Trapping and Generation of Waves by Vertical Porous Structures
Publication: Journal of Engineering Mechanics
Volume 126, Issue 10
Abstract
The trapping and generation of surface waves by submerged vertical permeable barriers or plates kept at one end of a semi-infinitely long channel of finite depth are investigated for various barrier and plate configurations. The various fixed barrier configurations are (1) a surface-piercing barrier; (2) a bottom-touching barrier; (3) a barrier with a gap; and (4) a fully submerged barrier. The different moving plate (or wavemaker) configurations are of types 1, 2, and 4, respectively. The boundary value problems are converted to dual/triple series relations by a suitable application of the eigenfunction expansion method and then the full solutions are obtained by the least-squares method. The variations of reflection coefficients are obtained and discussed for different values of the porous-effect parameter, the normalized distance between the barrier and the channel end-wall, and the length of submergence of barriers for all types of barrier configurations. The dynamic pressure distributions for various porous-effect parameters are analyzed for the three types of wavemakers. The wave amplitudes at large distances are obtained and analyzed for different values of the porous-effect parameter and the distance between the wavemaker and the channel end-wall.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 126 • Issue 10 • October 2000
Pages: 1074 - 1082
History
Received: Sep 7, 1999
Published online: Oct 1, 2000
Published in print: Oct 2000
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