Aerodynamic characteristics of a trailing rail vehicles on viaduct based on still wind tunnel experiments

The aerodynamic behavior of rail vehicles subject to crosswind has become one of the hot topics to the Chinese railway community, due to the rapid expansion of the high-speed railway networks in the last decade. To investigate the aerodynamic interference between vehicle and viaduct, models of a typical simply supported 32 m pre-stressed concrete box beam viaduct and CRH2 train with scale of 1:25 were tested in wind tunnel experiments. By using simultaneous pressure scanning technique, various tests combining different cases of vehicles on double tracks on the viaduct were carried out. Pressure measurements were performed on the trailing rail vehicle to avoid the three-dimensional effects of train nose. The influences of wind barrier height and porosity on the aerodynamic characteristics of the train were also addressed. The experimental results indicate that the wind pressure distribution on the trailing vehicle is almost uniform along its axial direction, while the aerodynamic influence of vehicles on different tracks (upstream and downstream tracks) is different. Moreover, the porosity and height of the wind barriers are found to require optimization for different configurations.