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A general automotive car is majorly composed of high strength steel (6%), other steel (50%), Iron (15%), Plastics (7%), Aluminum (4%) and others (Rubber, Glass, Textile) about 18%. End-of-life vehicles (ELVs) are a significant source of waste and pollution in the automotive industry. Recycling ELVs, particularly their plastic components, Li-ion batteries, catalytic converters, and critical technology components such as alternators, semi-conductor chips, and high tensile strength steel can reduce their environmental impact and conserve valuable raw materials. The paper conducts a SWOT analysis and a life cycle assessment (LCA) to evaluate the long-term viability and potential of ELV recycling, environmental impact, and carbon footprint.

In automotive Front End Accessory Drives (FEAD), the crankshaft supplies power to accessories like alternators, pumps, etc. FEAD undergoes forced vibration due to crankshaft excitation, dynamic tension fluctuations can cause the belt to slip on the accessory pulleys. By considering the criticality of the system, when engine mounting is longitudinally to the vehicle which makes it directly exposed to the air flow containing foreign particles which may cause the damage to the FEAD system and deteriorate the intended functionality. FEAD cover is introduced in the system to enhance belt-pully system functionality by restricting the entry of foreign particles during engine operation. This paper contains a study of FEAD cover failure and provides the stepwise approach to capture such issue during novel model development for 4 cylinder naturally aspirated engine during engine bench testing.

Automobile exhaust systems help to attenuate the engine combustion noise as well as the high frequency flow noises which are generated as the gas expands and contracts through various ducts and orifices of muffler system. One of the solutions to mitigate the noise generated due to the latter is by means of an absorptive muffler, comprising a fibrous acoustic medium which helps to absorb noise of certain frequencies which are sensitive to the human ear. Typically, the construction of such a system consists of the fibrous acoustic medium encompassing a perforated inner pipe on the inside and enclosed by an outer metal case on the outside. The temperature limitations of the acoustic medium sometimes necessitate the placement of the fibrous acoustic system away from the engine source in order to prevent any damage to the fibers upon direct contact with the flue gas.

With the increasing competition in the automotive industry, customer experience & satisfaction is at the top of every organization's goals. The customers have evolved & NVH refinement has become the parameter for their decision making in buying a car. The major source of rumble noise in a vehicle is the induced vibrations due to combustion forces in an IC engine. These vibrations are then transferred to the vehicle body through engine mounts. Hence engine mounts play a key role in defining the NVH & the ride performance of any vehicle. However, it is infeasible to validate every mount design through the physical test as it will be both costly & time-consuming. But multiple design iterations can be verified by the CAE approach quite effectively. This paper focuses on the novel CAE approach to evaluate the mount vibrations due to engine dynamics. The process involves preparing a FEA model of the complete Powertrain system.

Valve train system is one major contributor to engine overall friction loss and is approximately 30% of total engine friction at lower speed and approximately 20 % at higher engine speed. Valve spring loads (preload and working) are proportional to friction loss of valve train. To optimizing the valve spring design main requirement is valve train perform it function safely at maximum engine cutoff RPM with minimum preload and working load. Robustness and frictional power loss are contradicting requirement, robustness demand high stiffness spring for better valve jump and bounce performance with dynamic safe valve spring design, on the other hand low frictional power loss demand for use of low stiffness spring. To optimize the valve spring stiffness for meeting both the requirement we need accurate prediction of valve spring in design stage and good correlation with testing data to reduce the number of iterations.

Radiators are one of the major components in the automotive engine cooling system. The road excitations from the frame to the radiator are dampened using rubber bushes. In this work, we analyzed a radiator sub-assembly with bushes by applying acceleration which are recorded at the center of gravity of the radiator. The radiator is considered as the concentrated mass which is attached to the upper and the lower radiator tank which is further connected to the frame through the bushings. An implicit transient dynamic analysis is set up. The hyper elastic coefficients for EPDM rubber are determined using the experimental data fit and structural damping coefficients are applied. When excited by the acceleration applied at center of the radiator component, the rubber bushes are deformed severely. Moreover, the analysis shows high strains in certain location on the upper bush where the part showed actual failure in the testing.

In view of global concern for greenhouse gas emissions, need for greener and efficient Engines is increasing. Hence is it imperative that Internal Combustion Engines are improved in terms of efficiency to reduce Greenhouse gas emissions and meet CAFE targets. The cooling system of an ICE plays a major role in a vehicle performance. In this system, the radiator, thermostat, and cooling fan are the main components. Conventional cooling system uses Wax-type thermostat which is activated at specified coolant temperature and maintain same coolant temperature in fully warmed up condition at all engine operating points. Operative temperature selection in Wax-type is trade-off between engine friction & thermal efficiency at lower loads & knocking at higher loads. An electronic thermostat is a good alternative to maintain optimum temperature as per operating point requirement since optimum temperature at different operating points can be different.

