著者

川島 栄一 朝倉 五郎

出版者

The Japan Society of Naval Architects and Ocean Engineers

雑誌

造船協會論文集 (ISSN:18842062)

巻号頁・発行日

vol.1954, no.95, pp.81-88, 1954 (Released:2007-05-28)

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Now defunct Japanese Navy prescribed, at its designing of war crafts, in consideration of their stability capacity, the permissible lowest values of GM, OG, Stability range, etc. separately, in accordance with the class of vessels and their sizes.Later on, however, due to the development of stability theory, it became possible to determine the stability capacity, by applying the organic relation of these values mentioned above and obtaining a value that is the combination of these values.In this thesis the authors, basing upon the“Theory of Safety Criterion of a Ship”established by Prof. Watanabe, have calculated the Safety Criterion c Value, studying the actual instances of 15 vessels, including destroyers and torpedo boats of the defunct Japanese Navy, and about 90 of their different conditions and analysed them from various angle, such as the transition of the history, and the statistic distributional state.This study of the authors has led to the possibility to determine the permissible lowest value of safety criterion of naval small crafts.

著者

川島 栄一 坂尾 稔 田崎 亮

出版者

The Japan Society of Naval Architects and Ocean Engineers

雑誌

造船協會論文集 (ISSN:18842062)

巻号頁・発行日

vol.1959, no.105, pp.93-107, 1959 (Released:2009-09-16)

参考文献数

6

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The nuclear power plant for ship must be able to endure sufficently to the severe ship motion in rough sea. Therefore, in the design of reactor, we must predict the magnitude of acceleration_ or inertia force acting on it. In this paper, we attempted to the statistical considerations on the vertical acceleration due to the pitching and heaving, and some consideration of rolling acceleration. They are as follows.1. From the response amplitude operator of vertical acceleration that is measured at model experiment in regular wave and Neumann's spectrum of sea wave, we calculated the statistical magnitude of vertical acceleration of small fine ship, high speed cargo liner, and large oil tanker for various ship speed and wind velocity.2. From the above data, under the following condition, we obtained the values shown in Table 4 which was regarded as the reasonable values of vertical acceleration to use in the design of reactor part of various nuclear ship.a) As the ship speed, we adopted the maximum mean speed obtained from the point of view of resistance increase only.b) As the sea condition, we adopted the fully developed sea for wind velocity U=20 m/s.c) As the statistical magnitude of acceleration, we adopted the maximum acceleration a0, which is the vertical acceleration that the probability which maximum vertical acceleration in 5, 000 continuous waves exceeds a0 is 10%.3. The rolling acceleration at resonant condition are expressed by Ts·√g/B only approximately such as Fig. 17.The magnitude of rolling acceleration is smaller than that of vertical acceleration by pitching and heaving, but it must be careful because of the difference of its direction.