Triggering mechanisms of limit cycle oscillations due to aeroelastic instability

Lee, YS; Vakakis, AF; Bergman, LA; McFarland, DM; Kerschen, G

dc.contributor.author	Lee, YS	en
dc.contributor.author	Vakakis, AF	en
dc.contributor.author	Bergman, LA	en
dc.contributor.author	McFarland, DM	en
dc.contributor.author	Kerschen, G	en
dc.date.accessioned	2014-03-01T01:23:17Z
dc.date.available	2014-03-01T01:23:17Z
dc.date.issued	2005	en
dc.identifier.issn	0889-9746	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/16884
dc.subject	Aeroelastic instability	en
dc.subject	Limit cycle oscillation (LCO)	en
dc.subject	Numerical continuation	en
dc.subject	Resonance capture	en
dc.subject	Triggering mechanism	en
dc.subject.classification	Engineering, Mechanical	en
dc.subject.classification	Mechanics	en
dc.subject.other	Aerodynamics	en
dc.subject.other	Bifurcation (mathematics)	en
dc.subject.other	Degrees of freedom (mechanics)	en
dc.subject.other	Mathematical models	en
dc.subject.other	Oscillations	en
dc.subject.other	Resonance	en
dc.subject.other	Stability	en
dc.subject.other	Stiffness	en
dc.subject.other	Wavelet transforms	en
dc.subject.other	Aeroelasticity instability	en
dc.subject.other	Limit cycle oscillation (LCO)	en
dc.subject.other	Numerical continuation	en
dc.subject.other	Resonance capture	en
dc.subject.other	Triggering mechanism	en
dc.subject.other	Fluid structure interaction	en
dc.subject.other	aeroelasticity	en
dc.subject.other	fluid-structure interaction	en
dc.subject.other	instability	en
dc.subject.other	mathematical analysis	en
dc.subject.other	subsonic flow	en
dc.subject.other	wing	en
dc.title	Triggering mechanisms of limit cycle oscillations due to aeroelastic instability	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.jfluidstructs.2005.08.011	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.jfluidstructs.2005.08.011	en
heal.language	English	en
heal.publicationDate	2005	en
heal.abstract	We show that a cascade of resonance captures constitutes the triggering mechanism of limit cycle oscillations (LCOs) due to aeroelastic instability of rigid wings in flow. We consider a two-degree-of-freedom (2-dof) wing model in subsonic flow with cubic nonlinear stiffnesses at the support. Under the assumption of quasi-steady aerodynamics, we apply a complexification/averaging technique to express the dynamics of fluid-structure interactions in terms of three fast-frequency components; these are the two linear natural frequencies corresponding to heave and pitch, and a superharmonic at three times the pitch frequency. Bifurcation analysis of the resulting set of modulation equations governing the slow dynamics is carried out via the method of numerical continuation, and reveals the different types of steady state motions realized as parameters vary. It turns out that the LCO triggering mechanism consists of a combination of different dynamic phenomena, taking place at three main stages or regimes: attraction to transient resonance captures (TRCs), escapes from these captures and, finally, entrapments into permanent resonance captures (PRCs). We examine numerically and analytically the dynamics at each of these stages by means of wavelet transform analysis, study of the evolution of appropriately defined phase variables in projections of the phase space of the dynamics, and analysis of instantaneous energy exchanges between the various nonlinear modes involved. The general conclusion is that an initial excitation of the heave mode by the flow acts as the triggering mechanism for the excitation of the pitch mode through nonlinear interactions resulting from the resonance captures and escapes. The eventual excitation of the pitch mode signifies the appearance of an LCO of the in-flow wing. (c) 2005 Elsevier Ltd. All rights reserved.	en
heal.publisher	ACADEMIC PRESS LTD ELSEVIER SCIENCE LTD	en
heal.journalName	Journal of Fluids and Structures	en
dc.identifier.doi	10.1016/j.jfluidstructs.2005.08.011	en
dc.identifier.isi	ISI:000233841700004	en
dc.identifier.volume	21	en
dc.identifier.issue	5-7 SPEC. ISS.	en
dc.identifier.spage	485	en
dc.identifier.epage	529	en