A Numerical Model for the Elastic Frictionless Contact of Real Rough Surfaces

TLDR

The study presents a computer model for dry, frictionless contact of real rough surfaces that relaxes traditional roughness assumptions. The model employs stylus‑recorded surface data, reproduces smooth‑case results accurately, analyzes contact pressure and displacements on a bearing surface with a debris‑induced dent, studies load–real contact area relationships for various profiles, and compares outcomes with random process theory. The model accurately reproduces smooth‑case results, demonstrates its applicability to bearing‑surface pressure analysis and load–contact area studies, and offers insight into early life failure caused by debris‑contaminated oil.

Abstract

A computer model for the dry, frictionless contact of real rough surfaces is presented. The model uses data directly recorded from a stylus measuring instrument and as a confirmation of the model it is shown to reproduce “smooth case” results with a high level of accuracy. Results are given for two important applications of the technique. The first considers the analysis of the contact pressure and displacements for a bearing surface including a debris induced dent in the contact zone. The results go someway to providing an explanation of early life failure often associated with debris contaminated oil. Secondly the relationship between load and real contact area is studied for a sample set of surface profiles. The results obtained are compared with random process theory. It is proposed that the numerical model represents a different approach to rough surface contact allowing certain assumptions about the nature of surface roughness to be relaxed.