Mixing arrangement for mixing a fuel with a stream of oxygen containing gas

Patent metadata

Field	Value
Publication number	US-9822981-B2
Application number	US-201414493839-A
Country	US
Kind code	B2
Filing date	Sep 23, 2014
Priority date	Mar 26, 2012
Publication date	Nov 21, 2017
Grant date	Nov 21, 2017

Abstract

The invention relates to a mixing arrangement for mixing a fuel with a stream of oxygen containing gas flowing along an axis in an axial channel, especially in the second combustor of a gas turbine with sequential combustion. The mixing is improved and the mixing length reduced by said mixing arrangement comprising an injector with at least one injector ring, which is passed by said stream of gas inside and outside.

First claim

The invention claimed is:

1. A mixing arrangement for mixing a fuel with a stream of oxygen containing gas flowing along an axis in an axial channel in a second combustor of a gas turbine with sequential combustion, said mixing arrangement comprising:
an injector with at least one injector ring for injecting plural streams of different fluid types into the second combustor, wherein said at least one injector ring has a plurality of injection nozzles for injecting the plural streams of different fluid types distributed circumferentially in a plane perpendicular to said axis, wherein at least one of the plurality of injection nozzles injects a stream of a respective fluid in a direction of said stream of oxygen containing gas flowing along said axis, said stream of oxygen containing gas passes inside and outside the at least one injector ring along said axis, and said at least one injector ring has an aerodynamic profile in an axial direction.

2. The mixing arrangement according to claim 1 , wherein said at least one injector ring is circular with respect to said axis.

3. The mixing arrangement according to claim 1 , wherein said at least one injector ring has the aerodynamic profile of a symmetric airfoil with a symmetry plane being aligned with said axis.

4. The mixing arrangement according to claim 1 , wherein said at least one injector ring is designed to inject a plurality of streams of different fluids.

5. The mixing arrangement according to claim 4 , wherein said at least one injector ring is designed to inject a stream of liquid fuel, a stream of air, and a stream of fuel gas in a direction along said axis.

6. The mixing arrangement according to claim 4 , wherein at least three of the plurality of injection nozzles are arranged to each inject a different fluid into the second combustor.

7. The mixing arrangement according to claim 4 , wherein the plurality of injection nozzles are arranged in plural sets of at least three nozzles, and at least three nozzles within each set injects a different fluid into the second combustor.

8. The mixing arrangement according to claim 1 , an injection direction of each nozzle being aligned with said axis.

9. The mixing arrangement according to claim 8 , further comprising vortex generators provided on said at least one injector ring.

10. The mixing arrangement according to claim 9 , wherein said vortex generators are circumferentially distributed on said at least one injector ring such that each of said vortex generators corresponds to one of said plurality of inline injection nozzles.

11. The mixing arrangement according to claim 10 , wherein said vortex generators are arranged alternating on the inside and on the outside of said at least one injector ring.

12. The mixing arrangement according to claim 8 , further comprising lobes provided between neighbouring inline injection nozzles.

13. The mixing arrangement according to claim 12 , wherein said lobes are extending alternating to the inside and the outside of the at least one injector ring.

14. The mixing arrangement according to claim 1 , an injection direction of each nozzle being in crossflow orientation with respect to said stream of gas.

15. The mixing arrangement according to claim 1 , further comprising a plurality of injector rings is provided in a multi-ring configuration.

16. The mixing arrangement according to claim 15 , wherein the plurality of injector rings are of different sizes and are arranged in a same plane.

17. The mixing arrangement according to claim 15 , wherein the plurality of injector rings are of different size and are arranged at different axial locations.

18. The mixing arrangement according to claim 1 , wherein each type of fluid is supplied to a respective injection nozzle via a duct, the ducts for each type of fluid being nested and concentric about a supply axis of the injector.

Assignees

• Alstom Technology Ltd
• Ansaldo Energia Switzerland AG

Inventors

• Ciani Andrea
• Knoepfel Hanspeter

Classifications

• F23D99/004

  for use in particular heating operations · CPC title

• F23R3/346

  for staged combustion · CPC title

• F23R3/18 Primary

  Flame stabilising means, e.g. flame holders for after-burners of jet-propulsion plants · CPC title

• F23D91/02

  Mechanical Engineering · mapped topic

• F02K3/10

  by after-burners (F02K3/105 takes precedence) · CPC title