Water-Wave Diffraction by Thin Porous Breakwater

Abstract

The linearized theory of water waves is used to study the diffraction of an incident plane wave by a thin porous vertical breakwater of semi-infinite extent. Under the assumption that the wavelength is much greater than the breakwater thickness, the breakwater is replaced by a thin permeable barrier and a suitable boundary condition applied on the barrier. An explicit solution, found by the Wiener-Hopf technique, is presented for the barrier diffraction problem and then easily computable asymptotic forms are derived. Results are presented to illustrate the effects of porosity and variable angle of wave incidence.