Control scheme using variable area turbine and exhaust nozzle to reduce drag

Patent metadata

Field	Value
Publication number	US-9822731-B2
Application number	US-201514671158-A
Country	US
Kind code	B2
Filing date	Mar 27, 2015
Priority date	Mar 27, 2015
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

A method to reduce aerodynamic drag of a engine exhaust/engine nozzle includes collecting data that is indicative of an instant flight condition, entering the data into a decision algorithm that, based on the data, outputs at least first and second drag control parameters corresponding, respectively, to an angle of one or more variable area turbines of a turbine engine and a position of a variable area exhaust nozzle of the turbine engine, and adjusting the angle of the one or more variable area turbines and the position of the variable area exhaust nozzle according to, respectively, the first and second drag control parameters to reduce aerodynamic drag of an engine exhaust/engine nozzle of the turbine engine.

First claim

What is claimed is:

1. A method to reduce aerodynamic drag of an engine exhaust or nozzle, the method comprising:
collecting data that is indicative of an instant flight condition;
entering the data into a decision algorithm that, based on the data, outputs first and second drag control parameters corresponding, respectively, to an angle of one or more variable area turbines of a turbine engine and a position of a variable area exhaust nozzle of the turbine engine, and the decision algorithm also outputs a third drag control parameter corresponding to a fuel flow ratio between fuel flow to a combustor of the turbine engine and fuel flow to an augmentor of the turbine engine; and
adjusting the angle of the one or more variable area turbines and the position of the variable area exhaust nozzle according to, respectively, the first and second drag control parameters to reduce aerodynamic drag of an engine exhaust or nozzle of the turbine engine, and adjusting total fuel flow and the fuel flow ratio in accordance with the third drag control parameter to reduce the aerodynamic drag of the engine exhaust and nozzle.

2. The method as recited in claim 1 , wherein the data is selected from the group consisting of altitude, ambient air pressure, Mach number, throttle level, ambient air temperature, humidity, aircraft angle of attack and rate of climb, and combinations thereof.

3. The method as recited in claim 1 , wherein the decision algorithm also outputs a fourth drag control parameter corresponding to an engine exhaust nozzle pressure ratio of the turbine engine, and adjusting the exhaust nozzle pressure ratio in accordance with the fourth drag control parameter to reduce the aerodynamic drag.

4. The method as recited in claim 1 , wherein the adjusting of the angle and the position result in a controlled change of pressure in the variable area exhaust nozzle to reduce aerodynamic drag of the engine exhaust or nozzle.

5. The method as recited in claim 1 , wherein the adjusting of the angle and the position result in a controlled change of temperature in the variable area exhaust nozzle to reduce aerodynamic drag of the engine exhaust or nozzle.

6. The method as recited in claim 1 , wherein the adjusting of the angle and the position result in a controlled change of temperature and pressure in the variable area exhaust nozzle to reduce aerodynamic drag of the engine exhaust or nozzle.

7. The method as recited in claim 1 , wherein the one or more variable area turbines includes a first variable area turbine in a low-pressure turbine section and a second variable area turbine in a high-pressure turbine section.

8. The method as recited in claim 1 , wherein the data includes i) engine data selected from the group consisting of engine pressure ratio, shaft rotational speed, positions of variable vanes, and combinations thereof, ii) flight data selected from the group consisting of altitude, ambient air pressure, Mach number, engine throttle level, ambient air temperature, and combination thereof, and iii) vehicle-level data selected from the group consisting of positions of an engine inlet, displacements of the engine inlet, rotations of the engine inlet, wing or fuselage lift and drag control surfaces, and combinations thereof.

9. The method as recited in claim 8 , wherein the adjusting of the angle and the position result in a controlled change of temperature and pressure in the variable area exhaust nozzle to reduce aerodynamic drag of the engine exhaust and nozzle.

10. An aircraft control system comprising:
a turbine engine including at least one variable area turbine and a variable area exhaust nozzle; and
a controller configured to collect data that is indicative of an instant flight condition, enter the data into a decision algorithm that, based on the data, outputs first and second drag control parameters corresponding, respectively, to an angle of the at least one variable area turbine and a position of the variable area exhaust nozzle, and the decision algorithm also outputs a third drag control parameter corresponding to a fuel flow ratio between fuel flow to a combustor of the turbine engine and fuel flow to an augmentor of the turbine engine, adjust the angle and the position according to, respectively, the first and second drag control parameters to reduce aerodynamic drag of engine exhaust or nozzle of the turbine engine, and adjust total fuel flow and the fuel flow ratio in accordance with the third drag control parameter to reduce the aerodynamic drag of the engine exhaust and nozzle.

11. The aircraft control system as recited in claim 10 , wherein the data is selected from the group consisting of altitude, ambient air pressure, Mach number, throttle level, ambient air temperature, and combinations thereof.

12. The aircraft control system as recited in claim 10 , wherein the decision algorithm also outputs a fourth drag control parameter corresponding to a pressure ratio of the variable area exhaust nozzle, and the controller is also configured to adjust the pressure ratio in accordance with the fourth drag control parameter to reduce the aerodynamic drag.

13. The aircraft control system as recited in claim 10 , wherein the at least one variable area turbine includes a first variable area turbine in a low-pressure turbine section and a second variable area turbine in a high-pressure turbine section.

14. The aircraft control system as recited in claim 10 , wherein the data includes i) engine data selected from the group consisting of engine pressure ratio, shaft rotational speed, positions of variable vanes, and combinations thereof, ii) flight data selected from the group consisting of altitude, ambient air pressure, Mach number, engine throttle level, ambient air temperature, and combination thereof, and iii) vehicle-level data selected from the group consisting of positions of an engine inlet, displacements of the engine inlet, rotations of the engine inlet, wing or fuselage lift and drag control surfaces, and combinations thereof.

15. The aircraft control system as recited in claim 14 , wherein the decision algorithm also outputs a fourth drag control parameter corresponding to a pressure ratio of the variable area exhaust nozzle, and the controller is also configured to adjust the pressure ratio in accordance with the fourth drag control parameter to reduce the aerodynamic drag.

Assignees

• United Technologies Corp

Inventors

• Kupratis Daniel Bernard
• Suydam Adam Joseph
• Hugill Christopher G

Classifications

• F02C9/54

  by throttling the working fluid, by adjusting vanes · CPC title

• F02C9/28

  Regulating systems responsive to plant or ambient parameters, e.g. temperature, pressure, rotor speed (F02C9/30 - F02C9/38, F02C9/44 take precedence) · CPC title

• F02K1/17 Primary

  with control of fuel supply · CPC title

• F02K3/11

  by means of burners or combustion chambers · CPC title