车轮多边形情况下轮轨接触算法

接触斑的法向应力分布是轮轨动力学分析和轮轨磨耗计算的基础。铁路车辆采用的磨耗型踏面出现多边形时，接触点处的轮轨横向曲率和纵向曲率都随接触位置的变化而变化，此时最常用的赫兹接触方法的精度难以保证。非赫兹方法的计算精度高，但其效率不能满足工程计算要求。应用非赫兹方法分析了车轮多边形引起的轮轨纵向曲率变化对接触斑的影响，发现当车轮多边形波长大于65 mm时，多边形对接触斑应力分布的影响可忽略不计。然后提出了改进的半赫兹方法，并对不同接触位置的接触斑形状和应力分布进行对比分析，结果表明：多边形波长大于65 mm时，改进的半赫兹方法在与非赫兹方法的结果保持一致的同时，大大缩短了计算时间。

Study on the contact algorithm of the polygonal high-speed rail wheels

The normal solution of the contact patch is the base of vehicle system dynamics as well as wear calculation. When the wheel polygonization appears on the worn-type wheel of the train, the lateral and longitudinal relative wheel/rail curvature around the contact patch will vary significantly. The widely used Hertzian contact method will be imprecise because the strong hypothesizes cannot be well satisfied. The non-Hertzian method is precise but too time-consuming for application. The influence of the wheel polygonization on the contact patch was analyzed, then an improved semi-Hertzian method was proposed. By studying the shape and the pressure distribution of the contact patches at different contact positions, it is found that when the wavelength of the wheel polygonization is larger than 65 mm, the results of the improved semi-Hertzian method can agree well with the non-Hertzian method with reasonable computing time.