2-DIMENSIONAL RANDOM SURFACE MODEL FOR ASPERITY CONTACT IN ELASTOHYDRODYNAMIC LUBRICATION

Relations for the asperity contact time fraction during elastohydrodynamic lubrication of a ball bearing are presented. The analysis is based on a two-dimensional random surface model and actual profile traces of the bearing surfaces are used as statistical sample records. The results of the analysis show that transition from 90% contact to 1% contact occurs within a dimensionless film thickness range of approximately 4-5. This thickness ratio is several times larger than that reported in the literature where onedimensional random surface models were used. It is shown that low-pass filtering of the statistical records will bring agreement between the present results and those in the literature. © 1979.