초록 ▼

A method is disclosed for discharging combustion gases from an engine powering an aircraft at subsonic and supersonic velocities. The engine includes a variable area exhaust nozzle having primary and secondary flaps defining a generally converging channel and exhaust channel, respectively, for the c

A method is disclosed for discharging combustion gases from an engine powering an aircraft at subsonic and supersonic velocities. The engine includes a variable area exhaust nozzle having primary and secondary flaps defining a generally converging channel and exhaust channel, respectively, for the combustion gases. The method comprises the steps of contouring the secondary flaps to a first contour at a first position at a first value of a nozzle pressure ratio NPR across the converging and exhaust channels. The method further includes the step of contouring the secondary flaps to a second contour at a second position at a second value of NPR. In a preferred embodiment, the first contour is straight at low values of NPR and the second contour is generally concave for high values of NPR. Preferred embodiments of an exhaust nozzle for carrying out the method include the secondary flaps taking the form of a plurality of articulated secondary flap segments which are positionable collectively to form a straight contour of low NPR values and to form a generally concave contour at relatively high NPR values.

대표청구항 ▼

A method for discharging combustion gases from an engine powering an aircraft at subsonic and supersonic velocities, said engine including an exhaust nozzle having primary flaps defining a generally converging channel for channeling said combustion gases, and secondary flaps extending downstream fro

A method for discharging combustion gases from an engine powering an aircraft at subsonic and supersonic velocities, said engine including an exhaust nozzle having primary flaps defining a generally converging channel for channeling said combustion gases, and secondary flaps extending downstream from said primary flaps in flow communication therewith and defining an exhaust channel having an outlet for discharging said combustion gases from said nozzle, the method comprising the steps of: contouring said secondary flaps to a first contour at a first position for discharging said combustion gases through said exhaust channel at a first value of a nozzle pressure ratio NPR defined across said converging and exhaust channels; and contouring said secondary flaps to a second contour at a second position for discharging said combustion gases through said exhaust channel at a second value of said NPR, said second contour, said second position, and said second NPR value being different than said first contour, said first position, and said first NPR value, respectively.