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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.

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.

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.

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.

The automotive industry is gearing up to meet the accelerated emission compliance changes posed by the government. This transition to eco-friendly system would also necessitate an automotive engineer to retain the engine packaging as compact and simple as possible. The packaging layout considered should not be at the expense of deteriorating engine performance. The work started with concept level layout development, with the aim of having simplified system with minimum number of components. The engine on which the work was carried out was 4cylinder 3Liter with OHC configuration A number of layouts were developed which included gear type, belt drive and integrated shaft arrangement for driving FIP. Each of these concepts were brainstormed with its advantages and disadvantages, based on which two concepts were initially proposed for driving FIP system (i) Front Driven FIP (ii) Rear Driven FIP.

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.