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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.

Proper suitability of bolt preload is a pre-requisite whenever we go for component design change. In this paper we have considered connecting rod bolt for our analysis, where-in the design pre-requisite was whether same tightening specification could be carried forward from normal to fracture split type. The present work focuses on comparison of bolt design parameters, inertia force, contact pressure & bearing pressure calculation. Bolt safety factor was used as a parameter to check for the preload suitability with respect to engine max permissible speed. A systematic approach, considering guidelines from available bolt standard and literature was used for carrying out related analysis. For improving the quality of judgment, FEA tools along with durability testing was carried out at ARAI. In addition to this for better bolt preload control “Angle tightening method” of required specification was proposed, with results validated through physical testing.

In crank- train system, the prime objective of crankshaft is to facilitate the transformation of reciprocating motion of connecting rod into rotational motion at flywheel end. Moreover, the contribution of mass from crankshaft is in the same order as of flywheel assembly mass which accounts to approximately 40% to 50% of total mass of engine. Therefore, to accomplish the development of an efficient engine it is vital to optimize the crankshaft based on simulation parameters like balance rate, mass, torsional frequency, web shear stress etc. In the given work, crankshaft has been designed and developed for an engine used in light duty commercial vehicle. The defined work demonstrates the application of 1D simulation tool AVL Excite in development phase of the engine. To establish equilibrium between the weight and simulation guidelines, many iterations of models were evaluated and finally we were able to achieve mass reduction of nearly 8% from the base model.