PILOT FUEL INJECTION FOR A WAVE ROTOR ENGINE

• US 20100018215A1
• Filed: 06/14/2007
• Published: 01/28/2010
• Est. Priority Date: 06/15/2006
• Status: Active Grant

• Current Assignee: Indiana University Research & Technology Corporation (Indiana University)
• Original Assignee: Indiana University Research & Technology Corporation (Indiana University)
• Inventors: Razi, Nalim, Pezhman, Akbari
• Granted Patent: US 8,443,583 B2
• Time in Patent Office: Days
• US Class Current: 60/773
• CPC Class Codes: F02C 5/04 the combustion chambers being formed at least partly in the turbine rotor
• CPC Class Codes: F02C 7/222 Fuel flow conduits, e.g. manifolds
• CPC Class Codes: F02C 7/266 Electric sparking plugs H01T
• CPC Class Codes: F23N 1/02 conjointly with air supply
• CPC Class Codes: F23R 7/00 Intermittent or explosive combustion chambers

Abstract

Apparatus and methods for combustion of fuel. Some embodiments of the inventions include a fuel nozzle which injects fuel into a combustion channel of a wave rotor combustor or a pulse detonation combustor In some embodiments the combustion process includes a backward-propagating detonation wave within a substantially closed channel which compresses discrete quantities of combustible and noncombustible mixture. Yet other embodiments include a precombustion chamber integrated into the wave rotor, the outlet stator or both.

Claims

12-20. -20. (canceled)

21. A method for generating hot gas, comprising:

providing an enclosed channel interconnecting a first port with a second port;

flowing a first discrete quantity of a fuel and oxidizer mixture for combustion into a first port of the channel;

flowing the first discrete quantity in the channel toward the second port;

creating a second region of combustible mixture in the channel proximate to the second port by flowing fuel into the channel; and

igniting the second region prior to combusting the first quantity.

22. The method of claim 21 which further comprises igniting the first quantity with the combusted second region.

23. The method of claim 22 which further comprises flowing the first discrete quantity in the channel toward the second port and flowing a third quantity of oxidizer into the first port after said flowing the first quantity, and compressing the third quantity by the combustion of the first quantity.

24. The method of claim 23 wherein the third quantity is air substantially without any fuel mixed therein.

25. The method of claim 21 which further comprises substantially obstructing flow out of the second port prior to said igniting the second region.

26. The method of claim 21 which further comprises substantially obstructing the first port prior after said igniting the first quantity.

27. The method of claim 22 which further comprises exhausting the combusted second mixture and the combusted first mixture through the second port.

28. The method of claim 21 wherein the second region is created within a portion of the first discrete quantity that is proximate to the second port.

29. The method of claim 21 wherein said creating a second region includes injecting fuel from a pilot nozzle.

30. The method of claim 21 wherein said creating a second region is by injecting fuel into a portion of the first quantity that is proximate to the second port.

31. The method of claim 21 wherein said igniting the second region is by an electrical spark.

32. The method of claim 21 which further comprises restricting the flow out of the second port with a rotatable turbine.

33. The method of claim 21 which further comprises restricting the flow out of the second port with a convergent nozzle.

34. The method of claim 21 wherein said providing includes a plurality of channels, each channel interconnecting respective first and second ports.

35. The method of claim 34 wherein said plurality of channels are arranged in a rotor that is rotatable about an axis.

36. The method of claim 34 wherein said plurality of channels are arranged in a non-rotating housing.

37. The method of claim 21 wherein the first quantity comprises air and fuel in a first fuel/air ratio, the second region comprises air and fuel in a second fuel/air ratio, and the second fuel/air ratio is greater than the first fuel/air ratio.

38. The method of claim 21 wherein the first discrete quantity requires a first ignition energy, and the second region requires a second ignition energy that is less than the first ignition energy.

39-45. -45. (canceled)

46. A method for repeatedly combusting fuel, comprising:

providing a combustion chamber;

continuously compressing a flow of air;

injecting fuel into the compressed gas to form a combustible mixture;

flowing a quantity of the combustible mixture into the combustion chamber; and

injecting a discrete quantity of fuel into the combustible mixture in the combustion chamber.

47. The method of claim 46 which further comprises igniting the discrete quantity of fuel after said injecting.

48. The method of claim 47 wherein each said injecting a discrete quantity is associated with a different said igniting.

49. The method of claim 47 which further comprises combusting the combustible mixture by said igniting.

50. The method of claim 46 wherein the combustion chamber rotates at a speed, and said injecting is synchronized to the rotational speed.

51. The method of claim 46 wherein said providing includes a compressor rotatable at a speed, and said injecting is synchronized to the rotational speed.

