Stability of a Squeeze-Film Journal Bearing

Abstract

An investigation is made of the regions of stability for a compressible fluid, squeeze-film journal bearing of infinite length. Motion along one axis considered and the resulting dynamic equation is solved two ways: by variational techniques and by numerical techniques. The solution from the variational analysis can be approximated by a Mathieu equation thus showing that instability can occur at one-half the driving frequency. The numerical analysis shows the stability limits in terms of the load, drive amplitude, and dimensionless “mass.” The stability analysis is significant as there appears to be a rather large number of combinations of the parameters for which the squeeze-film journal is not stable. The stability characteristics of a squeeze-film bearing should, therefore, be examined carefully before application.