A numerical approach for simulating flow through thin porous media

In this study we develop a formulation to model the effect of a thin porous plate of arbitrary geometry in a fluid flow. This underlying model is based on the 1D pressure drop in the normal direction to the plate and is easily used for 2D and 3D flows. Our primary interest lies in perforated plates for use in ocean wave damping applications, although other porous media such as woven gauze or slotted screens can be handled in an identical manner. We implement the model in a Smoothed Particle Hydrodynamics (SPH) framework which is an intrinsically suitable method for the interaction between complex geometries and ocean waves. We compare predictions of the method to theory and available experimental data in a set of simulations including 2D steady-state flow normal and inclined to a screen. In all cases the results from the SPH implementation are in very satisfactory agreement. The method is then demonstrated on solitary wave interaction with a porous barrier and the transmission, reflection and absorption of wave energy is predicted as a function of permeability.