不同运行方式对高速地铁气动效应的影响

Influence of different operation modes on the aerodynamic effect of high-speed subway

为了研究时速140km/h高速地铁列车以不同运行方式在隧道中运行时的气动效应,采用三维、可压、非定常N-S方程的数值计算方法,对地铁列车由明线驶入隧道及站间运行时产生的气动效应进行数值模拟,分析不同运行方式对高速地铁隧道气动效应的影响。研究结果表明:列车站间运行时,车体表面测点压力峰峰值沿车长方向基本不变;而列车由明线驶入隧道时,车体表面测点压力峰峰值从头车向尾车逐渐降低。2种运行方式下的隧道壁面测点压力峰峰值均在中间风井处达到最小值。并且列车由明线驶入隧道时的最大车体表面和隧道壁面压力峰峰值分别为列车站间运行时的1.37倍与1.49倍。不同列车密封指数下,列车由明线驶入隧道时的车内压力变化均大于列车站间运行时的车内压力变化。因此,地铁列车由明线驶入隧道时的空气动力学效应比站间运行时更加不利。

To research the aerodynamic effect of high-speed trains running with different operation modes in tunnel whose speed is 140 km/h, it simulated aerodynamic problems caused by trains when they enter tunnel from open air and run between stations based on the three-dimensional, compressible and unsteady N-S equation method. The influence of aerodynamic effect with different trains’ operation modes in high-speed subway tunnel was analyzed. The results show: The peak-to-peak value of measurement points on train’s surface is constant along the direction of train length by trains entering tunnel from open air. But the peak-to-peak value of measurement points on train’s surface decreases from head carriage to rear carriage by trains running between stations. The peak-to-peak value of measurement points on tunnel wall is the minimum at the place of middle shaft by trains running with different operating modes. And the maximal peak-to-peak value on train’s surface and tunnel wall caused by trains entering tunnel from open air is respectively 1.37 times and 1.49 times compared with trains running between stations. The pressure changes inside carriages caused by trains entering tunnel from open air is larger than that caused by trains running between stations with different tightness index. As a result, the aerodynamic effect caused by trains entering tunnel from open air is worse than the aerodynamic effect caused by trains running between stations.