We present a novel approach for the simulation of dynamic friction in engineering systems, based on a new surface asperity model including creep effects. Our novel friction model aims at understanding the link between the microscopic origins of friction dynamics and the response of the engineering-level friction induced vibrations. The approach is based on the assumption that the time- and velocity-dependent friction coefficient is mainly caused by creep growth of surface asperity contacts (microscopic contact patches between two rough surfaces) as proposed by Kragelskii, Rabinowicz, Scholz and others. At the heart of our approach is a new asperity model that includes creep effects. Based on the pioneering work of Etsion et al., we conducted extensive FEM simulations to analyze the creep behavior of an elastic-perfectly plastic hemisphere in contact with a rigid flat. The new asperity model is used as a building block for a fractal model for the contact between rough surfaces. The model yields the time- and velocity-dependent macroscopic friction coefficient. We demonstrate the practical applicability of the new dynamic friction model in a simple block-on-conveyor test case to analyze friction induced vibrations.

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