Abstract: A jet engine assembly having a jet engine and an unsteady flow ejector. The unsteady flow ejector segregates the exhaust flow from the jet engine into a plurality of rotating high velocity, low density jets and a plurality of rotating low pressure voids. The low pressure voids are employed to entrain at least a portion of a secondary flow of air which is mixed with the jets to produce a mixed flow having a relatively higher flow rate and a relatively lower velocity than the exhaust flow. A method for attenuating the noise that is produced by the exhaust flow of a jet engine is also provided.

Abstract: A jet engine assembly having a jet engine and an unsteady flow ejector. The unsteady flow ejector segregates the exhaust flow from the jet engine into a plurality of rotating high velocity, low density jets and a plurality of rotating low pressure voids. The low pressure voids are employed to entrain at least a portion of a secondary flow of air which is mixed with the jets to produce a mixed flow having a relatively higher flow rate and a relatively lower velocity than the exhaust flow. A method for attenuating the noise that is produced by the exhaust flow of a jet engine is also provided.

Abstract: An ejector nozzle (10) including an first cowling (12), a second cowling (14), and opposed upright sidewalls (16) that together form an internal nozzle exhaust path is provided. A reconfigurable plug assembly (18) having separable first and second diverters (20), (22) is located in the exhaust path to direct engine exhaust (24) in either dual paths formed around diverter outer surfaces (76), or dual paths formed between the diverter inner surfaces (74) and centerbody exterior surfaces. When the diverters direct exhaust airflow between themselves, first and second ejectors (26), (28) formed in the first and second cowlings (12), (14), respectively, are available to entrain ambient air (30) into the exhaust stream (24). The preferred ejectors include translatable aft flaps (32), (34). Mixing devices, such as a lobed mixer (90) are incorporated into the diverters (20), (22) to improve engine noise suppression.

Abstract: A moderately high bypass ratio turbofan engine nozzle (36) is provided including an outer structure (46) and one or more ejectors (38). The ejectors (38) include inner and outer doors (82), (80) for closing off an ejector passage (76) extending through the outer structure (46). The ejectors (38) are sized to entrain exterior air (40) at aspiration ratios of generally less than 60%. The exterior air (40) is mixed with engine exhaust (42), resulting in a lower combined airflow velocity which in turn reduces jet exhaust noise. Mixing components formed as turning vanes (108) are located in the ejector passage (76) for encouraging further mixing of the airflows (40), (42). In preferred embodiments, the nozzle (36) further includes a translatable centerbody (52), an aft flap assembly (112), and a control system (122) for controlling the movements of the nozzle components.

Abstract: An aircraft ejector nozzle includes a plug assembly (26) located between upper and lower cowlings (18, 20) and upright sidewalls (22). The plug assembly (26) includes separable upper and lower diverters (28, 30). Each diverter includes multiple subsections pivotably attached end-to-end. In one embodiment, first, second, and third subsections (90, 92, 94) are provided. Stationary ejectors (40, 42) located in the cowlings (18, 20) input ambient airflow (44) into an exhaust stream (32). Preferably the ejectors (40, 42) include mixing components (46). Upper and lower aft flaps (48, 50) further tailor the exhaust path shape. An actuation assembly (52) moves the diverters (28, 30) and aft flaps (48, 50) between their various positions. One actuation assembly embodiment includes a number of rotatable disks (118, 120, 132, 134, 142) for guiding the upper and lower diverters (28, 30) and the aft flaps (48, 50).

Abstract: A cooling system for a hypersonic aircraft is disclosed which enables hypersonic flight using non-cryogenic fuels. The cooling system positions a primary heat exchanger at an external location on the aircraft which remains relatively cool during hypersonic flight. A working fluid is passed through the primary heat exchanger to the hot parts of a supersonic combustion ram jet engine.

Abstract: Various aircraft flight parameters are determined based on the thermal radiation emitted from a plurality of members while the aircraft is flying. A fiberoptic cable is positioned adjacent the member emitting the thermal radiation. A thermal radiation sensor receives, through the fiberoptic cable, the radiation emitted by the member and generates an electrical signal corresponding to the radiation emitted. For an aircraft traveling at high speeds, the heat flux generated across the skin surface by air friction is proportional to the velocity and angle of attack at a given air density. An on-board computer calculates various aircraft flight parameters, such as velocity, angle of attack of various aircraft surfaces, and the like, based on the signals received from the radiation sensors. Aircraft flight parameters are more rapidly and accurately determined than possible in the prior art.

Abstract: A system for measuring aeroelastic deformation of an aircraft wing in flight or in a wind tunnel utilizing light from a linearly polarized light source (101). The light is transmitted through modulating elements (104, 105) to provide a carrier beam, and a small portion of the beam is reflected through a linear polarizer (107) into a photo-detector (108) for utilization as a reference electrical signal (208). The remainder of the beam is reflected back from a retro-reflector target (700) located on the wing into another photo-detector (114) to provide the target electrical signal (209). The two amplified electrical signals are compared in a phase detector (FIG. 3) for providing an angle measurement output signal E.sub.0.