Oblique Wave Scattering by A Rectangular Porous Floating Breakwater with Slotted Screens over A Sill-Type Seabed

Oblique Wave Scattering by A Rectangular Porous Floating Breakwater with Slotted Screens over A Sill-Type Seabed

Kottala Panduranga Santanu Koley

Department of Mathematics, Birla Institute of Technology and Science-Pilani, Hyderabad Campus, India

172 - 186
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In this work, oblique wave scattering by a rectangular porous breakwater with slotted screens floating over a sill-type seabed is examined within the frame of linear wave–structure interaction theory. The Sollitt and Cross model is used to analyze the fluid motion inside the rectangular porous break- water. In addition, a quadratic pressure jump condition on the slotted screens is adopted to include the effect of wave height on wave attenuation by the slotted screens. The associated physical problem is handled using an iterative boundary element method. Finally, the scattering coefficients such as the reflection, transmission, energy loss coefficients, and wave forces acting on the rectangular porous structure are analyzed for different wave conditions. The time-dependent displacement profiles for the various instants of time are provided. Further, the influence of different geometries of sill-type bottoms on wave scattering is analyzed. The study concludes that the wave forces on the rectangular structure attain their maximum when the distance between the slotted screen and the porous structure is an integral multiple of the wavelength associated with the incident wave for different submergence drafts.


energy loss coefficient, iterative BEM, porous breakwater, sill-type seabed, slotted screens


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