1 0 0 0 OA 水中翼のキャビテーション性能計算法について
- 著者
- 石井 規夫 新井 和夫 都丸 祐司 増山 和雄 清水 健
- 出版者
- 公益社団法人日本船舶海洋工学会
- 雑誌
- 関西造船協会誌 (ISSN:03899101)
- 巻号頁・発行日
- no.221, pp.43-48, 1994-03-25
This paper presents a numerical method for predicting the hydrodynamic and cavitation performance of a submerged hydrofoil. The numerical model of a hydrofoil is constructed with a hydrofoil and center and side struts. It is also taken account of the effect of the controll of flaps. The method represents a hydrofoil and struts by discrete vortices and line sources located on the camber surface of the hydrofoil and strut. The effect of the water surface is considered approximately by the image system in the present method. A three-dimensional theoretical procedure is used to calculate partial-and super-cavitation occurring on the hydrofoil surface. In order to verify the validity of the method, the lift and drag acting on the hydrofoil and the extent of the cavity occurring on the back or face surface of the hydrofoil were calculated and compared with the test results which was carried out in the cavitation tunnel of Akishima Laboratories (MITSUI ZOSEN) Inc. The comparisons show that the present method becomes a very useful tool for designing the hydrofoils of a high speed craft.
1 0 0 0 プロペラ後流渦と揚力面の数値解析
In recent years, a highly advanced lifting surface method with high accuracy has been required in order to design the various types of propellers which demand high efficiency and to reduce ship vibration and noise. In this paper, an improved lifting surface procedure based on the vortex lattice method is presented. For the determination of a trailing vortex wake geometory, a numerical iterative procedure is described. The numerical results on propeller slipstream give a good agreement with the measured values by laser doppler velocimeter. The present method is applied to calculate the open water characteristics of a propeller. And a quasi-steady technique based on the present method is adopted to calculate the fluctuation of propeller forces and cavitation patterns behind the ship's wake field. The advantages of the present method are shown by comparing the numerical results with the experimental data of conventional and highly skewed propeller.