The modelling of the wheel–rail contact is fundamental in the railway field since the contact forces directly affect vehicle dynamics, wear, safety and maintenance. In this context, the development of a realistic adhesion model able to describe degraded adhesion conditions is still an open problem because of the complex non-linear behaviour of the adhesion coefficient. To face this problem, in this work an innovative degraded adhesion model has been developed taking into account important phenomena like large sliding at the contact interface, the consequent energy dissipation and the adhesion recovery caused by the cleaning effect on the rail due to the friction forces. The new approach, based on FASTSIM algorithm and Polach theory, is numerically very efficient and has been specifically designed for multibody applications. The developed model has been validated through the comparison with experimental data related to suitable braking manoeuvres.

轮轨接触建模是铁路领域的基础，因为接触力直接影响车辆动力学、磨损、安全和维护。在这种情况下，由于粘附系数的复杂非线性行为，开发能够描述退化粘附条件的真实粘附模型仍然是一个悬而未决的问题。为了解决这个问题，在这项工作中，我们开发了一种创新的退化粘附模型，其中考虑到了一些重要现象，例如接触界面处的大滑动、随之而来的能量耗散以及由于摩擦力对钢轨的清洁作用引起的粘附恢复. 这种基于 FASTSIM 算法和 Polach 理论的新方法在数值上非常有效，并且专为多体应用而设计。