Characteristics of a magnetically levitated flexible rotor when in contact with one or more auxiliary bearings

P. S. Keogh, Y. H. Seow, M. O. T. Cole

Research output: Chapter in Book/Report/Conference proceedingChapter

  • 2 Citations

Abstract

The case for installing auxiliary bearings in parallel with magnetic bearings is often made with regard to touchdown, when a complete system failure occurs. The work reported in this paper focuses on the case when rotor/auxiliary bearing contact occurs, but the magnetic bearings retain their functionality. One may envisage future transportation applications in which this situation would occur, for example, during high acceleration levels induced by turbulence. An understanding of the rotor dynamic response during contact conditions could enable auxiliary bearing life expectancy to be extended using appropriate control action from the still functional magnetic bearings. To achieve this, a system model is required for control strategy design purposes. This paper considers the development of a non-linear system model for predicting the contact dynamics in a flexible rotor/magnetic/auxiliary bearing system. Previous experimental work produced similar contact dynamic response characteristics; whether due to unbalance or circular forcing through a magnetic bearing. Initial model-based predictions of these tests did not provide sufficiently accurate reproduction of the measured orbits, particularly in the presence of auxiliary bearing misalignment and multi-plane rotor contact. Parameter variations are thus undertaken to investigate the reasons for these differences. Contrary to expectations, uncertainty in the magnetic bearing characteristics during contact conditions appears to offer an explanation.
LanguageEnglish
Title of host publicationProceedings of the ASME Turbo Expo, 2005
Subtitle of host publicationVolume 4
Place of PublicationNew York, U. S. A.
PublisherASME
Pages791-799
ISBN (Print)0791847276
StatusPublished - 2005
EventASME Turbo Expo, 2005 - Nevada, USA United States
Duration: 6 Jun 20059 Jun 2005

Conference

ConferenceASME Turbo Expo, 2005
CountryUSA United States
CityNevada
Period6/06/059/06/05

Fingerprint

Bearings (structural)
Magnetic bearings
Rotors
Dynamic response
Nonlinear systems
Orbits
Turbulence

Cite this

Keogh, P. S., Seow, Y. H., & Cole, M. O. T. (2005). Characteristics of a magnetically levitated flexible rotor when in contact with one or more auxiliary bearings. In Proceedings of the ASME Turbo Expo, 2005: Volume 4 (pp. 791-799). New York, U. S. A.: ASME.

Characteristics of a magnetically levitated flexible rotor when in contact with one or more auxiliary bearings. / Keogh, P. S.; Seow, Y. H.; Cole, M. O. T.

Proceedings of the ASME Turbo Expo, 2005: Volume 4. New York, U. S. A. : ASME, 2005. p. 791-799.

Research output: Chapter in Book/Report/Conference proceedingChapter

Keogh, PS, Seow, YH & Cole, MOT 2005, Characteristics of a magnetically levitated flexible rotor when in contact with one or more auxiliary bearings. in Proceedings of the ASME Turbo Expo, 2005: Volume 4. ASME, New York, U. S. A., pp. 791-799, ASME Turbo Expo, 2005, Nevada, USA United States, 6/06/05.
Keogh PS, Seow YH, Cole MOT. Characteristics of a magnetically levitated flexible rotor when in contact with one or more auxiliary bearings. In Proceedings of the ASME Turbo Expo, 2005: Volume 4. New York, U. S. A.: ASME. 2005. p. 791-799.
Keogh, P. S. ; Seow, Y. H. ; Cole, M. O. T./ Characteristics of a magnetically levitated flexible rotor when in contact with one or more auxiliary bearings. Proceedings of the ASME Turbo Expo, 2005: Volume 4. New York, U. S. A. : ASME, 2005. pp. 791-799
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