Non-Newtonian Starved Thermal-Elastohydrodynamic Lubrication of Finite Line Contacts

Abstract

Heavily loaded finite line contacts working under elastohydrodynamic lubrication (EHL) conditions are quite often found in machine elements. However, a perfect line contact requires absolute alignment of the axes of the contacting bodies, which is difficult to achieve. In order to overcome this problem and avoid edge loading, one or both of the contacting cylinders are crowned. This article presents a new model for finite length line contacts. In addition to the finite length of the contact and the profile of the contact bodies, the proposed model takes into account the thermal effects, non-Newtonian lubricant behavior, and starved lubrication. The governing equations are solved using the multilevel multigrid technique. The results were validated by comparing film shape and pressure distribution of a finite line contact against an infinite one. The influence of the lubricant starvation and fillet radius on the pressure distribution, film shape, temperature distribution, and friction coefficient are presented. Finally, the effect of alternative roller profiles is shown.