EHD modeling of angular contact ball element bearings

Abstract

The objective of this work is the study of the dynamic of angular contact ball element bearings considering the elastohydrodynamic lubrication. A computational model was built to foresee the dynamic behavior influence on the lubrication condition of those components. The model of EHD lubrication is taken into account in the bearing dynamic model, to obtain coefficients of stiffness, damping and subsequent characterization of the bearing, for different loading condition. The dynamic model has five degrees of freedom. The model considers, in its development, centripetal force and gyroscopic effects, and static equilibrium analysis are accomplished to find the force distribution in each sphere. With the force distribution, the dimensionless Moes parameters of lubrication and load are calculated, as well as the contact elliptic ratio, which are used in the EHD model. Therefore, it is possible to calculate the contact pressure, film thickness, as well as the contact force parameters and corresponding stiffness and damping coefficients.