著者

黒田 貴子 原 正一 松田 秋彦

出版者

公益社団法人 日本船舶海洋工学会

雑誌

日本船舶海洋工学会論文集 (ISSN:18803717)

巻号頁・発行日

vol.6, pp.339-345, 2007 (Released:2008-03-18)

参考文献数

8

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In order to make a plan of ship towing, it is necessary to investigate the towing performance of the tow ship, status of the towed ship, external force acting on the towed ship and sea conditions. The factors of the towing performance are derived from the towing gear and main engine power, which are evaluated by the bollard pull test in the case of the tugboat. When the general ship instead of the tugboat makes a towing operation, the towing performance with the main engine power is crucial. It is important to know the towing performance of the tow ship and tow force depending on the size of towed ships in several sea states in the emergency towing by the general ship.The bollard pull test and towing test in calm and rough seas have been carried out to investigate the tow force and tow power, critical tow force and the condition of safe towing. The towing safety factor is defined by the critical tow force divided by the maximum towline tension during towing. The factor less than 1 indicates the disability of towing. The critical condition is shown by the value between 1 and 2. Lastly its value larger than 2 indicates the safe towing. The towline tension is calculated by the Optimum Towing Support System developed by the National Maritime Research Institute. In this calculation, the patrol vessel as tow ship tows 5kinds of ships in several sea states. By using the ratio of critical tow force and calculated towline tension, the towing safety factor is estimated and the chart for the critical towing performance in several sea states using the displacement ratio between tow and towed ship has been shown. Even the operator of the general ship will be able to know the possibility of the safe emergency towing using the displacement of the towed ship in certain weather condition in this chart.

著者

黒田 貴子 原 正一 松田 秋彦

出版者

公益社団法人 日本船舶海洋工学会

雑誌

日本船舶海洋工学会講演会論文集 5E (ISSN:24241628)

巻号頁・発行日

pp.121-122, 2007 (Released:2017-12-28)

著者

松田 秋彦 橋本 博公 谷口 裕樹 寺田 大介 三好 潤 溝口 弘泰 長谷川 勝男 世良 亘

出版者

海洋理工学会

雑誌

海洋理工学会誌 (ISSN:13412752)

巻号頁・発行日

vol.23, no.1, pp.47-51, 2017 (Released:2017-07-07)

参考文献数

12

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As seaborne trade has greatly increased in recent years, it becomes more difficult to secure crew of ships. Therefore, it is an important issue how to realize unmanned robot ships which can automatically navigate without collisions even in congested waters. Although Rolls-Royce is planning to build a remotely controlled ship in 2020, standard control technology for unmanned ships has not been developed yet. Therefore an automatic collision avoidance system is discussed by carrying out not only computer simulations but also model experiments prior to the tests using actual vessels. For this purpose, the authors built an experimental system for the validation of automatic collision avoidance algorithm. In this paper, model experiments using multiple ships conducted at Marine Dynamics Basin at National Research Institute of Fisheries Engineering are introduced. Through comparisons with numerical simulations which the same algorithm for collision avoidance is implemented, it is found that there is a discrepancy in occurrence of collision in extremely congested situation.

著者

斎藤 公男 肥後 靖 高木 幹雄 小瀬 邦治 松田 秋彦 梅田 直也 小寺山 亘 今井 康貴

出版者

広島大学

雑誌

基盤研究(B)

巻号頁・発行日

2000

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沿岸海域を航行する中小型船を対象とし,模型船による波浪中実験や鋼材運搬用内航貨物船の運航性能に関する実態調査を実施し,それらの解析結果より以下の知見を得た。1)船体応答から波浪情報を推定する簡易推定法を提案し,波高計アレイ実験結果と比較したところ,有義波高,平均波周期及び波の主方向に関して,多少のばらつきがあるものの,十分な精度のあることが確認できた。2)上記簡易推定法を模型船曳航実験により得られた推定値と計測値を比較したところ,平均波周期については,全体的によい結果が得られたが,有義波高については追波状態に差がみられた。波の主方向については,30°以内で考えると70〜80%の精度が得られた。3)鋼材運搬用内航貨物船「裕翔丸」(長さ76m,幅12m)に計測器を搭載し,ブリッジで計測した船体運動から船倉内の加速度が概ね推定できることがわかった。4)ハッチカバーレス内航コンテナ船の海水打ち込み水量をダム崩壊理論及び洪水流理論を組み合わせて推定し,それらを模型実験結果と比較したところ,横波中で前進速度を持たない場合においては,計算値と実験値はよく一致した。一方,前進速度がある場合には,定性的に似た傾向を持つものの定量的には理論計算の改良が必要であることがわかった。海水打ち込みの発生頻度については,定量的にも推定値と実験値は良い一致を示した。5)安全性,定時性の向上に関連し,海水打ち込みの発生頻度と運航条件(船と波の出会い角,船速)の関係について,船の運航者の手助けとなる運航状態図を作成した。

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

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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

松田 秋彦

出版者

公益社団法人日本船舶海洋工学会

雑誌

らん : 纜 (ISSN:09160981)

巻号頁・発行日

vol.37, pp.41-43, 1997-10

著者

松田 秋彦

出版者

公益社団法人日本船舶海洋工学会

雑誌

らん : 纜 (ISSN:09160981)

巻号頁・発行日

no.33, pp.70-71, 1996-09-30