Identification of mistuning characteristics of bladed disks from free response data-Part II

Marc Mignolet, Jason P. Delor, Alejandro Rivas-Guerra

Research output: Chapter in Book/Report/Conference proceedingConference contribution

4 Citations (Scopus)

Abstract

The focus of the present investigation is on the estimation of the dynamic properties, i.e. masses, stiffnesses, natural frequencies, mode shapes and their statistical distributions, of nabomachine blades to be used in the accurate prediction of the forced response of mistimed bladed disks. As input to this process, it is assumed that the lowest natural frequencies of the blades alone have been experitneatally measured, for example in a broach block test. Since the number of measurements is always less than the number of unknowns, this problem is indeterminate in nature. Three distinct approaches will be investigated to resolve the shortfall of data. The first one relies on the imposition of as many constraints as needed to insure a unique solution to this identification problem. Specifically, the mode shapes and modal masses of the blades are set to their design/timed counterparts while the modal stiffnesses are varied from blade-to-blade to match the measured natural frequencies. The second approach, based on the maximum likelihood principle, yields estimates of all the structural parameters of the blades through the minimization of a specified "cost function". Finally, the third approach provides a bridge between the first two methods being based on the second but yielding a mistuning model similar to that of the rust approach. The accuracy of these three techniques in predicting the forced response of mistimed bladed disks will be assessed on simple dynamic models of the blades.

Original languageEnglish (US)
Title of host publicationProceedings of the ASME Turbo Expo
PublisherAmerican Society of Mechanical Engineers (ASME)
Volume4
ISBN (Print)9780791878613
DOIs
StatePublished - 1999
EventASME 1999 International Gas Turbine and Aeroengine Congress and Exhibition, GT 1999 - Indianapolis, United States
Duration: Jun 7 1999Jun 10 1999

Other

OtherASME 1999 International Gas Turbine and Aeroengine Congress and Exhibition, GT 1999
CountryUnited States
CityIndianapolis
Period6/7/996/10/99

Fingerprint

Natural frequencies
Broaches
Stiffness
Cost functions
Maximum likelihood
Dynamic models

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Mignolet, M., Delor, J. P., & Rivas-Guerra, A. (1999). Identification of mistuning characteristics of bladed disks from free response data-Part II. In Proceedings of the ASME Turbo Expo (Vol. 4). American Society of Mechanical Engineers (ASME). https://doi.org/10.1115/99-GT-382

Identification of mistuning characteristics of bladed disks from free response data-Part II. / Mignolet, Marc; Delor, Jason P.; Rivas-Guerra, Alejandro.

Proceedings of the ASME Turbo Expo. Vol. 4 American Society of Mechanical Engineers (ASME), 1999.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Mignolet, M, Delor, JP & Rivas-Guerra, A 1999, Identification of mistuning characteristics of bladed disks from free response data-Part II. in Proceedings of the ASME Turbo Expo. vol. 4, American Society of Mechanical Engineers (ASME), ASME 1999 International Gas Turbine and Aeroengine Congress and Exhibition, GT 1999, Indianapolis, United States, 6/7/99. https://doi.org/10.1115/99-GT-382
Mignolet M, Delor JP, Rivas-Guerra A. Identification of mistuning characteristics of bladed disks from free response data-Part II. In Proceedings of the ASME Turbo Expo. Vol. 4. American Society of Mechanical Engineers (ASME). 1999 https://doi.org/10.1115/99-GT-382
Mignolet, Marc ; Delor, Jason P. ; Rivas-Guerra, Alejandro. / Identification of mistuning characteristics of bladed disks from free response data-Part II. Proceedings of the ASME Turbo Expo. Vol. 4 American Society of Mechanical Engineers (ASME), 1999.
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