EXHAUST STREAM MIXER

• US 20180187629A1
• Filed: 02/27/2018
• Published: 07/05/2018
• Est. Priority Date: 06/07/2013
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Granted Patent: US 10,641,205 B2
• Time in Patent Office: Days
• CPC Class Codes: B64D 2027/005 Aircraft with an unducted turbofan comprising contra-rotating rotors, e.g. contra-rotating open rotors [CROR]
• CPC Class Codes: B64D 33/04 of exhaust outlets or jet pipes exhaust outlets for combustion engines in general F01N; jet pipes or nozzles for jet-propulsion plants per se F02K; plants characterised by the form or arrangement of the jet pipe or nozzle F02K ; attitude, flight direction, or altitude control by jet reaction B64C
• CPC Class Codes: F02K 1/386 mixing devices in the jet pipe, e.g. for mixing primary and secondary flow
• CPC Class Codes: F02K 1/48 Corrugated nozzles
• CPC Class Codes: F02K 3/062 with aft fan
• CPC Class Codes: F05D 2240/127 Vortex generators, turbulators, or the like, for mixing by creating turbulence F05D2260/2212
• CPC Class Codes: F05D 2260/2212 by creating turbulence vortex generators, turbulators or the like for mixing F05D2240/127
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

An exhaust nozzle for a turbine engine includes multiple daisy style corrugations arranged circumferentially about the exhaust nozzle. Each of the daisy style corrugations has a radially inner base portion and multiple lobes protruding radially outward from the base portion.

Claims

1. A method for mixing exhaust gas exiting an exhaust nozzle of a turbine engine comprising the step of:

passing exhaust gasses through an exhaust stream mixer thereby generating stream-wise vortices and transverse vortices in said exhaust stream, wherein said exhaust stream mixer comprises at least one daisy style corrugation, the exhaust stream mixer is defined by a cross section normal to an axis defined by the turbine engine, wherein the cross section has a length extending the entire circumference of the cross section at least twice a length along a circumference of a circle inscribing the cross section normal to the axis of the corresponding stream mixer of each of said plurality of exhaust stream mixers.

2. The method of claim 1, wherein said step of passing said exhaust gasses through an exhaust stream mixer, comprises passing said gas through an exhaust stream mixer defined by at least a base portion having two convex walls and a plurality of lobes extending radially outward from said base portion, thereby maximizing a circumference of said exhaust nozzle while maintaining a desired cross sectional area.

3. The method of claim 1, wherein the step of passing said exhaust gasses through said exhaust stream mixer further comprises maturing the vortices until said vortices are of sufficient size that each of said vortices interfaces with adjacent vortices.

4. The method of claim 1, wherein said stream-wise vortices and said transverse vortices facilitate intermixing between said exhaust gasses and a surrounding ambient air flow.

5. The method of claim 4, wherein said intermixing between said exhaust gasses and said surrounding ambient air flow cools said exhaust gasses prior to said exhaust gasses contacting a propeller blade, thereby protecting said propeller blade from thermal stresses.

6. A turbine engine comprising:

a compressor section;

a combustor in fluid communication with the compressor section;

a turbine section in fluid communication with the combustor,

an exhaust nozzle in fluid communication with the turbine section;

said exhaust nozzle comprising a plurality of exhaust stream mixers circumferentially disposed about said exhaust nozzle, wherein each of said exhaust stream mixers includes a radially inward base portion and a plurality lobes protruding radially outward from said base portion, and the exhaust stream mixer is defined by a cross section normal to an axis defined by the turbine engine, wherein the cross section has a length extending the entire circumference of the cross section at least twice a length along a circumference of a circle inscribing the cross section normal to the axis of the corresponding stream mixer of each of said plurality of exhaust stream mixers.

7. The turbine engine of claim 6, wherein each of said exhaust stream mixers is defined by a single continuously curved wall.

8. The turbine engine of claim 6, wherein each of said exhaust stream mixers is further defined by a cross section normal to an defined by the turbine engine, wherein the cross section has a circumferential length at least twice the circumferential length of a circle inscribing the exhaust stream mixer.

9. The turbine engine of claim 6, wherein each of said base portions is defined by a pair of convex walls.

10. The turbine engine of claim 6, wherein further comprising at least four exhaust stream mixers.

11. The turbine engine of claim 10, further comprising at least 8 exhaust stream mixers.

12. The turbine engine of claim 6, wherein each of said exhaust stream mixers has a radial height less than one half the total radius of the exhaust nozzle.

13. The turbine engine of claim 12, wherein each of said exhaust stream mixers has a radial height of less than one quarter the total radius of the exhaust nozzle.

14. The turbine engine of claim 6, wherein each of said exhaust stream mixers is defined by at least three radially protruding lobes and a valley between each of said radially protruding lobes and each adjacent of said radially protruding lobes.

15. The turbine engine of claim 6, wherein each of said lobes has a smaller cross sectional area than said base portion.

16. An exhaust nozzle comprising:

an axis defined by the exhaust nozzle, wherein a cross section of the exhaust nozzle normal to said axis includes a plurality of daisy style corrugations;

each of said daisy style corrugations further comprises a radially inner base portion, and a plurality of lobes protruding radially outward from said base portion; and

each of said daisy style corrugations is defined by a cross section normal to an axis defined by a turbine engine, wherein the cross section has a length extending the entire circumference of the cross section at least twice a length along a circumference of a circle inscribing the cross section normal to the axis of the corresponding stream mixer of each of said plurality of exhaust stream mixers.

17. The exhaust nozzle of claim 16, wherein each of said daisy style corrugations is defined by a plurality of convex sidewalls.

18. The exhaust nozzle of claim 17, wherein each of said plurality of lobes has a smaller cross sectional area than said base section.

19. The exhaust nozzle of claim 17, wherein said daisy style corrugation is constructed of a single continuous wall.