A fast version of ‘CONTACT’ for normal problem calculations

Abstract

In its different versions, the CONTACT method developed by Prof. Kalker is the primary reference in wheel-rail contact mechanics. Despite adopting simplifications associated with the elastic behaviour of the solids and being a non-conformal contact theory, CONTACT provides precise solutions for most wheel-rail contact conditions, with lower computational and modelling costs than other numerical methods such as Finite Elements. Nevertheless, the computational cost of CONTACT is still too high for its implementation in dynamic simulation.The present work proposes a fast and accurate wheel-rail contact method for normal problems based on Kalker's CONTACT algorithm. Dissimilarly to CONTACT, the new method formulates the normal traction distribution through a suitable basis, which reduces the dimension of the problem. This method is able to faithfully reproduce the contact patch and the normal traction distribution, even when the yaw angle of the wheelset is non-zero. Results obtained with this method are compared with the ones calculated with CONTACT, and errors about 0.05% are obtained in normal contact forces, with a reduction on the computation cost between 30 and 60 times.