Bounded and unbounded coupled transverse response of parametrically excited vertical marine risers and tensioned cable legs for marine applications

Chatjigeorgiou, IK; Mavrakos, SA

dc.contributor.author	Chatjigeorgiou, IK	en
dc.contributor.author	Mavrakos, SA	en
dc.date.accessioned	2014-03-01T01:17:35Z
dc.date.available	2014-03-01T01:17:35Z
dc.date.issued	2002	en
dc.identifier.issn	0141-1187	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/14576
dc.subject	Marine risers	en
dc.subject	Mathieu instabilities	en
dc.subject	Parametric excitation	en
dc.subject.classification	Engineering, Ocean	en
dc.subject.classification	Oceanography	en
dc.subject.other	Dynamic response	en
dc.subject.other	Elasticity	en
dc.subject.other	Hydrodynamics	en
dc.subject.other	Underground structures	en
dc.subject.other	Dynamic systems	en
dc.subject.other	Marine applications	en
dc.subject.other	dynamic response	en
dc.subject.other	riser	en
dc.subject.other	tension leg platform	en
dc.subject.other	dynamic response	en
dc.subject.other	offshore structure	en
dc.subject.other	riser	en
dc.subject.other	tension leg platform	en
dc.title	Bounded and unbounded coupled transverse response of parametrically excited vertical marine risers and tensioned cable legs for marine applications	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0141-1187(03)00017-8	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0141-1187(03)00017-8	en
heal.language	English	en
heal.publicationDate	2002	en
heal.abstract	The paper deals with the non-linear dynamic response in the transverse direction of vertical marine risers or a tensioned cable legs subjected to parametric excitation at the top of the structure. The dynamic model contains both elastic and bending effects. The analytical approach reveals that the dynamic lateral response is governed by effects originated from the coupling of modes in transverse direction. The mathematical model is being treated numerically by retaining a sufficient number of transverse modes. Numerical results are given for specific case studies and refer both to the time histories of the lateral response for all modes of motion, and to the corresponding power spectral densities obtained through FFT. The numerical predictions are suitably plotted and discussed. The calculations concern both the undamped and the damped dynamic system. The damping in the system is a non-linear Morison type term, which describes the effect of the hydrodynamic drag. Both coupled and uncoupled equations are treated and points as well as regions of coupled and uncoupled stability and instability are defined. It is shown that the impacts originated from the coupling, evaluate new instabilities for the respective undamped system. The numerical results obtained through FFT of the time histories, provide qualitative conclusions for the features of the dynamic response for the modes of motions considered. Special attention has been paid to the effect of the hydrodynamic drag for the parametric excitation frequencies that guide the dynamic system to lie within a region of coupled instability. (C) 2003 Elsevier Science Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	Applied Ocean Research	en
dc.identifier.doi	10.1016/S0141-1187(03)00017-8	en
dc.identifier.isi	ISI:000184046100004	en
dc.identifier.volume	24	en
dc.identifier.issue	6	en
dc.identifier.spage	341	en
dc.identifier.epage	354	en