Development of Simplified Formulae for Added Mass of a 2-D Floating Body with a Semi-Circle Section in a Finite Water Depth Koo, Weoncheol; Kim, Jun-Dong;
This study is to develop the simplified formulae for added mass coefficient of a 2-D floating body with a semi-circle section in a finite water depth. The semi-circle floating body may represent a simplified midship section transformed by Lewis form, which can be used for the ship motion analysis by strip theory. Since the added mass coefficient varies with motion frequencies and sea bottom effect, the correction factor representing the effect of water depth and frequencies is developed for accurate prediction of added mass. Using a two-dimensional numerical wave tank (NWT) technique based on the boundary element method (BEM) including sea bottom boundary the reference values of added mass are calculated to develop the correction factor. For verification and effectiveness of the formulae, the predicted added mass coefficients for various frequencies and water depth ratios are compared with the calculated values from NWT technique.
Added mass;Simplified formulae;Boundary element method;Frequency domain;Floating body;Finite water depth;Correction factor;
Simplified formulas of heave added mass coefficients at high frequency for various two-dimensional bodies in a finite water depth, International Journal of Naval Architecture and Ocean Engineering, 2015, 7, 1, 115
Frank, W., 1968. Oscillation of Cylinders in or Below the Free Surface of Deep Fluids. Hydromechanics Laboratory Research and Development Report 2375.
Kim, J.D., Choi, M.G., Koo, W.C., 2012. Development of Simplified Formulae for Added Mass of a Floating Body in a Finite Water Depth, Proceedings of the Annual Meeting, KAOSTS, Daegu. Republic of Korea, 1171-1174.
Lewis, E.V., 1989. Principal of Naval Architecture. Second revision. The Society of Naval Architects and Marine Engineers.
Ursell, F., 1948. On the Heaving Motion of a Circular Cylinder on the Surface of a Fluid. Quarterly Journal of Mechanics and Applied Mathematics, 2(2), 218-231.
Vugts, J.H., 1968. The Hydrodynamic Coefficients for Swaying, Heaving and Rolling Cylinders in a Free Surface. Netherlands Ship Res. Centre TNO. Report No. 112S, and Int. Shipbldg. Prog. 15.