초록 ▼

A combination convergent jet engine aircraft nozzle (86, 142, 146) and a ventilation tube (88, 136, 144) are fixed in place and have no moving parts. Ambient air is entrained through duct inlets (96, 140, 154, 160), through the nozzle walls, through hollow struts (90, 138), the struts supporting and

A combination convergent jet engine aircraft nozzle (86, 142, 146) and a ventilation tube (88, 136, 144) are fixed in place and have no moving parts. Ambient air is entrained through duct inlets (96, 140, 154, 160), through the nozzle walls, through hollow struts (90, 138), the struts supporting and being connected to a hollow central tube (102, 144) or a plurality of tubes (136), to adjacent the downstream end of the nozzle to mix at takeoff with the jet forming gas exhaust. The ducts (102, 136, 144) are positioned with respect to the nozzle exhaust so that entrained ambient air flows into the gas exhaust during takeoff and so that the ambient air flow is substantially restricted or shut off during cruise flight. Ambient air inlet openings (160) are formed as a porous surface, the holes through the surface being generally in the shape of louvers (166) of which downstream end portions (174) are depressed inwardly of the outer wall surface of the nozzle to provide a minimum drag along the outer nozzle periphery during cruise flight and at takeoff. A method of positioning and fixing the outlet end of a noise suppressor within a convergent nozzle so that entrained ambient air flows into the gas exhaust during takeoff to substantially reduce the engine noise and so that ambient air is substantially restricted or is shut off entirely during cruise flight. The method in which ambient air is entrained in a noise suppressor within a convergent nozzle and is exited downstream adjacent the nozzle downstream end to mix with the gas exhaust during takeoff to suppress the engine noise, and at cruise flight substantially restricting or shutting off the ambient air through the noise suppressor by turning engine exhaust gas toward the noise suppressor axis downstream of the ambient air exit.

대표청구항 ▼

In a convergent jet engine aircraft nozzle adapted to exhaust a propulsive gas jet, said nozzle having wall means longitudinally bounding a substantially open portion, said wall means bounding said portion converging toward a downstream exhaust end, jet engine noise suppressor means for supplying am

In a convergent jet engine aircraft nozzle adapted to exhaust a propulsive gas jet, said nozzle having wall means longitudinally bounding a substantially open portion, said wall means bounding said portion converging toward a downstream exhaust end, jet engine noise suppressor means for supplying ambient air through the inside of said nozzle so as to reduce the noise produced by said gas jet during takeoff, said suppressor means including duct means for entraining said air through said wall means, into said nozzle, and to a position associated with the nozzle downstream end to mix with the gas exhaust at takeoff, said duct means having upstream inlet and downstream outlet ends, the improvement comprising: said duct means being open upstream to entrain the ambient air during takeoff and being connected into said wall means for entraining said air during takeoff downstream out of said duct means to mix with the jet forming gas exhaust; said duct means being of substantially minimum low-drag configuration, relative to air flow therethrough and gas flow therearound, said duct means being continuously open between and at upstream and downstream ends and being fixed in shape and position, and being positioned downstream in association with the nozzle exhaust so that the entrained ambient air flows into the gas exhaust during takeoff and so that ambient air flow is substantially restricted or is shut off entirely during cruise flight. The method of suppressing jet engine noise in an aircraft by internally ventilating, with ambient air through a noise suppressor in a convergent nozzle, and substantially reducing the drag of the noise suppressor during cruise flight; said nozzle having wall means longitudinally bounding a substantially open portion, said wall means converging toward a downstream exhaust end; said noise suppressor including duct means for carrying said air through said wall means, into said nozzle, and to a position associated with the nozzle downstream end to mix with the gas exhaust at takeoff; said duct means having upstream inlet and downstream outlet ends; said method comprising: entraining ambient air into the duct means and exiting the air downstream adjacent the nozzle downstream end to mix with the gas exhaust during takeoff; and turning the engine exhaust gas toward the duct means axis downstream of the ambient air exit during cruise flight, and substantially restricting or shutting off the ambient air flow through the duct means.