Stability Threshold of Flexibly Supported Hybrid Gas Journal Bearings

Abstract

Results of experimental investigations of the dynamic properties of elastic supports for gas bearings having the form of rubber O-rings are presented. Theoretical calculations of the stability threshold of an externally pressurized gas bearing system elastically supported by means of O-rings were performed. An experimental investigation of the stability threshold of this gas bearing system was made. Comparisons between theoretical and experimental results verify the theoretical model and illustrate the possibility of its application to design purposes.

Pressure and Squeeze Effects on the Dynamic Characteristics of Elastomer O-Rings Under Small Reciprocating Motion

“…various elastomer springs and dampers this is not the case for O-rings. References [2] and [3] present results on measured dynamic properties of elastomer O-rings under reciprocating unidirctional radial squeeze, similar to the mode of application in squeeze film dampers. In references [4] and [5] axial forces transmitted by O-rings subjected to a reciprocating drag were measured for various amplitudes and frequencies.…”

Dynamic Characterization of Rubber O-Rings: Squeeze and Size Effects

“…The first experimental work in which the half-speed whirl was avoided by mounting the bushes flexibly goes back 50 years [1]. O-rings were used in gas bearings to improve the static stiffness [2], but in most cases their main function is to overcome the whirl instability in journal bearings [3,4] or the pneumatic hammer [5]. In [6,7] an analytical model is developed to predict the restoring and hysteresis characteristics of elastomer O-rings mounted in squeeze film dampers.…”

Effect of Dynamic Properties of Support O-Rings on Stability of Herringbone-Grooved Aerodynamic Journal Bearings

“…In the literature, it was qualitatively shown that the flexible support of the bearing sleeve could raise the threshold speed at which the loss of stability occurs. Powell et al [3] and Kazimierski et al [4] discussed the stability of an externally pressurized gas bearing sustained by rubber O-rings and concluded that the use of the O-rings lead to a higher whirl onset speed. In such bearing system, a bearing sleeve was allowed to move to follow a rotating shaft.…”