Film cooling of turbine components

Abstract

A turbine component includes a flow path surface and a trench disposed in the flow path surface. At least one cooling through hole is located in the trench and is capable of injecting a cooling flow onto the flow path surface of the turbine component. The cooling flow forms a cooling film on the flow path surface. A method of cooling a turbine component includes injecting a cooling flow onto a flow path surface of the turbine component through at least one cooling through hole disposed in a trench in the turbine component. A cooling film is formed by the cooling flow between the flow path surface and a hot gas flow.

1 . A turbine component comprising:
 a flow path surface;   a trench disposed in the flow path surface; and   at least one cooling through hole disposed in the trench, the at least one cooling through hole fluidly coupled with the flow path surface of the turbine component, and capable of producing a cooling film on the flow path surface.   
   
   
       2 . The turbine component of  claim 1  including at least one flow diverter disposed downstream of the at least one cooling through hole for spreading the cooling film over the flow path surface. 
   
   
       3 . The turbine component of  claim 2  wherein the at least one flow diverter comprises two diverter sidewalls extending from a downstream wall at a sidewall angle. 
   
   
       4 . The turbine component of  claim 3  wherein each diverter sidewall extends toward an adjacent diverter sidewall of an adjacent flow diverter. 
   
   
       5 . The turbine component of  claim 4  wherein each flow diverter is disposed at substantially a same lateral position as a corresponding cooling through hole. 
   
   
       6 . The turbine component of  claim 3  wherein each diverter sidewall extends toward an adjacent diverter sidewall of the same flow diverter. 
   
   
       7 . The turbine component of  claim 2  wherein the two diverter sidewalls extend downstream diverging from a vertex at a sidewall angle. 
   
   
       8 . The turbine component of  claim 7  wherein at least a portion of the at least one flow diverter is disposed in a corresponding cooling through hole. 
   
   
       9 . The turbine component of  claim 1  wherein the trench comprises an upstream trench wall disposed upstream of the at least one cooling through hole and a downstream trench surface disposed downstream of the at least one cooling through hole. 
   
   
       10 . The turbine component of  claim 9  wherein the upstream trench wall extends substantially radially outwardly from a trench base. 
   
   
       11 . The turbine component of  claim 9  wherein the downstream trench surface slopes radially outwardly from a trench base. 
   
   
       12 . The turbine component of  claim 1  wherein the at least one cooling through hole has an elliptically shaped exit. 
   
   
       13 . The turbine component of  claim 12  wherein the at least one cooling through hole includes a diffusion surface sloping radially inwardly from a downstream exit portion of the at least one cooling through hole. 
   
   
       14 . The turbine component of  claim 1  comprising a substrate layer and a coating layer. 
   
   
       15 . The turbine component of  claim 14  wherein the at least one cooling through hole is disposed in the substrate layer, 
   
   
       16 . The turbine component of  claim 14  wherein at least one flow diverter is disposed in the coating layer for spreading the cooling film over the flow path surface. 
   
   
       17 . A method of cooling a turbine component comprising:
 injecting a cooling flow onto a flow path surface of the turbine component through at least one cooling through hole disposed in a trench in the turbine component; and   forming a cooling film between the flow path surface and a hot gas flow.   
   
   
       18 . The method of  claim 17  comprising:
 flowing the cooling film into contact with at least one flow diverter disposed downstream of the at least one cooling through hole; and   spreading the cooling film over the flow path surface via the at least one flow diverter.   
   
   
       19 . The method of  claim 18  comprising splitting the cooling flow via the at least one flow diverter wherein the at least one flow diverter is disposed at least partially within a corresponding cooling through hole. 
   
   
       20 . The method of  claim 17  wherein injecting a cooling flow includes urging at least a portion of the cooling flow across a diffusion surface of the at least one cooling through hole, the diffusion surface sloping radially inwardly from a downstream exit portion of the at least one cooling through hole.