Claims
- 1. An engine assembly comprising:
a gas turbine engine producing an exhaust flow; and an afterburner apparatus coupled to the gas turbine engine, the afterburner apparatus including a burner and a swirl generator, the burner having a burner inlet, the swirl generator having an inlet housing, a swirl vane pack, a centerbody assembly, and a plurality of fuel injectors, the inlet housing being coupled to the burner inlet, the inlet housing defining a hollow interior volume therein and serving as a conduit through which at least a portion of the exhaust flow is conducted, the hollow interior volume intersecting the burner inlet at a dump step wherein the inlet housing has an inner dimension that is smaller than that of the burner inlet, the swirl vane pack being disposed within the hollow interior volume and having a plurality of vanes, the vanes cooperating to change the velocity of the exhaust flow so that its velocity includes a substantial tangential velocity component, the centerbody assembly being coupled to the swirl vane pack and extending rearwardly therefrom, the plurality of fuel injectors being coupled to at least one of the inlet housing, the swirl vane pack and the centerbody assembly and dispensing a fuel therefrom; wherein the swirl generator converts the exhaust flow received therein into a swirling, three-dimensional flowfield; wherein a first portion of the flowfield flows over the dump step to form an outer recirculation zone; wherein a second portion of the flowfield forms a central recirculation zone that is anchored by an aft end of the centerbody assembly; wherein a first portion of the fuel mixes with the first portion of the flowfield to fuel the outer recirculation zone; wherein a second portion of the fuel mixes with the second portion of the flowfield to fuel the central recirculation zone; and wherein a remaining portion of the fuel enters and fuels a core flow.
- 2. The engine assembly of claim 1, wherein at least a portion of the fuel injectors are positioned to inject the fuel downstream of the swirl vane pack.
- 3. The engine assembly of claim 1, wherein at least one of the fuel injectors is housed in the centerbody assembly.
- 4. The engine assembly of claim 3, wherein the centerbody assembly includes at least one injection ring, the injection ring including a plurality of fuel injection sites that are spaced apart about a perimeter of the injection ring.
- 5. The engine assembly of claim 3, wherein the at least one of the fuel injectors is coupled to an aft end of the centerbody assembly and is configured to inject fuel in a direction downstream of the centerbody assembly.
- 6. The engine assembly of claim 1, wherein the plurality of fuel injectors include a plurality of fuel injection sites that are formed into at least a portion of the vanes of the swirl vane pack.
- 7. The engine assembly of claim 6, wherein each vane includes a trailing edge and a lateral surface and wherein the fuel injection sites on a given vane are formed into at least one of the trailing edge and the lateral surface.
- 8. The engine assembly of claim 1, wherein the centerbody assembly terminates at an aft bluff boat-tail body, the aft bluff boat-tail body being configured to augment flow separation of the exhaust flow.
- 9. The engine assembly of claim 8, wherein the centerbody assembly includes an extendable centerbody cone.
- 10. The engine assembly of claim 1, wherein the vanes of the swirl vane pack are selectively positionable at a first position and a second position.
- 11. The engine assembly of claim 10, wherein the vanes are further selectively positionable to at least one position between the first and second positions.
- 12. The engine assembly of claim 10, wherein the first position is an orientation of 0° so as not to swirl the exhaust flow when the afterburner apparatus is not being employed.
- 13. The engine assembly of claim 10, wherein the second position is a non-zero orientation of the vanes that causes the exhaust flow to swirl.
- 14. The engine assembly of claim 10, wherein the vanes have a flat profile.
- 15. The engine assembly of claim 1, wherein the swirl generator further comprises at least one igniter, the igniter being coupled to one of the centerbody assembly, the inlet housing and the burner, the igniter being operable for generating an ignition kernel that ignites the fuel/oxidizer mixture in the central recirculation zone.
- 16. The engine assembly of claim 15, wherein the igniter is housed in the centerbody assembly.
- 17. The engine assembly of claim 16, further comprising a second igniter coupled to the burner at a location downstream of the dump step.
- 18. The engine assembly of claim 15, wherein the igniter is selected from a group of igniters consisting of spark igniters, plasma jet igniters, laser-based igniters and microwave based igniters.
- 19. The engine assembly of claim 1, wherein the inlet of the burner includes a quarl expansion.
- 20. The engine assembly of claim 1, wherein an inlet ramp is formed onto the inlet housing adjacent the dump step.
- 21. The engine assembly of claim 20, wherein a plurality of circumferentially spaced apart injection sites are formed into the inlet ramp, the injection sites comprising at least a portion of the fuel injectors.
- 22. The engine assembly of claim 1, wherein the vanes are configured to provide the swirl vane pack with a swirl number that is less than about 2.0.
