Multiple annular swirler

• US 6,367,262 B1
• Filed: 09/29/2000
• Issued: 04/09/2002
• Est. Priority Date: 09/29/2000
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Chauvette, Claude Henry, Mongia, Hukam Chand, North, Gary Lee
• Primary Examiner(s): Freay, Charles G.
• Assistant Examiner(s): Gartenberg, Ehud
• Application Number:
  US09/675,665
• Time in Patent Office: 557 Days
• Field of Search: 607/46, 607/47, 607/48
• US Class Current: 60/748
• 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
• CPC Class Codes: F23R 3/343 Pilot flames, i.e. fuel nozzles or injectors using only a very small proportion of the total fuel to insure continuous combustion ignition in gas-turbine plants F02C7/264; pilot flame igniters F23Q9/00
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A mixer for use in a combustion chamber of a gas turbine engine. The mixer includes a first fuel injector adapted for dispensing droplets of fuel during ignition and low power settings of the engine and a pilot swirler positioned upstream from the first fuel injector. The pilot swirler has a plurality of vanes for swirling air to mix air and the droplets of fuel. The mixer also includes a second fuel injector adapted for dispensing droplets of fuel during high power settings of the engine and a main swirler adjacent the pilot swirler and upstream from the second fuel injector. The main swirler has a plurality of vanes for swirling air traveling through the main swirler to mix air and the droplets of fuel dispensed by the second fuel injector. The mixer also includes a barrier positioned between the pilot swirler and main swirler for separating the first fuel injector from the second fuel injector.

Claims

1. A mixer for use in a combustion chamber of a gas turbine engine, said mixer comprising:

a first fuel injector adapted for dispensing droplets of fuel during ignition and low power settings of the engine;

a pilot swirler positioned upstream from said first fuel injector having a plurality of vanes for swirling a first volume of air traveling through said pilot swirler to mix said first volume of air and the droplets of fuel dispensed by said first fuel injector to form a first fuel-air mixture selected for optimal burning during ignition and low power settings of the engine;

a second fuel injector adapted for dispensing droplets of fuel during high power settings of the engine;

a main swirler surrounding said pilot swirler and upstream from said second fuel injector having a plurality of vanes for swirling a second volume of air traveling through said main swirler to mix said second volume of air and the droplets of fuel dispensed by said second fuel injector to form a second fuel-air mixture selected for optimal burning during high power settings of the engine; and

an annular barrier positioned between said pilot swirler and said main swirler for separating said first fuel injector from said second fuel injector, said barrier defining a pilot mixing chamber downstream from said pilot swirler and partially defining an annular main mixing charter downstream from said main swirler.

2. A mixer as set forth in claim 1 wherein said pilot swirler is an axial swirler.

3. A mixer as set forth in claim 2 wherein said main swirler is a radial swirler.

4. A mixer as set forth in claim 1 wherein said pilot swirler is a radial swirler.

5. A mixer as set forth in claim 4 wherein said main swirler is a radial swirler.

6. A mixer as set forth in claim 1 wherein said second fuel injector includes a plurality of fuel injector ports positioned in the barrier.

7. A mixer as set forth in claim 1 wherein said first fuel injector includes a fuel injector port centrally positioned inside the barrier.

9. A mixer as set forth in claim 1 in combination with a combustion chamber comprising:

an annular outer liner defining an outer boundary of the combustion chamber;

an annular inner liner mounted inside the outer liner defining an inner boundary of the combustion chamber; and

an annular dome mounted upstream from the outer liner and the inner liner defining an upstream end of the combustion chamber, said mixer being positioned on the dome for delivering a mixture of fuel and air to the combustion chamber.

8. A mixer for use in a combustion chamber of a gas turbine engine, said mixer comprising:

a first fuel injector adapted for dispensing droplets of fuel during ignition and low power settings of the engine;

a pilot swirler positioned upstream from said first fuel injector having a plurality of vanes for swirling a first volume of air traveling through said pilot swirler to mix said first volume of air and the droplets of fuel dispensed by said first fuel injector to form a first fuel-air mixture selected for optimal burning during ignition and low power settings of the engine;

a second fuel injector adapted for dispensing droplets of fuel during high power settings of the engine;

a main swirler adjacent said pilot swirler and upstream from said second fuel injector having a plurality of vanes for swirling a second volume of air traveling through said main swirler to mix said second volume of air and the droplets of fuel dispensed by said second fuel injector to form a second fuel-air mixture selected for optimal burning during high power settings of the engine; and

a barrier positioned between said pilot swirler and said main swirler for separating said first fuel injector from said second fuel injector, wherein said first fuel injector includes a plurality of fuel injector ports arranged in a circle in the barrier.

10. A mixer as set forth in claim 8 wherein said pilot swirler is an axial swirler.

11. A mixer as set forth in claim 10 wherein said main swirler is a radial swirler.

12. A mixer as set forth in claim 8 wherein said pilot swirler is a radial swirler.

13. A mixer as set forth in claim 12 wherein said main swirler is a radial swirler.

14. A mixer as set forth in claim 8 wherein said main swirler surrounds said pilot swirler, and the barrier is an annular barrier positioned between said main swirler and said pilot swirler so that the barrier defines a pilot mixing chamber downstream from said pilot swirler and partially defines an annular main mixing chamber downstream from said main swirler.

15. A mixer as set forth in claim 14 wherein said second fuel injector includes a plurality of fuel injector ports positioned in the barrier.

16. A mixer as set forth in claim 8 wherein said first fuel injector includes a fuel injector port centrally positioned inside the barrier.

17. A mixer as set forth in claim 8 in combination with a combustion chamber comprising:

an annular outer liner defining an outer boundary of the combustion chamber;

an annular inner liner mounted inside the outer liner defining an inner boundary of the combustion chamber; and

an annular dome mounted upstream from the outer liner and the inner liner defining an upstream end of the combustion chamber, said mixer being positioned on the dome for delivering a mixture of fuel and air to the combustion chamber.