Aerodynamic characteristics of the train under real wind gust.

This article focuses on the numerical investigation of aerodynamic loads and flow field characteristics of trains under real wind gust conditions using the one-minus-cosine wind gust model and improved delayed detached eddy simulation (IDDES) based on the shear stress transport (SST) k–ω turbulence model. The study reveals that peak aerodynamic loads during wind gusts generally do not reach levels observed under constant crosswind due to the transient nature of gusts preventing fully developed stable flow fields. It highlights differences in aerodynamic responses between wind gusts with and without zero-crossing, noting greater discrepancies between unsteady and quasi-steady peaks for side force, rolling moment, and yaw moment under gusts with zero-crossing, and a delayed aerodynamic response particularly in the tail car attributed to wake flow dynamics. The research provides detailed aerodynamic load data and flow field analyses that contribute to understanding train stability and safety under complex wind conditions, while suggesting further studies on gust length effects, turbulence modeling, and multibody dynamic characteristics for comprehensive safety assessments.