Over the years, Fuel efficiency and cabin comfort of vehicle has become increasingly important in buying decision and can significantly give competitive edge to the vehicle in marketplace. Weight and friction reduction of rotating and reciprocating components in engines is one of the proven approaches to improve the efficiency of internal combustion engine. To reduce the friction, the general approach is to use low viscosity engine oils, improve the surface finish and reduce the contact area of sliding elements, switch over from sliding contact to rolling contact etc. However sometimes this approach has adverse impact on engine NVH characteristics due to occurrence of abnormal transient noise due to mechanical knocking of the components in specific operating conditions.

With advancement of technologies, upgradation of validation procedures and equipment on engine dynamometer test bed is required to simulate environment similar to vehicle and achieve accurate test results. A coolant conditioning system helps in achieving desired temperatures of coolant in the circuit during engine validation. However, unlike radiator type cooling systems of vehicles, conventional coolant conditioning systems on engine test beds generate negative pressure in circuit which poses a risk of coolant boiling, loss of intended heat transfer and hence higher temperature in cylinder head which can be detrimental for durability of critical components like valves, valve seats etc. This paper encompasses a stepwise approach followed to attain near-vehicle coolant pressure conditions for a naturally aspirated engine. Coolant used for this experiment was 50:50 (by volume) ethylene glycol and water mixture.

In order to meet the challenges of future CAFE regulations & pollutant emission, vehicle fuel efficiency must be improved upon without compromising vehicle performance. Optimization of engine breathing & its impact on vehicle level fuel economy, performance needs balance between conflicting requirements of vehicle Fuel Economy, performance & drivability. In this study a Port Fuel Injection, naturally aspirated small passenger car gasoline engine was selected which was being used in a typical small passenger car. Simulation approach was used to investigate vehicle fuel economy and performance, where-in 1D CFD Engine model was used to investigate and optimize Valve train events (Intake and exhaust valve open and close timings) for best fuel economy. Engine Simulation software is physics based and uses a phenomenological approach 0-D turbulent combustion model to calculate engine performance parameters. Engine simulation model was calibrated within 95% accuracy of test data.

In the recent years world-wide automotive manufacturers are continuously working in the research of the suiTable technical solutions to meet upcoming stringent carbon dioxide (CO2) emission targets, defined by regulatory authorities across the world. Many technologies have been already developed, or are currently under study, to meet the legislated targets. To meet this objective, the generation of tumble at intake stroke and the conservation of turbulence intensity at the end of compression stroke inside the combustion chamber have a significant role in the contribution towards accelerating the burning rate, increasing the thermal efficiency and reducing the cyclic variability [1]. Tumble generation is mainly attained by intake port design, and conservation is achieved during the end of compression stroke 690 ~ 720 crank angles (CA) which is strictly affected by the piston bowl geometry and pentroof combustion chamber shape.

In a Passive suspension, a shock absorber generates damping force by pressurizing the oil flow between chambers. Typically, vehicle responds with suspension deflection, which significantly depends on damping forces and suspension velocity. Tuning dampers for various roads and steering input is an iterative balancing process. In any setting, damping force w.r.t velocity is tuned for optimum ride and handling performance. Practically, to achieve a balance between the two is a tedious task as the choices & arrangements of inner parts like piston, port, valve etc., which defines the forces set up [soft / hard] are almost infinite. The objective of this paper is to measure, objectify and evaluate the performance of two such optimum setting in various ride and handling events. A passenger car set up with an optimum soft & hard suspension damping force is studied for various ride and handling sub-attributes and their conflicts are examined in detail from a performance point of view:

With strict upcoming regulation norms, it becomes a challenging task for automotive industry to develop highly efficient engine that meets all the regulation requirements. The focus of automakers is to utilize fuel energy in most efficient way and to reduce the energy loss from the engine to improve thermal efficiency. Heat loss to the cooling medium is one of the prime losses inside the combustion chamber. Thermal barrier coating is used to reduce heat losses across combustion chamber surfaces (Piston, head, valves and cylinder liner) as it provides good insulation because of the prominent properties of coating materials like low thermal conductivity, low heat capacity, high melting point etc. This paper presents application and impact of thermal swing coating on thermal efficiency. Thermal swing coating material follows gas temperature quickly throughout the cycle which reduces the temperature difference between gas and coating surface and thus reduces the heat loss.

