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Gasoline direct injection (GDI) engines have very attractive potential for improving fuel economy and exhaust emissions, especially 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.

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.

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.

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.

The purpose of this paper is to present the origins and the technology of the different types of non-manual transmissions systems currently available and the wide potential to incorporate such technologies to the vehicles made in Brazil. The Brazilian market is experiencing a huge increase in automated and automatic transmissions vehicles share, and the OEMs are adopting 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 point out the pros and cons of each one.

Current massive urbanization process concentrates high amount 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.

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 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%.

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 automakers pursue for fuel economy is increasing year after year, both by the demands of society and by political pressures, leading companies to develop new solutions and technologies in order to increase the energy efficiency of vehicles. With the advent of CFD software, it is possible to study drag reduction proposals, which contributes to increase fuel economy. In this context, based on a small sedan vehicle virtual drag model, correlated with the wind tunnel test, a conceptual wheel was assembled proposing 3 blade angles in order to verify the influence on the drag coefficient. Considering the drag contribution of wheel in total vehicle drag is around 25%, this work aims to show the sensitivity in the drag coefficient by changing the wheel rim of a small sedan vehicle.

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.

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 researched, 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, Aluminum Alloy, Magnesium Alloy, Hybrid Material and Polymer Composites.

This paper aims present information regarding Automotive Body in White (BIW) 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 properly revision regarding applied loads, body in white materials, safety and virtual/physical validation will be covered. Structural fundamental knowledge has a key role of Design Engineer background mindset to achieve challenges vehicle targets about cost, mass and performance. The paper information provides a clear technical reader understanding how product engineers use structural fundamental theories to design BIW in real design development application. A study of case regarding Front-end tie-bar was used. A real vehicle load application was simulated by CAE analysis.

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, electrochemical hysteresis, effects of temperature, state of charge and state of health.

Object-oriented programing has been around for more than 50 years and has changed the way we develop computational algorithms. Although the concept of objects in programming was introduced with a physical systems modeling tool, most modelling is done today with procedural programming. This paper aspires to show the benefits of object-oriented programming in contrast to procedural programming. This was done by taking a case study in which we analyze the model of the vehicle electric system. The system was partially modelled using Simulink for procedural programming and using Simscape for object-oriented programming. As a result, the object-oriented model was simpler to read and understand. It also provided an interface that facilitates expansion, whereas the procedural model needed to be rebuilt to accommodate changes in the structure and presented higher complexity.

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.

The union of parts by using bolts is one of the most used, which combines versatility and low cost, and the failure of a single bolt can cause failure of the entire structure or machine. Several factors influence the effectiveness of these bolted joints, including the material of the washer. 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 assembly torque, 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 your fatigue life. The use of numerical simulation using the finite element method makes it possible to change the model variables, such as the geometry and materials of the components.

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 couples the dynamic characteristics of the crankshaft and 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 as hybrid simulation, which consists in the solution of the dynamics of an Elastic Multi-Body System (E-MBS) coupled with the Finite Element Methodology (FEM). 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 PROCONVE (MAR-I) emission regulations.

In the field of engineering, there is a well known phenomenon called “stick-slip” a specific type of vibration in a mechanical system where friction is involved, it is qualified as non-linear, auto-excited and generally stable within a limited cycle. During stick-slip, the behavior of the friction coefficient as a function of the sliding velocity has big influence on the wave pattern, wherein various models can be found in the literature. Besides affecting wave patterns, this behavior affects significantly the amount of damping necessary to reach an asymptotic level of stability. The objective of this work is to study various friction models found in literature, for example: constant transition between coefficients, linear and exponential and apply these models in mechanical systems that represent brake systems.

The effects of specific parts inside the vehicle body in a radiated immunity numerical simulation is addressed. The benefits of numerical simulations for electromagnetic compatibility analysis is well known and reported in the literature, nevertheless, the accuracy of the results depends on the mathematical models that is being considered. Numerous simulations were performed, detailing how specific parts of a vehicle can affect the electric field inside a vehicle. The commercial package ANSYS HFSS™ was used due to the extremely fast and accurate simulations since it uses the finite element method technique, which includes hybridizations with the method of moments. This allows full simulations to be performed in a few minutes with controlled convergence, allowing a more extensive investigation. Simulation results are compared with experimental data obtained from experiments performed at Instituto Nacional de Pesquisas Espaciais showing a good agreement.