Development of Simplified Formulae for Added Mass of a 2-D Floating Body with a Semi-Circle Section in a Finite Water Depth

유한 수심에서 반원형 부유체의 부가질량계수 약산식 개발

Koo, Weoncheol;Kim, Jun-Dong

  • Received : 2013.01.14
  • Accepted : 2013.02.14
  • Published : 2013.02.28


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


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Supported by : 울산대학교