초록 ▼

A noise reduction kit for modifying a two (2) spool axial flow turbofan engine with multi-stage compressors and fan driven by multi-stage reaction turbines, and a thrust of at least about 18,000 lbs. at sea level. There is a fan at the upstream end of the core engine for generating axial fan air flo

A noise reduction kit for modifying a two (2) spool axial flow turbofan engine with multi-stage compressors and fan driven by multi-stage reaction turbines, and a thrust of at least about 18,000 lbs. at sea level. There is a fan at the upstream end of the core engine for generating axial fan air flow through bypass ducts terminating at a common nozzle, the common nozzle having a mixing plane area for each of the fan air flow and for the exhaust gas in a range between 700 and 800 square inches. A target thrust reverser includes opposing doors rotatable into position to block and divert the flow of exhaust gas for generating reverse thrust. Mixing means for radially diverting fan air and permitting radially outward expansion of exhaust gas is provided coaxially downstream to the core engine. An acoustically dampened light bulb-shaped nose cone is provided for coaxial attachment to an upstream end of the core engine. The axial flow front fan is axially separated from the inlet guide vane is extended relatively forwardly. A bleed air valve, selectively operational to bleed air from the core engine when the valve is open, is ducted for directing bleed air to the vicinity of the common nozzle.

대표청구항 ▼

[ What is claimed is:] [1.] A noise reduction kit for modifying a two spool axial flow turbofan engine with multistage compressors and fan driven by multistage reaction turbines, and a thrust of at least about 18,000 lbs at sea level, including a fan at an upstream end of a core engine for generatin

[ What is claimed is:] [1.] A noise reduction kit for modifying a two spool axial flow turbofan engine with multistage compressors and fan driven by multistage reaction turbines, and a thrust of at least about 18,000 lbs at sea level, including a fan at an upstream end of a core engine for generating axial fan air flow through bypass ducts terminating at a common nozzle and mixer in a tail pipe assembly disposed to axially receive and exhaust the exhaust gas and fan air selectively into a thrust reverser for converting axial flow of exhaust gas and fan air into reverse thrust, or for axial flow for disposing of the exhaust gas and fan air, the kit comprising:a) the mixer having an upstream end and an annular mixer wall axially extending downstream therefrom the wall being formed into a plurality of circumferentially alternating radially inward and radially outward lobes, the radially inward lobes defining cold chutes for radially inwardly diverting fan air and outward lobes defining hot chutes for permitting radially outward expansion of exhaust gas such that the common nozzle has a mixing plane area for each of the fan air flow and for the exhaust gas in a range between 700 and 800 square inches;b) an annular mixer adapter for fixing the mixer to the engine casing in a position downstream of and coaxial with the core engine;c) a mixer transition contour plate having an upstream end portion for coaxial attachment to the downstream end of the core engine and having an annular, axially extending transition contour plate portion for attachment to the upstream end of the mixer, the plate being shaped to aerodynamically conform to the mixer to direct fan air; andd) an annular transition duct 60 for axial disposition between the downstream end of the core engine and a thrust reverser, the duct 60 extending an axial flow path of mixed exhaust gas and fan air downstream of the mixer.