轮对-轨道系统波磨预测模型的建立及预测分析

Establishment and Prediction Analysis of the Rail Corrugation Prediction Model for Wheel-rail System

基于摩擦自激振动导致钢轨波磨的理论,通过轨下垫板等效替代扣件系统,建立轮轴之间采用过盈配合的轮对-轨道系统的有限元预测模型,采用复特征值分析法预测轮轨系统的摩擦自激振动。通过对比所建模型和采用弹簧阻尼对模拟扣件的模型之间的差异,发现所建模型在预测效果上更接近现场测试结果。通过控制变量法研究摩擦因数、轨下垫片等效弹性模量对波磨预测结果的影响。仿真结果表明:摩擦因数在0.2~0.6范围内时,随着摩擦因数的增大波磨发生的可能性会增加;扣件垂向刚度在50~90 MN/m范围内时,随着扣件刚度的增大即轨下垫板等效弹性模量的增大,系统发生不稳定振动的可能性会降低。仿真预测与实验结果一致,进一步验证了模型的有效性。

Based on the theory that the frictional self-excited vibration leads to rail corrugation,a finite element prediction model of the wheel-rail system with interference fit between wheel and axel was established by equivalent substitute fastening system through rail pad.The complex eigenvalue analysis method was used to analyze the frictional self-excited vibration of the wheel-rail system.The prediction result from the model as established was compared with that from the model that uses spring-damper pairs to simulate fasteners.It is found that the prediction result from the model as established is closer to the field test result.The influence of the friction coefficient and the equivalent elastic modulus of the rail pad on the prediction results of corrugation were studied by the controlled variable method.The simulation results show that when the friction coefficient is in the range of 0.2 to 0.6,the possibility of rail corrugation will increase with the increase of friction coefficient.When the vertical fastener stiffness is within the range of 50 MN/m to 100 MN/m,with the increase of fastener stiffness,that is,with the increase of equivalent elastic modulus of rail pad,the possibility of unstable vibration of system will decrease.The prediction result is consistent with the field measured result,which proves the effectiveness of the model.