Behavior of surface dent in lubricated point-contacts

The behavior of single dent in thin film thickness in concentrated contact was studied using full-scale lubrication model. Paraffinic base oil 5R600 was used as lubricant with dynamic viscosity 0.099Pa-sec and pressure viscosity coefficient 23 G/Pa at 40°C. As the dent goes through the contact, the film distribution was changed locally. As the dent approached to the center of the contact, a gradual enhancement in the film thickness was observed at the trailing edge of dent, correspondingly, the pressure rise. As the dent gradually entered the contact, the film thickness at the leading edge of the dent presented local enhancement with a little reduction downstream. The pressure increased corresponding to the film enhancement. At the trailing edge of dent, there was also a local reduction in film thickness. The simulation results were in good agreement with experiment. This is an abstract of a paper presented at the World Tribology Congress (Kyoto, Japan 9/6-11/2009).