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The Indian automotive industry today stands as the most vibrant, modern and upbeat automobile market in the world and is the current focus of venture for almost every leading vehicle manufacturer in the world. New variants launched in Indian market are tested by instrumenting it with different sensors and running it on proving ground and public roads and further validated in the laboratory. These testing practices may be derived from the market needs and driving pattern of that region and trying to adopt for Indian condition. The driving characteristics obtained from other markets may not represent Indian driving patterns. Similarly Indian vehicle manufacturer also need to know updated driving characteristics, which is very much dynamic and changing with new type of roads/driving habit etc. There is a need to tune the vehicle for realistic Indian conditions and driving pattern.

Due to the well-known fact of higher thermal efficiency, diesel engines are more popular than any other fuelled prime movers. Because of this feature, the diesel engines are extensively used in almost all on road and off road applications. Power generation is another widespread application of the diesel engines. Over recent past years, stringent emission legislations have been imposed on reduction of emission parameters emitting from diesel engines. Central Pollution Control Board (CPCB) of India has proposed further reduction in emissions applicable from 2013, which are the most stringent limits in the world for this category of engines up to 75 kW. This paper deals with the strategies applied and experimentation details to meet the proposed CPCB Stage-II emission limits. The criticality increases exponentially for naturally aspirated versions. The experimental investigations are carried out on various capacities of 1.0 l to 3.25 l naturally aspirated diesel genset engines.

This paper is focused on the prediction of in-cylinder pressure, temperatures and engine-out NOx. One of the important factors influencing engine output parameters is the rate of heat release, which affects the in-cylinder pressure, temperature and engine out emissions. A single-zone model is formulated for prediction of heat release and in-cylinder pressure. Being a predictive model, this model does not required cylinder pressure as an input. Combustion pressure is predicted by modeling compression pressure, ignition delay, heat release, and heat loss. Required Sub-models have been obtained from the literatures. Fuel burning rate is predicted using Watson model. To retain the computational efficiency and better prediction accuracy a two-zone model has been formulated to predict NOx emissions. Flame temperatures are predicted by enthalpy balance. Thermal NO concentration is predicted by using basic Zeldovich mechanism.

Automotive Industry Standard (AIS)-031 specifies the requirement of strength of large passenger vehicles in case of rollover. In India the certificate is granted after the successful completion of rollover test of the vehicle as per AIS-031. Complete vehicle is used for rollover test in which the vehicle is tilted laterally in the ditch of 800 mm. Such tests with complete vehicle are costly and unaffordable to small bus body builders. So according to Annex 2 of AIS-031, manufacture can carryout rollover on body sections of the vehicle. This is an equivalent approval method which is less costly compared to rollover test on complete vehicle. It requires detailed study of superstructure and selection of weakest body sections from the given superstructure of bus, which in turn requires mass and energy calculation of body section. For doing rollover analysis using body section, bus is selected which has already passed a full-rollover test.

India already has the highest concentration of megacities and urban growth continues. Together with an increasing need for individual mobility in particular, the Indian market demands new vehicle concepts. German lower-Saxony research centre of Automotive Engineering (NFF) and The Automotive Research Association of India (ARAI) together with representatives from the automotive industry develop a research roadmap to satisfy the future demand for metropolitan cars.

The demands for safe, reliable, lighter, energy efficient and competitively priced products put a new emphasis on predictability of rolling bearing performance. This has prompted designers and engineers to estimate bearing life and optimize the design by taking into account different market requirement. Estimation of actual dynamic bearing load and life for specified class of vehicle depends upon various factors such as usage pattern, vehicle Gross Vehicel Weight (GVW), type of roads, speed, driving pattern, geographical area, ambient temperature, acceleration etc. For estimation and prediction of life of the particular wheel bearing type it is required to identify and measure customer usage loads for different targeted markets. The measurement maps all the affecting parameters to arrive at a generalized duty cycle for bearings. A software tool is developed to predict the bearing life with these measured inputs and this enables designers to optimize bearing designs for target markets.

