Apparatus for reducing a temperature gradient of mainstream fluid downstream of an airfoil in a gas turbine engine

Abstract

An apparatus ( 100 ) is presented for reducing a temperature gradient ( 30 ) of mainstream fluid ( 118 ) downstream of an airfoil ( 112 ) in a gas turbine engine ( 110 ). The apparatus includes a passage ( 116 ) in a trailing edge ( 114 ) of the airfoil having an inlet ( 132 ) and an outlet ( 134 ). The apparatus also includes a cooling fluid source ( 136 ) coupled to the inlet to transmit cooling fluid into the passage. The apparatus also includes a vortex generator ( 138 ) within the passage effective to generate a vortex fluid ( 140 ) at the outlet. The outlet is positioned to inject the vortex fluid into the mainstream fluid with sufficient mixing energy to cause a reduced temperature gradient ( 130 ) downstream of the airfoil.

The invention claimed is: 
     
         1 . An airfoil of a gas turbine engine comprising:
 a root section;   an airfoil section comprising a trailing edge connected to the root section;   a cooling fluid passage in the trailing edge; and   a vortex generator within the trailing edge cooling fluid passage effective to generate vorticity in cooling fluid that is ejected from the passage.   
     
     
         2 . The airfoil of  claim 1 , wherein the vorticity is effective to reduce a temperature gradient downstream of the airfoil. 
     
     
         3 . The airfoil of  claim 1 , wherein the vortex generator comprises a swirler inserted within an outlet of the passage. 
     
     
         4 . The airfoil of  claim 1 , wherein the vortex generator comprises a plurality of swirler channels within the passage, and wherein said swirler channels are positioned in an outer portion of the passage. 
     
     
         5 . The airfoil of  claim 4 , wherein the vortex generator further comprises a solid core within a central portion of the passage, wherein the swirler channels are disposed about the solid core such that said solid core is configured to redirect fluid from the central portion into the swirler channels. 
     
     
         6 . The airfoil of  claim 4 , wherein the vortex generator further comprises a hollow core within a central portion of the passage, and wherein the swirler channels are disposed about the hollow core. 
     
     
         7 . The airfoil of  claim 1 , further comprising a plurality of cooling fluid passages in the trailing edge and a respective vortex generator in each passage, wherein adjacent vortex generators are configured to rotate the cooling fluid from adjacent passage outlets with a vorticity in opposite directions. 
     
     
         8 . An airfoil for a gas turbine engine wherein an improvement comprises:
 a passage in a trailing edge of the airfoil, said passage including an inlet and an outlet, said passage configured to receive cooling fluid in the inlet and further configured to generate a vortex fluid at the outlet;   wherein when said vortex fluid is injected into a mainstream fluid passing over the airfoil, the vortex fluid will mix with the mainstream fluid.   
     
     
         9 . The airfoil of  claim 8 , wherein the passage is configured such that the injected vortex fluid will mix with the mainstream fluid such that a temperature gradient of the mainstream fluid is reduced downstream of the airfoil. 
     
     
         10 . The airfoil of  claim 8 , wherein said passage is configured to receive the cooling fluid from a serpentine cooling fluid network of the airfoil positioned upstream in the cooling fluid from the passage in the trailing edge. 
     
     
         11 . The airfoil of  claim 8 , wherein said passage includes at least one swirler channel configured to generate a vorticity of the vortex fluid to be injected from the outlet into the mainstream fluid. 
     
     
         12 . An airfoil for injecting a vortex fluid into a mainstream fluid passing over the airfoil, said airfoil comprising:
 a trailing edge of the airfoil; and   a vortex generator having an outlet in the trailing edge for injecting the vortex fluid into the mainstream fluid.   
     
     
         13 . The airfoil of  claim 12 , wherein a plurality of outlets in the trailing edge and a respective vortex generator in each outlet are configured to generate a respective vortex fluid exiting each outlet, wherein the adjacent vortex generators are configured to rotate the vortex fluid from adjacent outlets with a vorticity in a same direction. 
     
     
         14 . The airfoil of  claim 12 , wherein a plurality of outlets in the trailing edge and a respective vortex generator in each outlet are configured to generate a respective vortex fluid exiting each outlet, wherein the adjacent vortex generators are configured to rotate the vortex fluid from adjacent outlets with a vorticity in an opposite direction. 
     
     
         15 . The airfoil of  claim 12 , further comprising a passage within the trailing edge, wherein said vortex generator is positioned within the passage, wherein said vortex generator includes at least one swirler channel to generate the vortex fluid at the outlet and wherein said vortex fluid is effective to generate a secondary vorticity in the mainstream fluid. 
     
     
         16 . The airfoil of  claim 15 , wherein the vortex generator further comprises a solid core within a central portion of the passage, and wherein the vortex generator includes a plurality of swirler channels disposed about the solid core such that said solid core is configured to redirect fluid from the central portion into the swirler channels to generate the vortex in the cooling fluid exiting the outlet. 
     
     
         17 . The airfoil of  claim 15 , wherein the vortex generator further comprises a hollow core within a central portion of the passage, wherein the vortex generator further comprises a plurality of swirler channels, and wherein the swirler channels are disposed about the hollow core.