Modal parameter estimation of turbomachinery in operation taking into account friction damping

verfasst von: Mona Amer, Carlos E. Ventura, Niklas Maroldt, Joerg R. Seume, Joerg Wallaschek
Abstract: Operational modal analysis is used to identify modal parameters of a rotating machine, more specifically an axial compressor. The application of operational modal analysis to rotating machines is considered a challenge, since the rotation disturbs the output measured and can be falsely identified as structural characteristics. Thus, an effective approach to handle the rotor speed harmonics consisting of a modified technique for harmonic removal and a criterion for the identification of harmonics is presented. Additionally, the axial compressor investigated in this work is characterized by numerous joints introducing friction. Thus, localized nonlinear structural behavior needs to be taken into account, when determining the sought-after modal parameters. In order to deal with the friction influence leading to varying eigenfrequencies and damping ratios with increasing response amplitudes, an operating point dependent modal parameter identification process is proposed. The damping values, which are identified in operation, decrease by up to one order of magnitude from the modal damping in standstill condition. These results demonstrate the relevance of an operating point dependent analysis of the structural behavior of rotating machines.
Organisationseinheit(en): Institut für Turbomaschinen und Fluid-Dynamik
Institut für Dynamik und Schwingungen
Externe Organisation(en): University of British Columbia
Typ: Artikel
Journal: Mechanical Systems and Signal Processing
Band: 216
Anzahl der Seiten: 21
ISSN: 0888-3270
Publikationsdatum: 01.07.2024
Publikationsstatus: Veröffentlicht
Peer-reviewed: Ja
ASJC Scopus Sachgebiete: Steuerungs- und Systemtechnik, Signalverarbeitung, Tief- und Ingenieurbau, Luft- und Raumfahrttechnik, Maschinenbau, Angewandte Informatik
Elektronische Version(en): https://doi.org/10.1016/j.ymssp.2024.111414 (Zugang: Offen)

BibTeX

@article{f8cf455e80b44da7b545435aec326a47,
title = "Modal parameter estimation of turbomachinery in operation taking into account friction damping",
abstract = "Operational modal analysis is used to identify modal parameters of a rotating machine, more specifically an axial compressor. The application of operational modal analysis to rotating machines is considered a challenge, since the rotation disturbs the output measured and can be falsely identified as structural characteristics. Thus, an effective approach to handle the rotor speed harmonics consisting of a modified technique for harmonic removal and a criterion for the identification of harmonics is presented. Additionally, the axial compressor investigated in this work is characterized by numerous joints introducing friction. Thus, localized nonlinear structural behavior needs to be taken into account, when determining the sought-after modal parameters. In order to deal with the friction influence leading to varying eigenfrequencies and damping ratios with increasing response amplitudes, an operating point dependent modal parameter identification process is proposed. The damping values, which are identified in operation, decrease by up to one order of magnitude from the modal damping in standstill condition. These results demonstrate the relevance of an operating point dependent analysis of the structural behavior of rotating machines.",
keywords = "Axial compressor, Operational modal analysis, Rotation synchronous vibrations, Structural health monitoring, Viscous & friction damping",
author = "Mona Amer and Ventura, {Carlos E.} and Niklas Maroldt and Seume, {Joerg R.} and Joerg Wallaschek",
note = "Publisher Copyright: {\textcopyright} 2024 The Authors",
year = "2024",
month = jul,
day = "1",
doi = "10.1016/j.ymssp.2024.111414",
language = "English",
volume = "216",
journal = "Mechanical Systems and Signal Processing",
issn = "0888-3270",
publisher = "Academic Press Inc.",
}