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The lubrication system of an internal combustion engine is a crucial component that performs a variety of functions, including lowering friction, cooling, supporting the load, and cleaning debris from the engine’s various moving components. Oil aeration refers to the phenomenon of trapping air bubbles in lubricating oil. High oil aeration can have a detrimental effect on engine performance since modern engines are equipped with parts such as VVT, HLA, RFF, PCJ, LCJ, and other components; whose operation is substantially impacted by the amount of air in circulating oil. In this study, an Inline 4-cylinder NA DOHC gasoline engine was tested with a densimeter-type aeration measuring machine. Test equipment layout which consists of hoses of various diameters and lengths were designed, fabricated, and instrumented to operate under different test conditions. Visual observations and quantitative measurements of oil aeration were performed in the oil sump.

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.

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.

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.

The biggest challenge in vehicle BIW design today is to make a light, cost effective and energy absorbing structure. With the increasing competition as well as increasing customer awareness, today’s vehicle has to satisfy several aesthetic and functional requirements besides the mandatory regulatory requirements. Working on global platform is challenging in order to comply with both pedestrian protection and low speed bumper impact (ECE-R42) and, at the same time, to meet the styling intent of reducing the front overhang. Pedestrian lower leg compliance demands space between bumper member and bumper: a condition that reduces the space available for energy absorption during low speed impact (ECE-R42). Therefore, reduction in front overhang poses a problem in meeting both the requirements with limited space. This paper outlines vehicle case study in order to optimize the design of Bumper Beam structure, for complying with regulatory requirements while satisfying the styling intent.

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.

Automobile components are usually subjected to complex varying loads. Thus, fatigue failure is a common mode of failure in automobile components. Accurately predicting the fatigue life is the key point for light weight and also reliability design of automobile components. Various life prediction theories are being used in the automotive industry for damage analysis using material S-N curves. However, due to variability in manufacturing, material spec etc. it is difficult to predict the experimental lives using conventional theories. Probability based statistical modeling is prevalent in the industry for life prediction. Probabilistic plots of cycles to failure to constant amplitude loads are plotted and used for prediction purpose. As the component is subjected to varying loads in real world, defining a single parameter i.e. damage would be more relevant compared to loads.

With the advent of stricter regulation for tail pipe emission and urge to reduce the carbon foot prints, the engine hardware has undergone through evolutionary changes over the years i.e., boosting, low viscosity engine oil, high pressure fuel injection, cooled EGR, friction reduction, downsizing etc. These technological changes have led to the challenge of increase in radiated noise level from the engine (source) due to increased number of auxiliary drives on engine i.e., Turbo charger, HP fuel pump along with faster combustion & harsher operating conditions. The fuel system is one such system which has become most intricate with operating pressure going above 2000bar in the fuel rail and capability of up to 10 fuel injection per combustion. These changes in hardware could result in abnormal noise generation during specific operating conditions which may result in customer annoyance inside vehicle cabin.

The biggest challenge in vehicle BIW design today is to make a light, cost effective and energy absorbing structure. With the increasing competition as well as increasing customer awareness, today’s vehicle has to satisfy several aesthetic and functional requirements besides the mandatory regulatory requirements. While working on global platform, it is challenging to comply with both pedestrian protection and low speed bumper impact (ECE-R42) and at the same time meeting the styling intent of reducing the front overhang. Pedestrian lower leg compliance demands space between bumper member and bumper, a condition that reduces the space available for energy absorption during low speed impact (ECE-R42). Therefore, reduction in front overhang poses a problem in meeting both the requirements with limited space. This paper outlines vehicle case study in order to optimize the design of Bumper Beam structure, for complying with regulatory requirements while satisfying the styling intent.

Hardened steel is the majorly used raw material for automotive components. In spite of its abundance, its application is limited due to low fatigue life in dynamic loading. Shot peening is one of the identified processes to improve the fatigue life of the ductile steel by inducing the work hardening & surface improvement. The process of shot peening involves the bombardment of shots on the component surface. As the process & technique, the shot size selection plays very important role in the fatigue life improvement as it alters the results substantially. Also during the process, shot size decreases due to the normal wear of the shots after hitting the component surface. As a result, there is always a ratio of various sizes of the shots involved in the process. Therefore it becomes imperative to control the shot size ratio for obtaining the required work hardening & possible fatigue life improvement.

Gearbox power transfer efficiency is a major factor in overall powertrain efficiency of a passenger vehicle. With rapidly changing emission and fuel efficiency regulations, there is a push to increase the gearbox efficiency to improve the overall fuel economy of the vehicle. In case of an existing gearbox, efficiency can be improved by using the low viscosity lubrication oil. Despite a benefit in increasing the gearbox efficiency, lowering down the viscosity of lubrication oil gives rise to few challenges with respect to its performance. One of these challenges is breather performance which defines that transmission oil should not come out of breather pipe in some pre-defined conditions during gearbox operation. As this validation is being carried out on proto parts when the complete system is ready, failure to satisfy the defined criteria for breather performance can lead to multiple trials.