Semi-Submerged Ship Form with Minimum Wave Making Resistance

Abstract

In the previous paper, as a high speed displacement type hull form the author introduced a semi -submerged ship with the minimum wave making resistance being composed of the combination of source distribution, thus consisting of the submerged hull of the Rankine's ovoid and the upper slender body having sectional area of Versine distribution.In this paper, it is attempted to describe the above hull form in a more general manner and in details. There are two or three ways to minimize the wave making resistance of the subject hull form under the arbitrary condition, but there is found not so notable difference between the respective results obtained therefrom in so far as within the practical speed ranges of this hull form theory. Assuming that the sum of theoretical wave making resistance and surface frictional resistance of this hull form to be the total resistance, and when it is tried to seek the hull form with the minimum total resistance, it should come to a semi-submerged ship for delivery at high designed speed range. While on the other hand, when the designed speed is low, the hull form will rather tend to be a general surface ship with a bulbous bow in a ram shape, thereby permitting to secure the lateral stability, thus it is enabled to make the application of this hull form for general vessels.