Now, though, a combination of factors — ranging from advances in computer numerical control (CNC) machining and modeling software to plain old ingenuity — have been speeding developments for propellers as well as for their stablemate, the unglamorous rudder.
A particularly interesting innovation in propulsion recently emerged from U.S.-based Sharrow Marine, which offers a new propeller technology that so far has been adopted primarily in the recreational market, but also should find a ready place aboard workboats, ferries and other commercial vessels.
The design was invented by Gregory Sharrow and subsequently developed by Sharrow Engineering LLC in Philadelphia. According to the company, 46 international patents have been filed related to the design, and 24 patents have been awarded in the United States, Japan, Canada, Australia, Europe (14 countries), Taiwan, China, and South Korea.
A key claim in the U.S. patent abstract is that the Sharrow propeller has “a means for creating fluid flow in a non-axial direction and redirecting it in an axial direction.” In other words, the centrifugal flow created as a byproduct of creating thrust is largely captured and redirected by employing the Sharrow design, which uses blades that resemble a slightly twisted loop rather than a curved paddle. That unique shape helps explain the company’s claims of improved performance and efficiency.
Translating tech gains into savings
To tap the full savings potential of improved propellers and rudders, you need advanced and flexible components farther up the drive train, especially in an era of evolving power sources.
この記事は Professional Mariner の December - January2021 版に掲載されています。
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この記事は Professional Mariner の December - January2021 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、9,000 以上の雑誌や新聞にアクセスしてください。
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