Advanced processing of collocated acceleration signals in symmetric beam-like structures with applications to damage detection in a propeller

Georgiou, IT

dc.contributor.author	Georgiou, IT	en
dc.date.accessioned	2014-03-01T02:47:16Z
dc.date.available	2014-03-01T02:47:16Z
dc.date.issued	2011	en
dc.identifier.issn	1045-389X	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/33044
dc.subject	distributed sensing	en
dc.subject	modal data processing	en
dc.subject	structural dynamics	en
dc.subject	structural health monitoring	en
dc.subject.classification	Materials Science, Multidisciplinary	en
dc.subject.other	Acceleration signals	en
dc.subject.other	Beam-like structures	en
dc.subject.other	Damage index	en
dc.subject.other	Damage size	en
dc.subject.other	Dissipation factors	en
dc.subject.other	Distributed sensing	en
dc.subject.other	Energy level	en
dc.subject.other	Energy spectra	en
dc.subject.other	Modal data	en
dc.subject.other	Modal structures	en
dc.subject.other	Non-linear dynamics	en
dc.subject.other	Normal modes of vibration	en
dc.subject.other	Power law	en
dc.subject.other	Relative distances	en
dc.subject.other	Return map	en
dc.subject.other	Spatio-temporal	en
dc.subject.other	Strategic locations	en
dc.subject.other	Structural health	en
dc.subject.other	Accelerometers	en
dc.subject.other	Data handling	en
dc.subject.other	Defects	en
dc.subject.other	Dynamics	en
dc.subject.other	Flow fields	en
dc.subject.other	Modal analysis	en
dc.subject.other	Principal component analysis	en
dc.subject.other	Propellers	en
dc.subject.other	Signal detection	en
dc.subject.other	Spectroscopy	en
dc.subject.other	Structural analysis	en
dc.subject.other	Structural dynamics	en
dc.subject.other	Structural health monitoring	en
dc.subject.other	Damage detection	en
dc.title	Advanced processing of collocated acceleration signals in symmetric beam-like structures with applications to damage detection in a propeller	en
heal.type	conferenceItem	en
heal.identifier.primary	10.1177/1045389X11414088	en
heal.identifier.secondary	http://dx.doi.org/10.1177/1045389X11414088	en
heal.language	English	en
heal.publicationDate	2011	en
heal.abstract	It is found that ensembles of collocated experimental acceleration signals induced by impulses applied sequentially over the surface of beam-like structures are characterized by fast-decaying POD-modal energy spectra. Governed by a power law, this type of quite fast decay directly reflects high level of spatio-temporal coherence. Collocated ensembles of acceleration signals at various locations are governed by identical POD modes representing normal modes of vibration. Thus, collocated measurements of impulse-induced acceleration signals furnish a physics-carrying spatially distributed sensing of free dynamics. In view of this fact, three accelerometers were placed on strategic locations on an aircraft propeller to acquire collocated databases and thus we obtained an optimal reduced modal characterization of impulse-induced free dynamics. Quite interesting from the standpoint of size of damage detection, it is found that the first POD mode is quite sensitive to a small defect located at one of the propeller tips. Damage size sensitivity is distributed and depends on the sensor-defect relative distance. It is enhanced considerably in regimes of initial wave-vibration transients. Using the POD modal structure, damage indices are introduced and computed at the first-POD energy level. Accurate estimates for dissipation factor are obtained via the non-linear dynamics return map notion. © 2011 The Author(s).	en
heal.publisher	SAGE PUBLICATIONS LTD	en
heal.journalName	Journal of Intelligent Material Systems and Structures	en
dc.identifier.doi	10.1177/1045389X11414088	en
dc.identifier.isi	ISI:000295738100009	en
dc.identifier.volume	22	en
dc.identifier.issue	12	en
dc.identifier.spage	1371	en
dc.identifier.epage	1394	en