Gas turbine mixer apparatus
First Claim
1. Mixing apparatus for mixing first and second fluid streams with one another wherein said first fluid stream flows through an inner duct and said second fluid stream flows through an annular passageway formed between said inner duct and an outer duct that coaxially surrounds said inner duct, the direction of fluid flow of said first and second fluid streams substantially being in the same axial direction relative to said coaxially arranged inner and outer ducts, said outer duct extending axially in the direction of fluid flow beyond the terminus of said inner duct to define a common duct for the mixing of said first and second fluid streams, said mixing apparatus comprising:
- an annular free mixer mountable to said terminus of said inner duct to extend in said axial direction of fluid flow, said annular free mixer having a cross-sectional geometry at the forwardmost end thereof substantially corresponding to the cross-sectional geometry of said terminus of said inner duct, said annular free mixer having a smoothly contoured terminating edge for permitting those regions in said first and second fluid streams flowing contiguous with the boundaries of said free mixer to partially mix with one another as said contiguous regions flow past said terminating edge of said free mixer;
a plurality of axially extending members projecting rearwardly from said terminating edge of said free mixer, said plurality of axially extending members being circumferentially spaced-apart from one another along said terminating edge of said annular free mixer, said plurality of axially extending members defining a plurality of axially extending open regions between adjacent ones of said axially extending members, said plurality of axially extending members being configured and arranged to define the transverse cross-sectional geometry of said plurality of open regions as segments between two concentric, geometric closed curves with each of said axially extending members forming a boundary wall that separates one of said open regions from an adjacent one of said open regions to thereby collectively define said plurality of open regions;
means for inducing a component of outward radial flow of said first fluid stream through a first plurality of said axially extending open regions and for inducing a component of inward radial flow of said second fluid stream through a second plurality of said axially extending open regions, said radially induced flow of said first fluid stream penetrating into said second fluid stream and said radially induced flow of said second fluid stream penetrating into said first fluid stream, individual open regions of said first plurality of open regions for outward radial flow of said first fluid stream being interspersed in circumferential alternation with individual open regions of said second plurality of open regions for inward radial flow of said second fluid stream, said means for inducing said radial flow of said first and second fluid streams including a plurality of deflection vanes mounted transversely within individual open regions of at least one of said first and second pluralities of axially extending open regions, said plurality of deflection vanes mounted within said individual open regions to extend between adjacent ones of said circumferentially spaced-apart, axially extending members, said deflection vanes being spaced-apart from one another along said axially extending members and canted relative to the axial flow direction of said first and second fluid streams, said deflection vanes being canted to expose the forwardmost boundary of each of said deflection vanes with that one of said first and second fluid streams being induced to include a radial flow component.
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Accused Products
Abstract
Fluid mixing apparatus for mixing the coaxially flowing streams of fan air and primary exhaust within a turbofan engine are disclosed. Each of the disclosed arrangements include a generally tubular mixer section that extends axially rearward from the engine turbine flange. The mixing apparatus includes axially extending regions in which contiguous portions of the fan stream are induced to flow radially inward to penetrate the primary flowstream and includes axially extending regions in which contiguous portions of the primary flowstream are induced to flow radially outward to penetrate the fan stream. The regions inducing the outwardly directed flow of the primary flowstream and the regions inducing the inwardly directed flow of the fan stream are circumferentially interspersed with one another to establish a flow pattern which causes mixing to occur along the axial length of the mixing apparatus and causes mixing to continue within a common exhaust duct located aft of the mixing apparatus. In some of the disclosed arrangements, a series of deflection vanes are positioned across each of the regions that divert the fan flowstream and each of the regions that divert the primary flowstream. In other arrangements, only the regions for diverting fan flow or the regions for diverting primary flow include such deflection vanes. In each arrangement an annular free mixing boundary is formed along the forward portion of the mixing apparatus to minimize the effect of the mixer geometry on the engine cycle of the gas turbine engine in which the apparatus is employed.
