The Thermal-structure Coupling Analysis Of Drum Brake On Different Braking Conditions

The drum brake is an important part of automobile braking system, and it is widely used in large or medium-sized buses and trucks because of its simple structure, large braking torque and low manufacturing cost. In the real life, drum brake often works in the extreme environment, such as high temperature and stress, especially when the automobile braking for a long time, the brake often appear hot recession phenomenon. Therefore, in order to improve the driving security and protect people’s lives and properties, it is very necessary to analyze the working process of the automobile brake comprehensively.First, this paper introduce the calculate method of the thermal boundary conditons and promote pressure when the thermal-structure coupling. Second, under the emergency braking condition, this paper makes an braking test and the finite element simulation based on the drum brake of Wu Ling Hong Guang passenger car, and then comparing to the two results to verify the accuracy of the finite element modeling method and thermal-structure coupling simulation process. Based on the same modeling method and thermal-structure coupling simulation process, this paper selects a heavy-duty truck’s drum brake as the research object, then using ABAQUS software to establish the simplified thermal-structure coupling finite element model of the drum brake, and simulate the working course under emergency braking condition, continuous braking condition and cycle braking condition.Based on the analysis of simulation results, we can obtain the distribution of temperature field, stress field, strain and the contact pressure, the results show that when the emergency braking process is finished, the temperature of brake drum presents a downward trend after the first rise. During the whole change process, the temperature of brake drum isn’t smooth and shows obvious “sawtooth” wavy. Under the continuous braking condition, the temperature of brake drum has been on the rise. Furthermore, the circumferential stress, axial stress and radial stress of the brake drum is very large, and they distributed unevenly. Under the cycle braking condition, the temperature and the thermal stress of brake drum is very high because of the accumulation of frictional heat, as a result, the braking performance of drum brake fell sharply and brake failure phenomenon can occur easily.