BLED DIFFUSER FED SECONDARY COMBUSTION SYSTEM FOR GAS TURBINES

• US 20110179803A1
• Filed: 01/27/2010
• Published: 07/28/2011
• Est. Priority Date: 01/27/2010
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (General Electric Company)
• Original Assignee: General Electric Company
• Inventors: HUGHES, MICHAEL JOHN, BERRY, JONATHAN DWIGHT
• Granted Patent: US 8,381,532 B2
• Time in Patent Office: Days
• US Class Current: 60/785
• CPC Class Codes: F01D 9/06 Fluid supply conduits to nozzles or the like
• CPC Class Codes: F02C 7/222 Fuel flow conduits, e.g. manifolds
• CPC Class Codes: F23R 3/346 for staged combustion

Abstract

The present subject matter provides a system for modifying static pressure recoveries and emissions formation within a gas turbine. The system includes a bled diffuser positioned downstream from a compressor section of the gas turbine and a bleed duct extending from the bled diffuser. The bleed duct may be configured to direct bleed air from the pressurized airflow exiting the compressor section to a secondary combustion system located downstream from the main combustion system in a combustor. The bleed air flowing into the secondary combustion system may be mixed with fuel to form an air/fuel mixture.

Claims

1. A system for modifying static pressure recovery and emissions formation within a gas turbine, the system comprising:

a bled diffuser positioned downstream from a compressor section of a gas turbine, said bled diffuser configured to diffuse a pressurized airflow flowing from said compressor section;

a secondary combustion system located downstream from a main combustion system in a combustor, said secondary combustion system comprising at least one fuel injector configured to receive and discharge fuel from a fuel source;

a bleed duct extending from said bled diffuser to said secondary combustion system, said bleed duct configured to direct bleed air from said pressurized airflow to said secondary combustion system; and

wherein said bleed air flowing into said secondary combustion system is mixed with the fuel discharged from said at least one fuel injector to form an air/fuel mixture.

2. The system of claim 1, wherein said bled diffuser is defined by a compressor discharge casing of said gas turbine.

3. The system of claim 1, wherein said bled diffuser comprises a vortex-controlled diffuser, said vortex-controlled diffuser comprising at least one vortex chamber configured to draw said bleed air from said pressurized airflow.

4. The system of claim 1, wherein said bleed duct is partially defined by a passageway formed in a compressor discharge casing of said gas turbine.

5. The system of claim 1, comprising a bracket configured to support a transition piece of said combustor, wherein said bleed duct is partially defined by at least one flowpath formed by said bracket.

6. The system of claim 5, wherein said at least one fuel injector is disposed within said at least one flowpath of said bracket.

7. The system of claim 5, comprising a first flow path and a second flow path formed within said bracket, wherein said secondary combustion system comprises a first fuel injector and a second fuel injector, said first fuel injector disposed within said first flow path, said second fuel injector disposed within said second flow path.

8. The system of claim 5, wherein said secondary combustion system comprises an air manifold disposed between said bracket and said transition piece, wherein said air manifold is configured to receive said bleed air from said bleed duct.

9. The system of claim 8, wherein said secondary combustion system comprises a plurality of fuel injectors, said plurality of fuel injectors being disposed within said air manifold.

10. The system of claim 1, wherein said air/fuel mixture flows through a cross-over tube and into a reaction zone of said combustor.

11. A gas turbine with modified static pressure recovery and emissions formation, the gas turbine comprising:

a compressor section configured to pressurize an airflow entering a gas turbine;

a combustor section comprising at least one combustor configured to receive said airflow flowing from said compressor section, said at least one combustor comprising a main combustion system for mixing and combusting an air/fuel mixture;

a turbine section disposed downstream of said combustor section, said turbine section configured to receive hot products of combustion from said combustor section;

at least one bled diffuser positioned downstream from said compressor section, said at least one bled diffuser configured to diffuse said airflow flowing from said compressor section;

a secondary combustion system located downstream from said main combustion system in said at least one combustor, said secondary combustion system comprising at least one fuel injector configured to receive and discharge fuel from a fuel source;

a bleed duct extending from said at least one bled diffuser to said secondary combustion system, said bleed duct configured to direct bleed air from said airflow to said secondary combustion system; and

wherein said bleed air flowing into said secondary combustion system is mixed with the fuel discharged from said at least one fuel injector to form an air/fuel mixture.

12. The gas turbine of claim 11, wherein said at least one bled diffuser is defined by a compressor discharge casing of said gas turbine.

13. The gas turbine of claim 11, wherein said at least one bled diffuser comprises a vortex-controlled diffuser, said vortex-controlled diffuser comprising at least one vortex chamber configured to draw said bleed air from said airflow.

14. The gas turbine of claim 11, wherein said bleed duct is partially defined by a passageway formed in a compressor discharge casing of said gas turbine.

15. The gas turbine of claim 11, comprising a bracket configured to support a transition piece of said at least one combustor, wherein said bleed duct is partially defined by at least one flowpath formed within said bracket.

16. The gas turbine of claim 15, wherein said at least one fuel injector is disposed within said at least one flowpath of said bracket.

17. The gas turbine of claim 15, comprising a first flow path and a second flow path formed within said bracket, wherein said secondary combustion system comprises a first fuel injector and a second fuel injector, said first fuel injector disposed within said first flow path, said second fuel injector disposed within said second flow path.

18. The gas turbine of claim 15, wherein said secondary combustion system comprises an air manifold disposed between said bracket and said transition piece, wherein said air manifold is configured to receive said bleed air from said bleed duct.

19. The gas turbine of claim 18, wherein said secondary combustion system comprises a plurality of fuel injections, said plurality of fuel injections being disposed within said air manifold.

20. The gas turbine of claim 11, wherein said air/fuel mixture flows through a cross-over tube and into a reaction zone of said at least one combustor.