Research on Aerodynamic Loads Caused by Maglev Train Entering Tunnels Under Crosswinds

Strong crosswinds and train–tunnel aerodynamic interactions cause the aerodynamic loads acting on the train body to change more drastically when a high-speed maglev train enters a tunnel. This greatly raises the risk of safety incidents like derailment or overturning. This study employs the FLUENT 2023 R2 computational fluid dynamics simulation software with an overset grid method to numerically investigate the influence patterns of crosswinds on aerodynamic loads and relevant safety issues for a 600 km/h maglev train entering tunnels under various crosswind conditions. The findings show that (1) the marshaling location has a strong correlation with aerodynamic performance. When there is no crosswind, the head vehicle (HV) has the greatest chance of flipping, while the rear vehicle (RV) has the worst lift characteristics. All three vehicles experience significant sudden changes in lateral force coefficients prior to tunnel entry, indicating considerable derailment risks. (2) Aerodynamic loads on the HV show significantly greater sensitivity to crosswind velocity variations compared to the middle vehicle (MV) and RV, with the amplitude reduction in lateral forces in the HV showing approximately linear increase with wind speed. (3) A 50 km/h reduction in train speed decreases the amplitude of change in the lift coefficient and lateral force coefficient by approximately 4.8% and 8.9%, respectively, and the peak overturning moment in open air and tunnel by approximately 11.4% and 15.7%, respectively. These discoveries have both practical value for advancing high-speed maglev networks and theoretical significance for enhancing the safety and reliability of Chinese maglev systems.