Numerical simulation of the local film thickening in EHL

A complete solution for point contact thermal EHL with slide/roll ratios larger than 2 has been performed to simulate the dimple phenomenon (local film thickening) reported by Kaneta et al in measuring the films thicknesses profile between a glass disk and a steel ball running in the opposite direction. Results obtained from glass-steel conjunctions under different operating conditions prove that the thermal effect is the most important factor being responsible for the abnormality appearing in EHL. Numerical results reveal that a dimple occurs when the glass disk is faster than the steel ball, and disappears when the former is slower, which has been observed in the experiment by Kaneta et al. It showed that the pressure viscosity coefficient has a strong effect on the occurrence of the dimple. Also, the effects of loads on the dimple are presented.