Early Wear Fault Dynamics Analysis Method of Gear Coupled Rotor System Based on Dynamic Fractal Backlash

Abstract

The aim of this paper is to establish a typical gear coupled rotor system model and give an analysis of the early wear of the tooth surface. The tooth surface wear will cause the change of the backlash. Different from previous studies on the backlash, the backlash in this paper is a dynamic fractal backlash, which is obtained based on the fractal wear model of tooth surfaces. Firstly, based on the FA (Flodin and Andersson) model and our previous studies on the contact analysis of rough surfaces, a fractal wear model of tooth surfaces is established. Then, the system vibration response of embedded dynamic fractal backlash is compared with that of embedded fixed backlash. The results show that the traditional fixed backlash cannot reflect the small changes of the system response, while the dynamic fractal backlash can sensitively reflect changes of dynamic characteristics of the system, so this kind of mathematical model considering dynamic fractal wear will be more conducive to the analysis and prediction of gear wear faults in engineering.