Low NOx combustor for gas turbine engine

• US 6,240,731 B1
• Filed: 12/31/1997
• Issued: 06/05/2001
• Est. Priority Date: 12/31/1997
• Status: Expired due to Term

• Current Assignee: United Technologies Corporation (Rtx Corporation)
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: Segalman, Irving, Smith, Reid D. C., Siskind, Kenneth S., Hoke, James B.
• Primary Examiner(s): Kim, Ted
• Application Number:
  US09/001,889
• Time in Patent Office: 1,252 Days
• Field of Search: 607/48, 607/32, 607/52, 239/400, 239/403, 239/405
• US Class Current: 60/732
• CPC Class Codes: F23C 2201/102 in horizontal direction
• CPC Class Codes: F23C 6/045 with staged combustion in a single enclosure
• CPC Class Codes: F23C 7/004 using vanes
• CPC Class Codes: F23C 7/02 Disposition of air supply not passing through burner to obtain a cyclonic tapering flame when burning pulverulent fuel F23C5/32
• CPC Class Codes: F23D 11/107 at least one of both being subjected to a swirling motion
• CPC Class Codes: F23D 2206/10 Turbines
• CPC Class Codes: F23D 2900/11101 Pulverising gas flow impinging on fuel from pre-filming surface, e.g. lip atomizers
• CPC Class Codes: F23R 3/06 Arrangement of apertures along the flame tube
• CPC Class Codes: Y02E 20/34 Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

Abstract

A method of combusting fuel in the combustor of a gas turbine engine is disclosed which includes injecting fuel and a first predetermined amount of airflow into the combustion chamber to form a fuel-rich, highly mixed, uniform distribution fuel-air spray pattern flowing downstream in the combustion chamber and introducing a second predetermined amount of airflow into the fuel air spray pattern from combustor air inlets positioned at a first predetermined distance downstream from the combustor dome with the first predetermined distance being greater than 0.75 times the dome height and said second predetermined amount of airflow being sufficient to cause rapid mixing and quenching of the rich fuel-air mixture to a lean fuel-air mixture. A combustor for a gas turbine engine is also disclosed which includes sidewalls and a dome wall to form a combustion chamber, a fuel injector/air swirler assembly for injecting a fuel air spray, a first and second array of air inlets for introducing airflow into the combustion chamber sufficient to cause rapid combustion and rapidly resulting lean-fuel air mixture, the first array being positioned a predetermined distance downstream from the dome wall with the predetermined distance being greater than 0.75 times the dome height and the second array of air inlets being positioned downstream from the first array.

Claims

1. A combustor for a gas turbine engine comprising:

first and second sidewall sections connected to a dome end wall to form an elongated combustion chamber having an upstream end and a downstream end;

said dome wall being disposed at the upstream end of the combustion chamber and having a predetermined dome height;

a fuel injector/air swirler assembly mounted in the dome wall for injecting a fuel air spray into the combustion chamber, said fuel injector/swirler assembly being configured to produce a fuel-rich highly mixed fuel-air spray pattern with uniform distribution;

side sidewalls containing a first and second array of air inlets configured for introducing airflow into the combustion chamber sufficient to cause rapid combustion and a rapidly resulting lean-fuel air mixture;

said first array of air inlets being disposed to direct air inflow into the fuel-air spray pattern in the combustion chamber and positioned a predetermined distance downstream from said dome wall, said predetermined distance being greater than 0.75 times said dome height; and

said second array of air inlets being disposed to direct air inflow into the fuel-air spray pattern in the combustion chamber and positioned downstream from said first array;

said fuel injector/air swirler assembly comprises;

a fuel delivery passage having a discharge outlet for discharging fuel;

a first airflow swirler having a first outlet disposed to provide swirling air to discharging fuel, said first swirler being an axial inflow swirler configured to swirl air in a first angular direction;

a second airflow swirler having a second outlet disposed to provide swirling air to discharging fuel, said second swirler being a radial inflow swirler configured to swirl air in said first angular direction;

said first and second outlets being positioned to provide swirling air to fuel at said discharge outlet to produce a downstream-flowing fuel air mixture; and

a third airflow swirler having a third outlet disposed to provide swirling air to said fuel air mixture, said third swirler being a radial inflow swirler configured to swirl air in said first angular direction.

2. The device of claim 1 comprising

a fourth air flow swirler having a fourth outlet disposed to provide swirling air to said fuel air mixture, said fourth swirler being a radial inflow swirler with said fourth outlet disposed about said third outlet of said third swirler and configured to swirl air in said first angular direction.

3. The device of claim 1 comprising

an array of air passages about said third outlet of said third swirler, said array of air passages configured to discharge air approximately parallel to said third airflow swirler.

