elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Impressum | Datenschutz | Kontakt | English
Schriftgröße: [-] Text [+]

Measurement of FRFs and Modal Identification In Case of Correlated Multi-Point Excitation

Füllekrug, Ulrich und Böswald, Marc und Göge, Dennis und Govers, Yves (2007) Measurement of FRFs and Modal Identification In Case of Correlated Multi-Point Excitation. In: Proceedings of the International Conference on Engineering Dynamics (ICED) 2007 (Paper ). ICED 2007 - International Conference on Engineering Dynamics, 2007-04-16 - 2007-04-18, Carvoeiro, Portugal (Europe).

[img]
Vorschau
PDF
318kB

Kurzfassung

The modal identification of large and dynamically complex structures often requires a multi-point excitation. Sine sweep excitation runs are applied when it is necessary to concentrate more energy on each line of the frequency spectrum. The conventional estimation of FRFs from multi-point excitation requires uncorrelated excitation signals. In case of multi-point (correlated) sine sweep excitation, several sweep runs with altered excitation force patterns have to be performed to estimate the FRFs. An alternative way, which offers several advantages, is to process each sine sweep run separately. The paper first describes the conventional method for FRF estimation in case of multi-point excitation, followed by two alternative methods applicable in case of correlated excitation signals. Both methods generate a virtual single-point excitation from a single run with multi-point excitation. In the first method, an arbitrary structural point is defined as a virtual driving point. This approach requires a correction of the modal masses obtained from modal analysis. The second method utilizes the equality of complex power to generate virtual FRFs along with a single virtual driving point. The computation of FRFs and the modal identification using virtual single-point excitation are explained. It is shown that the correct set of modal parameters can be identified. The application of the methods is elucidated by an illustrative analytical example. It could be shown that the separate evaluation of symmetric and anti-symmetric multi-point excitation runs yield obviously better and more reliable results compared to the conventional method. In addition, the modal analysis of the separate symmetric and anti-symmetric excitation runs is easier, since the stabilization diagrams are easier to interpret. The described methods were successfully applied during the Ground Vibration Tests on Airbus A380 and delivered excellent results. The methods are highly advantageous and may thus be established as a new standard procedure for testing aerospace structures.

elib-URL des Eintrags:https://elib.dlr.de/50077/
Dokumentart:Konferenzbeitrag (Vortrag, Paper)
Titel:Measurement of FRFs and Modal Identification In Case of Correlated Multi-Point Excitation
Autoren:
AutorenInstitution oder E-Mail-AdresseAutoren-ORCID-iDORCID Put Code
Füllekrug, UlrichNICHT SPEZIFIZIERTNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Böswald, MarcNICHT SPEZIFIZIERTNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Göge, DennisNICHT SPEZIFIZIERTNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Govers, YvesNICHT SPEZIFIZIERTNICHT SPEZIFIZIERTNICHT SPEZIFIZIERT
Datum:2007
Erschienen in:Proceedings of the International Conference on Engineering Dynamics (ICED) 2007
Open Access:Ja
Gold Open Access:Nein
In SCOPUS:Nein
In ISI Web of Science:Nein
Status:veröffentlicht
Stichwörter:structural dynamics, experimental modal analysis, multi-point sine sweep excitation, measurement of FRF, identification of modal masses.
Veranstaltungstitel:ICED 2007 - International Conference on Engineering Dynamics
Veranstaltungsort:Carvoeiro, Portugal (Europe)
Veranstaltungsart:internationale Konferenz
Veranstaltungsbeginn:16 April 2007
Veranstaltungsende:18 April 2007
Veranstalter :IDMEC/Instituto Superior Técnico
HGF - Forschungsbereich:Luftfahrt, Raumfahrt und Verkehr
HGF - Programm:Luftfahrt
HGF - Programmthema:Starrflügler (alt)
DLR - Schwerpunkt:Luftfahrt
DLR - Forschungsgebiet:L AR - Starrflüglerforschung
DLR - Teilgebiet (Projekt, Vorhaben):L - Flexibles Flugzeug (alt)
Standort: Göttingen
Institute & Einrichtungen:Institut für Aeroelastik
Hinterlegt von: Erdmann, Daniela
Hinterlegt am:31 Jul 2007
Letzte Änderung:24 Apr 2024 19:12

Nur für Mitarbeiter des Archivs: Kontrollseite des Eintrags

Blättern
Suchen
Hilfe & Kontakt
Informationen
electronic library verwendet EPrints 3.3.12
Gestaltung Webseite und Datenbank: Copyright © Deutsches Zentrum für Luft- und Raumfahrt (DLR). Alle Rechte vorbehalten.