This paper is concerned with the dynamic behavior of geared rotor systems supported by squeeze film dampers, wherein coupled bending torsion vibrations occur. Considering the imbalance forces and gravity, it is shown that geared rotors exhibit chaotic behavior due to nonlinearity of damper forces. The route to chaos in such systems is established. In geared rotor systems, it is shown that torsional excitation can induce lateral vibrations. It is shown that squeeze film dampers can suppress large amplitudes of whirl arising out of torsional excitation.

Issue Section:
Gas Turbines: Structures and Dynamics
Topics:
Rotors, Dampers, Excitation, Vibration, Chaos, Gravity (Force), Torsion, Whirls
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