Wave resonance mitigation using a rigid submerged breakwater in a varying-width channel

Abstract

This paper digs deeper into the phenomenon of wave oscillation that is caused by external forces, such as air pressure and seismic vibrations. This would eventually lead to potentially dire consequences, particularly in coastal areas. In order to solve this issue, this study focuses on adding a rigid breakwater at the bottom of the basin to minimize the aforementioned damages. We will be looking at a semi-closed basin with triangular width and either constant or triangular depth, to which is added one block of the submerged breakwater with smooth and rough surfaces. We will employ the modified shallow water equations to obtain the analytical natural period for each basin type. After that, numerical simulations are carried out to check the presence of resonance phenomena in each basin. Additionally, the study investigates the crucial role of the friction coefficient in preventing resonance in basins with rough-surfaced submerged breakwaters. The aim is to explore whether a single block of smooth-surfaced submerged breakwater is sufficient to eliminate resonance or whether other conditions are necessary to halt the resonance phenomenon in each basin. Ultimately, the findings of this study hold potential benefits for individuals involved in the planning and construction of harbors and protective structures. By gaining a deeper understanding of wave oscillation and resonance in semi-closed basins, the research aims to contribute valuable insights for creating more effective and resilient coastal protection measures.