Numerical study on the effect of damaged windows on aerodynamic characteristics of passenger trains under strong crosswind

Abstract

Sand and gravel blown up by strong wind will cause damage to windows. Following up, it will cause the change in the flow field around a train immediately, which has a significant impact on the aerodynamic performance of the train. Delayed detached-eddy simulation based on the shear stress transport κ-ω turbulence model was used to investigate the aerodynamic characteristics of passenger vehicles under crosswind, and the effect of damaged windows on the train aerodynamic performance and flow field around the train was analyzed and compared. The grid generation and numerical method are verified in the previous studies. Results show that the aerodynamic performance of a passenger vehicle is significantly affected by damaged windows on both sides of the passenger vehicle, both the aerodynamic lateral force and overturning moment of the passenger vehicle were decreased, and this has a small effect on the aerodynamic performance of the downstream passenger vehicle. Fluctuation of the aerodynamic lift, lateral force, and overturning moment of a vehicle with damaged windows on both sides of the vehicle is significantly increased. Damaged windows do not change the existence of the main vortices around vehicles, but the size, location, and strength of the main vortices are obviously changed, especially when windows on both sides of the vehicle are damaged. Therefore, when windows on the windward side of the vehicles are damaged, opening or broking windows on the leeward side of the vehicles will help reduce the risk of vehicles overturning and derailment.