Rapidly changing emission and fuel efficiency regulations are pushing the design optimization boundaries further in the Indian car market which is already a very cost conscious. Fuel economy can be improved by reducing moving parts friction and weight optimization. Driveline or Transmission power losses are major factor in overall efficiency of rotating parts in a vehicle. Transmission efficiency can be improved by using low viscosity oil, reducing oil quantity and reducing churning losses in car transmission. Changes like low viscosity and reduced oil volume give rise to challenges like compromised lubrication and durability of rotating parts. This further leads to extended design cycles for launching new cars with better transmission efficiency and fuel economy into the market. Design cycle time can be reduced by using CFD simulation for oil flow validation in the early design stage.

In the modern automobile scenario in developing countries, customers are getting more meticulous and market more competitive. Now even the budget vehicle customer expects desirable vehicle performance in specific use cases of the vehicle that were previously not focused by designers. Hence, the focus on perceived quality challenges automobile engineers to go the extra mile when it comes to the cost-effective design of parts that are tangible to the customer. A vehicle's cowl cover is one such exterior component. The primary functions of this part are to provide air intake opening for the HVAC system and cover the components like wiper motor. The aesthetic function is to cover the gaps between windshield, hood, and fender as seamlessly as possible. A specific role of cowl cover, which calls for a designer's attention, is its load-bearing capability.

As the automotive market is very dynamic and vehicle manufactures try to reduce the vehicle development cycle time, more focus is being given to CAE simulation technologies to reduce the design cycle time and number of physical tests. CAE engineers are continuously working on improving the accuracy of CAE simulation, such as using flexible body dynamic simulation in place of linear static analysis. Strength calculation under dynamic condition is more accurate as compared to static condition as it gives more clear understanding of stress variation with motion, contacts and mass inertia. Failure has been observed in new development of valve train pivot screw under test conditions. As per linear static analysis, design was judged OK. Normal linear static analysis is a two stage process. In first stage loads are calculated by hand or peak loads are taken from multibody dynamics (MBD) rigid body analysis.

Nowadays, Road Load Simulators are used by automobile companies to reproduce the accurate and multi axial stresses in test parts to simulate the real loading conditions. The road conditions are simulated in lab by measuring the customer usage data by sensors like Wheel Force transducers, accelerometers, displacement sensors and strain gauges on the vehicle body and suspension parts. The acquired data is simulated in lab condition by generating ‘drive file’ using the response of the above mentioned sensors. Due to non- linear nature of the vehicle parts, transmissibility of load is a complex phenomenon. Due to this complex transmissibility, good simulation at wheel center does not always ensure good correlation at all vehicle locations. The low level of correlation is common at the locations like engine mount, horn bracket and other overhanging brackets which are away from the wheel center.

IC Engine Timing belt is a major noise prone area and it takes time during development to achieve acceptable NVH characteristics. In an existing engine under series production noise problem observed due to excitation of timing belt span by crank timing sprocket tooth. From vehicle perspective noise was heard in vehicle cabin at around idling RPM and a second peak observed around twice the initial RPM. This paper includes a methodology for use of computer based analytical simulation methods to predict timing belt dynamic behavior and NVH characteristics. Along with development of computer based multi body dynamic model for timing belt, validation of simulation model with actual testing was done and after correlation of testing and simulated results countermeasure were finalized based on iterations in multi body simulation model.

The air pollution and global warming has become a major problem to the society. To counter this worldwide emission norms have become more stringent in recent times and shall continue to get further stringent in the next decade. From OEMs perspective with increased complexity, it has become a necessity to use simulation methods along with model based systems approach to deal with system level complexities and reduce model development time and cost to deal with the various regulatory requirements and customer needs. The simulation models must have good correlation with the actual test results and at the same time should be less complex, fast, and integrable with other vehicle function modelling. As the vehicle fuel economy is declared in cold start condition, the fuel economy simulation model of vehicle in cold start condition is required. The present paper describes a methodology to simulate the cold start fuel economy.

With more stringent emission norm coming in future, add more pressure on IC engine to improve fuel efficiency for survival in next few decades. In gasoline SI (spark ignition) engine, valve events have major influence on fuel economy, performance and exhaust emissions. Optimization of valve event demands for extensive simulation and testing to achieve balance between conflicting requirement of low end torque, maximum power output, part load fuel consumption and emission performance. Balance between these requirements will become more critical when designing low cost valve train without VVT (Variable valve timing) to reduce overall cost of engine. Higher CR (Compression ratio) is an important low cost measure to achieve higher thermal efficiency but creates issue of knocking thereby limiting low speed high load performance. The effective CR reduction by means of late intake valve closing (LIVC) is one way to achieve higher expansion ratio while keeping high geometric CR.