MONOLITHIC FUEL INJECTOR AND RELATED MANUFACTURING METHOD

• US 20110057056A1
• Filed: 09/08/2009
• Published: 03/10/2011
• Est. Priority Date: 09/08/2009
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (General Electric Company)
• Original Assignee: General Electric Company
• Inventors: STEVENSON, Christian Xavier, ZIMINSKY, Willy Steve, JOHNSON, Thomas Edward, YORK, William David, LACY, Benjamin
• Granted Patent: US 8,181,891 B2
• Time in Patent Office: Days
• US Class Current: 239/398
• CPC Class Codes: B05B 1/14 with multiple outlet openings B05B1/02, B05B1/26 take precedence; with strainers in or outside the outlet opening
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: F23C 2900/9901 Combustion process using hydrogen, hydrogen peroxide water or brown gas as fuel
• CPC Class Codes: F23D 14/48 Nozzles
• CPC Class Codes: F23D 14/62 Mixing devices; Mixing tubes
• CPC Class Codes: F23D 2213/00 Burner manufacture specifications
• CPC Class Codes: F23R 2900/00002 Gas turbine combustors adapted for fuels having low heating value [LHV]
• CPC Class Codes: F23R 2900/00018 Manufacturing combustion chamber liners or subparts
• CPC Class Codes: F23R 3/286 having fuel-air premixing devices F23R3/30 takes precedence

Abstract

A monolithic fuel injection head for a fuel nozzle includes a substantially hollow vesicle body formed with an upstream end face, a downstream end face and a peripheral wall extending therebetween, an internal baffle plate extending radially outwardly from a downstream end of the bore, terminating short of the peripheral wall, thereby defining upstream and downstream fuel plenums in the vesicle body, in fluid communication by way of a radial gap between the baffle plate and the peripheral wall. A plurality of integral pre-mix tubes extend axially through the upstream and downstream fuel plenums in the vesicle body and through the baffle plate, with at least one fuel injection hole extending between each of the pre-mix tubes and the upstream fuel plenum, thereby enabling fuel in the upstream plenum to be injected into the plurality of pre-mix tubes. The fuel injection head is formed by direct metal laser sintering.

Claims

1. A monolithic fuel injection head for a fuel nozzle comprising:

a substantially hollow vesicle body formed with an upstream end face, a downstream end face and a peripheral wall extending therebetween;

a center opening in the upstream end face defined by a bore extending partially through said vesicle body, said bore adapted to receive a fuel feed tube;

an internal baffle plate extending radially outwardly from a downstream end of said bore, terminating short of said peripheral wall, thereby defining upstream and downstream fuel plenums in said vesicle body, in fluid communication by way of a radial gap between said baffle plate and said peripheral wall, such that, in use, fuel will flow from the fuel feed tube into said downstream fuel plenum, through said radial gap and into said upstream plenum; and

a plurality of integral pre-mix tubes extending axially through said upstream and downstream fuel plenums in said vesicle body and through said baffle plate, with inlets at said upstream end face and outlets at said downstream end face, with at least one fuel injection hole extending between each of said pre-mix tubes and said upstream fuel plenum, thereby enabling fuel in said upstream plenum to be injected into said plurality of pre-mix tubes.

2. The monolithic fuel injection head of claim 1 wherein said internal baffle plate is angled in a radially outward direction toward said downstream end face.

3. The monolithic fuel injection head of claim 1 wherein said plurality of pre-mix tubes are arranged in concentric annular rows, with pre-mix tubes in one row circumferentially offset from pre-mix tubes in an adjacent row.

4. The monolithic fuel injection head of claim 1 wherein each of said pre-mix tubes is flared outwardly at said inlets.

5. The monolithic fuel injection head of claim 1 wherein said annular bore is formed with a counter bore thereby defining an annular shoulder adapted to be engaged by a leading edge of the fuel feed tube.

6. The monolithic fuel injection head of claim 1 wherein said at least one fuel injection hole comprises four fuel injection holes substantially equally spaced about each of said pre-mix tubes.

7. The monolithic fuel injection head of claim 6 wherein each fuel injection hole is angled in a downstream direction and located between 0.500 and 0.850 inches from a respective one of said outlets.

8. The monolithic fuel injection head of claim 1 wherein each of said pre-mix tubes is formed with cooling fins in said downstream fuel plenum.

