عنوان مقاله [English]
One of the main factors influencing the fatigue of the components is the torsional vibration of the transmission system. These vibrations are mainly caused by periodic changes in the gas pressure inside the cylinder and the inertial forces due to the reciprocating motion of the crank and slider mechanism. Furthermore, in order to decrease fuel consumption, the new engines have been downsized. Consequently, due to the fewer number of power strokes, the vibration has increased. One way to reduce these vibrations is to use a dual mass flywheel (DMF). In this research, inertia torque and gas pressure torque of a three-cylinder engine are obtained. Then the equations of torsional vibrations in the time domain are solved. It is shown that angular velocity fluctuations in the secondary mass is reduced. Also, according to the torsional vibration model of two degrees of freedom, frequency responses under sinusoidal excitation are calculated. The results show that in the case of using DMF, the resonance is kept away from the working range of the engine. Finally, A parametric study is performed on design parameters and the effects of varying design parameters on oscillation amplitude of the angular velocity of the secondary mass are analyzed.