高速铁路挡风墙高度和距离优化分析

为探讨挡风墙对列车横向气动性能的影响，基于可压缩粘性流体Navier-Stokes方程和k-两方程湍流模型，采用有限体积法，计算了列车在直线和不同半径曲线线路上运行时，不同挡风墙高度和距离的275种工况下列车侧向力和侧翻力矩，获得了最佳挡风墙高度和距离.研究结果表明:在列车速度为200~400 km/h，风速为20~40 m/s的条件下，列车在直线线路上运行的最佳挡风墙高度和距离分别约为1.90和3.90 m；当弯道半径为1 000~7 000 m时，曲线线路最佳挡风墙高度随弯道半径增大线性减小，最佳挡风墙距离与弯道半径关系不大，约4.50 m；风速和列车速度对挡风墙的最佳高度和最优距离影响很小；如果挡风墙高度过低或距离过近，头车和尾车所受侧向力和侧翻力矩方向不同. 

Optimization Analysis of Height and Distance of Shelter Wind Wall for High-Speed Railway

Based on the Navier-Storkes equations of viscous compressible fluid and the k- two-equation turbulent model, side forces and rolling moments acting on a train were calculated by means of the finite volume method. The effects of shelter wind wall on transverse aerodynamic forces acting on trains were investigated numerically, and the optimal height and distance of shelter wind wall were obtained, including 275 cases of straight railway and curved railway with different radii under different wall heights and wall distances. The research results show that the optimal height and distance of shelter wind walls on a straight railway line are about 1.90 and 3.90 m respectively when train speed is 200 to 400 km/h and transverse wind speed 20 to 40 m/s. When a train runs on a curved railway line with a radius of 1 000 to 7 000 m, the optimal height decreases linearly with the increase of the radius, while the optimal distance is about 4.50 m with little relation to the radius. Wind speed and train speed have a few effects on the optimal wall height and distance. If wall height is too low or wall distance is too small, the direction of side forces and rolling moments acting on the head and rear cars are different.