Analysis of water wave interaction with multiple submerged semi-circular porous structures

Abstract

The impact of an array of bottom-mounted semi-circular breakwaters on wave scattering and trapping is investigated. Under the assumption of linear water wave theory, a computational solution is developed using the methods of eigenfunction expansion and multi-domain boundary element. In order to understand how different structural and wave characteristics affect wave flow, the reflection, transmission and dissipation factors are evaluated and investigated. The study reveals that the Bragg reflection happens when a series of porous semi-circular breakwaters scatter waves. In addition, the presence of four structures causes nearly 80% of the wave energy to dissipate. As the number of semi-circular breakwaters rises, the hydrodynamic forces acting on the impermeable sea wall greatly reduce. The study concludes that the number of structures, radius and porous-effect parameters of the structures plays a vital role in wave reflection, reducing the hydrodynamic load on the impenetrable sea wall.