1988 Fiscal Year Final Research Report Summary
The Effects of Deck Wetting on Capsize of Ships
| Project/Area Number |
62550324
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
船舶抵抗・運動性能・計画
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| Research Institution | Kyushu University |
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Principal Investigator |
KOTERAYAMA Wataru Kyushu University, 応用力学研究所, 教授 (80038562)
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| Co-Investigator(Kenkyū-buntansha) |
KYOZUKA Yusaku Kyushu University, 応用力学研究所, 助教授 (80177948)
KASHIWAGI Masashi Kyushu University, 応用力学研究所, 助教授 (00161026)
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| Project Period (FY) |
1987 – 1988
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| Keywords | Deck wetness / Ship motion / Capsize / Following oblique waves / 画像表示 |
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| Research Abstract |
In order to know the ship's behaviour in waves under the influence of deck wetness and resultant shipping water, it is not sufficient to predict whether the deck wetness occurs or not. it is crucial to know how much amount of water flows into on deck. Moreover we need to predict how the shipping water due to the deck wetness changes the ship motions to lead to the fatal stage of capsize.
In this project, firstly we confirmed that the theoretical prediction of critical wave height of deck wetness agrees quite well with experiments. Secondly, adopting a simple formula for the velocity of water flowing into on deck, we proposed an empirical method of calculating the amount of shipping water. The effect of these shipping water was incorporated in a simplified manner into the equations of ship motions in beam seas. The motion equations adopted in this project are not rigorous, when describing the transient phenomena of deck wetness and the effect of dynamic motion of shipping water. llowever we confirmed that the proposed simulation method describes well the behaviour of ship model observed in experiments, from the start of deck wethness to the capsize or to the suppression of deck wethness.
Furthermore we developed a computer program to display the simulation results as the animation on the picture of computer graphic. This makes it easy to understand the overall phenomena of ship's capsize, and thus may provide various information useful for the investigation of safety of a ship.
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