Fuel system for tone control and operability

Patent metadata

Field	Value
Publication number	US-9605598-B2
Application number	US-201514884487-A
Country	US
Kind code	B2
Filing date	Oct 15, 2015
Priority date	Oct 17, 2014
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

Aspects of the disclosure are directed to controlling a distribution of fuel to a plurality of nozzles associated with at least one aircraft engine by: determining a state of operation associated with the at least one aircraft engine, causing a valve coupled to a fuel supply and each of the nozzles to open when it is determined that the state of operation indicates a high power state relative to at least one threshold, and causing the valve to close when it is determined that the state of operation indicates a low power state relative to the at least one threshold.

First claim

What is claimed is:

1. A method for controlling a distribution of fuel to a plurality of nozzles associated with at least one aircraft engine, the method comprising:
determining, by a processor, a state of operation associated with the at least one aircraft engine;
causing, by the processor, a valve coupled to a fuel supply and each of the nozzles to open when it is determined that the state of operation indicates a high power state relative to at least one threshold;
causing, by the processor, the valve to close when it is determined that the state of operation indicates a low power state relative to the at least one threshold;
establishing, by the processor, a first primary flow number for a first group of the nozzles; and
establishing, by the processor, a second primary flow number that is different from the first primary flow number for a second group of the nozzles to account for head-effects.

2. The method of claim 1 , wherein the second primary flow number is less than the first primary flow number, and wherein the first group of nozzles is located at a higher altitude than the second group of nozzles.

3. The method of claim 1 , wherein the fuel supply is coupled to a first group of the nozzles via a primary line, and wherein the valve is coupled to a second group of the nozzles via a secondary line, the method comprising:
establishing a differential pressure of approximately 20 pounds per square inch between the primary line and the secondary line when the valve is open; and
establishing a differential pressure of approximately 120 pounds per square inch between the primary line and the secondary line when the valve is closed.

4. A system for controlling a distribution of fuel on an aircraft, the system comprising:
a plurality of nozzles associated with at least one aircraft engine; and
a valve coupled to a fuel supply and each of the nozzles,
wherein the valve is configured to be opened when a state of operation associated with the at least one aircraft engine indicates a high power state relative to at least one threshold, and
wherein the valve is configured to be closed when the state of operation associated with the at least one aircraft engine indicates a low power state relative to the at least one threshold, and
wherein a first group of the nozzles has an associated first primary flow number, and wherein a second group of the nozzles has an associated second primary flow number that is different from the first primary flow number to account for head-effects.

5. The system of claim 4 , further comprising:
a primary line configured to couple the fuel supply to a subset of the nozzles; and
a secondary line configured to couple the valve and each of the nozzles.

6. The system of claim 5 , wherein the valve is configured to establish a differential pressure of approximately 20 pounds per square inch between the primary line and the secondary line when the valve is open, and wherein the valve is configured to establish a differential pressure of approximately 120 pounds per square inch between the primary line and the secondary line when the valve is closed.

7. The system of claim 5 , wherein the subset of nozzles corresponds to between one-sixth and one-third of the plurality of nozzles, inclusive.

8. The system of claim 4 , wherein the nozzles are arranged in a ring.

9. The system of claim 4 , wherein the second primary flow number is less than the first primary flow number, and wherein the first group of nozzles is located at a higher altitude than the second group of nozzles.

10. The system of claim 9 , wherein the first primary flow number and the second primary flow number are each expressed as an amount of fuel flow divided by the square root of a pressure drop, and wherein the first primary flow number is equal to approximately 2.0, and wherein the second primary flow number is equal to approximately 1.5.

11. The system of claim 4 , wherein the first primary flow number is based on a first size of holes machined into the first group of nozzles, and wherein the second primary flow number is based on a second size of holes machined into the second group of nozzles, and wherein the second size is different from the first size.

12. A system for controlling a distribution of fuel on an aircraft, the system comprising:
a first manifold inlet coupled to a subset of a plurality of nozzles;
a second manifold inlet coupled to each of the nozzles;
a primary line coupled to the first manifold inlet and a fuel supply;
a valve coupled to the fuel supply; and
a secondary line coupled to the valve and the second manifold inlet,
wherein a first group of the subset of the nozzles has an associated first primary flow number, and wherein a second group of the subset of the nozzles has an associated second primary flow number that is different from the first primary flow number to account for head-effects.

13. The system of claim 12 , wherein the valve is configured to be opened when a state of operation associated with at least one engine of the aircraft indicates a high power state relative to at least one threshold, and wherein the valve is configured to be closed when the state of operation associated with the at least one engine indicates a low power state relative to the at least one threshold, and wherein the at least one threshold is based on a maximum thrust associated with the at least one engine.

14. The system of claim 12 , further comprising:
at least one processor; and
memory having instructions stored thereon that, when executed by the at least one processor, cause the system to:
determine a state of operation associated with at least one engine of the aircraft;
cause the valve to open when it is determined that the state of operation indicates a high power state relative to at least one threshold; and
cause the valve to close when it is determined that the state of operation indicates a low power state relative to the at least one threshold.

15. The system of claim 12 , wherein the valve is configured to establish a differential pressure of approximately 20 pounds per square inch between the primary line and the secondary line when the valve is open, and wherein the valve is configured to establish a differential pressure of approximately 120 pounds per square inch between the primary line and the secondary line when the valve is closed.

16. The system of claim 12 , wherein the second primary flow number is less than the first primary flow number, and wherein the first group of nozzles is located at a higher altitude than the second group of nozzles.

17. The system of claim 12 , wherein the first primary flow number and the second primary flow number are each expressed as an amount of fuel flow divided by the square root of a pressure drop, and wherein the first primary flow number is equal to approximately 2.0, and wherein the second primary flow number is equal to approximately 1.5.

Assignees

• United Technologies Corp

Inventors

• Hoke James B
• Van Anthony

Classifications

• F02C9/34

  Joint control of separate flows to main and auxiliary burners · CPC title

• F02C7/228 Primary

  Dividing fuel between various burners · CPC title

• F02C9/263 Primary

  by means of fuel metering valves · CPC title

• F05D2270/14

  to control thermoacoustic behaviour in the combustion chambers · CPC title

• F02C7/232

  Fuel valves {(control of fuel supply by means of fuel metering valves F02C9/263)}; Draining valves or systems (valves in general F16K) · CPC title