高速轮轨水介质存在下的黏着特性数值研究

NUMERICAL STUDY ON ADHESION OF WHEEL AND RAIL AT HIGH SPEED UNDER WET CONDITION

为了获得高速轮轨在水介质存在时的黏着特性,该文建立了三维轮轨间存在水介质时考虑表面粗糙度的轮轨黏着计算模型。该模型以部分弹流理论及弹性微观固体接触模型为基础,借助于多重网格作为数值计算工具。研究了水介质存在时列车运行速度、轴重及轮轨表面粗糙度对轮轨黏着系数的影响,并从数值角度揭示了其影响机理。计算结果表明,随着速度的提高,黏着系数逐渐降低;随着轴重的增大,黏着系数逐渐降低;适当地增加轮轨表面粗糙度有利于增加轮轨黏着特性。

A three-dimensional wheel/rail adhesion numerical model under wet condition, which considers surface roughness of wheel and rail, was established to obtain the characteristics of wheel/rail adhesion at high speed. Based on the partial elasto-hydrodynamic lubrication(EHL) and elastic micro asperity contact theory, multi-grid method was employed as a numerical tool for solving the established model. The effects of train speed, axle load and surface roughness on the adhesion between wheel and rail were investigated, and then explained from the numerical aspects. The results show that the adhesion coefficient decreases with the increasing of train speed. It is also shown that the adhesion coefficient decreases with the increasing of axle load. Properly increasing surface roughness is benefit to the characteristics of wheel/rail adhesion.