DEBRIS DENTING EFFECTS ON ELASTOHYDRODYNAMIC LUBRICATED CONTACTS

A finite element model was developed to investigate the effects of a s pherical debris on elastohydrodynamically lubricated rolling/sliding c ontacts. Three dimensional dent profiles were obtained using finite el ement method showing horseshoe shape material pile-up along the rollin g direction. The dent profiles obtained from the finite element analys is (FEA) were compared with the experimental results. There is good qu alitative agreement between FEA and experimental dent profiles. The FE A dent profiles were then used in a time dependent thermal elastohydro dynamic lubrication (EHL) point contact model to analyze the dent effe cts on the pressure, film thickness and temperature profiles. The pres ence of a dent in lubricated contacts generates high pressure spikes a nd increases the peak temperature. The internal stresses were calculat ed based on the pressure and traction data obtained from the EHL analy sis. The results indicate that a dent created by a debris will cause t he internal maximum Von Mises stress to occur near the surface, which contributes to surface initiated failures.