Wave loads acted on an array of truncated cylinders with upper porous sidewall

In this paper, an analytical model is proposed to investigate the wave loads acting on an array of truncated cylinders with an upper porous sidewall in finite water depth, based on the linear potential flow theory. In the local coordinate system of each cylinder, the velocity potentials in the interior and exterior domains of the body surface of each cylinder could be mathematically expressed according to the eigen-function matching technique. The interior-region Graf’s addition theorem is applied to rewrite each exterior-domain velocity potential, which is expressed in its own coordinate system, into one prescribed cylindrical coordinate system. Then, the unknown coefficients in the velocity potentials are solved by matching the velocity and pressure at each cylinder surface. An indirect identity regarding energy dissipation caused by the array of porous structures is derived to validate the model by comparing it with the directly calculated wave energy flux loss through the array. Following the validation, the analytical model is performed to investigate the effects of the incident wave direction, opening angle, draft, porosity of this porous sidewall, and the number of cylinders on wave loads. Introducing the upper porous sidewall markedly decreases horizontal and vertical hydrodynamic loads on the array of cylinders compared with an impermeable configuration, especially in the low-frequency range.