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船舶薄层气膜减阻技术的试验和应用 总被引:7,自引:0,他引:7
作者自1982年起研究薄层气膜形成规律和船舶薄层气膜减阻技术,利用该技术能有效形成船底薄层空气膜,使船舶减阻15~30%「1,2」。本文介绍了船舶薄层气膜减阻技术的模型试验研究和1000t甲板驳应用薄层气膜技术的实船试验结果「3」。 相似文献
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Kazuhiro Fukuda Junichiro Tokunaga Takashi Nobunaga Tatsuo Nakatani Toru Iwasaki Yoshikuni Kunitake 《Journal of Marine Science and Technology》2000,5(3):123-130
This paper presents a new technique for reducing frictional drag using a super-water-repellent surface and air-injection
(called an SWR & A technique). Its effectiveness was examined by carrying out pressure-loss measurements with a tube of rectangular
cross section, along with resistance tests on a horizontal flat plate, a 7.2-m-long tanker model, and a 12-m-long high length-to-beam-ratio
model ship. These test results showed that the new technique can significantly reduce the models' frictional drag; for example,
the frictional resistance on the SWR surface was reduced by 80% at a speed of 4 m/s and 55% at 8 m/s.
Received: October 16, 2000 / Accepted: December 4, 2000 相似文献
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In the present paper, a new trimaran Pure Car Carrier (PCC) is proposed and a feasibility study on the ship is carried out.
In this study, first, the effective horse power (EHP)/car of the PCC running in still water is predicted. By comparing the
predicted EHP/car with that of a conventional mono-hull PCC, it is found that the trimaran PCC is superior to the conventional
mono-hull PCC at rather higher speed. As ship speed increases, the reduction of the resistance of the trimaran is bigger.
It is also found that at common service speed of PCCs, the EHP/car of a small PCC is lower than that of a conventional PCC.
Secondly, the optimal L/B of a main-hull of the trimaran PCC in still water is determined. The optimal L/B of the main-hull varies with ship speed and size because the wave resistance decreases but the frictional resistance increases
as L/B of the hull increases. As ship size increases, the optimal L/B of the main-hull of the trimaran PCC decreases. 相似文献
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