FUEL/AIR PREMIXING SYSTEM FOR TURBINE ENGINE

• US 20130283805A1
• Filed: 04/30/2012
• Published: 10/31/2013
• Est. Priority Date: 04/30/2012
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (General Electric Company)
• Original Assignee: General Electric Company
• Inventors: Zuo, Baifang
• Granted Patent: US 8,925,323 B2
• Time in Patent Office: Days
• US Class Current: 60/748
• CPC Class Codes: F23C 2900/07001 Air swirling vanes incorporating fuel injectors
• CPC Class Codes: F23R 3/14 by using swirl vanes
• CPC Class Codes: F23R 3/286 having fuel-air premixing devices F23R3/30 takes precedence

Abstract

A system includes a fuel nozzle. The fuel nozzle includes a center body configured to receive a first portion of air and to deliver the air to a combustion region. The fuel nozzle also includes a swirler configured to receive a second portion of air and to deliver the air to the combustion region. The swirler includes an outer shroud wall, an inner hub wall, and a swirl vane. The swirl vane includes a radial swirl profile at a downstream edge of the swirl vane. The radial swirl profile includes a region extending from the outer shroud wall to a first transition point and a second region extending from the transition point to the inner hub wall. At least one of the first and second regions is substantially straight and at least one of the first and second regions is arcuate.

Claims

1. A system, comprising:

a fuel nozzle, comprising;

a center body configured to receive a first portion of air and to deliver the air to a combustion region; and

a swirler configured to receive a second portion of air and to deliver the air to the combustion region, wherein the swirler comprises;

an outer shroud wall;

an inner hub wall; and

a swirl vane with a radial swirl profile at a downstream edge of the swirl vane, wherein the radial swirl profile comprises a first region extending from the outer shroud wall to a transition point and a second region extending from the transition point to the inner hub wall, and at least one of the first and second regions is substantially straight and at least one of the first and second regions is arcuate.

2. The system of claim 1, wherein the center body includes a diffusion swirler configured to induce a swirl to a subportion of the first portion of air.

3. The system of claim 1, wherein the radial swirl profile forms a first swirl angle at the outer shroud wall and the radial swirl profile forms a second swirl angle at the inner hub wall, and the first swirl angle is greater than the second swirl angle.

4. The system of claim 3, wherein the first swirl angle is between approximately 40 degrees and approximately 60 degrees.

5. The system of claim 3, wherein the second swirl angle is below approximately 20 degrees.

6. The system of claim 1, wherein the ratio of the first portion of air relative to the second portion of air is approximately 0.05 to approximately 0.25.

7. The system of claim 1, wherein the transition point is disposed proximate to a center of the radial swirl profile.

8. The system of claim 1, comprising a gas turbine comprising the combustor and the fuel nozzle.

9. A method, comprising:

directing a first portion of air through a center body of a fuel nozzle, wherein the first portion of air exits the center body with a first swirl angle near a hub wall of the fuel nozzle; and

directing a second portion of air through a swirler of the fuel nozzle, wherein the second portion of air exits the swirler with a second swirl angle near a shroud wall of the fuel nozzle, the second portion of air exits the swirler with a third swirl angle near the hub wall of the fuel nozzle, and the second swirl angle is greater than the third swirl angle.

10. The method of claim 9, wherein the ratio of the first portion of air relative to the second portion of air is approximately 0.05 to approximately 0.25.

11. The method of claim 9, comprising inducing the first swirl angle of the first portion of air exiting the center body at an angle between approximately 30 degrees and approximately 50 degrees.

12. The method of claim 9, comprising inducing the second swirl angle of the second portion of air exiting the swirler near the shroud wall at an angle between approximately 40 degrees and approximately 60 degrees.

13. The method of claim 9, comprising inducing the third swirl angle of the second portion of air exiting the swirler near the hub wall at an angle below approximately 20 degrees.

14. The method of claim 9, comprising directing the second portion of air through the swirler, wherein the swirler has a swirl vane with a radial swirl profile at a downstream edge of the swirl vane, and the radial swirl profile comprises a first region extending from the outer shroud wall to a transition point and a second region extending from the transition point to the inner hub wall.

15. The method of claim 14, wherein the first region of the radial swirl profile is substantially constant or decreasing toward the transition point, and the second region of the radial swirl profile is substantially decreasing toward the hub walls.

16. A system, comprising:

a fuel nozzle swirler, comprising;

an outer shroud wall;

an inner hub wall; and

a swirl vane with a radial swirl profile at a downstream edge of the swirl vane, wherein the radial swirl profile comprises a first region extending from the outer shroud wall to a transition point and a second region extending from the transition point to the inner hub wall, and the first region is substantially constant and the second region is substantially decreasing toward the hub wall.

17. The system of claim 16, wherein the radial swirl profile forms a first swirl angle of the first region at the outer shroud wall, the radial swirl profile forms a second swirl angle of the second region at the inner hub wall, and the first swirl angle is greater than the second swirl angle.

18. The system of claim 17, wherein the first swirl angle is between approximately 40 degrees and approximately 60 degrees.

19. The system of claim 17, wherein the second swirl angle is below approximately 20 degrees.

20. The system of claim 16, wherein the transition point is disposed proximate to a center of the radial swirl profile.