Duct pressure actuated nozzle

摘要

A variable area nozzle which utilizes high pressure duct nozzle air directly to actuate a variable area nozzle and thereby control the nozzle throat area. A servo controlled air valve directs the duct air pressure into a pressure cavity causing the nozzle to move toward the closed position while the nozzle entrance pressure acting on the converging flaps urges the nozzle to move toward the open position while the pressure cavity is exhausted to ambient through the air valve. Thus, the need for mechanical and/or hydraulic drives with the associated cooling requirements to produce variations of the nozzle configuration are effectively eliminated.