Evaluation of active leeward side air-blowing layout on the lateral aerodynamic performance of high-speed trains in crosswinds environment: Sustainable and safe operation strategy

The lateral aerodynamic forces experienced by high-speed trains operating in crosswind environments affect trains' operating safety significantly. This paper used the Improved Detached Eddy Simulation (IDDES) method based on the Shear Stress Transport (SST) k-ω turbulence model to explore the mitigating effect of air-blowing at the leeward side of the train on the train's lateral aerodynamic forces. Different air-blowing positions and speeds were considered. The results indicate that the best mitigating effect can be achieved when simultaneously blowing air at the head, middle, and tail cars; in addition, when blowing air at the speed of 0.3 times of the resultant velocity, the rolling moment of the three cars reduced by 7.71%, 7.25%, and 25.46% respectively. Finally, the assessment of the mitigation efficiency was displayed to discuss the trade-off of rolling moment reduction and energy utilization rate for air-blowing. The research gives an insight into increasing the stability and safety of trains in crosswind based on active control, which can improve the safe operation threshold of trains.