Aft frame with oval-shaped cooling slots and related method

Abstract

An aft frame adapted to interface between a combustor transition piece and a first stage turbine nozzle includes: a closed-periphery frame comprised of a top, bottom and pair of side walls. A plurality of cooling holes or apertures having elliptical or oval cross-sectional shapes are provided in one or more of the top, bottom and pair of side walls, extending axially through the closed-periphery frame. The cooling holes have major and minor axes arranged such that the major axes are substantially parallel with the top and bottom walls.

1 . An aft frame adapted to interface between a combustor transition piece and a first stage turbine nozzle comprising:
 a closed-periphery frame comprised of a top, bottom and pair of side walls; and a plurality of cooling apertures extending through one or more of said top, bottom and pair of side walls, said plurality of cooling apertures having an elliptical or oval cross-sectional shape.   
   
   
       2 . The aft frame of  claim 1  wherein one or more of said plurality of cooling apertures are provided in each of said top, bottom and pair of side walls. 
   
   
       3 . The aft frame of  claim 1  wherein said plurality of cooling apertures extend in an axial direction through said closed-periphery frame. 
   
   
       4 . The aft frame of  claim 2  wherein said plurality of cooling apertures extend in an axial direction through said closed-periphery frame. 
   
   
       5 . The aft frame of  claim 1  wherein said plurality of cooling apertures have major and minor axes, arranged with said major axes substantially parallel with said top and bottom walls. 
   
   
       6 . The aft frame of  claim 4  wherein said plurality of cooling apertures have major and minor axes, arranged with said major axes substantially parallel with said top and bottom walls. 
   
   
       7 . An aft frame adapted to interface between a combustor transition piece and a first stage turbine nozzle comprising:
 a closed-periphery frame comprised of a top, bottom and pair of side walls; and a plurality of cooling apertures having elliptical or oval cross-sectional shapes provided in each of said top, bottom and pair of side walls, extending axially through said closed-periphery frame; and   wherein said plurality of cooling apertures have major and minor axes, arranged such that said major axes are substantially parallel with said top and bottom walls.   
   
   
       8 . A method of forming a turbine aft frame adapted to interface between a combustor transition piece and a first stage turbine nozzle comprising:
 a) providing a closed periphery aft frame having top and bottom walls and a pair of side walls, and   b) forming elliptically-shaped cooling holes in at least one of said top, bottom and pair of side walls, extending axially through the aft frame.   
   
   
       9 . The method of  claim 8  including providing said elliptically-shaped cooling holes in all of said top, bottom and pair of side walls. 
   
   
       10 . The method of  claim 8  wherein said elliptically-shaped cooling holes have major and minor axes, and wherein step b) includes arranging said elliptically-shaped cooling holes with said major axes substantially parallel to said top and bottom walls.