著者
松田 秋彦 梅田 直哉 鈴木 四郎
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.227, pp.47-55, 1997-03-25
被引用文献数
7

Heave and pitch motions of a ship model running in following and quartering seas with zero and very low encounter frequency were measured in a seakeeping and manoeuvring basin. Considering that 2D added mass tends to infinity at zero encounter frequency, new formulae to evaluate heave and pitch motions at zero encounter frequency were presented as a limit of a solution set of a strip theory. By comparison of the experiment and some theoretical predictions, it was concluded that, when the ship meets danger for capsizing in following and quartering seas, heave and pitch motions can be approximated by simply tracing their static equilibria. The prediction as the limit of the solution set of the strip theory at zero encounter frequency shows better agreements with the experimental values than the prediction based on the Froude-Krylov assumption. Further, up to the steepness 1/10 the heave and pitch motion with very low encounter frequency can be regarded as linear with respect of wave steepness.
著者
濱田 鉅
出版者
公益社団法人日本船舶海洋工学会
雑誌
造船協會會報 (ISSN:05148499)
巻号頁・発行日
no.69, pp.141-154, 1942-07-20

Here it is described two problems on the launching. The first relates to the geometry of the launching arrangement, and a method of calculation of the ship's draught during launching, etc. The second introduces an apparatus recording the compression of the crushing soft wood of the fore poppet during launching, with an actual record as example.
著者
加藤 洋治 山口 一 岡田 真三 菊池 浩平 宮永 大
出版者
公益社団法人日本船舶海洋工学会
雑誌
日本造船学会論文集 (ISSN:05148499)
巻号頁・発行日
no.150, pp.140-147, 1981-12

It is well-known that sheet cavitation inception is dependent on laminar separation. There-fore, the sheet cavitation might be controlled by restraining the separation. Authors tried to control sheet cavitation on an axisymmetric body by water jet injection, and proved experimentally that it was possible to suppress the sheet cavity. The nondimensional injection flow rate for the cavity suppression depended only on Reynolds number. The leading edge of the sheet cavity coincided with separation point which was visualized by oil film method. By increasing injection rate the reattachment point of separation bubble moved upstream and finally the separation bubble vanished. The sheet cavitation also vanished at the same condition.
著者
T.Z.K.
出版者
公益社団法人日本船舶海洋工学会
雑誌
造船協会雑纂 (ISSN:03861597)
巻号頁・発行日
no.192, pp.139-141, 1938-03
著者
眞田 有吾
出版者
公益社団法人日本船舶海洋工学会
雑誌
咸臨 : 日本船舶海洋工学会誌 (ISSN:18803725)
巻号頁・発行日
no.21, 2008-11-10

大阪大学では「海の日」が制定された平成8年から,船舶海洋試験水槽と関連施設の一般公開を毎年実施しており,今年で13回目を迎えた。この催しは,船舶海洋試験水槽を中心として,風洞などの関連施設の公開,体験授業などで構成されている。収容人数の関係から事前申し込み制としており,近隣小学校の小学四年生以上の児童と保護者を対象として毎年200名余りの参加をいただいている。海や船について親しんでもらうことにくわえ,親子で科学に気軽に接し,親しみをもってもらいたいとの意図から内容を構成している。家庭用ゲーム機やCGなどの発達に伴い,今の子供たちはそれらに接する機会は多いが,この催しでは参加者に手を動かしてもらい,実際の現象を自分の目と肌で感じとってもらうことを中心に据えている。以下にこの数年の実施内容を紹介する。
著者
A.T.
出版者
公益社団法人日本船舶海洋工学会
雑誌
造船協会雑纂 (ISSN:03861597)
巻号頁・発行日
no.187, pp.671-672, 1937-10
著者
高木 健 内藤 林
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.220, pp.111-120, 1993-09-25
被引用文献数
6

In order to investigate the mutual relation between the above water hull form and deck wetness, experiments are carried out with three models of which above water hull forms are different. Measurements of heave motion, pitch motion and the vertical acceleration at F.P. are performed in regular head waves and the wave steepness is varied. The behavior of the free water on the deck is recorded with a video camera. Measurements of absolute bow motion, relative bow motion and deck wetness in irregular waves are also performed. Results show followings. The effect of the above water hull form on the motion and the acceleration is small. The difference on deck wetness performace is not obvios, however the behavior of free water varies with the above water hull form. The long time experiment is needed to confirm the statistical property of deck wetness in irregular waves.