防风栅对高速列车挡风作用的数值模拟

该文采用CFD数值模拟的方法研究了防风栅对高速列车的挡风作用。首先,根据附加源项法的基本原理,将防风栅等效为多孔介质,给出了对其挡风性能模拟的高效方法,通过与风洞试验对比,验证了该方法的有效性。在此基础上,研究了不同开孔率防风栅下游的流场特征,结果表明,40%开孔率的防风栅挡风性能较好。然后,应用动网格技术,仿真得到列车运行状态下的气动力,对比表明该文得到的列车气动力与实测结果相吻合。最后,通过脱轨系数和轮重减载率,评估了40%开孔率的防风栅遮挡下高速列车在横风作用下的安全性,结果表明,该种防风栅提高了列车在强风区的运行效率。

WINDBREAK PERFORMANCE OF WIND FENCE ON HIGH SPEED TRAIN BASED ON NUMERICAL SIMULATION

The windbreak performance of the wind fence on a high speed train is investigated by CFD numerical simulation method. Firstly, a wind fence is equivalent to porous media and the additional source method is explored to simulate its windbreak performance. By comparing of the results drawn from simulation and wind tunnel tests, the provided method is validated. Based on the given method, the windbreak performance of a wind fence with different porosity is investigated, the results show that optimal porosity is 40%. The aerodynamic forces of a train are simulated by the moving grid method, which agree with the results drawn from the site measurement. Finally, the safety of a high speed train is evaluated in the action of across wind. The results show that a wind fence can improve the efficiency of a train.