A coupled-mode technique for weakly nonlinear wave interaction with large floating structures lying over variable bathymetry regions

Belibassakis, KA; Athanassoulis, GA

dc.contributor.author	Belibassakis, KA	en
dc.contributor.author	Athanassoulis, GA	en
dc.date.accessioned	2014-03-01T01:23:23Z
dc.date.available	2014-03-01T01:23:23Z
dc.date.issued	2006	en
dc.identifier.issn	0141-1187	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/16939
dc.subject	Coupled modes	en
dc.subject	Nonlinear hydroelastic analysis	en
dc.subject	Variable bathymetry	en
dc.subject	Very large floating structures	en
dc.subject.classification	Engineering, Ocean	en
dc.subject.classification	Oceanography	en
dc.subject.other	Bathymetry	en
dc.subject.other	Boundary conditions	en
dc.subject.other	Fluid structure interaction	en
dc.subject.other	Hydroelasticity	en
dc.subject.other	Mathematical models	en
dc.subject.other	Ocean structures	en
dc.subject.other	Plates (structural components)	en
dc.subject.other	Water waves	en
dc.subject.other	Coupled-mode technique	en
dc.subject.other	Floating structures	en
dc.subject.other	Nonlinear hydroelastic analysis	en
dc.subject.other	Oceanography	en
dc.subject.other	Bathymetry	en
dc.subject.other	Boundary conditions	en
dc.subject.other	Fluid structure interaction	en
dc.subject.other	Hydroelasticity	en
dc.subject.other	Mathematical models	en
dc.subject.other	Ocean structures	en
dc.subject.other	Oceanography	en
dc.subject.other	Plates (structural components)	en
dc.subject.other	Water waves	en
dc.subject.other	bathymetry	en
dc.subject.other	floating structure	en
dc.subject.other	hydroelasticity	en
dc.subject.other	nonlinear wave	en
dc.subject.other	offshore engineering	en
dc.subject.other	surface wave	en
dc.subject.other	wave propagation	en
dc.title	A coupled-mode technique for weakly nonlinear wave interaction with large floating structures lying over variable bathymetry regions	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.apor.2005.12.003	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.apor.2005.12.003	en
heal.language	English	en
heal.publicationDate	2006	en
heal.abstract	A coupled-mode method is developed and applied to hydroelastic analysis of large floating platforms of shallow draft over variable bathymetry regions, characterised by parallel bottom contours. We consider the scattering problem of surface waves, under the combined effects of variable bathymetry and a semi-infinite floating elastic plate, in the time domain. The present development is based on appropriate generalisation of the unconstrained variational principle of Luke [Luke JC. A variational principle for a fluid with a free surface. J Fluid Mech 1967;27:395-7], which models the evolution of nonlinear water waves in intermediate water depth over a general bathymetry. Assuming small plate deflections and neglecting the rotation of plate section, the large floating structure has been modelled as a thin elastic plate. The present approach is based on appropriate extensions of the nonlinear coupled-mode model developed by Athanassoulis and Belibassakis, [A nonlinear coupled-mode model for water waves over a general bathymetry. In: Proc. 21st international conference on offshore mechanics and arctic engineering OMAE 2002. 2002] for waves propagating in variable bathymetry regions. In order to consistently treat the wave field beneath the elastic floating plate down to the sloping bottom boundary, a complete, local-mode series expansion of the wave field is used, enhanced by appropriate sloping-bottom and free-surface modes. The latter enable consistent satisfaction of the Neumann bottom-boundary condition on a general topography, as well as the kinematical conditions on the free surface and on the elastic plate surface. By introducing this expansion into the variational principle, an equivalent coupled-mode system of horizontal equations is derived, fully accounting for the effects of nonlinearity and dispersion. Boundary conditions are also provided by the variational principle, ensuring that the edges of the plate are free of moment and shear force. Numerical results concerning floating structures lying over sloping seabeds are presented, as obtained by simplifying the fully nonlinear coupled-mode system, keeping only up to second-order terms. The present method can be extended to treat large floating elastic bodies or structures characterised by variable thickness (draft), flexural rigidity and mass distributions. (c) 2006 Elsevier Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	Applied Ocean Research	en
dc.identifier.doi	10.1016/j.apor.2005.12.003	en
dc.identifier.isi	ISI:000241478500006	en
dc.identifier.volume	28	en
dc.identifier.issue	1	en
dc.identifier.spage	59	en
dc.identifier.epage	76	en