轮轨振动行为下高速轮轨滚动接触瞬态特性分析

Transient Characteristics Analysis of High-Speed Wheel-Rail Rolling Contact under Wheel-Rail Vibration

以CRH2型高速列车头车为研究对象,在轮轨滚动振动接触简化模型的基础上,采用多体动力学软件UM建立高速列车多体动力学数值模型,求解轮轨振动行为下的接触参数并作为有限元分析的输入;采用有限元方法建立高速轮轨滚动接触瞬态有限元模型,对轮轨振动行为下的高速轮轨滚动接触瞬态特性进行分析。结果表明:轮轨的垂向振动明显,轮轨垂向力呈周期性变化,且周期约为0.1s,振动频率约为10 Hz,轮轨垂向力最大为115 751.8N、最小为688.4N,分别为轮轨静载荷的1.938倍和0.012倍;轮对横移的振动频率约为1.05Hz,振幅为5.26mm;轮对横移量在0.5s时最大,为0.2s时的7.17倍,但纵、横向蠕滑力在0.2s时的大于0.5s时的;不同时刻轮轨间纵、横向蠕滑力的均值分别为13 542.11和1 239.07N;在一定范围内,纵、横向蠕滑力与轮轨垂向力、轮对冲角以及接触斑面积呈正相关。

Taking the head car of CRHe high speed train as the research object, on the basis of the simplified model of wheel-rail rolling contact vibration, the multi-body dynamics software UM was used to establish the multi-body dynamics numerical model of high-speed train. The contact parameters of wheel- rail vibration behavior were calculated and used as the inputs of finite element analysis. The finite element method was used to establish the transient finite element model of high speed wheel-rail rolling contact to analyze the transient characteristics of rolling contact under wheel-rail vibration. Results show that the vertical vibration of wheel and rail is obvious, and the wheel-rail vertical force varies periodically and the period is about 0. 1 s. The vibration frequency is about 10 Hz, the maximum wheel-rail vertical force is 115 751.8 N and the minimum is 688.4 N, which is 1. 938 times and 0. 012 times of the wheel-rail static load respectively. The vibration frequency of wheelset lateral displacement is about 1.05 Hz and the amplitude is 5.26 mm. The lateral displacement of wheelset is the maximum at the moment of 0. 5 s which is 7. 17 times of that at the moment of 0.2 s, but the longitudinal and transverse creep forces at the moment of 0.2 s are greater than those at the moment of 0.5 s. The mean values of wheel-rail longitudinal and transverse creep forces at different time are 13 542.11 and 1 239.07 N respectively. In a certain range, the longitudinal and transverse creep forces are positively related to the vertical force, wheelset attack angle and contact patch of wheel and rail.