A passive flow control method with winglets installed on leeward side of a high-speed train for improvement of anti-overturning performance under crosswinds

With higher train speed and advancements in lightweight technology, the crosswind environment poses a growing threat to train safety. This study recommends installing novel winglets along the train's sidewall to improve the flow structure on the leeward side. In order to decrease the overturning moment and enhance running safety and stability, this method aims to increase the lift force and decrease the lateral force of the train. To lessen the negative impact of the low-pressure leeward vortex on the train's aerodynamic performance, the winglets produce new vortex structures that interact with the preexisting vortex structure and suppress its development. By increasing the pressure on the leeward side and optimizing the structure of the flow field, the lateral force and overturning moment are reduced by 18.93% and 27.61%, respectively. In addition, there is a 22.68% increase in the lift force. Consequently, the use of the novel winglets can substantially reduce the effects of crosswind on high-speed trains.