高速列车穿越有竖井隧道流场的数值模拟

为了降低噪声的影响，对高速列车穿越带有竖井的隧道时产生的压缩波进行了三维粘性流场数值模拟．控制方程采用三维粘性、可压缩、等熵、非定常流的Navier Stokes方程，空间离散采用中心有限体积法格式，时间离散采用预处理二阶精度多步后差分格式，对隧道壁采用壁面函数处理．计算结果与国外的试验结果基本一致．研究表明，竖井能降低隧道内的空气压力，其位置和断面大小对压力的变化有重要影响．

Numerical Simulation of Unsteady Three-Dimensional Flow Induced by High-Speed Train Entering Tunnel with Shaft

To decrease the effect of compression wave, the numerical simulation of a three-dimensional viscous flow induced by a high-speed train entering tunnels with a shaft was made. In the simulation, the Navier-Stokes equations, describing three-dimensional viscous, compressible, isentropic and nonstationary flows, were taken as the control equations, the cell-centered finite volume scheme for numerical integration of the Navier-Stokes equations was used for space discretization, and the preconditioned second-order accurate backward difference was adopted in time discretization. In addition, the walls and floor of a tunnel were described with wall functions. The calculated result agrees with the oversea experimental one.The research shows that the shaft can decrease air pressure in tunnels, and its section area and position have a great effect on the pressure.