Cooled turbine nozzle segment

Abstract

A turbine nozzle segment may have a band having a flange extending radially from a non-flowpath side and an aft end. A plurality of airfoils may extend radially from a flowpath side of the band and may have trailing edges. A plurality of cooling holes may be disposed in the flange and directed at the aft end between the trailing edges.

1 . A turbine nozzle segment comprising:
 a band having a flowpath side, a non-flowpath side, a flange extending radially from said non-flowpath side and an aft end;   a plurality of airfoils extending radially from said flowpath side, said airfoils having trailing edges; and   a plurality of cooling holes disposed in said flange, said cooling holes directed at said aft end of said non-flowpath side of said band between said trailing edges.   
   
   
       2 . The turbine nozzle segment of  claim 1  wherein said cooling holes are directed so as to impinge upon said aft end of said non-flowpath side of said band. 
   
   
       3 . The turbine nozzle segment of  claim 1  wherein said cooling holes have a compound angle relative to a line parallel to the engine centerline. 
   
   
       4 . The turbine nozzle segment of  claim 3  wherein said cooling holes have a first angle measured in the radial plane relative to a line parallel to the engine centerline between about 10 degrees and about 75 degrees. 
   
   
       5 . The turbine nozzle segment of  claim 4  wherein said cooling holes have a second angle measured in the circumferential plane relative to a line parallel to the engine centerline between about 10 degrees and about 80 degrees. 
   
   
       6 . The turbine nozzle segment of  claim 1  wherein said cooling holes have a first angle measured in the radial plane relative to a line parallel to the engine centerline between about 10 degrees and about 75 degrees. 
   
   
       7 . The turbine nozzle segment of  claim 1  wherein said cooling holes have a second angle measured in the circumferential plane relative to a line parallel to the engine centerline between about 10 degrees and about 80 degrees. 
   
   
       8 . The turbine nozzle segment of  claim 1  further comprising a thermal barrier coating applied to said aft end of said flowpath side of said band between said airfoil trailing edges. 
   
   
       9 . The turbine nozzle segment of  claim 1  wherein said flange is located near said aft end. 
   
   
       10 . The turbine nozzle segment of  claim 1  further comprising:
 a plenum on said non-flowpath side of said band for providing cooling air to said plurality of cooling holes.   
   
   
       11 . A turbine nozzle assembly comprising:
 a plurality of arcuate turbine nozzle segments joined together to form an annular ring; said plurality of arcuate segments each comprising:
 a band having a flowpath side, a non-flowpath side, a flange extending radially from said non-flowpath side and an aft end; 
 a plurality of airfoils extending radially from said flowpath side, said airfoils having trailing edges; and 
 a plurality of cooling holes disposed in said flange, said cooling holes directed at said aft end of said non-flowpath side of said band between said trailing edges. 
   
   
   
       12 . The turbine nozzle assembly of  claim 11  wherein said cooling holes are directed so as to impinge upon said aft end of said non-flowpath side of said band. 
   
   
       13 . The turbine nozzle assembly of  claim 11  wherein said cooling holes have a compound angle relative to a line parallel to the engine centerline. 
   
   
       14 . The turbine nozzle assembly of  claim 13  wherein said cooling holes have a first angle measured in the radial plane relative to a line parallel to the engine centerline between about 10 degrees and about 75 degrees. 
   
   
       15 . The turbine nozzle assembly of  claim 14  wherein said cooling holes have a second angle measured in the circumferential plane relative to a line parallel to the engine centerline between about 10 degrees and about 80 degrees. 
   
   
       16 . The turbine nozzle assembly of  claim 11  wherein said cooling holes have a first angle measured in the radial plane relative to a line parallel to the engine centerline between about 10 degrees and about 75 degrees. 
   
   
       17 . The turbine nozzle assembly of  claim 11  wherein said cooling holes have a second angle measured in the circumferential plane relative to a line parallel to the engine centerline between about 10 degrees and about 80 degrees. 
   
   
       18 . The turbine nozzle assembly of  claim 11  further comprising a thermal barrier coating applied to said aft end of said flowpath side of said band between said airfoil trailing edges. 
   
   
       19 . The turbine nozzle assembly of  claim 11  wherein said flange is located near said aft end. 
   
   
       20 . The turbine nozzle assembly of  claim 11  further comprising:
 a plenum on said non-flowpath side of said band for providing cooling air to said plurality of cooling holes.