Inertia effects in rheodynamic lubrication of a squeeze film bearing

Abstract

Recently, it has been emphasized that in order to analyse the performances of bearings adequately, it is necessary to take into account the combined effects of fluid inertia forces and non-newtonian characteristics of lubricants. In this research work, the effects of inertia forces in the squeeze film bearing lubricated with a Bingham fluid have been investigated. A Bingham fluid possesses a yield value, therefore the shape and extent of the core formation is determined numerically for various values of Bingham number and the flow is confined to the region between the core and the disks. Averaging the inertia terms over the film thickness and defining a modified pressure gradient, the rheodynamic lubrication equation containing the inertia terms has been analysed for velocity distributions in the two regions separating the core formation. For different values of Bingham number and squeeze Reynolds' number, the film pressure and the load capacity of the bearing have been obtained. Significant inertia effects on the load capacity of the bearing have been observed. The percentage increase in load-carrying capacity, due to inertia forces for materials with varying yield values and for different values of squeeze Reynolds' number, has been compared.