Numerical modeling investigation of perforated geometry of caisson breakwater under irregular waves by considering porous media

Abstract

The sea is always considered a source for supplying the needs of humans. Breakwaters are one of the most common coastal protection structures. They provide the possibility to exploit the sea by dissipating the wave energy and creating an undisturbed basin for the berthing of ships in ports. One of the many methods used to engender a calm basin or harbor is to build a rigid wall against the waves, this technique is known as the caisson breakwater. Hence, in this investigation, the interactions of an irregular wave with the caisson breakwater are researched utilizing the FLOW-3D software. To calibrate and validate the model, the results in terms of the free surface, pressure on the caisson surface, and overtopping obtained from the numerical modeling are compared against the laboratory studies performed by Lara et al. It is demonstrated that there is a relative consistency between the numerical modeling and laboratory experiments. Previous studies have always changed the caisson breakwater; however, this study uses numerical modeling to investigate a new geometry of the caisson breakwater with the perforated wall. The numerical simulation shows that in the new geometry of the caisson breakwater, the amount of the overtopping, wave reflection, imposed pressure on the structure, imposed pressure, and speed in the concrete block at the base of the structure are considerably abated in comparison with the caisson breakwater with a rigid vertical wall. As the results of the wave overtopping from the caisson breakwater with a perforated wall are compared against euro top 2016 findings, it is suggested to propose a novel non-dimensional number considering the width of the chamber inside the caisson breakwater.