Track Mechanical Analysis under Strong Cross Wind Based on Fluid-Solid Coupling

In order to explore the mechanical characteristics of track structure under strong cross wind, the co-simulation of CFD and FEM is used to analyze the force and deformation of track structure. Firstly, SOLIDWORKS is used to establish a model based on the CRH380A high-speed train. Then, the aerodynamic characteristics of the train are calculated by FLUENT and the train-track coupling model is established by finite element software ABAQUS. The aerodynamic force on the surface of the train is completely retained in the model, which has solved the problem of aerodynamic force transfer in the fluid-solid coupling. Finally, based on the established coupling model, the mechanical characteristics of the track structure under strong cross wind are analyzed. The results show that when the train running speed is up to 350 km/h and the wind speed changes from 0 to 15 m/s, the lateral displacement on the leeward side of the rail increases from 0.177 mm to 2.100 mm, which increases by 11.86 times. This indicates that the mechanics of the rail leeward side should be focused. When the wind speed exceeds 15 m/s and the train operation speed is 250 km/h, the rail lateral displacement is beyond the allowable maximum of 2.000 mm, showing that long-term cross wind will lead to track geometry change. However, the rate of wheel load reduction and the coefficient of derailment is not up to the limit of 0.65 and 0.800, respectively. Therefore, it is necessary to consider not only the safety index of train operation, but also the change in the mechanical characteristics of track structure.