船首部形状と波浪中抵抗増加

抄録

The measured value of added resistance in regular head waves of a ship with blunt bow is larger than the calculated one. It is considered that added resistance on the blunt ship in short length waves is mainly due to reflection of an incident wave at the bow. In this paper, the reasons of the difference between calculations and measurements are discussed using following experimental and theoretical studies. The model used in this study is a simplified ship model with three different bow shapes. l) Measurements of diffraction forces in regular head waves when the model is restrained. 2) Measurements and analyses of unsteady wave pattern. 3) Numerical calculations are performed by using the Ray theory to consider the difference of the propagated characteristics of elementary waves near the hull surface of a ship between in the uniform flow field and in the distorted one deformed by the existence of the ship with blunt bow.