The Influence of the Elliptic Ratio on Elastohydrodynamically Lubricated Point Contacts

Every year, the market expects greater quality and reliability not only from the newly released products, but also from common daily use goods. In this case, even a simple part, as a rolling element bearing, can be the root cause for a “product failure”. Unusual noise and vibrations are common issues for costumers, who in that case normally avoid using the vehicles. In rolling element bearings, most of the failures that produce noise and vibrations, are related to the contact stress and fatigue of raceways and rolling elements. Thus, it is essential to understand the contact mechanisms and, therefore, the lubrication conditions of these systems. In this work, the Elastohydrodynamic (EHD) lubricated point contacts are studied. The most important goal is to understand the influence of the elliptic ratio on the oil film and the contact pressure. The governing equations will be analyzed, regarding the behavior of the Reynolds equation and the elastic equation, under influence of the contact's elliptic ratio. Two different dimensionless numerical models are discussed and further applied to a Multi-Level finite difference method. The numerical method is validated with a number of general contact examples provided in the literature. After that, a real EHD contact case is simulated based on the highly loaded element of a deep groove ball bearing.