Variable area plug nozzle
AssigneeThe NORDAM Group, Inc.
InventorJean-Pierre Lair
Life of this patent
Estimating the term…
Abstract
A center plug is configured for variable area use in an exhaust nozzle. A forward portion of the plug includes an inlet having a closing flap therein, and an aft portion of the plug includes an outlet. The flap is selectively open during aircraft takeoff operation and up to a preset climb altitude for bypassing a portion of core exhaust flow through the plug, with the flap being closed from preset altitude and cruise operation. Opening the flap correspondingly increases the available flow area for discharging the exhaust flow for reducing velocity thereof, and attenuating noise.
Claims20
A gas turbine exhaust nozzle comprising:
- an outer shell having a trailing edge;
- a plug disposed coaxially inside said shell for defining an annular exhaust duct therebetween, and extending forward from said shell trailing edge to define an annular duct inlet for receiving exhaust gases, and extending aft from said trailing edge to define an annular duct outlet therebetween for discharging said exhaust gases;
- said plug including an inlet adjacent said duct inlet, a flap closing said plug inlet, and an outlet adjacent said duct outlet;
- and
- means for selectively moving said flap to bypass a portion of said exhaust gases from said exhaust duct and through said plug to said plug outlet for discharge near said duct outlet.
A gas turbine engine exhaust plug comprising:
- an annular outer skin including an annular hump, a portion extending forward therefrom, and a portion converging aft from said hump;
- an annular inner skin disposed concentrically inside said outer skin to define an annular bypass duct radially therebetween;
- a row of plug inlet apertures disposed in said forward portion of said outer skin in flow communication with said bypass duct;
- a plug outlet disposed in said aft portion of said outer skin in flow communication with said bypass duct;
- a plurality of flaps, each disposed in a respective one of said inlet apertures;
- and
- means for selectively moving said flaps between closed and open positions for selectively bypassing exhaust gases through said bypass duct around said hump.
A method of attenuating noise in an aircraft gas turbine engine exhaust nozzle having a center plug, comprising:
- bypassing a portion of exhaust gas flow through said center plug during takeoff operation of said nozzle in an aircraft;
- and
- terminating exhaust gas bypassing through said center plug during cruise operation of said nozzle in said aircraft.
Dependencies are inferred from the claim text.