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In order to stand apart from the competition, there is an ever growing demand in Indian commercial vehicle segments to reach higher fuel economy while achieving the emission goals set by the BS-VI norms. With emissions standard set by BS-VI, novel techniques to improve fuel efficiency have to be considered that have least impact with respect to NOx and soot emissions. The optimization of exhaust and intake valve lifts with respect to engine speed, technology commonly known as Variable Valve Lift and Timing (VVT/VVL), has been implemented in many passenger vehicles propelled by gasoline engine. The aim of this work is do initial assessment of utilizing the VVL method on a LMD commercial vehicle diesel engine. A 3.8 litre BS-VI turbocharged EGR engine is used for this study. Valve lift and timing optimization for better fuel efficiency at rated power engine speed is carried out by using one-dimensional thermodynamic simulation software AVL BOOST.

In cylinder combustion and emission characteristics are dependent on piston bowl geometry design. In-cylinder fuel air mixing and flame front movement are influenced by piston bowl shape and design. These phenomena in turns affect the combustion behavior and the power developed by the diesel engine. In this study piston bowl geometry optimization of a LMD diesel engine is carried out to improve the torque and BSFC output at low end rated operating zones. The optimized bowl geometry is also incorporated in the engine and validated on the test bed. In this work, a commercially available CFD code AVL FIRE is used for combustion simulation and bowl geometry optimization. The validation of in-cylinder combustion simulation of a 2 liter Turbocharged LMD BS-VI diesel engine with base piston bowl geometry is carried out with the available test data.

This work is an effort to find the parallelism between the volumetric efficiency of a Gerotor, and its inherent design parameters: number of teeth, tooth profile, outer dimensions of diameter and thickness, and the input power (torque and speed). The preliminary relations are derived from the software simulation of a range of Gerotor models with varying aforementioned parameters. These results are augmented by a previously proposed method of theoretically estimating the displacement of a Gerotor. Then, these results are validated and revised by practical results from three different Gerotors with epitrochoidal and its conjugate profiles, which are used in automotive applications like engines and transmissions. These relations can be used for choosing parameters yielding the maximum efficiency in specific environments: the packaging space, the input available, and the output required.