Stability analysis of a flexible rotor supported on finite hydrodynamic porous journal bearing using a non-linear transient method

Abstract

A theoretical analysis has been carried out to study the stability of a flexible rotor supported on two symmetrical finite porous oil journal bearings at the two ends. The rotor is modelled by Timoshenko beam theory. An investigation of stability has been carried out using a non-linear transient method. This analysis enables to trace the journal centre locus at different locations of the rotor, however, only the bearing location rotor centre trajectories are taken up in this work and subsynchronous critical parameters are estimated. Several trajectories of the journal centre have been obtained for different operating conditions. The stability curves have been drawn for different eccentricity ratios. This work has been carried out in non-dimensional form and the effects of bearing feeding parameter, slenderness ratio, and material properties of the beam on stability are investigated.

Keywords

Timoshenko beam porous bearing stability non-linear analysis flexible rotor

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