典型路基结构对高速列车横风气动特性影响分析

Influence of Typical Subgrade Structures on Aerodynamic Characteristics of High Speed Trains in Cross wind Conditions

由于地域及环境的限制,高速铁路采用多种路基结构如平直地面、不同高度路堤、高架桥等,当列车运行在路堤及高架桥上时,车体周围的绕流流场比平直地面更加复杂。在强横风的作用下,不同的路基结构上的高速列车横风气动特性存在明显差异,不合理的路基结构将影响列车的横风安全性。同时列车结构复杂,转向架、受电弓等都对列车的流场特性有重要作用,过于简化的短编组列车外形不能够精细反映列车的真实气动特性。为研究典型路基结构对高速列车横风气动特性的影响,以9编组动力集中型高速列车实车为研究对象,考虑风挡、转向架、受电弓等细节特征,对列车运行速度为200 km/h,横风速度分别为20 m/s、30 m/s、35 m/s、40 m/s,路基结构分别为平直地面、3 m路堤、6 m路堤、高架桥等四种场景下的高速列车空气动力学性能进行了仿真计算和对比,分析了不同路基地面条件下列车的横风气动特性的差异及规律,为横风条件下复杂路基结构的列车运行安全控制提供了参考。

Due to geographical and environmental constraints, high-speed railways use a variety of roadbed structures such as flat ground, different height embankments, viaducts, etc. When trains run on embankments and viaducts, the flow around the car body is more complex than the flat ground. Under the action of crosswind, there are obvious differences in the cross-wind aerodynamic characteristics of high-speed trains on different subgrade structures. The unreasonable subgrade structure will affect the cross-wind safety of the train. At the same time, the structure of the train is complex, the bogie and pantograph have an important role on the flow field characteristics of the train, and the over simplified profile of the short train cannot accurately reflect the true aerodynamic characteristics of the train. In the present paper, in order to study the influence of typical roadbed structure on the aerodynamic characteristics of high speed trains, a real high-speed train with 9 carriages at the speed of 200 km/h was taken for case study, and the details of windshields, bogies and pantographs were taken into consideration. The cross wind velocities were chosen as 20, 30, 35 and 40 m/s. The aerodynamics performance of the high-speed train under the four conditions of plane ground, 3 m-embankment, 6 m-embankment and viaduct were simulated and compared, and the differences and regularities in the aerodynamic characteristics under cross wind conditions on different subgrade were analyzed. The results provide a reference for train safety control on complex subgrade structures under cross wind condition.