| 摘要 |
<p>Some embodiments relate to a propeller having a hub and a plurality of radially extending blades, wherein a radial extreme of each of the blades is integral with an end plate defining a ring segment coaxial with the propeller hub, each ring segment having 5 a concave inner surface and conforming generally to a frustoconical ring, the radial cross section of which is angled at between 0' and 150 to an axis of rotation of the propeller. I,?</p> |
