The Effect of Viscous Shear Heating on Both Film Thickness and Rolling Traction in an EHL Line Contact—Part I: Fully Flooded Conditions

A theoretical analysis of both fully flooded rolling traction and film thickness in an EHL line contact is described and modified formulas for fully flooded isothermal conditions are presented. These are compared with the Grubin, Dowson, and Higginson film thickness formulas, and the rolling traction theory by Archard and Baglin (1975). The effect of viscous shear heating in the inlet region has been investigated and new equations for both fully flooded film thickness and rolling traction, including this thermal effect, are introduced. These equations predict significant reductions in both film thickness and rolling traction, relative to the isothermal case, as speed is increased. Viscous shear heating effect is found to be negligible only at very low rolling speeds. The results of the theoretical analysis compare well with experimental data presented by Dyson, Naylor, and Wilson (1966) and Adams and Hirst (1973).