车轮扁疤引起的轮轨冲击分析

为了研究高速列车车轮扁疤引起的动力学问题，根据多体动力学理论和等效轨道激扰法，建立了我国某型高速车辆的动力学模型及车轮新、旧两种扁疤模型.应用车轮轮径变化扁疤模拟法对车轮扁疤进行模拟，并对高速车辆轮轨冲击动力效应进行仿真分析.结果表明:新、旧扁疤轮轨冲击力规律不同，旧扁疤产生轮轨垂向冲击力随车速的增大而增大，在高速运行条件下，远大于新扁疤产生的垂向冲击力；当车速分别高于200和250 km/h时，车轮扁疤长度需要限制在35和30 mm以内. 

Analysis of Wheel/Rail Impact Induced by Wheel Flats

In order to study the dynamic issues induced by wheel flats for high speed trains, a dynamic model and new/worn wheel flat models were developed using the multi-body theory and the equivalent track excitation method. The simulation method considering the change of wheel radius was applied to simulate the wheel flat and analyze the wheel/rail impact caused by wheel flats. The results show that the behaviors of wheel-rail impact forces caused by new and worn wheel flats are different: the impact force caused by a worn flat increases with the train speed increasing, and is significantly larger than that by a new flat at high speeds. When the running speed of the train is larger than 200 and 250 km/h, the length of the wheel flat should be limited within 35 and 30 mm, respectively.