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基于有限元法和移动热源法,建立了轮轨摩擦非稳态传热计算模型,分析了车轮全滑动工况下三维模型和二维模型计算结果的异同,以及轮载、摩擦系数和相对滑动速度对钢轨摩擦温升的影响。结果表明,二维模型能模拟轮轨摩擦过程中钢轨纵截面温度变化规律;三维模型不仅能模拟钢轨纵截面温度变化规律,而且能模拟摩擦热的横向分布规律。车轮滑动过程中,摩擦热在轨面上引起的热影响区宽度在接触斑横向宽度范围内;接触斑中心处热影响层最厚,越靠近横向两侧,热影响层越薄。轮重不仅影响钢轨表面最高摩擦温升,而且影响热影响区域的大小;相对滑动速度越大,热影响层深度和宽度分别变浅和变宽;摩擦系数越大,热影响区越大。
Based on the finite element method and the moving heat source method, the heat transfer model of wheel-rail friction is established. The similarities and differences between the three-dimensional model and the two-dimensional model under the condition of full wheel slip are analyzed, and the relationship between wheel load, friction coefficient and relative slip Effect of Speed on Rail Friction Temperature Rise. The results show that the two-dimensional model can simulate the temperature variation of rail longitudinal section during wheel-rail friction. The three-dimensional model can not only simulate the temperature variation of rail longitudinal section, but also simulate the transverse distribution of friction heat. During the wheel sliding, the width of heat affected zone caused by frictional heat on the orbital plane is within the transverse width of contact patch. The thickest heat affected zone at the center of contact patch, the thinner the heat affected zone is. The wheel load not only affects the maximum friction temperature rise of the rail surface, but also affects the size of the heat affected zone. The larger the relative sliding velocity is, the lower the depth and width of the heat affected zone become and becomes wider. The larger the friction coefficient, the larger the heat affected zone.