Noise-related roughness on tread braked railway wheels-experimental measurements and numerical simulations

Block braking is studied experimentally and numerically with focus on the thermal phenomena, in particular on the development of localised temperature peaks: hot spots. Full-scale braking tests on an inertia dynamometer have been carried out. Block braking has also been simulated with two different FE-models, both being 2D-models, where one is based on time-averaging of the heat input to the wheel and, the other, on taking into account the transient behaviour of the heat input. The time-averaging model can predict the tendency of hot spot development quite well for cast iron and composition blocks but less well for sinter blocks. The transient model can, for the time being, only simulate short brakings.