碩士 / 國立中興大學 / 機械工程學系所 / 96 / Even today academia has not yet been able to grasp the essence of dolphin propulsion strategy. After a 65 million years the cetaceans category evolved a high aspect ratio, light, thin/high tail fin for pushing a large amount of water backward with a small velocity difference in order to achieve a high propulsion efficiency. With streamlined body and muscles as power source basis for propulsion, dolphin can swim up to a maximum speed of about 50 km/hour. Herein we will present the innovative concepts of "kidnapped airfoils" and "circulating horsepower" to illustrate how the high-speed dolphins swim forward with body and tail working like two deformable airfoils tightly linked to utilize their lift forces for each other cleverly to form a "kidnapped airfoils" phenomenon and capture body lift power to compensate most of the body drag power. In this manner the dolphin can greatly enhance its propulsion efficiency to easily exceed 400% or even more, meanwhile it solves the long-plagued perplexity of Gray paradox lasting for more than 70 years.
| Identifer | oai:union.ndltd.org:TW/096NCHU5311029 |
| Date | January 2008 |
| Creators | Yi-Shu Li, 李易樹 |
| Contributors | 李興軍 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 54 |
Page generated in 0.0105 seconds