Development of a new procedure for the wheel-rail contact force evaluation in simulations of railway dynamics

The numerical solution of the dynamics of a railway vehicle interacting with supporting structures is facilitated by mathematical models and evaluation techniques. In fact, the vehicle multibody modelling, the supporting structure models, and the Hertz and Kalker theories concerning the wheel-rail contact forces are indispensable guides to the dynamic analysis of railway systems. The present work is concerned with an evaluation method for the normal direction contact force component at the point of contact between the rail and wheel profiles. It proposes an alternative approach, which eliminates the typical problems of the Hertz formulation. The evaluation method developed ignores the contact stiffness and is based on the elastic deformation of the supporting structure, which, as the simulations demonstrate, leads to physically more acceptable results and shorter calculation times.