Dynamic analysis of effect of progressive crack and variation in center distance on vibration of spur gears

Abstract

Gears are very important components of every mechanical system. The loading pattern in case of spur gears in mesh is highly dynamic in nature and has impact on vibrations. Excessive vibration hampers the performance of the machine. The presence of cracks on gears and change in center distance directly influences the mesh stiffness. This paper endeavors to investigate the effect of progressive cracks which are developed with passage of time. This is done by developing an improved dynamic model for different intensity of cracks considering misalignment of root circle and base circle. The improved model also takes into consideration the effect of change in center distance along with severity of crack. A MATLAB code is developed to solve the analytical equations to determine time varying mesh stiffness (TVMS) graphically. Through this study, it is established that TVMS is a good indicator for investigating the progression of crack on the gears and also change in center distance.