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The problem of crankshaft torsional vibrations is inherent to the reciprocating internal combustion engines. Till date, in multi-cylinder internal combustion engines torsional vibrations which increases vibratory torque is the major reason for the failures of crankshaft due to raised fillet stresses. The torque applied to crankshaft is not constant in time, but it varies in a complex manner as a function of crankshaft position for each cylinder. The excitation that causes torsional vibrations of crankshaft is the Gas firing pulse phasing in the cylinders of an engine. The Crankshaft natural frequencies get excited several times through out the operating speed of engine by different components of firing pulse harmonics, called orders of an engine. The vibration amplitudes at these critical speeds are commonly high enough, so that the crankshaft as well as any accessory coupled to the crankshaft may fail.

Reducing the vibrations in the powertrain is one of the prime necessities in today's automobiles from NVH and strength perspectives. The necessity of 4×4 powertrain is increasing for better control on normal road and off-road vehicles. This leads to bulky powertrains. The vehicle speeds are increasing, that requires engines to run at higher speeds. Also to save on material costs and improve on fuel economy there is a need for optimizing the mass of the engine/vehicle. The reduced stiffness and higher speeds lead to increased noise and vibrations. One more challenge a powertrain design engineer has to face during design of its transmission housings is the bending / torsional mode vibrations of powertrain assembly. This aggravates other concerns such as shift lever vibrations, shift lever rattle, rise in in-cab noise, generation of boom noise at certain speeds, etc. Hence, reducing vibrations becomes an important and difficult aspect in design of an automobile.

Reducing the vibrations in the drivetrain is one of the prime necessities in today’s automobiles from NVH and strength perspectives. The virtual drivetrain simulation methodology to predict the driveline induced excitations transmitted to vehicle is developed for three cylinder engine using Adams View. The obtained mount forces from Adams dynamic simulation is correlated with the measured test data at vehicle level and the good correlation is observed. Paper discusses on the methodology of virtual drivetrain using Adams view and the correlation of measured dynamic mount forces with simulation results. This correlation gives the confidence that the developed simulation methodology can be used to get the mount forces of different orders from drivetrain.