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A trapped vortex combustor for gas turbine engines. An annular combustor housing is provided having a plurality of inlet centerbodies disposed along a helical axis. The inlet centerbodies include a leading edge structure, opposing sidewalls, a pressurizable cavity, and a rear wall. Inlet centerbodie

A trapped vortex combustor for gas turbine engines. An annular combustor housing is provided having a plurality of inlet centerbodies disposed along a helical axis. The inlet centerbodies include a leading edge structure, opposing sidewalls, a pressurizable cavity, and a rear wall. Inlet centerbodies cooperate with adjacent structure and an aft bluff body to define a trapped vortex cavity combustion chamber for mixing an inlet fluid and burning fuel to form hot combustion gases. Mixing is enhanced by utilizing struts adjacent to the rear wall to create eddies in the fluid flow, and by injecting fuel and/or air in opposition to swirl created by the bulk fluid flow. Hot combustion gases are utilized in a turbine for extraction of kinetic energy, or in heat exchange equipment for recovery of thermal energy. High combustion efficiencies and less than 10 ppm emissions of oxides of nitrogen and of carbon monoxide are achieved.

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The invention claimed is: 1. A trapped vortex combustor, said trapped vortex combustor comprising: (a) one or more trapped vortex cavities; (b) an air supply system to supply inlet air; (c) a fuel supply system for the supply of gaseous fuel, said fuel supply system comprising (i) a premix stage wh

The invention claimed is: 1. A trapped vortex combustor, said trapped vortex combustor comprising: (a) one or more trapped vortex cavities; (b) an air supply system to supply inlet air; (c) a fuel supply system for the supply of gaseous fuel, said fuel supply system comprising (i) a premix stage wherein fuel from said fuel supply system is mixed with said inlet air to provide a lean pre-mixture upstream of a first one of said one or more trapped vortex cavities; (ii) at least one fuel stage comprising one or more injectors in fluid communication with said fuel supply system, at least one of said one or more injectors configured to inject fuel into a first one of said one or more trapped vortex cavities; (d) said first one of said one or more trapped vortex cavities configured to provide a bulk fluid swirl in a predetermined direction; (e) said at least one of said one or more injectors that is configured to inject fuel into said first one of said one or more trapped vortex cavities oriented to provide a jet from said at least one injector to provide momentum of fuel and burning gases in opposition to said bulk fluid swirl predetermined direction. 2. A combustor as set forth in claim 1, comprising two or more injectors in fluid communication with said fuel supply system, each of said two or more injectors directed to provide a jet of fuel to provide momentum in opposition to said bulk fluid swirl predetermined direction. 3. A combustor as set forth in claim 1, wherein said combustor comprises a forebody having a rear wall, and a first aft body having a forward wall, and wherein a first one of said one or more trapped vortex cavities is located between said forebody rear wall and said aft body forward wall. 4. A combustor as set forth in claim 3, wherein said combustor comprises a second aft body having a forward wall, and wherein said first aft body further comprises a rear wall, and wherein a second one of said one or more trapped vortex cavities is located between said rear wall of said first aft body and said forward wall of said second aft body. 5. A combustor as set forth in claim 4, wherein said combustor includes at least a first fuel stage and a second fuel stage, and wherein said second fuel stage provides at least one fuel injector to supply fuel to said second one of said one or more trapped vortex cavities. 6. A combustor as set forth in claim 5, wherein said blockage ratio is approximately 63 percent. 7. A combustor as set forth in claim 3, wherein said combustor comprises one or more duct passageways adjacent to said forebody, and wherein said forebody rear wall defines a dump plane having a cross-sectional area, and wherein said cross-sectional area of said dump plane is the sum of (i) the cross-sectional area of said forebody rear wall and (ii) the cross-sectional area of one or more duct passageways adjacent to said forebody rear wall, and wherein a blockage ratio determined by dividing the cross-sectional area of said forebody rear wall by the total dump plane cross-sectional area is in excess of 60 percent. 