Wear simulation in lubricated contacts considering wear-dependent surface topography changes

Abstract

Along with friction, wear in lubricated contacts is one of the most essential design criteria. The use of low-viscosity lubricants, as well as changing operating conditions, may lead to the wear-causing operating condition of mixed friction. For wear assessment, in the last decades numerical simulations have been confirmed as a powerful tool. The level of detail of the simulation model has a significant influence on the simulation results. The local wear heights for a hydrodynamic journal bearing under constant operating conditions are calculated numerically. A variant study is used to determine the influence of elastic deformation, cavitation model and the consideration of the wear-dependent surface topography. The surface topography, which is subject to change especially during running-in, is taken into account in the form of wear-dependent asperity contact pressure curves, respectively wear-dependent flow factors. To validate the simulation results, tests were carried out on a rotational tribometer. The results show that the consideration of the wear-dependent surface topography has a significant influence on the wear development and thus the trend evaluated from the experiment can be better assessed.