Conference article

The Wave Excitation Forces on a Floating Vertical Cylinder in Water of Infinite Depth

William Finnegan
College of Engineering and Informatics, National University of Ireland, Galway, Ireland

Martin Meere
School of Mathematics, Statistics and Applied Mathematics, National University of Ireland, Galway, Ireland

Jamie Goggins
Ryan Institute for Environmental, Marine and Energy Research, National University of Ireland, Galway, Ireland

Download articlehttp://dx.doi.org/10.3384/ecp110572175

Published in: World Renewable Energy Congress - Sweden; 8-13 May; 2011; Linköping; Sweden

Linköping Electronic Conference Proceedings 57:5, p. 2175-2182

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Published: 2011-11-03

ISBN: 978-91-7393-070-3

ISSN: 1650-3686 (print), 1650-3740 (online)

Abstract

When carrying out any numerical modeling it is vital to have an analytical approximation to insure that realistic results are obtained. The numerical modeling of wave energy converters is an efficient and inexpensive method of undertaking initial optimisation and experimentation. Therefore; the main objective of this paper is to determine an analytical solution for the heave; surge and pitch wave excitation forces on a floating cylinder in water of infinite depth. The boundary value problem technique; using the method of separation of variables; is employed to derive the velocity potentials throughout the fluid domain. A Fourier transform is used to represent infinite depth. Additionally; Havelock’s expansion theorem is used to invert the complicated combined Fourier sine/cosine transform. An asymptotic approximation is taken for low frequency incident waves in order to create an analytical solution to the problem. Graphical representations of the wave excitation forces with respect to incident wave frequencies for various draft to radius ratios are presented; which can easily be used in the design of wave energy converters.

Keywords

Infinite depth; Wave energy; Wave structure interaction; Wave water problem

References

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