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Infotainment has always been an important aspect of life which has made its way to car design. The cars today are much more advanced compared to their predecessors. The in-vehicle Infotainment advancements have followed the consumer electronics market in terms of technologies such as Touchscreen; App based Navigation, Voice Assistant and other multimedia services. This trend is going to expand further as smartphones have revolutionized the Infotainment domain with awareness and accessibility to customers. The Infotainment system in the cars are expected to be connected not only to the cloud but various vehicle controllers to display host of information & controls at customer`s fingertips. To design a system that supports connectivity to both cloud and vehicle is challenging in terms of cost and design for the OEMs. With focus on Indian market condition and global trends, this paper analyzes the customer expectation for Connected Infotainment system.

Gear noise and vibration in automobile transmissions is a phenomenon of great concern. Noise generated at the gearbox, due to gear meshing, also known as gear whine, gets transferred from the engine cabin to the passenger cabin via various transfer paths and is perceived as air borne noise to the passengers in the vehicle. This noise due to its tonal nature can be very uncomfortable to the passengers. Optimizing micro-geometry of a gear pair can help in improving the stress distribution on tooth flank and reducing the sound level of the tonal noise generated during the running of the gearbox when that gear pair is engaged. This technical paper contains the study of variation in noise level in passenger cabin and contact on tooth flank with change in micro-geometry parameters (involute slope and lead slope) of a particular gear pair. Further scope of study has been discussed at the end of the paper.

During vehicle development, numerous test are done to ensure safety & durability of the vehicle. One such test prescribed by regulation (IS 12009:1995) is side door intrusion test (SDIT). This test evaluates strength requirement of a side door of passenger cars to minimize the safety hazards caused by intrusion into passenger compartment in a side impact accident viz., initial, intermediate and peak crush resistance. In current scenario the passenger car manufacturers are striving hard on cost reduction by reducing the development cost. Thus, to predict the exact vehicle performance before its prototype stage is vital. This can be achieved by evaluating performance by the help of Computer aided engineering (CAE) During the SDIT, the load is applied to the outer surface of the door in an inward direction. This inward force applied by loading device is resisted by the door assembly, while door is pivoted at door latch and hinge.

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.

Shielding vehicle underbody or engine room components from exhaust heat is becoming a difficult task with increasing packaging constraints, which lead to the proximity of components with high temperatures of the exhaust systems. Heat insulators are provided to protect various components from exhaust system parts. Generally the requirement of heat insulators are fixed on the basis of benchmarked temperatures measured on vehicles with similar layout, during the initial phase of vehicle design. Also various CFD techniques are available to predict the surface temperatures on components in order to determine the necessity of a heat insulator. The aforementioned techniques use radiation and convection heat transfer effects on a complete vehicle model and the overall process generally takes considerable time to provide the results. This paper deals with a theoretical approach to predict the temperatures on nearby components due to exhaust system heat.

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 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.

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.

Exhaust system of an automobile is primarily employed in automobile to purify exhaust gases and reduce noise due to combustion. However, a side-effect of the above function is the increase in backpressure. As specified in various literatures, an increase in backpressure can lead to a deterioration on engine performance (Power & torque). Benefit of backpressure reduction can be further taken in terms improving the power & torque of engine or improving the fuel economy. With growing concerns related to global warming and CO2 emissions, reducing exhaust back pressure is one of the promising areas in engine design in order to improve the fuel economy of the automobile and achieving carbon neutrality targets. However, reducing the back pressure generally tends to deteriorate the noise attenuation performance of the Exhaust system.

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.

Blending locally produced ethanol with petrol will help India strengthen its energy security. India is making steady progress in raising the share of ethanol having increased to 8.1% in ethanol supply year 2020-21 (Dec-Nov) with target to achieve 10% ethanol blending in the ethanol supply year 2021-22. In future, Government of India is planning to start supply of 20% ethanol blended petrol from Apr’23 and to cover PAN India by Apr’25. Pure ethanol has lower calorific value than Petrol thus ethanol blended petrol will always have calorific value lower than that of petrol thereby deteriorating Fuel economy. On the other hand, ethanol blended petrol will have higher RON compared to petrol. Higher RON reduces knocking tendency thereby providing calibration optimization potential to optimize Spark timing. Optimized spark timing can help in improving Full Load Torque by reducing Phasing losses and operating closer to MBT.

Aerodynamic evaluation plays an important role in the new vehicle development process to meet the ever increasing demand of Fuel Economy (FE), superior aero acoustics and thermal performance. Computational Fluid Dynamics (CFD) is extensively used to evaluate the performance of the vehicle at early design stage to overcome cost of proto-parts, late design changes and for time line adherence. CFD is extensively used to optimize the vehicle’s shape, profiles and design features starting from the concept stage to improve the vehicle’s aerodynamic performance. Since the shape of the vehicle determines the flow behavior around it, the performance is different for hatchback, notchback and SUV type of vehicles. In a hatchback vehicle, the roof line is abruptly truncated at the end, which causes flow separation and increase in drag.

Recent automotive trend shows that customer demand is moving towards bigger size vehicle with more comfort, space, safety, feature and technology. Global market of SUV is projected to surpass 21 million units by 2020. Despite economic slowdown and weak new car sales worldwide, India and China will continue to be primary market for SUV due to sheer size of population, urban expanding middle class and larger untapped rural market. However, stricter emission norms push for clean and green technology and unfavorable policy towards use of diesel vehicle has made the SUV design very challenging due to conflicting needs. Due to bigger size of vehicle, aerodynamic design plays an important role in achieving emission targets and higher fuel efficiency. This paper highlights the aerodynamic development of Maruti Suzuki Vitara Brezza, which is an entry level SUV vehicle with high ground clearance of 198 mm and best in class fuel economy of 24.3 kmpl.