市域列车隧道内站台越行气动特性分析

Analysis of aerodynamic characteristics of urban trains overtaking platform in tunnels

为提升市域列车隧道内越站时的运行安全性和旅客乘坐舒适性,文章采用紊流模型和三维非定常、可压缩、黏性纳维-斯托克斯方程,开展隧道内越行列车车外气动压力和车内压力波动的仿真分析与试验研究。研究结果表明:列车越站站台无车时的列车表面压力变化幅值、横向力和倾覆力矩大于站台有车工况,且随着测点后移其差值逐渐减小。列车越站站台有车时,越行车车内3 s压力变化幅值和1 s压力变化幅值都小于站台无车工况;站台有车时车内压力变化若要满足不大于800 Pa/3 s的要求,则列车所需动态气密指数至少为4 s;站台无车时车内压力变化若要满足不大于800 Pa/3 s的要求,则列车所需动态气密指数至少为5 s。

To enhance the operational safety and passenger comfort of urban trains overtaking station in tunnels,this paper adopts the turbulent flow model and three-dimensional unsteady compressible viscous Navier-Stokes equations to conduct simulation analysis and experimental research on the aerodynamic pressure fluctuations outside and the pressure fluctuation inside overtaking trains in tunnels.The research results indicate that when the train passes through the platform,the amplitude of surface pressure variation,lateral force and overturning moment on the train when there is no train on the platform are greater than when there is a train on the platform,and the difference gradually decreases as the measuring point moves backwards.When the train passes through the platform with a train on it,the amplitude of pressure variation for 3 s and 1 s inside the train is smaller compared to when there is no train on the platform.If the pressure change inside the train needs to meet the requirement of no more than 800 Pa/3 s when the platform has a train,the dynamic air tightness index required for the train is at least 4 s.If the pressure change inside the train needs to meet the requirement of no more than 800 Pa/3 s when the platform has no train,the dynamic air tightness index required for the train is at least 5 s.