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Hydroelastic response of floating elastic discs to regular waves. Part 2. Modal analysis

Published online by Cambridge University Press:  16 April 2013

F. Montiel*
Affiliation:
Department of Mathematics and Statistics, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
L. G. Bennetts
Affiliation:
School of Mathematical Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
V. A. Squire
Affiliation:
Department of Mathematics and Statistics, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
F. Bonnefoy
Affiliation:
Laboratoire de recherche en Hydrodynamique, Énergétique et Environnement Atmosphérique, École Centrale de Nantes, 1 rue de la Noë, Nantes, France
P. Ferrant
Affiliation:
Laboratoire de recherche en Hydrodynamique, Énergétique et Environnement Atmosphérique, École Centrale de Nantes, 1 rue de la Noë, Nantes, France
*
Email address for correspondence: [email protected]

Abstract

Validation of a linear numerical model of wave interactions with floating compliant discs is sought using data obtained from the wave basin experiments reported in Part 1 (Montiel et al. J. Fluid Mech., vol. 723, 2013, pp. 604–628). Comparisons are made for both single-disc tests and the two-disc tests in which wave interactions between discs are observed. The deflection of the disc or discs is separated into the natural modes of vibration in vacuo. The decomposition allows the rigid-body motions and flexural motions to be analysed separately. Rigid-body motions are accurately replicated by the numerical model but, although passable agreement is found, the amplitudes of flexural modes are consistently overestimated. Extensions of the numerical model are used to discount the experimental configuration as a source of the discrepancies. An enhanced viscoelastic model for the discs is also proposed, which results in improved model/data agreement for the flexural motions but cannot account for all of the disagreement.

Type
Papers
Copyright
©2013 Cambridge University Press 

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