Cooled turbine ring segments with intermediate pressure plenums

Abstract

A ring segment for a gas turbine engine includes a panel and a cooling system. The cooling system is provided within the panel and includes an elongated intermediate plenum extending parallel to leading and trailing edges of the ring segment, and is located radially between an inner side of the panel and a hook structure extending from an outer side of the panel. A plurality of cooling fluid feed passages supply cooling fluid to the intermediate plenum, and a plurality of convective cooling passages extend through the panel from the intermediate plenum to one of the leading and trailing edges for cooling the inner side of the panel. The intermediate plenum is located in axial alignment with and defines an area of reduced thermal mass receiving impingement cooling adjacent to the hook structure.

What is claimed is: 
     
         1 . A ring segment for a gas turbine engine comprising:
 a panel comprising:
 a plurality of side edges including leading and trailing edges extending in a circumferential direction, and first and second mating edges extending in an axial direction; 
 an outer side and an inner side, wherein cooling fluid is provided to said outer side and said inner side defines at least a portion of a hot gas flow path through the gas turbine engine; and 
 a central recessed portion defining a recessed surface formed in said outer side and surrounded by a rim portion comprising an unrecessed portion extending around an outer periphery of said recessed portion along each of said side edges; 
   a front hook structure extending in a radial direction from said rim portion at a leading edge side of said recessed portion;   a rear hook structure extending in a radial direction from said rim portion at a trailing edge side of said recessed portion;   a cooling system within said panel that receives cooling fluid from said outer side of said panel for cooling said panel, said cooling system comprising:
 an elongated intermediate plenum extending in the circumferential direction and located radially between said inner side of said panel and one of said front and rear support structures; 
 a plurality of cooling fluid feed passages extending from said recessed portion to said intermediate plenum for supplying cooling fluid to said intermediate plenum; 
 a plurality of convective cooling passages extending through said panel from said intermediate plenum to one of said leading and trailing edges for cooling said inner side of said panel; and 
 said intermediate plenum being located in axial alignment with said one of said front and rear support structures and defining an area of reduced thermal mass adjacent to a radially inner end of said one of said front and rear support structures. 
   
     
     
         2 . The ring segment of  claim 1 , wherein said cooling fluid feed passages provide impingement cooling to said intermediate plenum. 
     
     
         3 . The ring segment of  claim 2 , wherein a cooling fluid pressure drop through said feed passages is less than a cooling fluid pressure drop through said convective cooling passages. 
     
     
         4 . The ring segment of  claim 3 , wherein a passage diameter of said convective cooling passages is less than a diameter of said cooling fluid feed passages, and said intermediate plenum defines a diameter greater than both said convective cooling passage diameter and said diameter of said cooling fluid feed passages. 
     
     
         5 . The ring segment of  claim 1 , wherein fluid supply ends of said convective cooling passages are located at said intermediate plenum and said fluid supply ends are axially aligned with at least a portion of said one of said front and rear support structures. 
     
     
         6 . The ring segment of  claim 1 , wherein said cooling structure further includes:
 an elongated axial plenum structure extending in the axial direction;   a plurality of cooling fluid feed passages extending from said recessed portion to said axial plenum structure for supplying cooling fluid to said axial plenum structure; and   a plurality of exit passages extending from said axial plenum structure to at least one of said first and second mating edges.   
     
     
         7 . The ring segment of  claim 6 , wherein said axial plenum structure comprises a forward plenum and a rearward plenum, and cooling fluid is supplied to said forward plenum at a different flow rate than cooling fluid supplied to said rearward plenum. 
     
     
         8 . The ring segment of  claim 6 , wherein said axial plenum structure includes first and second axial plenum structures extending in the axial direction adjacent to said first and second mating edges, respectively, and said intermediate plenum includes opposing ends located adjacent to said first and second axial plenum structures. 
     
     
         9 . The ring segment of  claim 1 , wherein said convective cooling passages extend generally parallel to said inner side of said panel and are defined by a passage diameter, and said convective cooling passages are spaced within a distance of about one passage diameter from said inner side of said panel. 
     
     
         10 . The ring segment of  claim 9 , wherein said passage diameter of said convective cooling passages is less than a diameter of said cooling fluid feed passages. 
     
