Stability Contours for a Whirling Finite Journal Bearing

Abstract

The equations of motion have been solved for a journal bearing for L/D = 1/8, 1/2, 1.0, and 12.0. Trajectories have been obtained for motion of the bearing center in both uncavitated and cavitated conditions and the effect of out of balance and of friction in specific cases has been examined. From the trajectories calculated, whirl stability boundaries have been produced. The boundaries are in general accord with work by other authors. It is found that when out-of-balance load is added it sometimes makes the bearing more stable and sometimes less stable. When friction is included it always improves stability. Experimental work with no out-of-balance shows approximate agreement with theory.