The Influence of Different Cross-Section Shapes of Train Body on Aerodynamic Performance

Abstract

Abstract. In this paper, the influence of different cross-section shapes of train body on aerodynamic performance has been investigated by numerical simulations. Computational fluid dynamics (CFD) is used with the second-order finite volume method with SST k-omega turbulence model. The results indicate that the aerodynamic performance is strongly affected by different cross-section shapes of train body, such as cross-sectional area, width-to-height ratio of crosssection, cross-section with straight or curved sides, etc.. Firstly, the drag coefficient and the overturning moment increase as the sides of cross-section become more curved. Secondly, the drag coefficient and the overturning moment are reduced as the width-to-height ratio of the cross-section is increased when the cross-sectional area is kept as a constant. Finally, air pressure pulse produced by two trains passing by in tunnel is approximately proportional to the cross-sectional area in a certain range and is independent to the cross-section shapes. Numerical results can be used for aerodynamic shape design of high speed trains.

Numerical investigation of the pressure and friction resistance of a high-speed subway train based on an overset mesh method

“…The k-omega turbulence model can eliminate the adverse free flow issues of the Wilcox model, and the SST method is further developed by introducing an upper limit for the turbulent shear stress in boundary layers to avoid overpredicting the shear stress at the train surface. 30,31 The relevant control equations are solved using the CFD software STAR-CCM+ based on the finite volume method (FVM). In this work, the SIMPLE pressure-velocity coupling method is adopted.…”