用摄动法求解轮轨空间两点接触变拓扑的解析式

建立了轮轨空间几何接触的精确模型，用伪弧长延拓法得到精确数值解，采用摄动法，以轮对摇头角为摄动参烽，并根据累轨接触对称性的特点，计算出摇头角对接触点坐标和广义坐标的影响系数，得到轮轨从一点接触到两点接触变拓扑切换条件的解析式。从影响系数的解析解还可以看到，在摇头角一定的情况下，轮缘接触点纵向坐标的大小是由轮缘接触角决定的，为轮轨踏面参数优化提供了依据。

Perturbation Method to Determine Changing Condition of Wheel/Rail Two Points Contact with Changing Topology

Based on the three dimensional wheel/rail two points contact model and the exact numerical solution,perturbation method is used to get the changing condition when the two points contact occurs.From the analytical expression of the influence coefficient,it is found that the longitudinal coordinate on the flange changes greatly with the yaw angle.These results can be used to optimize the W/R parameters,and to give the necessary data for dynamics simulation.