重载钢轨磨耗预测模型及接触斑网格密度研究

Rail Wear Prediction Model and Grid Density of Contact Patch for Heavy Haul Railway

摘要:

基于车辆-轨道耦合动力学及轮轨滚动接触分析，结合材料磨损理论建立了钢轨磨耗预测模型，编制了计算程序，可实现钢轨磨耗具体分布及发展的定量预测分析.鉴于轮轨接触斑离散化网格密度在预测模型中的显著影响作用，从接触力、磨耗分布等方面对这一因素的影响机理进行分析，探讨合理的接触斑网格密度.研究结果表明：网格密度不影响计算结果的正确性，但是稀疏的网格密度得到的蠕滑力及磨耗分布存在较多尖锐形状突变，增大密度可提高精度及磨耗分布平滑性，但会成倍增加计算代价；网格密度20×20时，钢轨磨耗速率变化由剧烈趋于稳定，继续增大密度改善效果已不明显，建议预测模型中接触斑网格密度取20×20，在确保精度的同时尽可能拥有较高计算效率.

关键词:车辆-轨道耦合动力学; 轮轨接触; 接触斑网格密度; 钢轨磨耗

Abstract:

Based on vehicletrack coupling dynamics and wheelrail rolling contact analysis, a rail wear prediction model was developed combining the material wear theory and the corresponding calculating program was written, which can quantitatively predict the distribution and development of rail wear. In view of the significant effect of discrete grid density of wheelrail contact patch on the prediction model, the influencing mechanism of the factor was analyzed from the perspectives of contact force distribution, wear distribution and so on. The reasonable grid density of contact patch was discussed. The research results show that the grid density does not affect the correctness of calculated results, but sparse grid causes many sharp shape changes in the creeping force and wear distributions. Increasing the grid density can improve the precision and smoothness of wear distribution, but the computation cost increases dramatically. When the grid density increases to 20×20, the change of rail wear rate tends to be stable. Continuing increasing the density does not bring about obvious improvement. Therefore, a grid density of 20×20 is suggested in the prediction model, which can achieve a high computation efficiency and accuracy.

Key words:vehicle track coupling dynamics; wheelrail contact; grid density of contact patch; rail wear