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The current paper addresses the comparative analysis of the performance (friction and wear) produced by original and aftermarket brake pads. The brake pads selected in this study belongs to a large circulation vehicle in Brazil, which also has a high number of sales. An original and 4 others aftermarket brake pads were purchased at Porto Alegre, Brazil. The braking tests were performed on a braking tribometer, which is located on the University facilities. Experimental data of the coefficient of friction produced by each brake pad have been recorded. A precision scale was used to measure the mass loss of the materials subjected to the tests. Results of the performance obtained by the brake pads are evaluated and discussed in this paper. Results have shown that the original brake pad has superior properties in terms of friction performance (magnitude and variation), while aftermarket 1 and aftermaket 2 materials have the lowest vibration magnitudes.

In commercial vehicles which generally have large capacity fuel tank, sloshing of fuel and its effect on the tank structure is very important aspect during fuel tank design. Dynamic pressures exerted by the fuel on baffles, end plates and tank shell during sloshing can lead to structural failures and fuel leakage problems. Fluid structure interaction simulation of automotive fuel tank sloshing and its correlation with physical test is demonstrated in this study. During physical sloshing test of 350 L fuel tank, cracks were observed on center baffle and spot weld failures developed on fuel tank shell. Same sloshing test was simulated for one sloshing cycle using fluid structure interaction approach in LS Dyna explicit FE solver. Water was used instead of fuel. Mesh free Smoothed Particle Hydrodynamics (SPH) method is used to represent water as it requires less computational time as compared to Eulerian or ALE method.

For many years, all Side Impact Crash Test studies have been put into practice considering the results achieved from the EuroSID II dummy. The introduction of the WorldSID to the crash test world has become a milestone not only for vehicle manufacturers but also for crash test laboratories. Because of this, it is necessary to study the differences between the EuroSID II and the new dummy to be used from now on in Euro NCAP Side Impact Tests, the WorldSID. To do this, an in-depth analysis of the structure of both dummies was carried out so as to obtain a clearer view of what can be expected of the values achieved from testing them. Furthermore, a series of impact tests were defined, based on side impact virtual tests, making a special effort to obtain crash test results from both dummies in very similar configurations.

The engine research and development has a significant contribution to meet the stringent emission norms and the changing global market demands. Leveraging the available virtual engineering methods to improve performance, velocity, quality and diminish the lead time is the key for any global brand to stay in the competition. It is the key element to reduce the research and development costs substantially by virtually developing the idea as it is conceived. Engine development test cells consist of expensive test and measurement systems which demand skilled labor and advanced equipment. Effective utilization of the test cells is essential to meet the scheduled project deadlines and cost targets. Engine Design process and tools when used effectively can increase the efficiency and lower the test cell operation costs substantially. This paper discusses the examples for this application in the area of engine installation, sensitive instrumentation/assembly.

During the conceptualization of vehicle, it is big challenge for automotive manufacturer to design a vehicle which has an excellent aesthetic looks as well as meet the stringent vehicle regulations. In the vehicle styling, bumper plays an important role in deciding of the contemporary looks of the vehicle. To improve customer satisfaction, it is important to design a bumper which provides feeling and sense of durability. In addition, bumper should sustain low-speed impact and protects the peripheral components such as parking lights, headlamps, hood, back door and safety related installed equipments like Rear parking camera, parking sensors, etc. Bumper should be dent resistant and be able to regain its original shape on removal of the applied load. An elegant design of bumper should be light weight with high strength. This paper explains about a new CAE methodology developed to simulate the real life loading condition of bumper and to calculate the deformation in the bumper.

The tire is generally characterized on the basis of forces and moments being generated at the contact patch, which describes the friction potential of the tire in both longitudinal and lateral directions at different load conditions. The field conditions and applications under which the tires (especially commercial one) perform is diverse, which results in varied performance for the same product. To understand this there is a need to recognize the range of friction values the tire undergoes in different conditions. Though there are couple of methods and indoor test available to estimate the available friction potential, they are not only deficient in replicating the different real road scenarios but also prove difficult to reproduce different road surfaces. There is also a lack of availability and expense of out door test equipment in India.

BIW (Body-in White) is a type of vehicle structure formed by spot welding of different sheet metal components. The BIW structure should be designed to support the maximum load potential under various performance conditions. Thus the structure should have good strength as well as stiffness. Torsion Stiffness of BIW is the amount of torque required to cause a unit degree of twist. It is often considered as a benchmark of its structural competence due to its effect on various parameters like ride, handling, lateral load distribution and NVH performance of vehicle. The paper aims to design and develop a test methodology and test fixtures for measuring the BIW torsion stiffness with repeatability of test results and also have an (R2>0.99) for the measured values in the test.

