A Computer Program Package for the Prediction of EHL and Mixed Lubrication Characteristics, Friction, Subsurface Stresses and Flash Temperatures Based on Measured 3-D Surface Roughness

Abstract

A complete computer program package has been developed in the present work based on a recently developed unified numerical approach for point contact problems. This approach is capable of simulating the entire transition from the full film EHD, mixed, down to boundary lubrication, using measured 3-D roughness. The numerical solution can cover a full range of λ ratio, from infinity down to zero. Based on the calculated film thickness (or gap) and pressure distribution in the contact, subsurface stresses can readily be predicted. Also, friction and flask temperatures can be computed by using a non-Newtonian fluid model in the hydrodynamic regions and a measured (or assumed) coefficient of friction for boundary lubrication in the contact regions. Sample cases show that this computer program package is robust with no convergence problems encountered even under severe operating conditions. It appears to be a useful engineering tool for industrial applications.

KEY WORDS:

• Elastohydrodynamic Lubrication
• Boundary Lubrication
• Surface Roughness