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Head-sea diffraction by a slender raft with application to wave-power absorption

Published online by Cambridge University Press:  20 April 2006

Pierre Haren  and
Chiang C. Mei
Pierre Haren
Affiliation:
Parsons Laboratory, Department of Civil Engineering, Massachusetts Institute of Technology, Cambridge, Mass. 02139
Chiang C. Mei
Affiliation:
Parsons Laboratory, Department of Civil Engineering, Massachusetts Institute of Technology, Cambridge, Mass. 02139
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Abstract

The parabolic approximation which has recently been found to be useful in other physical contexts, is extended to head-sea diffraction of short waves by a slender raft on deep water. In particular, it is a much more direct way of getting the inner approximation of the outer solution in a scheme of matched asymptotics than the original method of Faltinsen (1971). The present results are compared with a more involved integral equation method and are found to be remarkably accurate even when the raft length is comparable to the wavelength. Finally, the asymptotic method is modified for a compliant raft which absorbs wave power by suitably controlled impedance. Optimum efficiency and other performance characteristics are predicted.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 104 , March 1981 , pp. 505 - 526
Copyright
© 1981 Cambridge University Press

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