An improved finite element model for three-dimensional wheel–rail rolling contact

Abstract

A three-dimensional wheel–rail rolling contact model (3D WRRCM) developed using the explicit finite element method (FEM) can be used to analyze the dynamic performances of wheelsets and tracks while considering the wheelset rotation and translation, as well as the real wheel–rail contact mechanism. When using the FEM with static initialisation (traditional model), the first step is to calculate the static wheel–rail displacement, strain, and stress when applying axle loading on the wheel and neglecting the wheelset rotation and translation. Then, using these results as the initial conditions, the dynamic wheel–rail displacement, strain, and stress are calculated while considering the wheelset rotation and translation by adopting the explicit dynamic solution method. However, obtaining a solution using this traditional method is time consuming, and the solution can be divergent because of the impulse produced by the suddenly increasing wheelset rotation when proceeding from the initial condition to the dynamic. The optimised method developed in this study can solve this problem. A comparison of the results from the traditional and optimised methods reveals that in the optimised method, the softer initial impulse effectively shortens the track length needed for the calculation and improves the solution efficiency.