Water Waves above Submerged Porous Plate

Abstract

Wave motion over a submerged porous plate is studied by the boundary‐element method based on the linear potential wave theory. The boundary condition at the porous plate is formulated under the assumption that the flow within the porous medium is governed by Darcy's law. The characteristics of variation of the reflection, the transmission, the loss of energy and the force versus the plate length, the water depth, the incident wavelength, the depth of submergence, and the porosity of the plate are discussed. It is shown that the reflection and transmission coefficients vary periodically as the relative length of the plate to the incident wavelength increases. Moderately large values of the porosity of the plate are found to produce the maximum dissipation of the incident wave energy. It is also demonstrated that a plate with proper porosity can significantly suppress the reflection and reduce the wave force acting on it while the transmission can be kept at a low level.