柔性轮对的轮轨静态接触和车辆动态性能研究

Research on Wheel-rail Contact Geometry Relation and Vehicle Dynamic Behavior of Flexible Wheelset

分别研究了考虑轮对柔性时对轮轨静态接触几何关系和车辆动态性能的影响。首先在假设车轮不变形的前提下,将车轴简化为欧拉-伯努利梁模型,并以LM磨耗形踏面和标准60钢轨为研究对象,求解车轴运动微分方程以获得车轴的变形信息,再基于传统迹线法自编程序进行几何计算,求解变形后的轮轨接触几何参数,并与刚性轮对进行对比。结果表明,在横移量较小的情况下,柔性轮对与刚性轮对接触几何参数差别不大,当横移量较大时,两者有明显差异。其次,在车辆-轨道系统动力学模型中,利用模态叠加法将轮对考虑为柔性,并利用自编动力学积分程序计算常规工况和初始不称重特殊工况,分析其对轮轨力和一系悬挂力影响。结果表明常规工况下考虑轮对柔性的影响较小,而在特殊工况下,由于激励覆盖频率较高,柔性轮对的固有模态容易被激发,对轮轨力和一系悬挂力造成明显影响。

The effects of flexible wheelset on wheel-rail static contact geometry and dynamic vehicle performance are studied respectively.First,this paper simplifies the axle as the Euler-Bernoulli beam model under the assumption that the wheel is not deformed.The research object is LM profile tread and 60 rail.By solving differential equation of axle’s motion,the mathematical information of axle’s deformation is determined.Based on this information and the conventional wheel-rail contact line method,the wheel-rail contact geometry parameters of flexible wheelset are solved.By comparing the flexible and rigid wheelsets,results show that there is no obvious difference when lateral displacement is small.When lateral displacement increases,differences is becoming obvious.Secondly in the dynamic model of vehicle-track system,the wheelset is considered as flexible by modal superposition method.The self-compiled dynamic integral program is used to calculate the normal working condition and the special working condition of initial weightlessness and analysis the influence of flexible wheelset on wheel-rail force and primary suspension force.The results show that the influence of wheelset flexibility under normal working conditions is small.Under special conditions,the natural modes of flexible wheelsets are easily excited due to the high frequency of excitation which lead to obvious differences of wheel rail force and primary suspension force.