Wave energy dissipation of a submerged horizontal flexible porous membrane under oblique wave interaction

Abstract

An analytical model associated with oblique wave interaction with a submerged horizontal flexible porous membrane is presented under the assumption of linearized small amplitude and structural response in finite water depth. The expansion formula associated with Green's functions using fundamental source potentials based on reduced wave equation is derived. Further, a physical problem of oblique wave interaction with a moored finite horizontal submerged flexible porous membrane on wave energy dissipation is illustrated to analyse the different design parameter based on matched eigenfunction expansion method. The roots of the complex dispersion relation are obtained by applying a perturbation scheme and the accuracy of the numerical computation is demonstrated by analysing the convergence of reflection, transmission, and dissipation coefficients for different spring stiffness and porous-effect parameters. Further, the correctness of the present solution is checked by validating against analytical, numerical boundary element method, and experimental data available in the literature. The effects of spring stiffness, porous-effect parameter, submergence depth, structural length, angle of incidence, and flow pattern on reflection, transmission, dissipation coefficients, membrane deflection, vertical force, and contour plots are analysed. The present analysis on different design parameters will be helpful for better understanding for engineers to design as an effective breakwater/wave absorber.