SPH modelling of wave attenuation by an array of submerged resonators and vorticity generation mechanism

Abstract The present research aims to numerically analyze the attenuation of waves by a novel device designed to address coastal erosion through an innovative and environmentally friendly approach. The device consists of an array of submerged resonators inspired by the concept of metamaterial wave control. Through their oscillatory movement induced by wave action, these resonators achieve significant wave attenuation driven by viscous dissipation mechanisms. However, the study of metamaterials in the field of water waves remains challenging due to its complexity. Further studies are required to refine the scaling and improve the correspondence to natural beach conditions and to a deeper understanding of the intrinsic (e.g. broad-banded sea) and practical (e.g. mooring, navigation, durability, local scouring processes) limitations. This numerical study shows that, with appropriate particle resolution, the coupling between DualSPHysics and MoorDyn executed on a GPU architecture can accurately predict the motion of moored floating structures when they interact with the free surface making it a useful method for modeling these problems. We investigated the vorticity generation mechanism related to the motion of the wave and the cylinders. The vorticities near the cylinders are shown to be closely related to the motion of both the waves and the cylinders, with the maximum vorticities being enhanced by the natural vorticity of the moving wave. Correspondences emerge between the normalized frequency spectra of the cylinder surges and the vorticities on both sides of the cylinder. Instead, the movement of the cylinders also creates a wake behind the cylinders, which has a tendency to spread downward.