高速列车在桥梁上行驶时空气动力特性的数值模拟研究

利用国际上通用的流体力学计算软件FLUENT作为研究工具,对高速列车在地面和桥梁两种行驶状态下的外部流场进行了数值模拟,分析桥梁的存在及其特征尺寸对列车气动力的重要影响。通过比较列车在不同高度、不同宽度及不同横截面形状桥梁上行驶时的气动力情况,得出针对本文选定的桥梁设计方案,桥梁的存在增大了列车倾覆危险性的结论;同时发现存在一个最危险桥梁宽度,此时列车尾部抬升和倾覆的危险最大,而当桥梁宽度增大到一定数值后,桥梁的存在将不影响列车受力;另外肯定了桥梁横截面形状接近流线型对改善列车受力有积极作用。

Numerical Simulation of the Aerodynamic Behaviors of a High-speed Train Traveling on the Bridge

The aerodynamic behaviors of a high - speed train traveling on the bridge are numerically investigated by using the software FLUENT in this dissertation. By comparing the aerodynamic forces when the train runs on the bridges of different height, width and cross section, author concludes that the bridge can enhance the fatalness of capsizing. Author also finds out there is a dangerous bridge width, which is the most possible to make the train capsize. But when it is wide enough, the bridge will have no influence on the aerodynamic forces. At last, author affirms that if the cross section of a bridge approaches streamline shape, the aerodynamic forces can be improved.