| 摘要 |
A two-dimensional variable area convergent/divergent exhaust nozzle having the capability for wide throat area variation includes upper and lower spaced apart flap means. The upper flap means comprises an upstream converging flap having its rear edge hinged to the forward edge of a downstream diverging flap, wherein the nozzle is movable between maximum and minimum throat area positions by actuation means which includes guide means, such as cam tracks, for guiding the forward edge of the upstream flap to move downstream while simultaneously constraining both the upper flap means hinge joint and the rear edge of the diverging flap to move both downstream and closer to the engine axis. This type of motion permits large changes in throat area with minimal increase in the slope of the diverging flap permitting use of a shorter diverging flap. Preferably the forward and rearward edge of the converging flap move along circular arcs having the same center in order to minimize moments on the flap.
|