Fatigue design has to account for the scatter of component geometry, material behavior and loading. Scatter of the first two variables is mainly due to manufacturing and material sourcing. Loading on the other hand depends decisively on operating conditions and customer usage. Loading is certainly most difficult to determine. Tests on proving ground or even long-term real time measurements are used to obtain actual load time histories. Because of the costs of measurements and safety measure, real-time measurements are used exceptionally to gain changes in the usage profile. In this paper, an attempt has been made to find the difference in the extrapolated data to the actual data. A comparison has been made between the actual road distance of 2000 km to the extrapolated data of 100 km, 500 km and 1000 km to 2000 km. The front Axle channel is taken for the study.

The physical and chemical properties of biogas affect the choice of technology used for biogas scrubbing and combustion; therefore, knowledge of these properties is useful for optimizing biogas utilization. Since biogas contains primarily as bulk components methane and carbon dioxide. Other trace components (nitrogen, hydrogen sulfide, and trace organics) are present in relatively small quantity, the magnitude of which varies greatly and depends on the composition of the material digested. Although the small concentration of these traced gases have little effect on the physical properties of the gas, which influence the choice of technologies. In the present work, the analysis of the biogas composition related to its effects on the physical properties of the gas and which influence the choice of technologies used for spark ignition engines is presented.

Electronics is widely used for improving the vehicle safety due to its characteristics like fast response, multi sensor interface and implementation of complex control strategy. Already a majority of vehicles are fitted with some kind of Electronic Stability Program (ESP) system in many countries to improve safety performance. Yaw stability is one of the major elements under ESP system. A project was undertaken to develop Yaw Stability Control (YSC) strategy. YSC strategy development is very challenging due to several issues like dynamics of event, ability of brake hydraulics and /or Engine torque controller to respond, proving of the strategy under different user scenarios etc. This paper describes the challenges faced and solutions tried out while development. The paper presents the YSC controller strategy, different regulatory requirements, test data and results with and without YSC on a typical SUV vehicle. The controller has been developed using Matlab Simulink environment.

In recent years the Government of India has supported the use of Liquified Petrolium Gas (LPG) in public and private vehicles. One of the ways to reduce emission is use of alternative fuels. Among alternative fuels, LPG is one of the most promising mainly because of its low exhaust emissions. The papers about LPG used in three wheeler, cars for SI or CI converted to SI engines had been published extensively in the last two decades. The applications of LPG to bi-fuel or single fuel engines are tried widely at this time. But the extensive study of LPG for small SI single cylinder two stroke engine of three wheeler two stroke engine is not reported in depth. This paper describes development of bi-fuel (LPG/Gasoline) concept of a single air cooled 200 CC single cylinder two stroke engine for three wheeler application.

Traction Control System (TRCS) has become a standard feature for most of the vehicles due to safety considerations. The system provides better drivability and acceleration performance on low friction surfaces. The TRCS typically tries to maintain slip value to an optimum value to maximize traction force by modifying engine torque and/or brake force intervention. However the optimum slip value is not a constant value and varies depending upon the road surface and tyre conditions. It is challenging task to predict this value dynamically and adapt TRCS under all driving situation. This paper presents an adaptive traction control system which tries to operate at optimum slip point irrespective of prior knowledge of road condition. The system continuously monitors vehicle dynamics parameters and corrects itself to maximize available traction. The controller has been developed using Matlab Simulink platform.

Biogas is one of the most promising alternatives fuel for the future. Biogas, when used in automotive field, will help to bring down harmful emissions. However, some technical improvements are still needed, especially in the Indian automotive sector. In this research work 100% biogas operated two wheeler four stroke SI engine has been tested for exhaust gas emissions. The result shows the lower emissions than the existing petrol engine limits without exhaust gas after treatment. The current work clearly indicates the breakdown of compression ratio barrier and it is shown that the engine runs smoothly at compression ratio of 11:1 without any tendency of auto-ignition. Experiments were conducted by varying compression ratios from 9:1 to 11:1 and retaining the combustion chamber design. This study shows that using biogas in SI engines, it is particularly beneficial to reach interesting conversion efficiencies with low emissions.