Influences of Underbody Structures on Flow Field and Aerodynamic Optimization Laws of High Speed Train

Abstract:

In order to obtain the influence of underbody structures on flow field and aerodynamic drag optimization laws of high speed train, the computational fluid dynamic and the orthogonal experimental analysis methods were adopted to studied underbody flow field, wake and the optimization law in complex train model. The results indicated that the pressure coefficient drops 0.06 in nose region of the tail car, and bogies moved the flow separation of the tail car ahead. The distances and the angle between antisymmetric wake vortices cores increased. The simplified topology model in concept design was suitable for aerodynamic optimization in complex train model design. However underbody structures decreased the optimization range of the head car, and increased the parameter optimization range of the tail car. The drag reduction of the head car should focus on bogie sections, and drag reduction of the tail car was more sensitive to streamline length.