Study On Cross-Wind Safety Of High-Speed Train

With the continuous increasing of operation speed, lighting of train weight and extending of running range, high-speed train operational safety in cross-wind is facing unprecedented challenges. Since the complete safety evaluation system for high-speed train on cross-wind has not been set up in China and there are special operation environments such as Lanzhou-Xinjiang rail line, randomness and pulsation of cross-wind are reinforced. So aimed at conditions where high-speed trains are applied in China, the study of high-speed train cross-wind safety has the extremely significance. In this paper, the safety of high-speed train in cross-wind is studied, with establishing a vehicle nonlinear dynamics detailed model of the first coach in the train and three different wind load models.First of all, the vehicle dynamics simulation model of the first coach in high-speed train (trailer) is set up considering the flexibility of car body, equipment under the cabin and various nonlinear factors. Respectively based on the assumption of constant wind, the transient wind effect and the randomness of wind, a steady static wind load model, a "Chinese hat" transient wind load model and the unsteady random wind load model are established. And according to the theory of quasi static and synthesis theory of wind speed, the aerodynamic load is acted on the vehicle dynamics model as external excitation load.Then, with the dynamics simulation and calculation, safety indexes such as the derailment coefficient, wheel set reducing load rate, overturning coefficient and lateral force between wheel set and axle are obtained. And based on these safety indexes, the influence of track excitation and curve line on the safety of train in cross-wind is studied. After that, according to the standards and norms related to vehicle dynamics, the critical wind speed under the limit of safety indexes is obtained. And according to the critical wind speed, the index suitable for evaluating high-speed train operation safety in cross-wind is proposed. By analyzing and comparing with test and simulation, equivalent simplified model of turbulent wind on the Lanzhou-Xinjiang rail line is researched. According to the critical wind speed of vehicle derailment, the safety margin with safety indexes in various wind load models is analyzed.The influence of three wind load models on stability of cross-wind vehicle hunting is studied by calculating the nonlinear critical vehicle speed with different wind load models. The one-way cross-wind’s impact on partial mill of wheel and the cross-wind safety in case of partial wearing wheels are researched. And the influence of three kinds of wind load models and track excitation on cross-wind vehicle gauge is compared and analyzed by calculating the offsets of gauge control points with different wind load models, and wind load model suitable to calculation of vehicle gauge on cross-wind is proposed.