A Study of Crosswind Characteristics on Aerodynamic Performance of High-Speed Trains on Embankment

This study numerically investigates the effects of crosswind profile on the aerodynamic loads of a high-speed train (HST). The primary purpose of this work is to evaluate the impact of different characteristic crosswinds on the HST operational safety by using Reynolds-averaged Navier–Stokes (RANS) turbulence models. The numerical calculated aerodynamic coefficients show good agreement with the experimental data of a wind tunnel test. The results indicate that the vortexes on the leeward side of the HST grow along the train and gradually move away from the train body along the longitudinal direction. When the yaw angle keeps constant, the aerodynamic loads increase significantly on a higher embankment, and the operational safety deteriorates consequently. When the HST runs in a power law crosswind environment which is formed by different ground roughness, the aerodynamic loads on the HST decrease with the increase of the roughness. For instance, when the HST running in the power law crosswind environment with ground roughness of 0.12, 0.15, 0.22 and 0.30, the corresponding overturning moment coefficients of the train can be 2.774, 2.708, 2.658 and 2.550, respectively, indicating 7.4%, 8.6%, 10.3% and 14.0% reductions, as compared to those under the uniform wind profile. It is more accurate to use power law wind field when evaluating the operational safety of HST. The results in this paper can provide certain guiding significance for the safety assessment of the HSTs running on the embankment under crosswinds.