Method and apparatus for enabling engine turn down

• US 20070151257A1
• Filed: 01/05/2006
• Published: 07/05/2007
• Est. Priority Date: 01/05/2006
• Status: Abandoned Application

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: West, James, Johnson, David, Maier, Mark, Martin, Devin
• Application Number:
  US11/325,861
• Publication Number:
  US 20070151257A1
• Time in Patent Office: Days
• US Class Current: 60/782
• CPC Class Codes: F01D 25/12 Cooling
• CPC Class Codes: F01D 5/189 the insert having a tubular cross-section, e.g. airfoil shape
• CPC Class Codes: F01D 9/06 Fluid supply conduits to nozzles or the like
• CPC Class Codes: F02C 3/13 having variable working fluid interconnections between turbines or compressors or stages of different rotors controlling flow ratio between different flows of multi-flow jet-propulsion plant, e.g. ducted fan F02K3/075
• CPC Class Codes: Y02E 20/16 Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT]

Abstract

Disclosed herein is a method for enabling turn down of a turbine engine, comprising: extracting compressor discharge air from a working fluid path before it enters a combustion zone of the turbine engine; and reintroducing the extracted air to the working fluid path downstream of a combustor exit. Further disclosed herein is an apparatus related to a gas turbine, comprising: a compressor section, one or more combustors downstream from the compressor section, a turbine section downstream from the compressor section; and at least one conduit for extracting compressor discharge air from a working fluid path prior to a combustion zone and reintroducing the extracted air to the working fluid path downstream of a combustor exit in response to the turbine being in a turned down condition.

Claims

1. A method for enabling turn down of a turbine engine, comprising:

extracting compressor discharge air from a working fluid path before it enters a combustion zone of the turbine engine; and

reintroducing the extracted air to the working fluid path downstream of a combustor exit.

2. The method of claim 1, further comprising:

pumping the extracted air with a pump.

3. The method of claim 2, further comprising:

driving the pump with the turbine engine.

4. The method of claim 2 further comprising:

varying the pump speed to vary flow rates of extracted air to maintain air fuel ratio.

5. The method of claim 2 wherein the pump is integral to the turbine engine.

6. The method of claim 2, further comprising:

varying extracted flow rates with a valve to maintain air fuel ratio.

7. The method of claim 1, further comprising:

varying extracted flow rates with a valve to maintain air fuel ratio.

8. The method of claim 1, further comprising:

acquiring the extracted air from a combustor head.

9. The method of claim 1, further comprising:

reintroducing the extracted air into a nozzle.

10. The method of claim 9, further comprising:

reintroducing the extracted air through holes in an airfoil and holes in a platform of the nozzle; and

sizing the holes in the airfoil and the holes in the platform to proportion air flow therethrough to improve uniformity of cooling.

11. The method of claim 9, wherein the nozzle is a first stage nozzle.

12. The method of claim 1, further comprising:

maintaining adequate combustor temperatures to meet desired emissions levels.

13. A gas turbine, comprising:

a compressor section;

one or more combustors downstream from the compressor section;

a turbine section downstream from the compressor section; and

at least one conduit for extracting compressor discharge air from a working fluid path prior to a combustion zone and reintroducing the extracted air to the working fluid path downstream of a combustor exit in response to the turbine being in a turned down condition.

14. The gas turbine of claim 13, wherein:

a pump pumps the extracted air.

15. The gas turbine of claim 14, wherein:

the pump is driven by the gas turbine.

16. The gas turbine of claim 14, wherein:

the pump speed is variable to vary the flow rates of the extracted air.

17. The gas turbine of claim 14, wherein:

the pump is integral to the turbine.

18. The gas turbine of claim 13, wherein:

the conduits are fluidically connected to at least one combustor head.

19. The gas turbine of claim 13, wherein:

the extracted air is reintroduced through a nozzle.

20. The gas turbine of claim 19, wherein:

the extracted air is reintroduced through holes in at least one airfoil and holes in at least one platform of the nozzle.