An optimal tangential contact model for wheel-rail non-Hertzian contact analysis and its application in railway vehicle dynamics simulation

Abstract

Relative to the Hertzian theory, the non-Hertzian contact model (NHM) can better reflect the contact characteristic between wheel and rail in railway vehicle dynamics simulation. In this paper, an optimal wheel-rail tangential contact model is determined for vehicle dynamics simulation. First, based on i) the modified Kik–Piotrowski (MKP) contact model, ii) four different ellipse-equivalent methods, and iii) the modified FASTSIM model or modified FaStrip model, eight NHMs are proposed. Then, taking the Kalker's variational method (KVM) as a reference, the computational accuracies of the eight NHMs for calculating the linear creep coefficient and the tangential forces for the typical tangential contact scenarios are compared. NHM II, that is, the model coupled with the MKP model, the ellipse-equivalent method adopted in the Kik–Piotrowski (KP) model, and the modified FaStrip model, shows the best computational accuracy. Finally, the traditional Hertzian & FASTSIM model, the NHM II model, and KVM model are applied to the vehicle-track coupled dynamics simulations, and the dynamics response of a high-speed train running on a slab track is calculated by different contact models. The comparison results show that the NHM II model exhibits better agreement with the KVM compared with the Hertz & FASTSIM model.