Stability characteristics and CFD analysis of two-phase flow of oil film journal bearing having two oil filler holes

Abstract

In this paper, a new stabilization method which can control an oil whip utilizing the starved lubrication on small bore journal bearing is described. Oil whip is one of the excited vibration that is caused by the action of oil film force of journal bearing. Therefore, it is very important to suppress the oil whip in the bearing design. Under the background the effects of two oil filler holes and these oil supply angles on journal bearing characteristics are tested, because it is considered that the critical flow rate in starved lubrication of bearings having two oil filler holes increases compared to bearing having one oil filler hole. Moreover, the difference in pressure distributions is confirmed by CFD (Computational Fluid Dynamic) analysis. As result, the critical flow rates for stabilization of the two oil filler hole bearing larger than that of one oil filler hole one. Moreover the temperature rise and the film thickness in starved lubrication have been changed by changing the conditions of the oil filler holes. Consequently, the problems of the oil temperature and the oil film thickness on stabilization method using the starved lubrication is considered to be solved by the proposed two oil filler holes method.