- 23. The engine assembly of claim 22, wherein the swirl number of the swirl vane pack is about 0.4 to about 1.2.
- 24. The engine assembly of claim 1, wherein the gas turbine engine is selected from a group consisting of turbojet engines and turbofan engines.
- 25. The engine assembly of claim 1, further comprising a variable area nozzle associated with the burner.
- 26. The engine assembly of claim 1, wherein the burner is an expanding burner.
- 27. An afterburner apparatus comprising:
an expanding burner having an inlet; a swirl generator that is coupled to the inlet of the burner, the swirl generator being operable for converting an oxidizer flow into a three-dimensional flowfield that includes a substantial tangential velocity component, the swirl generator including a flow defining means and a fueling means, the flow defining means being operable for effecting both an outer recirculation zone and a central recirculation zone in the combustor, the outer recirculation zone being toroidal in shape, the central recirculation zone being disposed inwardly of the outer recirculation zone, the fueling means being operable for fueling the outer and central recirculation zones; wherein heat and combustion byproducts produced during combustion are carried upstream by the outer and central recirculation zones where the heat and combustion byproducts are employed to continuously ignite a combustible fuel/oxidizer mixture in a shear layer adjacent each of the outer and central recirculation zones.
- 28. The afterburner apparatus of claim 27, further comprising a variable area nozzle associated with the burner.
- 29. The afterburner apparatus of claim 27, wherein the flow defining means includes a swirl vane pack having a plurality of vanes and wherein the vanes are configured to selectively provide the swirl vane pack with a swirl number that is less than about 2.0.
- 30. The afterburner apparatus of claim 29, wherein the swirl number of the swirl vane pack is about 0.4 to about 1.2.
- 31. The afterburner apparatus of claim 29, wherein the vanes have a flat profile.
- 32. The afterburner apparatus of claim 27, wherein the plurality of fuel injectors include a plurality of fuel injection sites that are formed into at least a portion of the vanes of the swirl vane pack.
- 33. The afterburner apparatus of claim 32, wherein each vane includes a trailing edge and a lateral surface and wherein the fuel injection sites on a given vane are formed into at least one of the trailing edge and the lateral surface.
- 34. The afterburner apparatus of claim 27, wherein the centerbody assembly includes an extendable centerbody cone.
- 35. The afterburner apparatus of claim 27, wherein the inlet of the burner includes a quarl expansion.
- 36. The afterburner apparatus of claim 27, wherein an inlet ramp is formed onto the inlet housing adjacent the dump step.
- 37. The afterburner apparatus of claim 36, wherein a plurality of circumferentially spaced apart injection sites are formed into the inlet ramp, the injection sites comprising at least a portion of the fuel injectors.
- 38. An apparatus for providing propulsive power comprising:
a gas turbine engine producing an exhaust flow; and an afterburner apparatus having a burner, a swirl generator and a variable area nozzle, the swirl generator being associated with an aft end of the gas turbine engine, the swirl generator including a flow affecting means and a fueling means, the flow affecting means including a plurality of vanes, a centerbody having an aft end that terminates rearwardly of a root of the vanes and, a dump step, the flow affecting means being operable for converting the exhaust flow into a three dimensional flowfield that includes a substantial tangential velocity component, the flow affecting means being further operable for effecting both a toroidal outer recirculation zone, which is anchored by the dump step, and a central recirculation zone that is disposed inwardly of the outer recirculation zone and anchored by the aft end of the centerbody, the fueling means being operable for fueling the outer and central recirculation zones and a core flow, the burner being associated with an aft end of the swirl generator, the variable area nozzle being associated with an aft end of the burner; wherein heat and combustion byproducts produced during combustion are carried upstream by the outer and central recirculation zones where the heat and combustion byproducts are employed to continuously ignite a combustible fuel/oxidizer mixture in a shear layer adjacent each of the outer and central recirculation zones; and wherein combustion by-products from the core flow are expelled through the variable area nozzle to produce thrust.
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. application Ser. No. 10/243,961, filed Sep. 13, 2002 entitled “Compact, Lightweight High-Performance Lift Thruster Incorporating Swirl-Augmented Oxidizer/Fuel Injection Mixing and Combustion”. Other features of the present invention are discussed and claimed in copending U.S. Application Serial No. ______ entitled “Compact Lightweight Ramjet Engines Incorporating Swirl Augmented Combustion With Improved Performance and in copending U.S. Application Ser. No. ______ entitled “Combined Cycle Engines Incorporating Swirl Augmented Combustion for Reduced Volume and Weight and Improved Performance”.
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
10243961 |
Sep 2002 |
US |
Child |
10360016 |
Feb 2003 |
US |