Wave attenuation over a submerged porous media

Abstract

In this paper, a numerical modeling for free surface flows over submerged porous media is outlined. The governing equations used are two layers linear shallow water model. For flow in a submerged porous medium, linear friction resistance is included in momentum equation. Solving the linearized full governing equations analytically, we can obtain dispersion relation that holds for gravity waves over submerged porous media. This dispersion relation explain diffusive mechanism of the porous structure. Numerically, finite volume on a staggered grid is implemented to solve these equations. Numerical simulation of incoming waves over porous media shows the wave amplitude is attenuated because of the porous structure. The validity of this numerical model is confirmed with analytical result.