8. A combustor as set forth in claim 3, wherein said rear wall of said forebody is cooled by effusion cooling. 9. A combustor as set forth in claim 3, wherein said rear wall of said forebody is cooled by impingement cooling. 10. A combustor as set forth in claim 3, wherein said first aft body is cooled by effusion cooling. 11. A combustor as set forth in claim 3, further comprising one or more side struts extending outward from said forebody. 12. A combustor as set forth in claim 11, wherein said side struts extend outward from a location adjacent said forebody rear wall. 13. A combustor as set forth in claim 11 or in claim 12, wherein said side struts comprise cylindrical dowels. 14. A combustor as set forth in claim 11 or in claim 12, wherein said side struts comprise a partial airfoil shape having a downstream end portion. 15. A combustor as set forth in claim 3, wherein said forebody further comprises an outer sidewall sufficiently sealingly affixed to said rear wall of said forebody to form within said forebody a pressurizable cooling air plenum, said cooling air plenum in fluid communication with said rear wall of said forebody, so as to supply impingement cooling to said rear wall of said forebody. 16. A combustor as set forth in claim 15 wherein said rear wall comprises a plurality of perforations in fluid communication between said pressurizable cooling air plenum and said first one of said one or more trapped vortex cavities, said plurality of perforations configured to provide effusion cooling to said rear wall of said forebody. 17. A combustor as set forth in claim 16, wherein said perforations are provided at a selected pitch angle and yaw angle with respect to said rear wall. 18. A combustor as set forth in claim 17, wherein said pitch angle of said perforations is about 30 degrees upward. 19. A combustor as set forth in claim 18, wherein said yaw angle is about 30 degrees. 20. A combustor as set forth in claim 17, wherein said perforations are provided with uniform pitch and yaw angles, so as to create a cooling air film that sweeps across said rear wall of said forebody. 21. A combustor as set forth in claim 3, further comprising a cooling air supply system, and wherein said first aft bluff body comprises a plurality of perforations in fluid communication with said cooling air supply system, said plurality of perforations configured to provide effusion cooling to said forward wall of said first aft bluff body. 22. A combustor as set forth in claim 21, wherein said perforations are provided at a selected pitch angle and yaw angle with respect to said forward wall of said first aft bluff body. 23. A combustor as set forth in claim 22, wherein said pitch angle of said perforations is about 30 degrees upward. 24. A combustor as set forth in claim 23, wherein said yaw angle is about 30 degrees. 25. A combustor as set forth in claim 22, wherein said perforations are provided with uniform pitch and yaw angles, so as to create a cooling air film that sweeps across said forward wall of said first aft bluff body. 26. The apparatus as set forth in claim 1, wherein emissions of oxides of nitrogen (NOx) are less than 20 parts per million, corrected to 15% oxygen. 27. The apparatus as set forth in claim 1, wherein emissions of oxides of nitrogen (NOx) are less than 10 parts per million, corrected to 15% oxygen. 28. The apparatus as set forth in claim 1, wherein emissions of carbon monoxide is less than 20 parts per million, corrected to 15% oxygen. 29. The apparatus as set forth in claim 1, wherein emissions of carbon monoxide is less than 10 parts per million, corrected to 15% oxygen. 30. The apparatus as set forth in claim 1, wherein (a) emissions of oxides of nitrogen (NOx) are less than 10 parts per million, corrected to 15% oxygen, and (b) emissions of carbon monoxide are less than 10 parts per million, corrected to 15% oxygen. 31. The apparatus as set forth in claim 30, wherein combustion efficiency exceeds 99.5 percent. 32. The apparatus as set forth in claim 30, wherein combustion efficiency is equal to or greater than 99.9 percent. 33. The apparatus as set forth in claim 30, wherein emissions of oxides of nitrogen (Nox) are 9.7 parts per million by volume, or less, corrected to 15% oxygen. 34. The apparatus as set forth in claim 30, wherein emissions of oxides of nitrogen (Nox) are 6.72 parts per million by volume, or less, corrected to 15% oxygen. 35. The apparatus as set forth in claim 30, wherein emissions of oxides of nitrogen (Nox) are 5.85 parts per million by volume, or less, corrected to 15% oxygen. 36. The apparatus as set forth in claim 30, wherein emissions of carbon monoxide are equal to 9.0 parts per million by volume, or less, corrected to 15% oxygen. 