Assessment of Simplified Models of Conformal Wheel-Rail Rolling Contact

Non-conformal contact models may be inadequate for solving conformal contact problems because the assumption of the flatness of the contact patch is violated in the context of conformal contacts. Although the finite element method and boundary element method with proper modifications can be used to solve conformal contact problems, their computational efficiency limits their application. To strike a balance between efficiency and accuracy, simplified conformal contact models are preferred options. Three simplified conformal contact models have been implemented based on the modified version of the Kik-Piotrowski model, INFCON model combined with FASTSIM, and FaStrip. These models are assessed through the comparisons with results from a detailed model in terms of the contact size, shape, normal pressure, tangential stress, resultant forces, and computational efficiency. The comparative analysis of two case studies shows that the non-conformal contact model produces considerable differences from the conformal models. Among the evaluated models, the adapted Kik-Piotrowski combined with FASTSIM is the fastest, while under certain conditions its accuracy is lower than the modified INFCON + FASTSIM/FaStrip models which show overall better agreement with the reference.