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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 today’s Indian automotive industry, vehicles are becoming more complex and require more efforts to develop. Also, new and upcoming regulations demand more trials under varied driving conditions to ensuring robustness of emission control. Combined with expectations of customer to get new products more frequently, requires solutions and methods that can allow more trials with required accuracy to ensure compliance to stricter regulation and delivery a quality product. This translates into more trials in less time during the development life cycle. Recently, to overcome above challenge, there has been focus on simulating the vehicles trials in engine bench environment. ‘Road to Lab to Math’ (RLM) is a methodology to reduce the effort of On-road testing and replace it with laboratory testing and mathematical models. Also, on-road testing of prototype vehicles is expensive as it requires physical parts.

With the development of automobile industry, customer awareness about NVH (Noise, Vibration and Harshness) levels in passenger vehicles and demands for improving the riding comfort has increased. This has prompted automobile OEMs to address these parameters in design stage by investing resources in NVH research and development for all components. Better NVH of Radiator Fan Module (RFM) is one of the parameters which contributes to cabin comfort. The basic objective of RFM is to meet engine heat rejection requirements with optimized heat transfer and air flow while maintaining NVH within acceptable levels. The rotating fan (generally driven by an electric motor), if not balanced properly, can be a major source of vibration in the RFM. The vibration generated thus, can be felt by customer through the vehicle body.

In the present automobile market, customers have put demand for smaller cars with better ride and comfort. For small diesel engine cars, where the comfort is known to be inferior to its gasoline siblings, the effect of engine excitation and road inputs has posed the problem of seat back vibrations. Low frequency vibrations are observed at irregular road inputs, which directly get transferred to the human body through the seat back resulting in fatigue and discomfort. This paper describes the use of testing and CAE in reducing the seat back vibrations. First step of the study includes the frequency response functions (FRF) of the seat frame and road data. The CAE model is validated with the test data and the problem areas are identified. The countermeasure design modifications in the seat frame structure are analyzed using CAE (Normal Mode Analysis). The feasible countermeasure action is road tested and clearly shows a reduction in the vibration levels coming on the seat back.

With steep increase in fuel prices, there is a strong need for development of better engines with improved performance and emissions. This needs a dedicated effort on engine hardware optimization for lower CO2 levels. Exhaust muffler design is trade-off between noise, backpressure and size/weight. With increase in exhaust muffler volume and simplification of structure there is a corresponding drop observed in exhaust pressures. Study of such a phenomenon would give an insight to benefits achieved based on changes in muffler volumes/structure. This in a way leads to engine improvement. In this paper it has been shown how exhaust muffler characteristics (size and internal construction) impacts engine performance.

Vehicles which are sold and put into service in a country have to meet the regulations and standards of that country. Every country has a separate regulation and approval procedure which requires expensive design modifications, additional tests and duplicating approvals. Thus, there is the need to harmonize the different national technical requirements for vehicles and form a unique international regulation. With this rationale, the World Forum for Harmonization of Vehicle Regulations of the United Nations Economic Commission for Europe (UN/ECE/WP29) has brought governments and automobile manufacturers together to work on a new harmonized test cycle and procedure which is to be adopted around the world. This lead to the development of Worldwide Harmonized Light Duty Test Procedures (WLTP) and Cycles (WLTC). The test procedure is divided into 3 cycles, depending on a power to mass ratio of the tested vehicle.

Automobile Catalyst are used to convert Harmful gases emitted by vehicle (CO, HC, and NOx) to less Harmful gas (CO2, H2O and N2), Catalyst Loading comprises of Platinum, Palladium and Rhodium (Rare earth metals) metal powders combined in slurry and wash-coated onto a ceramic brick. Ever since the introduction of BS6 Emissions norm (stricter emission regulation), Catalyst loading content has increased in all vehicles. The Price of these rare earth metal are increasing day by day. Typically, a BS6 regulation catalyst contains a few grams of loading content. In some vehicles there are more than one catalyst (due to regulation requirement) and in some cases catalysts are also located in the underbody, in such cases, Number and location of catalyst makes the vehicle an easy target for thieves. Recently local police authorities around the country have captured many catalysts theft gangs.