37. The apparatus as set forth in claim 1, wherein said fuel injectors comprise pilot fuel injectors. 38. The apparatus as set forth in claim 1, further comprising one or more air injectors, and wherein at least one of said one or more air injectors are oriented to provide a jet in opposition to said bulk fluid swirl predetermined direction. 39. The apparatus as set forth in claim 1, wherein emissions of oxides of nitrogen (Nox) are 9.70 parts per million by volume, or less, corrected to 15% oxygen. 40. The apparatus as set forth in claim 1, wherein emissions of oxides of nitrogen (Nox) are 6.72 parts per million by volume, or less, corrected to 15% oxygen. 41. The apparatus as set forth in claim 1, wherein emissions of oxides of nitrogen (Nox) are 5.85 parts per million by volume, or less, corrected to 15% oxygen. 42. The apparatus as set forth in claim 1, wherein emissions of carbon monoxide are 50.5 parts per million by volume, or less, corrected to 15% oxygen. 43. The apparatus as set forth in claim 1, wherein emissions of carbon monoxide are 14.3 parts per million by volume, or less, corrected to 15% oxygen. 44. The apparatus as set forth in claim 1, wherein emissions of carbon monoxide are 9.0 parts per million by volume, or less, corrected to 15% oxygen. 45. A method of operating a trapped vortex combustor, said method comprising: (a) providing a trapped vortex combustor, said trapped vortex combustor comprising: (1) one or more trapped vortex cavities, said one of said one or more trapped vortex cavities configured to provide a bulk fluid swirl in a predetermined direction; (2) an air supply system to supply inlet air; (3) a fuel supply system for the supply of gaseous fuel, said fuel supply system comprising (i) a premix stage wherein fuel from said fuel supply system is mixed with said inlet air to provide a lean pre-mixture upstream of a first one of said one or more trapped vortex cavities; and (ii) at least one fuel stage comprising one or more injectors in fluid communication with said fuel supply system, at least one of said one or more injectors configured to inject fuel into a first one of said one or more trapped vortex cavities; (b) injecting fuel through at least one of said one or more injectors that is configured to inject fuel into said first one of said one or more trapped vortex cavities in an fluid injection direction oriented to provide a jet from said at least one of said one or more injectors, to provide momentum of injected fuel in opposition to said bulk fluid swirl predetermined direction. 46. The method as set forth in claim 45, wherein said trapped vortex combustor further comprises one or more air injectors, and wherein said method further comprises the step of injecting air through at least one of said one or more air injectors to provide momentum of injected air in opposition to said bulk fluid swirl predetermined direction. 47. The method as set forth in claim 45, wherein said trapped vortex combustor comprises a combustor in a gas turbine engine. 48. The method as set forth in claim 45, wherein emissions of oxides of nitrogen (NOx) are 20 parts per million by volume, or less, corrected to 15% oxygen. 49. The method as set forth in claim 45, wherein emissions of oxides of nitrogen (NOx) are 10 parts per million by volume, or less, corrected to 15% oxygen. 50. The method as set forth in claim 45, wherein emissions of oxides of nitrogen (NOx) are 9.70 parts per million by volume, or less, corrected to 15% oxygen. 51. The method as set forth in claim 45, wherein emissions of oxides of nitrogen (NOx) are 6.72 parts per million by volume, or less, corrected to 15% oxygen. 52. The method as set forth in claim 45, wherein emissions of oxides of nitrogen (NOx) are 5.85 parts per million by volume, or less, corrected to 15% oxygen. 53. The method as set forth in claim 45, wherein emissions of carbon monoxide are 20 parts per million by volume, or less, corrected to 15% oxygen. 54. The method as set forth in claim 45, wherein emissions of carbon monoxide are 10 parts per million by volume, or less, corrected to 15% oxygen. 55. The method as set forth in claim 45, wherein (a) emissions of oxides of nitrogen (NOx) are 10 parts per million by volume, or less, corrected to 15% oxygen, and (b) emissions of carbon monoxide are 10 parts per million by volume, or less, corrected to 15% oxygen. 56. The method as set forth in claim 45, or in claim 55, wherein emissions of oxides of nitrogen (NOx) are 9.7 parts per million by volume, or less, corrected to 15% oxygen. 57. The method as set forth in claim 45, or in claim 55, wherein emissions of carbon monoxide are 9.0 parts per million by volume, or less, corrected to 15% oxygen.