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. •A novel blowing method to mitigate the lateral aerodynamic performance of high-speed trains in crosswinds.•Effects of blowing air on the train's surface pressure and the airflow around the train are studied and explained mechanically.•Energy loss of blowing air is examined to evaluate the necessity of further increasing the blowing speed.