Computational study of aerodynamic characteristics of high-speed trains under cross wind conditions

The impact of the aerodynamic characteristics of high-speed railway trains under cross wind conditions becomes more and more important. Numerical simulation of high Reynolds number flows past complex train geometry at angles up to about 45 was carried in this paper. Research shows that, on the upper leeward side near the leading nose, the separation line does not originate from a singular point, and the separation belongs to 'open separation'; on the tail nose the separation line ends in a focus. The leeward vortexes dominate the flow alternately along the stream direction, which generate a large side force and rolling moment and deteriorate the stability of the train. Moreover, the aerodynamic loads and stability of each car are discussed in the end.