The experimental identification of a long flexible rotor with three magnetic bearing journals is presented. Frequency response functions are measured between the magnetic bearing journals and the sensor locations while the rotor is suspended horizontally with piano wire. These frequency response functions are compared with the responses of a rotor model and a reconciliation process is used to reduce the discrepancies between the model and the measured data. In this identification, the wire and the fit of the magnetic bearing journals are identified as the sources of model error. As a result of the reconciliation process, equivalent dynamic stiffness are calculated for the piano wire and the fit of the magnetic bearing journals. Several significant numeral issues that were encountered during the process are discussed and solutions to some of these problems are presented.

Issue Section:
Gas Turbines: Structures and Dynamics
Keywords:
rotors, turbines, magnetic bearings, frequency response, dynamics, modelling, error analysis, feedback
Topics:
Frequency response, Magnetic bearings, Rotors, Transfer functions, Wire, Errors
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Copyright © 2003
 by ASME
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