时速600 km磁浮列车驶入隧道时初始压缩波特征的数值模拟

为分析高速磁浮列车驶入隧道时产生的初始压缩波特征, 采用三维可压缩非定常流动的N-S方程和SST κ-ω湍流模型, 基于重叠网格法和有限体积法, 以国内正在研发的时速600 km高速磁浮列车头型为研究对象, 建立了高速磁浮列车驶入隧道的计算模型, 通过分析距隧道进口端内不同距离横截面上不同测点的压力及压力变化率, 得到了车头驶入隧道洞口初始压缩波的空间分布特性和传播特性, 以及不同速度对初始压缩波波动幅值的影响。研究结果表明: 初始压缩波在列车驶入隧道前开始形成, 形成初期具有三维特性, 在隧道截面同一高度上, 靠近车体一侧的初始压缩波压力要比远离车体一侧大; 在隧道截面同一侧, 靠近车体一侧高度越低, 初始压缩波压力越大, 而远离车体一侧初始压缩波压力与高度无关; 当列车驶入隧道一定距离后, 在列车头部前方约36 m处隧道内同一断面处压力相同, 初始压缩波由三维波变成一维平面波; 在列车流线型头部驶入隧道约0.15 m时, 位于隧道300 m测点处的初始压缩波的压力变化率达到最大值; 列车速度越高, 初始压缩波压力峰值越大, 位于隧道100 m处测点的初始压缩波的压力峰值与列车速度的2.5次方近似成正比, 压力变化率峰值与速度的3次方近似成正比。 

Numerical simulation of initial compression wave characteristics of 600 km·h-1 maglev train entering tunnel

In order to analyze the characteristics of initial compression wave generated when a high-speed maglev train enters a tunnel, the three-dimensional compressible unsteady flow N-S equation and the SST κ-ω turbulent flow model were used. Based on the overlapping grid method and the finite volume method, taking the head shape of a high-speed maglev train with a speed of 600 km·h-1, which was developing in China as a research object, a calculation model of a high-speed maglev train entering a tunnel was established. By analyzing the pressure and pressure change rate at different measuring points on different cross sections from entrance of tunnel, the spatial distribution characteristics and propagation characteristics of initial compression wave when the train heads enter into the tunnel opening were obtained, and the effect of different speeds on the amplitude of initial compression wave fluctuation were also obtained.Research result shows that the initial compression wave starts to form before the train enters the tunnel. It has three-dimensional characteristics at the initial stage of formation. At the same height of the tunnel cross section, the pressure of initial compression wave on the side closer to the train body is greater than the pressure on the side farther from the train body. On the same side of the tunnel cross section, the lower the height near the train body, the higher the pressure of initial compression wave, but the pressure of initial compression wave on the side far from the train body is independent of the height. When the train enters the tunnel for a certain distance at the position about 36 m in front of the train head, the pressure at the same section in the tunnel is the same, and the initial compression wave changes from a three-dimensional wave to a one-dimensional plane wave. When the streamlined head of train enters the tunnel at about 0.15 m, the pressure change rate of initial compression wave at the 300 m measuring point at the tunnel reaches the maximum value. The higher the train speed, the greater the peak pressure of the initial compression wave. The peak pressure of initial compression wave at the 100 m measuring point at the tunnel is approximately proportional to the 2.5 th power of the train speed, and the peak pressure change rate is approximately proportional to the 3 rd power of the speed.