Part I—Theoretical Model for a Synchronous Thermal Instability Operating in Overhung Rotors

Abstract

Atheoretical model has been developed for a synchronousthermal instability that is caused by differential viscousshearing in bearings of overhung rotors. This model employsan unbalance threshold criterion for instability insteadof utilizing a traditional frequency-domain stability analysis.The current model will be used to investigate several casestudies for both plain and tilting pad journal bearing rotorsin the second part of this article.