Study on Optimum Design Methods for Various Types of Ships

为设计不同类型船舶的船体外形，提出了一些优化方法。得到的结果如下：1. 采用非线性优化技术——SUMT方法，设计了最小阻力船型。(1)船首和船尾有球根的船型比只有球根的船型在抗浪方面更有利。(2)然而，通过模型实验表明，较大的尾泡会导致流动分离和粘滞阻力增大。提出了分离带的估计方法。采用所谓的GRG方法，得到了船舶在波浪中运动的最佳船体形状。(1)减小船舶运动的船型在船首和船尾部分有光滑的v型截面。(2)然而，最小激励力的船体形状波动很大，而力，即弗劳德-克里洛夫力，实际上是最小的。基于流体守恒定律，提出了一种优化地效机翼平面形状的初步理论。(1)半椭圆平面型翼型前缘端板几乎没有抑制翼型前缘出流的作用，反而增加了翼型前缘的法向力。(2)从尾缘向整体拟合30%左右的端板长度对增大法向力最有利。

Some optimizing methods are presented in order to design hull forms of various types of ships. The obtained results are the followings. 1. Minimum resistance ship form with bow and stern bulbs is developed by using a non-linear optimization technique, SUMT method.(1) A ship form with bow and stern bulbs is more favorable in the aspect of wave resistance than the one with only bulbous bow.(2) However, it is made clear by a model experiment that a large stern bulb causes flow separation and increase of viscous resistance. The estimation of separation zone is developed.2. Optimum hull forms for ship motion in wave are obtained by using the so-called GRG method.(1) The hull form minimizing the ship motion has smooth V-shaped sections in bow and stern part.(2) However, the hull form minimizing the exciting force undulates greatly, while the force, Froude-Krylov force, is really minimum.3. A preliminary theory to optimize the plane form of a WIG(Wing in ground-effects) is presented based on conservation law of fluid.(1) Almost no effects of end plates at the leading edges of semi-elliptic plan form WIG are observed for suppressing out-flowing there, but increasing normal force.(2) Fitting of about 30% length of end plates to the overall from the trailing edge is optimum for increasing normal force.