Date
09 May 1984, 1:00 pm - 2:00 pm
Abstract
A two-pole turbogenerator posed problem of resonance and excessive vibrations at the operating speed during test runs in the Test-bed. The entire system comprising the foundation, pedestals supporting the generator, journal bearing seats, bearing oil-film, and the rotor has been modeled and analysed for computing the rotor's critical speeds as also the foundation's natural frequencies. Some of the system's parameters have been derived from actual tests. Sensitivity analysis for the rotor's critical speed that coincided with the operating speed of machine showed that this critical speed is relatively insensitive to the foundation mass as well as stiffness, and largely depends upon the stiffness characteristics of the journal bearings. The remedy to avoid excessive vibrations at operating speed has been thus found to lie in improving the journal bearings and their seatings.
Department(s)
Civil, Architectural and Environmental Engineering
Meeting Name
1st Conference of the International Conference on Case Histories in Geotechnical Engineering
Publisher
University of Missouri--Rolla
Document Version
Final Version
Rights
© 1984 University of Missouri--Rolla, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Document Type
Article - Conference proceedings
File Type
text
Language
English
Recommended Citation
Kumar, Krishen and Prakash, Shamsher, "Foundation-Bearing-Rotor Interaction Problem in Controlling Vibrations in a 120 Mw Turbo Generator" (1984). International Conference on Case Histories in Geotechnical Engineering. 5.
https://scholarsmine.mst.edu/icchge/1icchge/1icchge-theme6/5
Foundation-Bearing-Rotor Interaction Problem in Controlling Vibrations in a 120 Mw Turbo Generator
A two-pole turbogenerator posed problem of resonance and excessive vibrations at the operating speed during test runs in the Test-bed. The entire system comprising the foundation, pedestals supporting the generator, journal bearing seats, bearing oil-film, and the rotor has been modeled and analysed for computing the rotor's critical speeds as also the foundation's natural frequencies. Some of the system's parameters have been derived from actual tests. Sensitivity analysis for the rotor's critical speed that coincided with the operating speed of machine showed that this critical speed is relatively insensitive to the foundation mass as well as stiffness, and largely depends upon the stiffness characteristics of the journal bearings. The remedy to avoid excessive vibrations at operating speed has been thus found to lie in improving the journal bearings and their seatings.
