中文摘要：

给出了列车穿越隧道时在隧道入口形成涡流场的数值模拟过程．控制方程为三维黏性、可压缩、等熵、非定常流的N-S（Navier—Stokes）方程，空间离散采用了中心有限体积法格式，时间采用预处理二阶精度多步后差分格式进行离散，对列车与隧道之间的相对移动采用移动网格技术处理．计算结果与国外的试验结果基本一致．研究结果表明，在整个涡流的形成过程中，可以将这个过程分为连续的4个阶段，即涡的形成、发展、传播及破坏阶段．研究结果还表明，涡受到列车头部形状的影响要比受到列车速度的影响要大；喷射流速度与列车速度有关系．

英文摘要：

A cell-centered finite volume method for numerical integration of N-S equations has been presented here for three-dimensional unsteady viscous compressible isentropic flow to simulate the formation of vortex produced by the train entering a tunnel. The numerical procedure is based on preconditioned second-order accurate backward difference in time, the relative motion between the train and tunnel treated with sliding mesh technique. The results of numerical simulation agree with that of foreign. The results show that the formation of the vortex constitutes four phases, the pre-vortex phase, the vortex development phase, the vortex convection phase and the vortex breakdown phase. The duration of each of these phases has its own features,and further more,the effect of the train nose geometry is greater than the train speed＇s on the vortex evolution, and the jet velocity is related to the train speed.