Mitigating crosswind response of a high-speed train passing the end of windbreak walls

Abstract

The sudden change in wind speed at the end of a windbreak wall poses a significant threat to train safety, as it amplifies train’s responses. This study aims to investigate countermeasures to reduce the maximum unsteady crosswind response of high-speed trains at the end of windbreaks. Wind flow around windbreak walls was systematically examined by particle image velocimetry (PIV), considering both constant and varying porosities. Subsequently, a gust model was proposed to evaluate the wind distributions behind windbreak walls, validated by experimental results. Aerodynamic forces on high-speed train, incorporating windbreak walls with diverse porosities, were assessed by integrating the gust model and the quasi-steady theory. Ultimately, the unsteady crosswind responses were computed employing multibody simulations (MBS), accounting for both solid windbreak walls and those with varying porosities. A noteworthy finding was the reduction of approximately 25 % in the maximum unsteady crosswind response when windbreak porosity varied from 0 % to 80 %, thus affirming the efficacy of windbreaks featuring varying porosities in diminishing unsteady crosswind response. Overall, this study provides valuable insights into the design of windbreaks for high-speed trains, which can improve their safety and performance in strong wind regions.