Wave Control by an Array of Porous Dual Cylindrical Structures

J. Ocean Eng. Technol. 2004;18(5):7-14.

CHO IL-HYOUNG

투과성 이중 원통구조물 배열에 의한 파랑제어

조일형

제주대학교 해양산업공학부

Keywords: Porous Cylindrical Structure, Wave Control, Seawater Exchanging Breakwater, Eigenfunction Expansion Method, Porous Coefficient, Wave Run-up

핵심용어: 투과성 원통구조물, 파랑제어, 해수교환 방파제, 고유함수 전개법, 공극율 계수, 파 처올림

Abstract

The interaction of incident manochromatic waves with an array of N surface-piercing porous dual cylindrical structures is investigated in the frame of three-dimensional linear potential theory. The dual cylindrical structure is camposed of concentric two cylinders. The exterior cylinder is porous and the interior cylinder is impermeable. The fluid domain is divided into N+1 regions i.e. a single exterior region and N interior regions. The diffraction potentials in each region representing the scattering of incident waves by an array of porous cylindrical structures are expressed by the Fourier Bessel series. The unknown coefficients in each region are determined by applying the porous boundary condition and continuity of mass flux at the matching boundary. It is found that an array of porous cylindrical structures reduces both the wave forces and the wave run-up, and shows the excellent performance of wave blocking. The results show that various types of breakwater exchanging seawater are prospective by controlling the porosity and the configuration of cylindrical structures.