9. The monolithic fuel injection head of claim 1 wherein said internal baffle plate is formed with thinned score lines on an upstream side of said baffle plate, said thinned score lines arranged in a grid such that each pre-mix tube passing through said baffle plate is bounded by respective ones of said thinned score lines.

10. The monolithic fuel injection head of claim 6 wherein said fuel injection holes lie in a substantially common plane, and no fuel injection hole in one pre-mix tube lies directly opposite a fuel injection hole in an adjacent pre-mix tube.

11. A monolithic fuel injection head for a fuel nozzle comprising:

a substantially hollow vesicle body formed with an upstream end face, a downstream end face and a peripheral wall extending therebetween;

a center opening in the upstream end face defined by a bore extending partially through said vesicle body, said bore adapted to receive a fuel feed tube;

an internal baffle plate extending radially outwardly from a downstream end of said bore, terminating short of said peripheral wall, thereby defining upstream and downstream fuel plenums in said vesicle body in fluid communication by way of a radial gap between said baffle plate and said peripheral wall, such that, in use, fuel will flow from the fuel feed tube into said downstream fuel plenum, through said radial gap and into said upstream plenum; and

wherein said internal baffle plate is formed with thinned score lines on an upstream side of said baffle plate, said thinned score lines arranged in a grid pattern defining a plurality of spaces bounded by said thinned score lines;

a plurality of integral pre-mix tubes extending axially through said upstream fuel plenum, through respective ones of said spaces in said baffle plate and through said downstream fuel plenum in said vesicle body, with inlets at said upstream end face and outlets at said downstream end face, with at least one fuel injection hole extending between each of said pre-mix tubes and said upstream fuel plenum, thereby enabling fuel in said upstream plenum to be injected into said plurality of pre-mix tubes; and

wherein each of said pre-mix tubes is formed with cooling fins in said downstream fuel plenum.

12. The monolithic fuel injection head of claim 11 wherein each cooling fin is formed with a relatively small fillet radius where the cooling fin interfaces with its respective pre-mix tube on an upstream side of the cooling fin, and a relatively large fillet radius where the cooling fin interfaces with said respective pre-mix tube on a downstream side of the cooling fin.

13. The monolithic fuel injection head of claim 11 wherein said internal baffle plate is angled in a radially outward direction toward said downstream end face.

14. The monolithic fuel injection head of claim 11 wherein said at least one fuel injection hole comprises up to four fuel injection holes substantially equally spaced about each of said pre-mix tubes.

15. The monolithic fuel injection head of claim 11 wherein each fuel injection hole is angled in a downstream direction and located between 0.500 and 0.850 inches from a respective one of said outlets.

16. A method of producing a fuel injection head comprising:

(a) forming a substantially hollow vesicle body with an upstream end face, a downstream end face and a peripheral wall extending therebetween;

(b) forming a center opening in the upstream end face defined by a bore extending partially through said vesicle body, said bore adapted to receive a fuel feed tube for supplying fuel to said hollow vesicle body;

(c) forming a plurality of integral pre-mix tubes extending axially through said hollow vesicle body, with inlets at said upstream end face and outlets at said downstream end face; and

(d) forming at least one fuel injection hole extending between each of said pre-mix tubes and said hollow vesicle body; and

wherein steps (a) through (d) are carried out by direct laser metal sintering.

17. The method of claim 16 and further comprising forming cooling fins on each of said plurality of pre-mix tubes also by direct metal laser sintering.

18. The method of claim 16 and further comprising:

forming an internal baffle plate extending radially outwardly from a downstream end of said bore, terminating short of said peripheral wall, thereby defining upstream and downstream fuel plenums in said hollow vesicle body in fluid communication by a radial gap between said baffle plate and said peripheral wall, said at least one fuel injection hole extending between each of said pre-mix tubes and said upstream fuel plenum.

19. The method of claim 18 wherein said at least one fuel injection hole comprises up to four fuel injection holes substantially equally spaced about each of said premix tubes, with each fuel injection hole angled in a downstream direction.

20. The method of claim 17 including forming each cooling fin with a relatively small fillet radius where the cooling fin interfaces with its respective pre-mix tube on an upstream side of the cooling fin, and a relatively large fillet radius where the cooling fin interfaces with said respective pre-mix tube on a downstream side of the cooling fin.