挟雨风对高速列车气动特性及运行稳定性影响的数值模拟

基于欧拉双流体模型，运用商用CFD软件FLUENT，对挟雨风条件下高速列车的气动特性和运行稳定性进行了三维模拟研究。分析了不同横摆角和暴雨强度下气动力和倾覆力矩的变化特征，并与无降雨条件下的相应结果进行比较。结果表明：受降雨影响，列车受到的阻力、侧向力和倾覆力矩均增大，列车气动性能损耗增加，运行稳定性降低。在模拟的降雨强度和横摆角条件下，阻力系数将提高1.8%~38.6%，侧向力系数提高0.1%~9.16%，导致列车的能耗增加；倾覆力矩系数提高1.8%~10.0%，意味着与净侧风相比，挟雨风进一步降低了列车的运行稳定性。

Numerical Simulating Effects of Rain-loaded Wind on the Aerodynamic Characteristics and Running Stability of High-speed Trains

Effects of rain-loaded wind on the aerodynamic characteristics and running stability of a high-speed train were studied by numerical experiments in three dimensions using commercial CFD software (FLUENT). The variation in aerodynamic forces and rolling moment of the high-speed train were detected at different yaw angles with/without rain intensities. The results show that the rainfall increases the drag force, side force and rolling moment of the train, which makes its performance worse and running stability degraded. Under the conditions of simulated rain intensities and yaws, the coefficients of drag force increased by 1.8%-38.6% and 0.1%-9.16%, respectively, meaning a rise of power energy consumption of the train. The coefficient of rolling moment has a rise of 1.8%-10.0%, indicating a decrease of running stability of the train, if compared with that under only-cross-wind condition.