微泡減阻技術在船模上應用之研究

Study on the Application of Micro-bubble Drag Reduction Technique on Ship Model

徐維(Wei Hsu)

指導教授 ： 蔡進發

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.00789

摘要

地球暖化是近年來受到國際關注的話題，而造成地球暖化的元兇之一即是船舶燃燒石油後所排放的二氧化碳等廢氣，若要減少石油的燃燒，便須從提高能源的使用效率著手，而減少船體的阻力就是能達成此一目標的方式。
本研究以台灣國際造船股份有限公司所設計的RD542_1船模為研究對象，進行微泡減阻技術在船模上的應用實驗，本實驗設計在船模底部及側邊的平面處裝設鋁製和銅製的平板型透氣材，且在球艏、球艏後方以及平行舯體必龍骨等船體曲面處裝設撓性透氣材，以增加曲面的微泡覆蓋面積。船模實驗分為兩部分：阻力實驗及自推實驗。先以阻力實驗量測船模在水槽中拖航時的阻力，並比較有微泡時與無微泡時的阻力差異，以得知微泡減阻效果，接著再以自推實驗來觀察微泡對船艉螺槳所產生的影響，並以自推實驗的螺槳推力來驗證阻力實驗所得到的微泡減阻效果。
阻力實驗結果發現，底部透氣材的噴氣實驗在每個速度下皆有減阻效果，為較為穩定的噴氣方式，最佳減阻效果2.5%，而在自推實驗時也能得到同樣的減阻結果，並從數據中可觀察到氣泡確實對螺槳性能造成影響，因此未來須在船身後方設計機構，以避免氣泡進入到螺槳平面。

關鍵字

微泡減阻技術 ； 阻力試驗 ； 自推試驗

並列摘要

Global warming is the topic of international concern in recent years. Waste gas like carbon dioxide produced by ships is one of the reasons causes global warming. To increase the efficiency of energy usage is the way to reduce the waste gas. One of the ways to achieve this purpose is to reduce the resistance of ships for sea transportation.
The micro-bubble drag reduction technique was developed and applied to the ship model coded as RD542-1 from CSBC. The flat plate porous material and the flexible porous material were used for injecting micro bubble. There are two kinds of flat plate porous material: the aluminum made porous material and the copper made porous material. The aluminum made porous material and the copper made porous material were used at the flat bottom and the flat side of the ship model. The flexible porous material was used at the curve surface of the ship model: bulb bow, the location of station 7.5, station 8.5 and bilge keel. There were two kinds of the experiments conducted is this study which include the resistance test and the self propulsion test. Resistance test is for measuring the total resistance of the ship model. In order to get the efficiency of drag reduction, the resistance of ship model with bubble injecting was compared to the resistance without bubble injecting. Self propulsion test is conducted for evaluating the influence of propeller and confirming the drag reduction effect.
2.5% frictional drag reduction is got for the micro-bubble injecting at the flat bottom in resistance test results. The result of self propulsion test is the same as the result from the resistance test. Injecting at the flat bottom is a steady way for the drag reduction because it works in each speed. According to the experiment results, the micro bubble would affect the propeller performance when injecting the bubbles at the flat bottom. Therefore, there should have a mechanism in front of the propeller to avoid the micro bubbles flowing into the propeller plane in future research.

並列關鍵字

Micro-bubble drag reduction technique ； ship resistance test ； self propulsion test

參考文獻

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