Shorter product development cycles, densely packed engine compartments and intensified noise legislation has increased the need for accurate predictions of passenger cars Exhaust system noise at early design stages. The urgent focus on the increasing CO2 emissions and the efficiency of IC-engines as well as upcoming technologies might adversely affect the noise emission from an exhaust system, so it is becoming increasingly important to evaluate the sub system level noise emissions in an early design stage in order to predict and optimize the exhaust system performance. Engine performance and vehicle NVH characteristics are two important parameters on which the design of the exhaust system has major influence. The reduction of exhaust noise is a very important factor in controlling the exterior and interior noise levels of vehicles, particularly to reach future target values of the pass-by noise and sound engineering for the vehicle.

Due to intense peak summer temperatures and sunny summers in tropical countries like India etc., achieving the required thermal comfort of car occupants without compromising on fuel efficiency is becoming increasingly challenging. The major source of heat load on vehicle is Solar Load. Therefore, a study has been conducted to evaluate the heat load on vehicle cabin due to solar radiations and its impact on vehicle air-conditioning system performance with various combinations of door glasses and windscreen. The glasses used for this study are classified as green, dark green, dark gray, standard PVB (Polyvinyl Butyral) windscreen and PVB windscreen having infrared cut particles. For each glass, part level evaluation was done to find out the percentage transmittance of light of different wavelengths and heat flux through each glass.

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 [2]. For generation of proper drive file, not only good FRF but ensuring stability of inverse FRF is also essential. Stability of the inverse FRF depends upon the simulation channels used. In this paper experimental approach has been applied for the optimization of the simulation channels to be used for simulation of normal Indian passenger car on 4 corners, 6-Axis Road Load Simulator. Time domain tests were performed to identify potential simulation channels.

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.

Manual transmissions dominate the Indian market for their obvious benefit of low cost and higher mechanical efficiency resulting in higher fuel economy. Synchronizer system in manual transmission enables smoother and quieter gear shifting. Synchronizer ring is the key element which provides the necessary frictional torque to synchronize the speed of gear and sleeve for smooth shifting. During vehicle running, synchronizer rings are free to rattle inside the indexing clearance. High engine torsional excitation and low clutch dampening can result into increased fluctuation of the input shaft of transmission. High fluctuation or lower contact area of synchronizer ring can lead to damage on the index area. This damage may cause hard gear shifting and gear shift blockage in case of extreme damage.

India has gone through a lot of transformation over the last decade. Today it is the 6th largest and one of the fastest growing economies in the world. Rising income level, increased consumerism, rapid growth in urbanization and digitization have attributed to this change. Government focus on “Make in India” for promoting trade and investment in India have ensured that India emerge as one of the largest growing economies in the world. The automotive industry played a pivotal role in the manufacturing sector to boost economic activities in India. The passenger car market has increased 3 times over the last decade and it has led to increased mobility options for many people across India. However, this has put concerns on the country’s energy security and emission levels. According to IEA’s recent report on global CO2 emission, 32.31 Gt of CO2 emissions were from fuel combustion in 2016, out of which transport sector contributed ~25%.

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.

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.

In recent years, world-wide automotive manufacturers have been continuously working in the research of suitable technical solutions to meet upcoming stringent carbon dioxide (CO2) emission targets, as defined by international regulatory authorities. Many technologies have been already developed, or are currently under study, to meet legislated targets. In-line with above objective, the enhancement of turbulence intensity inside the combustion chamber has a significant importance which contributes to accelerating the burning rate, to increase the thermal efficiency and to reduce the cyclic variability [9]. Turbulence generation is mainly achieved during the intake stroke which is strictly affected by the intake port geometry, orientation and to certain extends by combustion chamber masking. Conservation of turbulence intensity till 700~720 crank angle (CA) is achieved by optimized shape of combustion chamber geometry and piston bowl shape.

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.

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.

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.

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.