Dynamic Loading of Micropolar Fluid Lubricated Short Journal Bearings

Abstract

Dynamically loaded bearings in which the load alternates or rotates are studied in this paper. The Reynolds equation for the general case of a dynamically loaded infinitely short bearing is derived, where the lubricant is assumed to be micropolar. Detailed consideration is given to the dynamic behaviour of squeeze films in a short journal bearing under a sinusoidal load with no journal rotation. Various bearing characteristics are calculated, assuming a full film to exist. The micropolarity of the fluid results in more resistance to journal motion, thereby allowing smaller eccentricities for a constant load. The overall conclusion of this study is an increase in the effective viscosity due to the micropolarity of the lubricant. This theory may find application in lubrication when additives are used.