Analysis of vibration and noise of internal combustion engine considering gear impact.

Abstract

When the loading torque is small in the internal combustion engine and gear transmission, the gear tooth separation is caused by the fluctuating torque. One of the measures to reduce the gear impact noise is supplying the oil to the rattle part. In order to analyze the impact vibration behavior through the oil film, the numerical calculation using time integration technique is not easy task because the colliding stiffness and oil film damping are connected in series and the mass of the connecting point is zero. In this paper a new method to calculate the vibratory response of the dynamic system involving the gear backlash partially filled with oil film is offered and applied to vibration and noise radiation analysis of the internal combustion engine with a gear train system. The effect of the oil film in the backlash on the gear impact force is evaluated and moreover it is discussed the relationship between the gear backlash and engine noise changing with engine rotational speed.