Abstract

An improved transfer matrix method is developed to analyze nonlinear rotor-bearing systems. The rotating shaft is described by the Timoshenko beam theory which considers the effect of the rotary inertia and shear deformation. A typical roller bearing model is assumed which has cubic nonlinear spring and linear damping characteristics. Transfer matrices for the Timoshenko shaft element, disk element, and nonlinear bearing element are derived and the global transfer matrix is formed. The steady-state response of synchronous, subharmonic, and superharmonic whirls is determined using the harmonic balance method. Two numerical examples are presented to demonstrate the effectiveness of this approach.

Issue Section:
Gas Turbines: Structures and Dynamics
Keywords:
rotors, machine bearings, nonlinear systems, continuum mechanics, transfer function matrices, vibrations, harmonics
Topics:
Bearings, Rotors, Steady state, Disks
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Copyright © 2002
 by ASME
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