Wave Scattering by Submerged Porous Disk
Publication: Journal of Engineering Mechanics
Volume 120, Issue 12
Abstract
Linearized potential wave theory is applied in the present paper to investigate the phenomenon of wave scattering by a submerged porous disk. By means of the eigenfunction expansion method, harmonic expressions of the velocity potential in terms of unknown constants are obtained in two subregions of the domain by taking into account the boundary conditions on the free surface, the porous disk surface, and sea bottom surface, as well as the Sommerfeld condition at infinity. These unknown constants are then determined by the matching conditions. Variation of the wave height around the disk and the wave load on the disk versus the dimensionless disk radius, the relative water depth, and the porous‐effect parameter is discussed. It is found that the wave scattering by a disk includes a process of focusing wave energy near the rear of the disk for small dimensionless porous‐effect parameters. An increase of the dimensionless porous‐effect parameter decreases the wave height, and the behavior of a porous disk is similar to that of a wave absorber that may lead to setdown for a large disk radius.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 120 • Issue 12 • December 1994
Pages: 2575 - 2587
Copyright
Copyright © 1994 American Society of Civil Engineers.
History
Received: Oct 18, 1993
Published online: Dec 1, 1994
Published in print: Dec 1994
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