The effect of wheel rotation on the aerodynamic performance of a high-speed train

Based on a CRH3 model consisting of three cars, cases whose wheels are set as the relative-rotation and relative-stationary boundary conditions were numerically studied at train speeds of 360, 420, 500km/h. The effect of wheel rotation on the aerodynamic performance for each part and the whole of the high-speed train model was analyzed. The results indicate that the effect of the wheel rotation has little influence on the aerodynamic drag, but a significant influence on the aerodynamic lift for each part and the whole of the train model. If boundary conditions of the wheels are changed from the relative rotation to stationary, the whole aerodynamic drag coefficient would have a one percent reduction, the whole aerodynamic lift coefficient would have a fifteen percent reduction, and the aerodynamic lift coefficient of the last car would have a seven to eleven percent reduction. The model with relative-rotation of the wheels should be adopted for accurate simulations of the aerodynamic lift for each part and the whole high-speed train.