| 摘要 |
PURPOSE:To enhance propelling efficiency, by a method wherein stationary blades are provided on the rear part of a duct, and the rotational energy so far has been wasted from a propeller into a flowing fluid is recovered. CONSTITUTION:The stationary blades 3 having a pitch opposite to that of the propeller 1 are provided on the rear part of the duct 2. Accordingly, part of the rotational energy in the rear part of the propeller 1 causes the stationary blades 3 to generate a propelling force, so that the propelling efficiency can be enhanced. |
