Hydrodynamic Forces Characteristics of a Circular Cylinder with a Damping Plate

doi:2011.25.1.1

J. Ocean Eng. Technol. > Volume 25(1); 2011 > Article

J. Ocean Eng. Technol. 2011;25(1):1-7.
DOI: https://doi.org/10.5574/KSOE.2011.25.1.001

Cho Il-Hyoung

Department of Ocean System Engineering Jeju National University

감쇠판이 부착된 원기둥의 동유체력 특성

조일형

제주대학교 해양시스템공학

Keywords: Hydrodynamic force, Added mass, Damping coefficient, Eigenfunction expansion method, Damping plate

핵심용어: 동유체력, 부가질량, 감쇠계수, 고유함수전개법, 감쇠판

Abstract

The radiation of water waves by a heaving truncated circular cylinder with damping plate is solved in the frame of the three-dimensional linear potential theory. The damping plate has a distinct advantage in reducing the motion response of a floating circular cylinder by increasing the added mass and the damping coefficient. Using the matched eigenfunction expansion method, the characteristics of hydrodynamic added mass and the damping coefficient are investigated with various system parameters, such as the radius and submergence depth of the damping plate. It is found that both added mass and the damping coefficient are significantly increased due to the arranged features of the larger damping plate with shallow submergence, which are positive factors as a motion reduction device of the floating offshore platform. Also the numerical results for an oscillating submerged disk show that the added mass is negative and that the damping coefficient has a peak value at resonant frequency when submergence depth is sufficiently small.