Turbine blade and method for cooling the turbine blade

Abstract

A turbine blade includes an outer surface, and a rim surrounds at least a portion of the outer surface. A trench in the rim extends around at least a portion of the outer surface.

What is claimed is: 
     
         1 . A turbine blade, comprising:
 a. an outer surface;   b. a rim that surrounds at least a portion of the outer surface; and   c. a trench in the rim, wherein the trench extends around at least a portion of the outer surface.   
     
     
         2 . The turbine blade as in  claim 1 , wherein the trench extends continuously in the rim around the entire outer surface. 
     
     
         3 . The turbine blade as in  claim 1 , wherein the rim includes an outer wall that defines an outer portion of the trench and an inner wall that defines an inner portion of the trench, and the outer wall is higher than the inner wall. 
     
     
         4 . The turbine blade as in  claim 1 , wherein the rim includes an outer wall that defines an outer portion of the trench and an inner wall that defines an inner portion of the trench, and the inner wall includes one or more notches that provide fluid communication from the trench to the outer surface. 
     
     
         5 . The turbine blade as in  claim 1 , further comprising a plurality of cooling passages in the trench that provide fluid communication from inside the turbine blade. 
     
     
         6 . The turbine blade as in  claim 5 , wherein the plurality of cooling passages in the trench are angled toward a trailing edge of the turbine blade. 
     
     
         7 . A turbine blade, comprising:
 a. an outer surface;   b. a pressure side wall that extends from a leading edge to a trailing edge along a first portion of the outer surface;   c. a suction side wall opposed to the pressure side wall, wherein the suction side wall extends from the leading edge to the trailing edge along a second portion of the outer surface; and   d. a groove in at least one of the pressure side wall or the suction side wall, wherein the groove extends around at least a portion of the outer surface.   
     
     
         8 . The turbine blade as in  claim 7 , wherein the groove extends continuously in the pressure side wall and the suction side wall around the entire outer surface. 
     
     
         9 . The turbine blade as in  claim 7 , wherein the pressure side wall includes an outer wall that defines an outer portion of the groove and an inner wall that defines an inner portion of the groove, and the outer wall is higher than the inner wall. 
     
     
         10 . The turbine blade as in  claim 7 , wherein the pressure side wall includes an outer wall that defines an outer portion of the groove and an inner wall that defines an inner portion of the groove, and the inner wall includes one or more notches that provide fluid communication from the groove to the outer surface. 
     
     
         11 . The turbine blade as in  claim 7 , further comprising a plurality of cooling passages in the groove that provide fluid communication from inside the turbine blade. 
     
     
         12 . The turbine blade as in  claim 11 , wherein the plurality of cooling passages in the trench are angled toward a trailing edge of the turbine blade. 
     
     
         13 . A turbine blade, comprising:
 a. an outer surface;   b. a first wall that surrounds at least a portion of the outer surface; and   c. a second wall that surrounds at least a portion of the first wall to define a trench between the first and second walls, wherein the trench extends around at least a portion of the outer surface.   
     
     
         14 . The turbine blade as in  claim 13 , wherein the trench extends continuously around the entire outer surface. 
     
     
         15 . The turbine blade as in  claim 13 , wherein the first wall is shorter than the second wall. 
     
     
         16 . The turbine blade as in  claim 13 , wherein the first wall includes one or more notches that provide fluid communication from the trench to the outer surface. 
     
     
         17 . The turbine blade as in  claim 13 , further comprising a plurality of cooling passages in the trench that provide fluid communication from inside the turbine blade. 
     
     
         18 . The turbine blade as in  claim 17 , wherein the plurality of cooling passages in the trench are angled toward a trailing edge of the turbine blade.