     
         11 . The ring segment of  claim 1 , wherein said intermediate plenum is a first intermediate plenum located in axial alignment with said front hook structure, said cooling system further including:
 a second elongated intermediate plenum extending in the circumferential direction and located in axial alignment with said rear hook structure;   a plurality of cooling fluid feed passages extending from said recessed portion to said second intermediate plenum for supplying cooling fluid to said second intermediate plenum;   a plurality of convective cooling passages extending through said panel from said second intermediate plenum to said trailing edge for cooling said inner side of said panel.   
     
     
         12 . A ring segment for a gas turbine engine comprising:
 a panel comprising a plurality of side edges including leading and trailing edges extending in a circumferential direction, and first and second mating edges extending in an axial direction, said panel further comprising an outer side and an inner side, wherein cooling fluid is provided to said outer side and said inner side defines at least a portion of a hot gas flow path through the gas turbine engine;   front and rear support structures extending in a radial direction from said outer side of said panel;   a cooling system within said panel that receives cooling fluid from said outer side of said panel for cooling said panel, said cooling system comprising:
 first and second elongated intermediate plenums extending in the circumferential direction and located radially between said inner side of said panel and respective ones of said front and rear support structures; 
 a plurality of cooling fluid feed passages extending from said outer side of said panel to said intermediate plenums for supplying cooling fluid to said intermediate plenums; 
 a plurality of convective cooling passages extending through said panel from said first and second intermediate plenums to said leading and trailing edges, respectively, for cooling said inner side of said panel; 
 said first and second intermediate plenums being located in axial alignment with said front and rear support structures, respectively, and defining an area of reduced thermal mass adjacent to a radially inner end of each of said front and rear support structures. 
   
     
     
         13 . The ring segment of  claim 12 , wherein said convective cooling passages define a passage diameter that is less than a diameter of said cooling fluid feed passages, and said first and second intermediate plenums define a diameter greater than both said passage diameter and said diameter of said cooling fluid feed passages. 
     
     
         14 . The ring segment of  claim 12 , wherein fluid supply ends of said convective cooling passages are located at said first and second intermediate plenums, and said fluid supply ends are axially aligned with at least a portion of respective ones of said front and rear support structures. 
     
     
         15 . The ring segment of  claim 12 , wherein said cooling structure further includes:
 first and second elongated axial plenum structures extending in the axial direction adjacent to said first and second mating edges, respectively;   a plurality of cooling fluid feed passages extending from said outer side of said panel to said axial plenum structures for supplying cooling fluid to said axial plenum structures; and   a plurality of exit passages extending from said axial plenum structures to one of said first and second mating edges.   
     
     
         16 . The ring segment of  claim 15 , wherein each of said first and second axial plenum structures comprises a forward plenum and a rearward plenum, and cooling fluid is supplied to said forward plenums at a different flow rate than cooling fluid supplied to said rearward plenums. 
     
     
         17 . The ring segment of  claim 15 , including a fluid connection between ends of each of said first and second intermediate plenums and said first and second axial plenum structures. 
     
     
         18 . A ring segment for a gas turbine engine comprising:
 a panel comprising a plurality of side edges including leading and trailing edges extending in a circumferential direction, and first and second mating edges extending in an axial direction, said panel further comprising an outer side and an inner side, wherein cooling fluid is provided to said outer side and said inner side defines at least a portion of a hot gas flow path through the gas turbine engine;   a cooling system within said panel that receives cooling fluid from said outer side of said panel for cooling said panel, said cooling system comprising:
 an elongated intermediate plenum extending in the circumferential direction and located radially between said inner and outer sides of said panel; 
 a plurality of cooling fluid feed passages extending from said outer side of said panel to said intermediate plenum for supplying cooling fluid to said intermediate plenums; 
 a plurality of convective cooling passages extending through said panel from said intermediate plenum to one of said leading and trailing edges for cooling said inner side of said panel; and 
 said convective cooling passages extend axially generally parallel to said inner side of said panel and are defined by a passage diameter, and said convective cooling passages are spaced within a distance of about one passage diameter from said inner side of said panel. 
   
     
     
         19 . The ring segment of  claim 18 , wherein said intermediate plenum is aligned in the axial direction with a radially inner end of a hook structure that extends in a radial direction outwardly from said outer side of said panel for supporting said panel within the engine, said intermediate plenum effecting an area of reduced thermal mass adjacent to said inner end of said hook structure. 
     
     
         20 . The ring segment of  claim 18 , wherein said passage diameter of said convective cooling passages is less than a diameter of said cooling fluid feed passages, and said intermediate plenum defines a diameter greater than both said convective cooling passage diameter and said diameter of said cooling fluid feed passages.