4. A combustor for a gas turbine engine comprising:

first and second sidewall sections connected to a dome end wall to form an elongated combustion chamber having an upstream end and a downstream end;

said dome wall being disposed at the upstream end of the combustion chamber and having a predetermined dome height;

a fuel injector/air swirler assembly mounted in the dome wall to injecting a fuel air spray into the combustion chamber, said fuel injector/swirler assembly being configured to produce a fuel-rich highly mixed fuel-air spray pattern with uniform distribution;

side sidewalls containing a first and second array of air inlets configured for introducing airflow into the combustion chamber sufficient to cause rapid combustion and a rapidly resulting lean-fuel air mixture;

said first array of air inlets being disposed to direct air inflow into the fuel-air spray pattern in the combustion chamber and positioned a predetermined distance downstream from said dome wall, said predetermined distance being greater than 0.75 times said dome height; and

said second array of air inlets being disposed to direct air inflow into the fuel-air spray pattern in the combustion chamber and positioned downstream from said first array;

said fuel injector/air swirler assembly comprises;

a fuel delivery passage having a discharge outlet for discharging fuel;

a first airflow swirler having a first outlet disposed to provide swirling air to discharging fuel, said first swirler being an axial inflow swirler configured to swirl air in a first angular direction;

a second airflow swirler having a second outlet disposed to provide swirling air to discharging fuel, said second swirler being a radial inflow swirler configured to swirl air in said first angular direction;

said first and second outlets being positioned to provide swirling air to fuel at said discharge outlet to produce a downstream-flowing fuel air mixture;

a third airflow swirler having a third outlet disposed to provide swirling air to said fuel air mixture, said swirling air to said fuel air mixture, said third swirler being a radial inflow swirler configured to swirl air in a second angular direction opposite to said first angular direction; and

a fourth airflow swirler having a fourth outlet disposed to provide swirling air to said fuel air mixture, said fourth swirler being a radial inflow swirler with said fourth outlet disposed about said third outlet of said third swirler and configured to swirl air in said second angular direction.

5. A combustor for a gas turbine engine comprising:

first and second sidewall sections connected to a dome end wall to form an elongated combustion chamber having an upstream end and a downstream end;

said dome wall being disposed at the upstream end of the combustion chamber and having a predetermined dome height;

a fuel injector/air swirler assembly mounted in the dome wall for injecting a fuel air spray into the combustion chamber, said fuel injector/swirler assembly being configured to produce a fuel-rich highly mixed fuel-air spray pattern with uniform distribution;

said sidewalls containing a first and second array of air inlets configured for introducing airflow into the combustion chamber sufficient to cause rapid combustion and a rapidly resulting lean-fuel air mixture;

said first array of air inlets being disposed to direct air inflow into the fuel-air spray pattern in the combustion chamber and positioned a predetermined distance downstream from said dome wall, said predetermined distance being greater than 0.75 times said dome height; and

said second array of inlets being disposed to direct air inflow into the fuel-air spray pattern in the combustion chamber and positioned downstream from said first array;

said fuel injector/air swirler assembly comprises;

a fuel delivery passage having a discharge outlet for discharging fuel;

a first airflow swirler having a first outlet disposed to provide swirling air to discharging fuel, said first swirler being an axial inflow swirler configured to swirl air in a first angular direction;

a second airflow swirler having a second outlet disposed to provide swirling air to discharging fuel, said second swirler being a radial inflow swirler configured to swirl air in said first angular direction;

said first and second outlets being positioned to provide swirling air to fuel at said discharge outlet to produce a downstream-flowing fuel air mixture;

a third airflow swirler having a third outlet disposed to provide swirling air to said fuel mixture, said third swirler being a radial inflow swirler configured to swirl air in a second angular direction opposite to said first angular direction; and

a fourth airflow swirler having a fourth outlet disposed to provide swirling air to said fuel air mixture, said fourth swirler being a radial inflow swirler with said fourth outlet disposed about said third outlet of said third swirler and configured to swirl air in said first angular direction.

6. A combustor for a gas turbine engine comprising:

first and second sidewall sections connected to a dome end wall to form an elongated combustion chamber having an upstream end and a downstream end;

said dome wall being disposed at the upstream end of the combustion chamber and having a predetermined dome height;

a fuel injector/air swirler assembly mounted in the dome wall for injecting a fuel air spray into the combustion chamber, said fuel injector/swirler assembly being configured to produce a fuel-rich highly mixed fuel-air spray pattern with uniform distribution;

said sidewalls containing a first and second array of air inlets configured for introducing airflow into the combustion chamber sufficient to cause rapid combustion and a rapidly resulting lean-fuel air mixture;

said first array of air inlets being disposed to direct air inflow into the fuel-air spray pattern in the combustion chamber and positioned a predetermined distance downstream from said dome wall, said predetermined distance being greater than 0.75 times said dome height; and

said second array of air inlets being disposed to direct air inflow into the fuel-air spray pattern in the combustion chamber and positioned downstream from said first array;

said fuel injector/air swirler assembly comprises;

a fuel delivery passage having a discharge outlet for discharging fuel;

a first airflow swirler having a first outlet disposed to provide swirling air to discharging fuel, said first swirler being an axial inflow swirler configured to swirl air in a first angular direction;

a second airflow swirler having a second outlet disposed to provide swirling air to discharging fuel, said second swirler being a radial inflow swirler configured to swirl air in said first angular direction;

said first and second outlets being positioned to provide swirling air to fuel at said discharge outlet to produce a downstream-flowing fuel air mixture;

a third airflow swirler having a third outlet disposed to provide swirling air to said fuel air mixture, said third swirler being a radial inflow swirler configured to swirl air in a second angular direction opposite to said first angular direction; and

an array of air passages about said third outlet of said third swirler, said array of air passages configured to discharge air approximately parallel to said third airflow swirler.