横向风作用下高速铁路车桥系统绕流特性分析

基于不可压缩二维雷诺平均N-S方程，采用RING（renormalization group）k-ε两方程湍流模型，对德国ICE（intercity-express）列车和标准简支梁组成的车桥系统在横向风作用下的二维绕流特性进行了分析．计算网格为由三角形非结构网格和四边形结构网格组成的混合网格，采用有限体积法对微分方程进行离散，应用SIMPLE算法解决压强-速度耦合关系．根据高速铁路桥梁带挡风墙的特点，引入空腔流动研究成果对车桥系统的绕流特性进行了理论分析．结果表明，高速铁路桥梁挡风墙的挡风机理在于充分运用了空腔流的旋涡特性．

Analysis of Flow Characteristics around High-Speed Railway Bridge-Vehicle System under Cross Wind

An analysis was carried out for flow characteristics around a vehicle-bridge system consisting of German ICE(intercity-express) vehicle and standard simplysupported bridge under cross wind.Based on the two-dimensional Reynolds averaged incompressible Navier-Stokes equations,the RNG(renormalization group) turbulence model was used in the numerical simulation.Triangular grid and quadrilateral grid were used to divide the computational domain,the finite volume method was adopted to discretize the governing differential equations,and the pressure-velocity field was coupled using the SIMPLE(semi-implicit method for pressure-linked equations) algorithm.Furthermore,the research results of driven cavity flows were applied to the analysis of flow characteristics around the vehicle-bridge system considering the wind-break wall effect.The analysis shows that the wind-break wall of a high-speed railway bridge has the similar vortex characteristics of driven cavity flows in preventing wind.