52. The method of claim 46 wherein said injecting is synchronized to said flowing.

53. The method of claim 46 wherein said providing includes two different combustible fuels, said injecting fuel is injecting one of the fuels, and said injecting a discrete quantity of fuel is injecting a discrete quantity of the other fuel.

54. The method of claim 53 wherein the other fuel is a hypergolic fuel.

66. The method of claim 49 wherein said combusting is forward-propagating.

67. The method of claim 49 wherein said combusting is backward-propagating.

55-60. -60. (canceled)

62-65. -65. (canceled)

68-71. -71. (canceled)

73-75. -75. (canceled)

76. A combustor for combusting a mixture of fuel and air, comprising:

a rotor having two ends and defining a plurality of enclosed channels, each said channel being adapted and configured to support combustion therein and having a first port at the first end of said rotor and a second port at the second end of said rotor, said rotor being rotatable about an axis;

a first stator proximate to the first end of said rotor, said first stator including at least one inlet adapted and configured to provide flow of the uncombusted mixture into the first port of a corresponding said channel as said first port rotates into flow communication with said inlet;

a second stator proximate to the second end of said rotor, said first stator including at least one outlet adapted and configured to receive flow of combusted mixture from a second port of a corresponding said channel as said second port rotates into flow communication with said outlet;

a precombustion chamber in fluid communication with the second port of at least one of said channels, said precombustion chamber having at least one partition separating at least a portion of said precombustion chamber from at least a portion of the one said channel; and

wherein combustion in said precombustion chamber ignites the mixture in the one said channel.

1. A combustor, comprising:

a first fuel nozzle for spraying fuel to create a mixture of fuel and oxidizer for combustion;

a rotor having two ends and defining a plurality of enclosed channels, each said channel being adapted and configured to support combustion therein and having a first port at the first end of said rotor and a second port at the second end of said rotor, said rotor being rotatable about an axis;

a first stator proximate to the first end of said rotor, said first stator including at least one inlet adapted and configured to provide flow of the mixture into the first port of a corresponding said channel as said first port rotates into flow communication with said inlet;

a second stator proximate to the second end of said rotor, said first stator including at least one outlet adapted and configured to receive flow of combusted mixture from a second port of a corresponding said channel as said second port rotates into flow communication with said outlet; and

a second fuel nozzle for introducing fuel into at least one said channel intermediate of the first port and the second port.

2. The combustor of claim 1 wherein combustion of the fuel from said fuel nozzle results in a backward-propagating detonation cycle within the corresponding channel.

3. The combustor of claim 1 wherein said fuel nozzle is placed proximate to the second port, and which further comprises means for igniting the fuel from said fuel nozzle.

4. The combustor of claim 1 wherein said first stator includes at least two said inlets, each said inlet being spaced apart from each other so as to align with respective spaced apart channels of said rotor.

5. The combustor of claim 4 wherein said inlets are equally spaced about the circumference of said rotor.

6. The combustor of claim 1 wherein said second stator includes at least two said outlets, each said outlets being spaced apart from each other so as to align with respective circumferentially spaced apart channels of said rotor.

7. The combustor of claim 6 wherein said outlets are equally spaced about the circumference of said rotor.

8. The combustor of claim 1 which further comprises a plurality of fuel nozzles, each said fuel nozzle introducing fuel into a different one of said channels intermediate of the first port and the second port of the respective channel.

9. The combustor of claim 8 which further comprises a plurality of stationary igniters, each said igniter being circumferentially spaced between adjacent fuel nozzles.

10. The combustor of claim 1 which further comprises an igniter for igniting fuel introduced from said fuel nozzle.

11. The combustor of claim 10 wherein said igniter is coupled to said second stator and in electrical communication with the second port of a corresponding channel as said rotor rotates, wherein ignition of the fuel results in a backward-propagating detonation cycle within the corresponding channel.

61. The combustor of claim 1 wherein combustion of fuel from said fuel nozzle results in a forward-propagating detonation cycle within the corresponding channel.

72. The combustor of claim 6 which further comprises a plurality of fuel nozzles, each said fuel nozzle introducing fuel into one of said channels intermediate of the first port and the second port of the respective channel.

77. The combustor of claim 76 wherein said precombustion chamber is attached to said second stator.

78. The combustor of claim 77 wherein said precombustion chamber includes an inlet receiving gas from a second port of a different one of said channels and an outlet providing gas to the second port of the one said channel.

79. The combustor of claim 76 which further comprises a plurality of precombustion chambers, each said precombustion chamber being located within a corresponding one of said channels.

79-1. The combustor of claim 76 which further comprises a fuel nozzle for introducing fuel into said precombustion chamber.