| 摘要 |
An aircraft propulsion assembly in which a prime mover drives a rotating air stream generating element, situated in a generally circular housing that supports a ring shaped stator in which a number of circumferentially spaced slots are defined. An elongate nozzle is axially aligned with the rotating element, which nozzle on the forward end in cooperation with the housing defines a circular plenum chamber that is in communication with the slots. The plenum chamber on an inner portion thereof cooperates with the stator to define a circular aperture. A first portion of the air stream generated by the rotating element flows rearwardly through the nozzle and a second portion through the slots in to the plenum chamber to be compressed. The compressed air excapes from the plenum chamber through the circular aperture, and due to the Coanda effect flows along the interior surface of the nozzle as a cylindrical sheath at a higher velocity than the first portion of the air stream flowing rearwardly through the nozzle. As a result, the first portion of the air stream is not subjected to any appreciable drag resistance and exits from the nozzle at maximum velocity to impart maximum forward thrust to the assembly.
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