An acoustic cavity tailored synthetic jet employs a body having a cavity with a wall including a taper from a first extent to an aperture. The cavity is configured to produce a matched acoustic resonance. A drive system has a piston engaged to the cavity at the first extent. The drive system and piston are configured for oscillatory motion inducing a synthetic jet at the aperture.

An acoustic cavity tailored synthetic jet employs a body having a cavity with a wall including a taper from a first extent to an aperture. The cavity is configured to produce a matched acoustic resonance. A drive system has a piston engaged to the cavity at the first extent. The drive system and piston are configured for oscillatory motion inducing a synthetic jet at the aperture.

A fan nacelle, a gas turbine engine cell assembly, and an aircraft are provided. The fan nacelle includes a fan duct skin arranged in a fan duct to direct airflow from the fan of a Turbofan engine toward a fan nozzle. An exterior skin of the fan nacelle directs air flow around an exterior of the engine. The fan duct skin and the exterior skin terminate at a trailing edge, and a trailing edge portion of the exterior skin is one of parallel to and diverging from a trailing edge portion of the fan duct skin in an aft direction. In certain aspects, the trailing edge portion of the exterior skin is actuatable or inflatable to selectively divert from the trailing edge portion of the fan duct skin.

A fan nacelle, a gas turbine engine cell assembly, and an aircraft are provided. The fan nacelle includes a fan duct skin arranged in a fan duct to direct airflow from the fan of a Turbofan engine toward a fan nozzle. An exterior skin of the fan nacelle directs air flow around an exterior of the engine. The fan duct skin and the exterior skin terminate at a trailing edge, and a trailing edge portion of the exterior skin is one of parallel to and diverging from a trailing edge portion of the fan duct skin in an aft direction. In certain aspects, the trailing edge portion of the exterior skin is actuatable or inflatable to selectively divert from the trailing edge portion of the fan duct skin.

Methods and apparatus for sealing variable area fan nozzles of jet engines are disclosed. An apparatus in accordance with the teachings of this disclosure includes a frame and a seal to be coupled to the frame. The seal to enclose petals of a variable area fan nozzle to substantially prevent airflow between the petals.

Methods and apparatus for sealing variable area fan nozzles of jet engines are disclosed. An apparatus in accordance with the teachings of this disclosure includes a frame and a seal to be coupled to the frame. The seal to enclose petals of a variable area fan nozzle to substantially prevent airflow between the petals.

A propulsion system coupled to a vehicle. The system includes a diffusing structure and a conduit portion configured to introduce to the diffusing structure through a passage a primary fluid produced by the vehicle. The passage is defined by a wall, and the diffusing structure comprises a terminal end configured to provide egress from the system for the introduced primary fluid. A constricting element is disposed adjacent the wall. An actuating apparatus is coupled to the constricting element and is configured to urge the constricting element toward the wall, thereby reducing the cross-sectional area of the passage.

A propulsion system coupled to a vehicle. The system includes a diffusing structure and a conduit portion configured to introduce to the diffusing structure through a passage a primary fluid produced by the vehicle. The passage is defined by a wall, and the diffusing structure comprises a terminal end configured to provide egress from the system for the introduced primary fluid. A constricting element is disposed adjacent the wall. An actuating apparatus is coupled to the constricting element and is configured to urge the constricting element toward the wall, thereby reducing the cross-sectional area of the passage.

A turbofan engine includes a fan section. A core engine section drives the fan section. An outer nacelle surrounds the fan section and defines a radially outer surface of a fan duct. An inner nacelle surrounds the core engine section and defines a radially inner surface of the fan duct. A nozzle is disposed at a terminal end of the outer nacelle that defines an exit area for bypass air flow through the fan duct. The nozzle includes a convergent portion forward of a divergent portion and a turning angle for the divergent portion greater than about 12 degrees. A nacelle assembly and method are also disclosed.

A system for a thrust reverser of an aircraft includes a primary sleeve and a secondary sleeve having cascades. The secondary sleeve is coupled to a set of blocker doors. The sliding motions of the primary sleeve and the secondary sleeve are not directly coupled when each moves between its stowed and deployed positions. The sliding motion of the primary sleeve may begin at a different time and continue at a different rate from the sliding motion of the secondary sleeve.