船体固有振動数に対する水深影響の一計算法

概要

論文の詳細を見る
An experiment has been carried out at the laboratory of Prof. Kumai to find the effect of shallow water upon the added virtual mass of the cylinder models of the typical sections of cargo ship, especially great emphasis being placed on the effect of breadth-draught ratio.As the result of this experiment, the increase fraction of the added virtual mass due to shallow water (c) was disclosed as follows : c=1.1β^3(b/d)(d/h)^<2.2>where, β : area coefficient of section b : breadth of section d : draught h : depth of water In the case of ship's form, the increase-fraction (C) deduced when applying the above formula for lines of hulls can be expressed as follows : C=1.19(B/d)(d/h)^<2.>C_b where, B : moulded breadth C_b : block coefficient The natural frequencies at shallow water can be estimated according to the method described in the auther's previous paper : "The Estimation of the Principal Natural Frequencies of Hull", and the coefficients of the increased added virtual mass necessary for the frequencies calculation are given in Fig.3.After comparison was given to the measured data and the calculated ones, this method has been confirmed to be satisfactory for practical use.
社団法人日本船舶海洋工学会の論文