the description of classes of models. This work presents an overview of multi-paradigm modelling used in highly integrated systems. This includes research and developments made abroad and an example of a study conduced at INPE comparing two different M&S approaches and tools used to validate a satellite propulsive subsystem. The analysis of this example and the international evolution towards a new approach and methodology in the field of M&S allows us to identify some trends that could be adopted in several industry niches that deal with integrated systems of different domains, from cyber-physical components to global economies.
2015-36-0553 || Ano de publicação: 2015
Categoria: Qualidade, Confiabilidade e Durabilidade
Título do Paper: A Discussion on the Methods of Thermal Cycling and Power Cycling for Reliability Prediction of Solder Joints of Electronic Components
Autoria: ALIRIO CAVALCANTI DE BRITO
Resumo: The increasing use of embedded electronics in aerospace and automotive vehicles increases the designers` concern regarding the reliability of the components as well as the reliability of their interconnections. The discussion about the most appropriate method for assessing the reliability of solder joints for a given application is an ever-present theme in literature. Several methods of prediction have been developed for assessing the reliability of solder joints. The standard method established by the industries for assessing reliability of solder joints is the thermal cycling. However, when the thermal distributions in real applications are studied, particularly in some electronic components used in on-board electronics of space systems, the thermal cycling does not represent what actually happens in practice in the packaging. The aim of this article is to discuss the methods of thermal cycling; and power cycling for reliability prediction of solder joints of electronic components. With the power cycling you can: 1) simulate more closely the actual conditions; 2) accelerate a cycle of application when applying energy to the component, increasing junction temperature; and decreasing the junction temperature when removing energy from the component. With the thermal cycling, the solder joints and the printed circuit board are almost at the same temperature in an isothermal situation at any moment and thermal gradients within the packaging are often negligible. Fatigue data of solder joints from thermal cycling and power cycling are obtained through networks of monitoring components of type "daisy-chain" with the aid of high-speed event detectors. Both profiles are obtained and compared in the Weibull graphs. Failure data results obtained from the literature have shown that the thermal cycling in general is conservative compared with the power cycling. In addition, according to the literature, power cycling simulates better the gradients of temperature found in the packages of components in actual applications. On components of type PBGA, solder joint characteristic life was 45% longer in power cycling.
2015-36-0560 || Ano de publicação: 2015
Categoria: Ruídos e Vibrações (NVH)
Título do Paper: Advantages of directive acoustic sources for audible alert systems in electric vehicles
Autoria: JUAN J. GARCÍA
Resumo: Advantages of directive acoustic sources for audible alert systems in electric vehicles García, Juan J. Applus IDIADA Group, Spain KEYWORDS – Electric, Vehicle, Pedestrian, Alert, Detection, EV, Sound ABSTRACT The rapid growth of Electric Vehicles (EV’s) and Hybrid Electric Vehicles (HEV’s) has increased the concern that the relative silence of EV`s will result in an increased risk to pedestrian safety. A practical solution to this problem is to add artificial sounds to EV`s to aid their detection by pedestrians and other vulnerable road users. Acoustic warning systems for EV’s should increase pedestrian safety and simultaneously produce a small impact on environmental noise levels. This paper shows the main advantage of using a directive acoustic source implemented as a beamforming loudspeaker array in an EV to increase pedestrian safety and control the effect on noise pollution. An example of such a system has been implemented in a Nissan Leaf vehicle and its performance in realistic situations has been assessed. The experimental results show that this type of approach is very effective to increase close-to-accident pedestrian safety near EV’s and, simultaneously, reduce noise pollution with respect to conventional acoustic warning devices.
2015-36-0561 || Ano de publicação: 2015
Categoria: Metodologia de Projeto e Design
Título do Paper: A proposed process for structural reliability analysis of automotive components
Autoria: ANTONIO CARLOS CARVALHO NASCIMENTO FILHO
Resumo: In design of automotive structural components is common scaling of the data for the "worst case", i.e. a condition of the component of least resistance (stress) and maximum load conditions applied (strenght). However, in a real situation, it is not possible to determine with absolute certainty these amounts due to the random nature of the parameters involved. Thus, this design should be treated in a probabilistic way, where the parameters involved could be considered as random variables, and the project could be qualified for a desired condition of reliability. Thus, stress and strenght would be described by probability distribution functions that would intersect and generate an stress – strenght interference. This paper presents a proposed process (flowchart) for performing computational experiments for reliability analysis in automotive structural components when subjected to an stress - strenght interference. The process showed itself as able to identify the most adequate method of reliability prediction to solve problems of stress - strenght interference in a design of a structural automotive component. Key - words: Structural reliability automotive; interference stress - strenght, FOSM/FORM / SORM, Monte Carlo Method; MARS;
2015-36-496 || Ano de publicação: 2015
Categoria: Testes e Simulações
Título do Paper: Matlabdss framework for Stochastic Simulation for Voltage Harmonic Distortion Analysis Derived From Electric Vehicles Charging, Applying Monte Carlo Method
Autoria: RODRIGO ASSIS BONFIM
Resumo: Este trabalho apresenta um ambiente para a simulação estocástica visando à análise de distorções harmônicas de tensão provenientes do carregamento de veículos elétricos na rede de distribuição de baixa tensão, utilizando os softwares OpenDSS e Matlab de forma integrada. A simulação de Monte Carlo é empregada para a geração de vários conjuntos de amostras aleatórias do estado de carga (SOC – State of Charge) de cada um dos veículos elétricos em ambiente Matlab, considerando-se que essas amostras sejam estatisticamente independentes e uniformemente distribuídas. Posteriormente, baseado em um perfil de carga reportado na literatura, são calculadas as correntes harmônicas geradas por cada veículo. No OpenDSS é, então, calculado o fluxo de potência harmônica, sendo possível, dessa forma, a determinação da distorção harmônica total em cada barra do sistema de distribuição. Por fim, são definidos e discutidos cenários de simulação levando em consideração a quantidade de veículos elétricos conectados à rede.