Abstract: It is also very important to improve resistant capabilities of wind resistance and structural stability of the windbreak while reducing train aerodynamic load. A new type of windbreak is proposed with double-layer structure forming a cavity chamber with hole for energy dissipation of crosswind. Numerical simulation is used to analyse and compare the effects of two kinds of windbreak in the reduction of aerodynamic force acting on the train and their own wind-resistance performance. The results show that the two types of windbreaks can significantly reduce the train aerodynamic load under the action of crosswind, and of course, there is obvious difference between them, and the aerodynamic force acting on the windbreak with cavity chamber structure is small than on another one with single layer structure. The new windbreak has better effect in aerodynamic load shedding for the train, stronger resistant capabilities of wind resistance and structural stability. By changing the aperture ratio of leak hole on the two layer plates, force distribution on them can be adjusted for the windbreak with chambers. This new type of windbreak is a new idea and will provide some useful references for design of the wind protection system for high speed train.

Key words: high-speed train;cross-wind;windbreak;air chamber dissipating energy;wind resistance