商船型模型船の横搖試驗成績に就て

概要

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For the purpose of investigating the resistance to the rolling of ships and the apparent moment of inertia, four merchant ship models were made to rollinstill water with the moment of inertia varied but with the displacement and the metacentric height kept constant. Experiments on the rolling among waves were also carried ont with these models in their original conditions, the maximum surface wave slope being kept nearly constant for one series of tests. From these experiments it was found that : -1. The coefficients of passive resistance to the rolling among waves varies with the period of roll or waves ; 2. The effective coefficient of equivalent passive resistance assumed to vary as the angular velocity is approximately expressed in the form αω=1/T_s(T_s/T_ω)^n・δθ_m/θ_m ; 3. The apparent moment of inertia of ships rolling among nearly synchronous waves is approximately written as I_ω=I_o{1+(ψ(δθ_m/θ_m-α))/(1-ψ(δθ_m)/(θ_m))(T_3^2)/(T_w^2)} ; 4. The parameters of the active resistance vary irregularly with the ratio T_w/T_o, but in general this resistance increases the angle of roll when T_w/T_o is less than unity and vice versa ; 5. The angles of synchronons rolling calculated by neglecting the active resistance are nearly equal to the experimental values.
社団法人日本船舶海洋工学会の論文
1943-12-30