Wave Interaction with a Porous Circular Cylinder of Non-Uniform Porosity

J. Ocean Eng. Technol. 2009;23(6):23-31.

Cho Il-Hyoung

Department of Ocean System Engineering Jeju National University

비 균일한 공극율을 갖는 투과성 원기둥과 파의 상호작용

조일형

제주대학교 해양시스템공학과

Keywords: Porous circular cylinder, Wave deformation, Breakwater, Eigenfunction expansion method, Wave force

핵심용어: 투과성 원기둥, 파랑변형, 방파제, 고유함수전개법, 파랑하중

Abstract

The interaction of incident monochromatic waves with a bottom-mounted vertical porous circular cylinder is investigated using the framework of the three-dimensional linear potential theory. The porosity of the circular cylinder is uniform vertically but varies in the circumferential direction. By adjusting the porosities of the circular cylinder, both the wave blocking performance of a porous semi-circular breakwater and the wave responses inside a circular harbor with an entrance are applied as calculation examples. It is found that the reflected waves, wave run-up, and wave forces are significantly reduced due to wall porosity, which are positive factors for a breakwater, and the amplification factor of a circular harbor at resonant frequencies is greatly reduced by a porous sidewall.