This paper describes an attempt of improving ship hull form, for minimizing ship viscous resistance. The method adopted here represents the hull-form variation function using B-spline function, takes the coefficients of the B-spline as the design variables, and evaluates the viscous resistance value by Computational Fluid Dynamics (CFD) method, called NICE Code developed by Kodama. Then a feasible direction method is applied to the optimizing process including the above procedure of viscous resistance computation. It is found that the convergence of the iterative optimizing process is steady, and that the method is useful for practical initial design of ship forms, although it also leaves some aspects of improvement such as accuracy of the sensitivity coefficients.

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In ocean going fine ships such as container ships with high power main engine, it seems almost impossible to improve their propulsive performance to a large extent so far as the conventional stern form is used. The reason is that severe design condition such as a draft restriction, TKM (transverse metacentric height) requirement and propeller tip clearance requirement, restrict the propeller diameter and the stern form modification to a narrow range. This paper describes the change with year of these restrictions and the influence of these restrictions on the propulsive performance mainly on TKM, and a new stern form developed by the authors.

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This paper describes a very compact CMT apparatus (2.00 m W × 1.00 m D × 1.00 m H) and its applications for captive test of oblique, pure turning, pure sway and pure yaw motion. The paper presents the measured results of hydrodynamic forces acting on a block-typed ship in oblique or tough turning motion by means of CMT apparatus only, and in tender turning motion using CMT apparatus and towing carriage in the ordinary towing tank. Here our intention is to contrive the new method of convenient experiment-systems instead of huge CMT apparatus and huge amount of time for experiments.

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