Film starters in combustors of gas turbine engines

Abstract

A combustor liner, a combustor, and a gas turbine engine are provided. The combustor liner includes a liner portion having a plurality of dilution holes extending through the liner portion. Each dilution hole includes a downstream edge in a direction of a flow of a first fluid through the combustion liner. The downstream edge includes a film cooling starter device. The film cooling starter device includes a plurality of cooling holes extending through the liner portion and spaced apart from the downstream edge in a downstream direction. The film cooling starter device also includes a support flange extending from the downstream edge into the combustion zone, and a lip extending away from the support flange in the downstream direction and spaced a predetermined distance from a surface of the liner portion.

What is claimed is: 
     
         1 . A combustor liner at least partially surrounding a combustion zone, said combustor liner comprising:
 a liner portion;   a plurality of dilution holes extending through said liner portion, each of said dilution holes including a downstream edge in a direction of a flow of a first fluid through said combustor liner, said downstream edge including a film cooling starter device comprising:   a plurality of cooling holes extending through said liner portion and spaced apart from said downstream edge in a downstream direction;   a support flange extending from said downstream edge into the combustion zone; and   a lip extending away from said support flange in the downstream direction and spaced a predetermined distance from a surface of said liner portion.   
     
     
         2 . The combustor liner of  claim 1 , wherein said lip extends in the downstream direction over said plurality of cooling holes. 
     
     
         3 . The combustor liner of  claim 2 , wherein said plurality of dilution holes are configured to channel a flow of a second fluid in a second direction substantially perpendicular to the downstream direction. 
     
     
         4 . The combustor liner of  claim 3 , wherein said plurality of cooling holes is configured to channel a flow of a cooling fluid in the second direction. 
     
     
         5 . The combustor liner of  claim 4 , wherein said lip is configured to channel the flow of the cooling fluid in a third direction substantially parallel to the downstream direction. 
     
     
         6 . The combustor liner of  claim 5 , wherein said lip, said support flange, and combustor liner portion define a film initiation gap configured to channel the flow of the cooling fluid in the third direction. 
     
     
         7 . The combustor liner of  claim 6 , wherein the flow of the second fluid disrupts a flow of a cooling film along said surface of said liner portion, said film cooling starter device is configured to restart the flow of the cooling film downstream of a respective dilution hole. 
     
     
         8 . A combustor comprising:
 a combustor liner surrounding a combustion zone and comprising a plurality of dilution holes arranged in one or more fields of said dilution holes, each of said dilution holes extending through said combustor liner, each said dilution hole including a downstream edge in a downstream direction of a flow of a first fluid through said combustor liner;
 a support flange extending from said downstream edge into said combustion zone; and 
 a lip extending away from said support flange in the downstream direction and spaced a predetermined distance from said combustor liner. 
   
     
     
         9 . The combustor of  claim 8 , further comprising a plurality of cooling holes extending through said combustor liner, said plurality of cooling holes positioned downstream of a respective dilution hole of said dilution holes, wherein said lip extends in the downstream direction over said plurality of cooling holes. 
     
     
         10 . The combustor of  claim 9 , wherein said plurality of cooling holes comprises a plurality of non-circular cooling holes. 
     
     
         11 . The combustor of  claim 9 , wherein said plurality of cooling holes comprises a plurality of circular cooling holes. 
     
     
         12 . The combustor of  claim 9 , wherein said dilution holes are configured to channel a flow of a second fluid in a second direction substantially perpendicular to the downstream direction. 
     
     
         13 . The combustor of  claim 12 , wherein said plurality of cooling holes is configured to channel a flow of a cooling fluid in the second direction. 
     
     
         14 . The combustor of  claim 13 , wherein said lip is configured to channel the flow of the cooling fluid in the downstream direction. 
     
     
         15 . The combustor of  claim 14 , wherein said lip, said support flange, and a surface of said combustor liner define a film initiation gap configured to channel the flow of the cooling fluid in the downstream direction along said surface of said combustor liner. 
     
     
         16 . The combustor of  claim 15 , wherein the flow of the second fluid disrupts a flow of a cooling film flowing along said surface of said combustor liner, wherein said cooling fluid directed in the downstream direction along said surface of said combustor liner is configured to restart the flow of the cooling film downstream of a respective dilution hole. 
     
     
         17 . The combustor of  claim 9 , wherein said plurality of cooling holes are oriented at an oblique angle with respect to the downstream direction. 
     
     
         18 . A gas turbine engine comprising:
 a core engine comprising a high pressure compressor, a combustor, and a high pressure turbine in a serial flow arrangement, said high pressure compressor and said high pressure turbine coaxial about an axis of rotation, said combustor comprising:
 a combustor liner comprising a plurality of dilution holes, each of said dilution holes extending through said combustor liner, each of said plurality of dilution holes including a downstream edge in a direction of a flow of a first fluid through said combustor, said downstream edge of at least some of said plurality of dilution holes including a film cooling starter device comprising: 
 a support flange extending from said downstream edge into said combustor; 
 a lip extending away from said support flange in the downstream direction and spaced a predetermined distance from said combustor liner; and 
 a plurality of cooling holes extending through said combustor liner, said lip extending in the downstream direction over said plurality of cooling holes. 
   
     
     
         19 . The gas turbine engine of  claim 18 , said plurality of cooling holes are oriented approximately perpendicular to the axis of rotation. 
     
     
         20 . The gas turbine engine of  claim 18 , said plurality of cooling holes are oriented at an oblique angle with respect to the axis of rotation.