考虑轮对柔性的车轮疲劳寿命研究
Fatigue life of railway wheel based on rigid-flexible coupling dynamic model of vehicle system

以CRH2型动车组拖车车轮为研究对象,建立考虑轮对柔性的车辆系统刚柔耦合动力学模型,利用有限元法和Palmgren-Miner准则对车轮的疲劳寿命进行研究。利用有限元软件ANSYS建立轮对的有限元模型并生成轮对子结构模型;利用多体动力学分析软件SIMAPCK建立包含柔性轮对的车辆系统刚柔耦合动力学模型,得到轮对的动力学响应和受到的动荷载时间历程,并与车辆系统多刚体动力学模型的结果对比;基于名义应力和Palmgren-Miner准则对车轮的疲劳寿命进行研究。研究结果表明:考虑轮对柔性的车辆系统动力学模型能够得到更准确的车轮受到的动载荷时间历程;车轮首先发生疲劳破坏的部位发生在辐板和轮辋以及轮毂过度处,属非比例多轴疲劳破坏,并首先在辐板表面形成裂纹并逐渐向内扩展;车轮的疲劳寿命远大于设计要求的使用年限,大部分未磨耗的到限的车轮经探伤处理后可以回收再利用。
The wheels of the CRH2 trailer are taken as the research object, and a vehicle system dynamic model with flexible wheelsets was established. The finite element method and Palmgren-Miner rule were used to study the fatigue life of wheel. First, the finite element model of wheelset and its substructure model were obtained using finite element software ANSYS. Second, a rigid-flexible coupling dynamic model of vehicle system which contains four flexible wheelsets was established using multi-body dynamics software SIMPACK, andthe time history of loads and the dynamic response applied on the wheelset are obtained. The results were compared with the ones of multi-rigid vehicle system dynamic model. Finally, the fatigue life of wheel were analyzed based on nominal stresses and Plamgren-Miner rule. The results show that the time history of dynamic loads applied on wheels obtained by the vehicle system dynamic model with flexible wheelsets are more accurate ; the fatigue rupture emerges first at the transition between rim and wheel hub and is non-proportional multi-axis destruction. The fatigue life of wheels are longer than designed durable years, so most of wheels which do not reach the limit of abrasion could be recycled after flawdisposition