Estimating the Severity of Shaft Vibrations Within Fluid Film Journal Bearings

Abstract

Proximity probes are being widely used in turbomachinery to measure the amplitude of shaft vibrations within fluid film bearings. There has been, however, little information available for judging the degree of severity of such vibrations. The present paper provides an analysis which correlates shaft vibration amplitude with some basic bearing parameters—allowable dynamic load on the bearing, its size, geometry, and operating conditions. Curves are provided for several bearing geometries which can be used for a rational estimate of allowable shaft vibration levels.