机车制动盘三维瞬态温度场与应力场仿真

基于三维循环对称有限元模型,提出了机车制动盘制动过程中温度场和应力场的计算方法。讨论了边界条件和各种相关参数的确定方法,尤其是机车整个制动过程中制动盘换热系数的计算方法。同时运用有限元软件ANSYS7进行了制动盘及相关部件三维瞬态温度场和应力场的仿真与分析。仿真结果表明:在制动开始阶段,制动盘迅速升温,高温区集中在制动盘摩擦面表层,最高温度达220℃;制动过程结束后,整个制动盘有一段较长时间的降温过程;制动盘系统各部分的最大热应力-时间曲线变化规律不一致,但均满足材料强度要求。仿真结果与实验数据相符,证明了该三维有限元模型及其温度场计算方法的正确性。

3-D Transient Temperature Field and Stress Field Simulation of Brake Discs

The calculation method of transient temperature field and stress field of a new type brake disc is put forward on the basis of 3dimentional cycle-symmetric finite element model.The boundary conditions and correlative parameters of brake discs are discussed,especially the coefficients of heat transfer during a whole brake process.The simulation and analysis of 3-D transient temperature field and stress field of brake discs and their accessories are given by applying finite element software ANSYS7.Simulation results show the following: At the beginning of the brake process,the temperature of brake discs rise rapidly;the high temperature section concentrates in surface friction layers of brake discs,and the top temperature is 220 ℃;there is a long temperature reduction process after the brake process;the trends of the change between maximun heat stress and time curve are different in different parts of brake discs,which,however,satisfy the strength requirement of the material. The simulation results are consistent with the experiment data,which verifies the validity of the 3-dimentional finite element model and its calculation method of temperature field.