Abstract This paper presents a rigid contact approach to analyse the two-point wheel-rail contact scenario using the simplified constraint-based contact method called Knife-edge Equivalent Contact method (KEC-method). The proposed approach makes use of the computationally efficient online solution of the KEC constraints, where a single-point rail is in contact with an equivalent wheel profile, and provides an exact relation between the location of the contact points in the equivalent and real profiles. In this context, the two-point contact scenario can be easily dealt by linearly softening the KEC-constraints in the vicinity of the two-point contact, that gives a continuous and unique contact point solution between each wheel-rail pair and avoids finite contact point jumps between tread and flange. This allows an efficient kinematic solution of the two-point contact scenario. However, to properly account for a dynamic equivalence of the two-point contact scenario in the computation of the tangential contact forces, the reaction force acting on the wheel when the contact point lies on the tread-flange transition, is transformed into two contact forces acting on the tread and flange respectively maintaining the resultant equilibrium of forces at the wheel.

中文翻译：

---

使用刀刃等效接触约束法分析两点轮轨接触场景

摘要 本文提出了一种刚性接触方法，使用称为刀刃等效接触方法（KEC 方法）的简化的基于约束的接触方法来分析两点轮轨接触场景。所提出的方法利用 KEC 约束的计算效率在线解决方案，其中单点轨道与等效车轮轮廓接触，并提供等效轮廓和实际轮廓中接触点位置之间的精确关系。在这种情况下，可以通过线性软化两点接触附近的 KEC 约束来轻松处理两点接触场景，从而在每个轮轨对之间提供连续且唯一的接触点解决方案并避免有限接触点在胎面和法兰之间跳跃。这允许两点接触场景的有效运动学解决方案。然而，为了在计算切向接触力时正确考虑两点接触情况的动态等效性，当接触点位于胎面法兰过渡处时作用在车轮上的反作用力被转换为两个接触力分别作用在胎面和法兰上，保持车轮上的合力平衡。