地铁线路曲线段磨耗状态下轮轨滚动接触有限元分析

Wheel-rail Rolling Contact Finite Element Analysis of the Wear State on the Curve of Subway Line

基于城市轨道交通曲线段不同磨耗程度的典型钢轨和车轮的实测型面,利用有限元分析软件ANSYS建立曲线段轮轨三维弹塑性接触有限元模型,对三种不同轮轨磨耗型面匹配工况下的地铁车辆的曲线通过性能以及轮轨接触应力进行计算分析,分析不同磨耗状态下车轮和钢轨接触时的接触应力和轮轨应力的分布状态,并研究其对钢轨磨耗的影响。发现钢轨使用初期,由于轮轨廓形不一致,轮轨间易出现应力集中,应力集中部位易出现磨损;随着钢轨侧磨的增加,轮轨接触状态逐渐由一点接触变为两点接触,且接触点的塑性变形部分和弹性部分的过渡区间易出现裂纹;两点接触状态下,外侧轨距角处接触面积及应力集中区域远大于钢轨侧面部分,轨距角易出现较大的接触压力,易加速钢轨磨耗与疲劳伤损的产生。

Based on the measured rail and wheel profiles of different wear depth of rail on the curve of urban rail transit, using the finite element analysis software, ANSYS, we establish wheel-rail contact three-dimensional elastic-plastic finite element model and then analyse the metro vehicle’s performance, the distribution of wheel-rail contact stress state and its impact on the rail wear under the matching of new wheel’s profile and three kind of rail’s profile. It is prone to have stress concentration on wheel/rail’s contact area because of their profiles’ inconsistency in the early of the rail’s use. And this kind of concentration causes the wear on rail more easily. With the increasing of the rail side grinding, the contact status of wheel and rail gradually change from one-point contact to two-point contact. It is easy to crack on the transition zone between plastic deformation and elastic area of the contact point. Under the two-point contact status, it is easy to arise larger contact pressure on gauge corner because that the outer gauge corners contact area and stress concentration area are much larger than the rail side section. The rail wear and fatigue injury is also more easy to generate in this status.