三维碰撞车辆移动轨道建模与研究

Modelling and Investigations of 3D Colliding Vehicles and Moving Tracks

为掌握直线轨道上车辆发生正面对心碰撞时的动态响应规律,建立三维碰撞车辆移动轨道模型。分别建立碰撞车辆模型和轨道模型。然后,提出了处理轮轨非线性几何的向量法,将三维车辆模型和移动轨道模型耦合起来。采用一种简化的钩缓装置模型连接车辆端部和外部系统。利用一种新的时间积分算法对三维动力学模型进行计算。采用上述方法研究了车辆中低速撞击刚性墙的碰撞场景,得到车辆的动态响应。研究结果表明:中低速车辆在直线轨道正面对心碰撞时,车辆一般不产生横向运动和侧滚运动,由非线性轮轨几何引起的横向轮轨力对车辆的动态响应几乎没有影响。碰撞结束后,车体和轮对在纵向不断振荡。轮轨垂向相对位移在准静态压缩量上下波动,最大的车轮抬升量出现在第3个轮对上。

In order to obtain the law of dynamic responses of vehicle front central collisions on straight tracks, a 3D model composed of a colliding vehicle and moving tracks is developed. The first step is to build the models of the colliding vehicle and the moving tracks. Then, a vector method is presented to address the nonlinear geometry of wheel and rail. The models of the 3D vehicle and the moving tracks are coupled through the nonlinear wheel-rail relation. A simplified model of coupler buffer device is applied to connect vehicle ends with outer systems. Finally, a novel time integration algorithm is used to calculate the results of the 3D dynamic model. The collision scenario that the vehicle impacts a rigid wall at a medium-low speed is studied based on the abovementioned method to obtain the dynamic responses of the vehicle. The results show that the vehicle does not generate lateral movements and roll movements when the vehicle collides without misalignment at medium-low speeds on straight tracks. Lateral wheel-rail forces induced by nonlinear wheel-rail geometry almost have no influence on the dynamic responses of the vehicle. The carbody and wheelsets of the vehicle continuously oscillate in longitudinal direction in the end of the collision. The vertical relative displacements of wheel and rail fluctuate around the quasi-static compression value. The maximum value of wheel rise occurs on the third wheelset.