Turbine Airfoil Cooling System with Pin Fin Cooling Chambers

Abstract

A cooling system for a turbine airfoil having at least one pin fin with a dimpled outer surface is disclosed. The dimpled outer surface increases the cooling efficiency of the pin fin, which creates numerous efficiencies, including thermal efficiencies, manufacturing efficiencies and the like. The dimples may be formed from shapes including, but not limited to, circular, oval, racetrack, and hemispherical. The dimples may be aligned in a variety of configurations.

1 . A turbine airfoil, comprising:
 a generally elongated, hollow airfoil having a leading edge, a trailing edge, a tip section at a first end, a root coupled to the airfoil at an end generally opposite the first end for supporting the airfoil and for coupling the airfoil to a disc, and a cooling system formed from at least one cavity in the elongated, hollow airfoil;   an outer wall forming the generally elongated airfoil;   wherein the cooling system includes at least one pin fin having an outer surface with at least one dimple.   
     
     
         2 . The turbine airfoil of  claim 1 , wherein the at least one dimple has a generally circular shape at an intersection with the outer surface of the at least one dimple. 
     
     
         3 . The turbine airfoil of  claim 1 , wherein the at least one dimple has a generally oval shape at an intersection with the outer surface of the at least one dimple. 
     
     
         4 . The turbine airfoil of  claim 1 , wherein the at least one dimple has a generally racetrack shape with two curved ends and two generally linear sides at an intersection with the outer surface of the at least one dimple. 
     
     
         5 . The turbine airfoil of  claim 1 , wherein the at least one dimple has a generally hemispherical shape. 
     
     
         6 . The turbine airfoil of  claim 1 , wherein the outer surface of the pin fin includes a plurality of dimples. 
     
     
         7 . The turbine airfoil of  claim 6 , wherein the dimples are aligned into horizontal rows that are offset from dimples in adjacent rows. 
     
     
         8 . The turbine airfoil of  claim 1 , wherein the at least one dimple extends into the pin fin between about ½ percent to about 20 percent of the width of the pin fin. 
     
     
         9 . The turbine airfoil of  claim 1 , wherein the outer surface of the at least one pin fin includes dimples covering between about 20 percent and about 100 percent of the outer surface of the at least one pin fin. 
     
     
         10 . A turbine airfoil, comprising:
 a generally elongated, hollow airfoil having a leading edge, a trailing edge, a tip section at a first end, a root coupled to the airfoil at an end generally opposite the first end for supporting the airfoil and for coupling the airfoil to a disc, and a cooling system formed from at least one cavity in the elongated, hollow airfoil;   an outer wall forming the generally elongated airfoil;   wherein the cooling system includes a plurality of pin fins having an outer surface with a plurality of dimples.   
     
     
         11 . The turbine airfoil of  claim 10 , wherein at least one of the plurality of dimples has a generally circular shape at an intersection with the outer surface of the dimple. 
     
     
         12 . The turbine airfoil of  claim 10 , wherein at least one of the plurality of dimples has a generally oval shape at an intersection with the outer surface of the dimple. 
     
     
         13 . The turbine airfoil of  claim 10 , wherein at least one of the plurality of dimples has a generally racetrack shape with two curved ends and two generally linear sides at an intersection with the outer surface of the dimple. 
     
     
         14 . The turbine airfoil of  claim 10 , wherein at least one of the plurality of dimples has a generally hemispherical shape. 
     
     
         15 . The turbine airfoil of  claim 10 , wherein the dimples are aligned into horizontal rows that are offset from dimples in adjacent rows. 
     
     
         16 . The turbine airfoil of  claim 10 , wherein the at least one dimple extends into the pin fin between about ½ percent to about 20 percent of the width of the pin fin. 
     
     
         17 . The turbine airfoil of  claim 10 , wherein the outer surface of the at least one pin fin includes dimples covering between about 20 percent and about 100 percent of the outer surface of the at least one pin fin. 
     
     
         18 . A turbine airfoil, comprising:
 a generally elongated, hollow airfoil having a leading edge, a trailing edge, a tip section at a first end, a root coupled to the airfoil at an end generally opposite the first end for supporting the airfoil and for coupling the airfoil to a disc, and a cooling system formed from at least one cavity in the elongated, hollow airfoil;   an outer wall forming the generally elongated airfoil;   wherein the cooling system includes a plurality of generally cylindrical pin fins having an outer surface with a plurality of concave dimples that are aligned into horizontal rows that are offset from dimples in adjacent rows.   
     
     
         19 . The turbine airfoil of  claim 18 , wherein at least one of the plurality of dimples has a generally oval shape at an intersection with the outer surface of the dimple. 
     
     
         20 . The turbine airfoil of  claim 18 , wherein at least one of the plurality of dimples has a generally racetrack shape with two curved ends and two generally linear sides at an intersection with the outer surface of the dimple.