An automobile rear view mirror is attached at the side of the vehicle which is used to provide clear vision outside the vehicle. In the running condition of vehicle, various vibrations occur and are transferred to the mirror which may disturb driver's rear view. Since the vibration of mirror is related to safety consideration, it becomes essential to minimize it. Vibration analysis is very much important for the successful design and development of new parts in automobile. In present work, Vibration analysis of existing design of outside rear view mirror is investigated through numerical model using Finite Element Method (FEM). Furthermore, these results are verified through experimental work. From the modal analysis, it was found that the natural frequency of outside rear view mirror is less than the excitation frequency (Engine & Road excitation). However, to avoid resonance and for a safe design the natural frequency must be greater than these excitation frequencies.

This paper presents a methodology for predicting thermal comfort inside Midibus cabin with an objective to modify the Heating, Ventilation and Air Conditioning (HVAC) duct design and parametric optimization in order to have improved thermal comfort of occupant. For this purpose the bus cavity is extracted from baseline CAD model including fully seated manikins with various seating positions. Solar Load has been considered in the computational model and passenger heat load is considered as per BSR/ASHRAE 55-1992R standard. CFD simulation predicted the air temperature and velocity distribution inside passenger cabin of the baseline model. The experimental measurements have been carried out as per the guidelines set in APTA-BT-RP-003-07 standard. The results obtained from CFD and Experimental test were analysed as per EVS EN ISO7730 standard and calculated occupant comfort in terms of thermal comfort parameters like Predicted Mean Vote (PMV) and Predicted Percentage Dissatisfied (PPD).

The paper contributes to the field of vehicle safety technology by the virtual approach using biomechanical virtual human body models. The goal of the paper is to exploit the previously developed scaling algorithm to create several virtual human models of a given age and body proportions and to assess the impact analysis using the sensitivity approach. Based on a validated reference model, the previously developed scaling algorithm develops virtual human body models for given height, mass, age and gender. Particular body segments are scaled based on the anthropometrical database concerning the body dimensions taking also percentiles into account. The body stiffness is driven by age dependent flexindex. Several virtual models of human bodies representing particular cadavers were generated via the automatic scaling algorithm. The frontal sled test response of three models was successfully compared to the available experimental data previously.

The main purpose of this paper is to research the aerodynamic characteristics of the Formula SAE car. A more accurate CAD model is built to reduce the impact of oversimplification. Computational Fluid Dynamics (CFD) method is adapted. The computational domain is meshed with tetrahedral and polyhedral cells and the flow field is predicted using the Realizable k - ε turbulence model. Data obtained in this study include the aerodynamic drag and lift coefficients, pressure distribution on external surfaces and velocity distribution at different cross sections. The pressure distribution is investigated in a quantitative manner. An in-depth study is undertaken to analyze the turbulence structure in the wake. The research indicates that the front and rear wings have a notable impact on the external aerodynamics of the car. Furthermore, several suggestions are put forward to make the Formula SAE car achieve higher levels of performance.

Cooling system is one of the important systems of an engine to maintain the optimum coolant temperature across engine and its components. Analysis of cooling system at initial phase of product development will help in optimum design of the system and there by achieving better performance of engine. For this purpose the traditional method followed is to run several bench tests and to analyze the engine performance and repeat the bench tests for validating any design changes. This results in increased lead time of engine development and overall cost. To reduce the lead time as well as reduce the overall cost, 1D (one dimension) simulation tools place a major role. Simulation of engine cooling system with special kind of engine coolant water jacket is challenging. It is difficult to achieve the simulation results close to bench test due to complexity of the system.

The Charge Air Cooler (CAC) is designed to cool the charge air after being boosted by the Turbocharger. In order to maintain the optimum temperature and to further improve the charge air density entering to the engine the CAC is used. This makes the combustion more efficient and better engine performance and fuel economy. The performance of the CAC is highly affected by the plumbing lines which transport the compressed charge air from turbocharger to the intake manifold of the Engine. It consists of tube, hose, duct and resonator. Designing the optimum CAC plumbing lines with lesser pressure drop is the major requirement of the CAC system considering the complex packaging. In such scenarios, one-dimensional (1D) simulation is a good way to compute the pressure drop for faster and economical solution.

