Formula for wave transmission at submerged homogeneous porous breakwaters

A new formula is introduced to determine the wave transmission at submerged porous breakwaters highlighting the effect of the wave-induced pore pressure distribution inside the breakwater, applicable for both regular and random waves. A CFD numerical wave flume based on the Stokes-Cnoidal wave theory for regular waves and Pierson-Moskowitz spectrum theory for random waves combined with the Forchheimer formula is calibrated using an experimental dataset from Calabrese et al. (2002). The proposed formula for the wave transmission coefficient has been obtained by means of dimensional analysis and incomplete self-similarity, and it has been calibrated using the results of the numerical experiments. The new formula has been verified using a large database on wave transmission coefficient yield fairing good predictions for a wide range of wave conditions and breakwater geometries. The proposed formula has been compared with other existing formulae applying to 2336 data of the existing wave transmission coefficient dataset where the proposed formula giving the minimum root mean square error Erms = 12.6% showed the maximum accuracy among all other existing formulae for determining the wave transmission coefficient over the submerged porous breakwaters.