Resistive field bond graph models for hydrodynamically lubricated bearings

Abstract

AbstractA lumped parameter model was developed for hydrodynamically lubricated bearings: elements that feature fully lubricated contact between surfaces in relative motion. The bearing models were represented as bond graphs. Currently, bond graphers view bearings as single-port resistance elements, which only account for losses associated with relative tangential motions between surfaces. Machine designers view bearings as devices that generate forces normal to surfaces in relative motion, to maintain position and alignment of shafts or surfaces. Both effects occur in real bearings, coupled together via physics. A lumped parameter model for hydrodynamically lubricated bearings is developed in this paper. The model includes the physical coupling between rotational degrees of freedom and orthogonal degrees of freedom associated with maintaining alignments. These lumped parameter models were synthesized from solutions of the Reynolds equation for various bearing geometries, and include normal motion and sque...