An expansion tank is an integral part of an automotive engine cooling system. The primary function of the expansion tank is to allow the thermal expansion of the coolant. The expansion tank will be referred as hot bottle in this paper. In the System level modeling of the engine internal flow, it is imperative to accurately model and characterize the components in the system. It is often challenging to define the hot bottle accurately with limited parameters in the 1D modeling. Currently it is very difficult to optimize the system by testing. Since testing consumes a lot of time and changes in development stage. If the hot bottle component is not defined properly in the system network, then the system flow balancing cannot be predicted accurately. In this paper, the approach of creating a 1D modeling tool for hot bottle flow prediction is discussed and the simulation results are compared with the physical test data.

With a significant increase in awareness of safety and sustainability among the automobile original equipment manufacturers and end users, every car manufacturer is looking for lightweight, safe and cost-effective solutions for every unit present in their vehicle. The latter gets much more focus in developing countries, where the automobile market is extremely cost sensitive. Further, with implementation of the proposed global technical regulations on pedestrian safety in the near future and low-speed vehicle damageability requirements, demand for a low-cost, lighter and safer bumper system is ever increasing. This paper focuses on development of a unique thermoplastic energy-absorbing device for vehicle bumpers. Conventionally, major energy absorbing members of these bumper systems consist of three separate pieces: energy absorber, bumper beam and crash cans. A hybrid approach based on logical reasoning and topology optimization is used to conceive the design.

There is a growing need for improved conceptual vehicle designs along with alternative materials to reduce the damage to the passengers and structures in aerospace and automotive industries. The energy absorption characteristics of materials play a major role in designing a safe vehicle for transport. In this paper, compression behavior and energy absorption of aluminum alloy AA6061 and AA7005 tubes in T4 and T6 conditions are investigated by experimental and numerical methods. The AA7005 and AA6061 tubes are solution heat treated and then aged to achieve the final strength in T6 condition. Experimental compression test results have shown improved energy absorption of tubes in T6 condition compared to tubes in T4 condition. There is less variation of energy among the tested samples. The mean load is compared with the results obtained from analytical formulae. Tensile properties have been obtained from tensile tests using UTM for both AA6061 and AA7005 tubes.

In order to speed up engine coolant warm-up, the exhaust heat recirculation system collects and reuses the heat from exhaust gases by utilizing the heat exchanger. The conventional system improves actual fuel economy at the scene of the engine restart in winter season only. The heat recirculation system becomes more effective at the low outside temperature because it takes longer time to warm up engine coolant. However, the heat recirculation system becomes less effective at the high outside temperature because it takes shorter time to warm up engine coolant. Therefore, the new exhaust heat recirculation system is developed, which adopted as follows: 1) a fin-type heat exchanger in order to enhance exhaust recirculation efficiency 2) a thinner heat exchanger component and smaller amount of engine coolant capacity in the heat exchanger in order to reduce the heat mass As a result, the actual fuel economy is more improved in winter season.

The use of smart portable devices in vehicles creates the possibility to record useful data and helps develop a better understanding of driving behavior. In the past few years the UTDrive mobile App (a.k.a MobileUTDrive) has been developed with the goal of improving driver/passenger safety, while simultaneously maintaining the ability to establish monitoring techniques that can be used on mobile devices on various vehicles. In this study, we extend the ability of MobileUTDrive to understand the impact on driver performance on public roads in the presence of distraction from speech/voice based tasks versus tactile/hands-on tasks. Drivers are asked to interact with the device in both voice-based and hands-on modalities and their reaction time and comfort level are logged. To evaluate the driving patterns while handling the device by speech/hand, the signals from device inertial sensors are retrieved and used to construct Gaussian Mixture Models (GMM).

This paper describes the Common Automobile Program (CAP) that can be implemented to improve mass transportation. CAP is the use of automated electric vehicles using smart navigation and control technologies to improve mass transportation. In CAP, common vehicles are used by different passengers, thus, reducing the on-road traffic and also the parking space required. Various low-cost stations are to be built along specified paths and the vehicle can be used at the convenience of the commuter. Currently, buses and trains require the passengers to wait at the station and a significant amount of time is spent at intermediate stops. The vehicle in CAP runs directly from origin to destination and also eliminates the waiting time at stations. Passengers do not wait for vehicles; instead vehicles wait for the passengers. The journey starts as the passenger enters the station and selects the destination.

This paper reports an effort to improve plan of vehicle trajectory using an approach with rapidly-exploring random trees (RRT), which has been widely adopted in the prior art for complex and dynamic traffic environment. Design and implement of an integrated threat assessment is presented that evaluates threats of the trajectory. A node and trajectory evaluation index was introduced into the proposed RRT algorithm to connect an appropriate node and select the best trajectory. The contribution of this paper is on the threat assessment that takes into account not only obstacle avoidance but also stability. The simulation is conducted and the results show that the proposed method works as expected and is valid and effective.