Numerical simulation has been performed to investigate the flow around the high speed train under side wind conditions, and the yaw angle of 8. 77°is mainly focused. The model used is a scaled model in wind tunnel, with a scaled factor of 1:8. To compute numerically the complex flow structures, the three dimensional Reynolds-averaged Navier-Stokes equations, combined with the k-w SST model, were solved on hybrid grids using a finite volume technique. A comparison study between numerical results and experimental results has been conducted. Considering that the common CFD codes are still considered to be immature for the prediction of cross-wind stability, this paper delivers a comparative study between different commercial CFD software and tries to give best-practice recommendations for the investigated type of application. Furthermore, influence due to different meshes has been performed. Based on the best-practice results, the cross-wind characteristics of the high speed train have been mainly focused on. Both the fluid field characteristics and aerodynamic forces in cross-wind conditions are discussed.%采用雷诺平均的方法对高速列车横风稳定性进行了数值模拟,重点研究了列车在侧偏角为8.77°下的横风特性.研究对象为高速列车的风洞缩比模型,将数值计算结果与实验值进行了对比.鉴于当前各类软件针对复杂列车车体横风稳定性的计算仍然不成熟,首先进行了三类商用软件的数值计算比较,分析了不同软件计算结果的精度差异.针对复杂列车外形的网格划分也是数值计算中的重要组成部分,针对两套列车网格进行了分析,研究了网格对计算精度的影响.在与实验值拟合最好结果的基础上,还着重研究了列车在横风作用下的气动特性.背风侧上下侧面拐角位置的流动分离是横风效应的最明显特征,由于流动分离而产生的涡系沿着列车背风侧向下游延伸,并且其强度也不断增强.本文还从气动力角度对横风特性展开了研究.横风条件下列车气动力与无横风相比有较大差异,对列车不同部位的气动力及其组成等进行了分析.
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