地铁用制动电阻的弹性热力耦合仿真分析

Elastic Thermal-mechanical Coupling Simulation Analysis of Subway Brake Resistance

为分析地铁列车电制动过程中,制动电阻片表面温度场、位移场及应力场的分布,基于有限单元法,建立了三维热力耦合分析模型,并运用有限元软件进行了具体的求解计算,以回归得到了结构变形量与温度的关系曲线。在应力场的计算中引入了最小二乘法,从而以三次有限元计算求得温度场、位移场、应力场的耦合解,以改善计算精度。通过不同冷却条件下计算结果的比较,为制动电阻片采取合适的方法抑制变形提供了依据。

Three-dimensional model of thermal-mechanical coupling analysis was established based on FEM in order to analyze the distribution of surface temperature, displacement and stress field on the brake resistance chip in the process of subway's resistance brake. Special software was used to solve the FEM model. The regression curve was obtained to depict the relationship between structure distortion and temperature. The least square technique was introduced into stress field computation for more accurate solution. Therefore, the solution of coupled temperature, displacement and stress field was obtained by three processes of FEM computation. By comparison of solutions obtained under various cooling conditions, the theory ground was provided for adopting appropriate methods to restrain the deformation of the resistance chip.