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Diesel engines as prime movers for passenger cars are becoming popular, primarily due to their superior thermal efficiency. However, the peak thermal efficiency does not exceed 35 to 40% even in the best engines. Huge efforts are being put in to improve engine efficiencies to meet ever stringent fuel economy requirements. Such efforts are mainly focused on combustion improvement and parasitic losses reduction. However, a large part of the energy input to engine is lost to cooling system, exhaust gases and other heat losses. Such losses are higher at part and low loads which is where the engine operates in normal usage conditions. This paper analyses in detail the various energy losses at different engine operating regimes. Quantification of losses and understanding of loss mechanism serves as a starting point for future technologies to recover the lost energy. Quantification of losses: Losses in different systems are quantified at different engine operating regimes.

To sustain market leadership position one has to continuously improve their product and services so that on one hand customer expectations are met and on the other hand business profitability is maintained. Value engineering is one of the approach through which we can achieve these two objectives simultaneously. Enhancing the value of running products is always a challenge as there is limited scope and flexibility to modify the current design and processes. Value engineering approach, integrated in product development cycle, brings great opportunity to upgrade the new and running products. This study reveals approach to upgrade the base engine of Maruti Alto. Upgraded engine is used in Alto 800 vehicle launched in October 2012. Improvement points were studied based on the business requirement, market competition, and legislative requirements. Based on functional improvement points, all the design parameters were studied and finalized.

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.

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.