Abstract The wheel-rail contact modeling problem assumes a preponderant role on the dynamic analysis of railway systems using multibody systems formulations. The accurate and efficient evaluation of both location and magnitude of the wheel-rail contact forces is fundamental for the development of reliable computational tools. The wheel concave zone might be a source of numerical difficulties when searching the contact points, which has been neglected in several works. Here, it is demonstrated that the minimum distance method does not always converge when the wheel surface is not fully convex, being an alternative methodology proposed to perform the contact detection. This approach examines independently the contact between each wheel strip and the rail, where the maximum virtual penetration is determined and associated with the location of the contact point. Then, an Hertzian-based force model is considered for both normal and tangential forces. The results obtained from dynamic simulations show that the minimum distance method and the proposed methodology provide a similar response for simplified wheel profiles. However, the new approach described here is reliable in the identification of the contact point when realistic wheel profiles are considered, which is not the case with the minimum distance method.

中文翻译：

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用于改进铁路动态分析的真实轮轨表面接触检测的三维方法

摘要 轮轨接触建模问题在使用多体系统公式的铁路系统动态分析中占据主导地位。准确有效地评估轮轨接触力的位置和大小是开发可靠计算工具的基础。在搜索接触点时，轮凹区可能是数值困难的一个来源，这在一些工作中被忽略了。在这里，证明了当车轮表面不完全凸出时，最小距离方法并不总是收敛，这是建议执行接触检测的替代方法。这种方法独立检查每个轮带和轨道之间的接触，其中最大虚拟穿透被确定并与接触点的位置相关联。然后，对法向力和切向力都考虑基于赫兹的力模型。从动态模拟中获得的结果表明，最小距离方法和所提出的方法为简化的车轮轮廓提供了类似的响应。然而，当考虑现实的车轮轮廓时，这里描述的新方法在识别接触点方面是可靠的，而最小距离方法则不然。