126 Citations
12 Claims
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1. Mixing apparatus for mixing first and second fluid streams with one another wherein said first fluid stream flows through an inner duct and said second fluid stream flows through an annular passageway formed between said inner duct and an outer duct that coaxially surrounds said inner duct, the direction of fluid flow of said first and second fluid streams substantially being in the same axial direction relative to said coaxially arranged inner and outer ducts, said outer duct extending axially in the direction of fluid flow beyond the terminus of said inner duct to define a common duct for the mixing of said first and second fluid streams, said mixing apparatus comprising:
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an annular free mixer mountable to said terminus of said inner duct to extend in said axial direction of fluid flow, said annular free mixer having a cross-sectional geometry at the forwardmost end thereof substantially corresponding to the cross-sectional geometry of said terminus of said inner duct, said annular free mixer having a smoothly contoured terminating edge for permitting those regions in said first and second fluid streams flowing contiguous with the boundaries of said free mixer to partially mix with one another as said contiguous regions flow past said terminating edge of said free mixer; a plurality of axially extending members projecting rearwardly from said terminating edge of said free mixer, said plurality of axially extending members being circumferentially spaced-apart from one another along said terminating edge of said annular free mixer, said plurality of axially extending members defining a plurality of axially extending open regions between adjacent ones of said axially extending members, said plurality of axially extending members being configured and arranged to define the transverse cross-sectional geometry of said plurality of open regions as segments between two concentric, geometric closed curves with each of said axially extending members forming a boundary wall that separates one of said open regions from an adjacent one of said open regions to thereby collectively define said plurality of open regions; means for inducing a component of outward radial flow of said first fluid stream through a first plurality of said axially extending open regions and for inducing a component of inward radial flow of said second fluid stream through a second plurality of said axially extending open regions, said radially induced flow of said first fluid stream penetrating into said second fluid stream and said radially induced flow of said second fluid stream penetrating into said first fluid stream, individual open regions of said first plurality of open regions for outward radial flow of said first fluid stream being interspersed in circumferential alternation with individual open regions of said second plurality of open regions for inward radial flow of said second fluid stream, said means for inducing said radial flow of said first and second fluid streams including a plurality of deflection vanes mounted transversely within individual open regions of at least one of said first and second pluralities of axially extending open regions, said plurality of deflection vanes mounted within said individual open regions to extend between adjacent ones of said circumferentially spaced-apart, axially extending members, said deflection vanes being spaced-apart from one another along said axially extending members and canted relative to the axial flow direction of said first and second fluid streams, said deflection vanes being canted to expose the forwardmost boundary of each of said deflection vanes with that one of said first and second fluid streams being induced to include a radial flow component. - View Dependent Claims (2, 3, 4, 5)
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6. Mixer apparatus for use in combination with a gas turbine engine of the turbofan variety, said turbofan engine including a first fluid duct mounted coaxially within a second fluid duct, said second fluid duct extending rearwardly beyond the aft terminus of said first fluid duct to form a common exhaust duct wherein the primary fluid stream of said turbofan engine passes rearwardly through said first fluid duct and the secondary fluid stream of said turbofan engine passes into said common exhaust duct through the annular passage formed between said first and second fluid ducts, said primary and secondary fluid streams passing rearwardly through said common exhaust duct for discharge into the atmosphere, said mixer apparatus comprising:
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an annular free mixer defining a rearward extension of said first fluid duct, said annular free mixer having a smoothly contoured aft terminus for the free mixing of portions of said primary and secondary fluid streams flowing contiguous to the boundaries of said annular free mixer as said primary and secondary fluid streams flow rearwardly across said aft terminus of said free mixer; a plurality of support members mounted to extend rearwardly from said aft terminus of said free mixer, said support members being circumferentially spaced apart from one another around the periphery of said annular free mixer, said support members dividing at least a portion of said primary fluid stream and at least a portion of said secondary fluid stream into a plurality of first and second flow regions, each of said first flow regions including that portion of said primary fluid stream flowing in the intervening region between two adjacent ones of said spaced-apart support members, each of said second flow regions including that portion of said secondary fluid stream flowing in the intervening region between two adjacent ones of said spaced-apart support members, each of said support members including an inner and outer edge with the inner and outer edges of said support members being positioned coincident with first and second concentric circles relative to a transverse cross-sectional view of said mixer apparatus; and a plurality of deflection vanes mounted between adjacent ones of said spaced apart support members, each deflection vane of said plurality of deflection vanes mounted and arranged to intercept flow of one of said first and second flow regions to radially divert said intercepted flow into a region of the other one of said primary and secondary fluid streams that flow contiguous with said intervening region defining said intercepted fluid region, said intercepted fluid flow being radially diverted to effect flow displacement and vortical flow within said region of said other fluid stream flowing contiguous with said intervening region defining said intercepted fluid region, said flow displacement and said vortical flow for inducing radial flow within said fluid stream to mix said primary and secondary fluid streams with one another. - View Dependent Claims (7, 8, 9, 10, 11, 12)
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Specification