Study Of The Effect Of The Brake Disc On Temperature And Stress Fields Of The Brake Pad

The brake disc surface temperature and stress increased with the increase of the train speed,the thermal fatigue failure is the main reason of restricting the life of brake disc. In the process of braking,the structure of the brake pad directly affects the heat distribution of the surface heat of the brake disc,and the distribution of surface heat directly affects the service life of the brake disc.Therefore,study of the relationship between the distribution rule of temperature and thermal stress of the brake disc and the structure of the brake disc is the main method to improve the braking safety and the service life of the brake disc.In this paper, study on the effect of pad structure on the heat distribution on brake disc surface based on the characteristics of heat generation and heat dissipation of disc. At the same time, Non-linear FEM software ABAQUS is applied. Thermal- mechanical coupled model of pad and brake disc is established. According to real size of brake friction of high speed train, Train constant speed friction process is simulated, and the relationship of pad structure and temperature field as well as thermal stress of brake disc is analyzed, and principal conclusions are educed as followed:(1) Based on the relationship between the distribution characteristics of block brake and the temperature distribution of brake disc surface, investigated the characterization method of brake structure, defined the brake friction radius, the friction arc length and the friction area, this parameter can be characterized by the brake structure influence on the brake disc surface heat distribution, which has certain guiding significance for the structure design of brake.(2) The shape and arrangement form of brake block can affect the temperature field of the brake disc and the distribution of stress field. Simulation results show that the highest temperature of the brake disc surface and the maximum stress ring distribution matched with the brake disc friction radius in the theoretical calculation largest structure factor.(3) The brake disc surface temperature and the maximum stress increases with the brake structure factor. Numerical simulations verify the brake structure factor can characterize the structure of the brake disc and brake pads brake heat distribution,and can be distributed surface thermal characterization of brake disc stress.(4) Optimized of the brake structure composed of nine circular brake block by using the structure factor. Optimized dual brake decreased the highest temperature and the maximum thermal stress of disc surface,and improved uniformity degree of dual disc brake disc surface temperature along the radial distribution, in order to improve the service life of the brake disc.