Internal cooling system with corrugated insert forming nearwall cooling channels for airfoil usable in a gas turbine engine

Abstract

An airfoil for a gas turbine engine in which the airfoil includes an internal cooling system formed from one or more midchord cooling channels with a corrugated insert positioned therein and creating nearwall leading edge, pressure side and suction side nearwall cooling channels. The corrugated insert may be formed from a wall that oscillates in a repeating pattern between peaks and valleys, such that the peaks are closer to an inner surface of the outer wall forming the generally elongated hollow airfoil The corrugated insert may work in concert with the rows of partition walls to create periodic impingement on the inner surface of the outer wall Such cooling system provides adequate cooling for use in environments in which few, if any, cooling holes are desired, such as in crude oil engine applications

We claim: 
     
         1 . A turbine airfoil, comprising:
 a generally elongated hollow airfoil formed from an outer wall, and having a leading edge, a trailing edge, a pressure side, a suction side, and a cooling system positioned within interior aspects of the generally elongated hollow airfoil;   at least one midchord cooling channel with at least one corrugated insert positioned therein and creating a leading edge nearwall cooling channel between the leading edge and the corrugated insert, a suction side nearwall cooling channel between the suction side and the corrugated insert and a pressure side nearwall cooling channel between the pressure side and the corrugated insert;   wherein the corrugated insert is formed from a wall that oscillates in a repeating pattern between peaks and valleys, such that the peaks are closer to an inner surface of the outer wall forming the generally elongated hollow airfoil;   a plurality of rows of partition walls extending from the inner surface forming the outer wall and into the midchord cooling channel, wherein the partition walls include gaps therein and wherein the rows of partition walls are generally aligned with a direction of cooling fluid flow from the leading edge chordwise toward the trailing edge; and   wherein at least a portion of the peaks in the corrugated insert extending radially outward are aligned with the gaps within at least a portion of at least one partition wall   
     
     
         2 . The turbine airfoil of  claim 1 , wherein at least one partition wall includes gaps therein that extend an entire length of the at least one partition wall 
     
     
         3 . The turbine airfoil of  claim 1 , wherein at least one partition wall is linear. 
     
     
         4 . The turbine airfoil of  claim 1 , wherein each of the partition walls is linear and each of the partition walls are parallel with each other. 
     
     
         5 . The turbine airfoil of  claim 1 , wherein at least one partition wall is formed from a first and second subpartition walls, wherein the second subpartition wall is offset laterally from first subpartition wall and wherein the first and second subpartition walls are staggered in an alternating manner moving in a direction from the leading edge toward the trailing edge. 
     
     
         6 . The turbine airfoil of  claim 1 , wherein each partition wall is formed from a first and second subpartition walls, wherein the second subpartition wall is offset laterally from first subpartition wall and wherein the first and second subpartition walls are staggered in an alternating manner moving in a direction from the leading edge toward the trailing edge. 
     
     
         7 . The turbine airfoil of  claim 6 , wherein a second subpartition wall is positioned along an axis that is equidistant from a first subpartition wall within a same partition wall as the second subpartition wall and a first subpartition wall within an adjacent partition wall. 
     
     
         8 . The turbine airfoil of  claim 1 , further comprising a plurality of miniribs extend from the inner surface forming the outer wall and extending between adjacent partition walls, wherein the miniribs are nonparallel with the partition walls and are shorter in height extending from the inner surface than adjacent partition walls 
     
     
         9 . The turbine airfoil of  claim 8 , wherein the plurality of miniribs are aligned with each other and are orthogonal to the adjacent partition walls 
     
     
         10 . The turbine airfoil of  claim 1 , further comprising at least one trailing edge cooling channel positioned between the at least one midchord cooling channel and the trailing edge of the generally elongated hollow airfoil, wherein the at least one trailing edge cooling channel includes a plurality of pin fins extending from the outer wall forming the pressure side to the suction side and forming zigzag cooling flow channels within the at least one trailing edge cooling channel 
     
     
         11 . The turbine airfoil of  claim 10 , wherein at least a portion of the pin fins have cross-sectional areas with a leading edge, a trailing edge that is positioned on a downstream corner and separated from the leading edge by a concave side surface and a convex side surface 
     
     
         12 . The turbine airfoil of  claim 11 , wherein at least one of the zigzag cooling flow channels is formed from a plurality of pin fins aligned such that the concave and convex side surfaces alternate moving towards the trailing edge. 
     
     
         13 . The turbine airfoil of  claim 11 , wherein a first upstream pin fin has a cross-sectional area formed from an upstream section and a downstream section, wherein the upstream section is generally linear with a constant width, and the downstream section is generally linear with a tapered width that reduces in width moving towards the trailing edge, wherein the upstream and downstream sections are nonlinear and nonorthogonal with each other 
     
     
         14 . A turbine airfoil, comprising:
 a generally elongated hollow airfoil formed from an outer wall, and having a leading edge, a trailing edge, a pressure side, a suction side, and a cooling system positioned within interior aspects of the generally elongated hollow airfoil;   at least one midchord cooling channel with at least one corrugated insert positioned therein and creating a leading edge nearwall cooling channel between the leading edge and the corrugated insert, a suction side nearwall cooling channel between the suction side and the corrugated insert and a pressure side nearwall cooling channel between the pressure side and the corrugated insert;   wherein the corrugated insert is formed from a wall that oscillates in a repeating pattern between peaks and valleys, such that the peaks are closer to an inner surface of the outer wall forming the generally elongated hollow airfoil;   a plurality of rows of partition walls extending from the inner surface forming the outer wall and into the midchord cooling channel, wherein the partition walls include gaps therein and wherein the rows of partition walls are generally aligned with a direction of cooling fluid flow from the leading edge chordwise toward the trailing edge;   wherein at least a portion of the peaks in the corrugated insert extending radially outward are aligned with the gaps within at least a portion of at least one partition wall;   a plurality of miniribs extending from the inner surface forming the outer wall and extending between adjacent partition walls, wherein the miniribs are nonparallel with the partition walls and are shorter in height extending from the inner surface than adjacent partition walls;   at least one trailing edge cooling channel positioned between the at least one midchord cooling channel and the trailing edge of the generally elongated hollow airfoil, wherein the at least one trailing edge cooling channel includes a plurality of pin fins extending from the outer wall forming the pressure side to the suction side and forming zigzag cooling flow channels within the at least one trailing edge cooling channel; and   wherein at least a portion of the pin fins have cross-sectional areas with a leading edge, a trailing edge that is positioned on a downstream corner and separated from the leading edge by a concave side surface and a convex side surface   
     
     
         15 . The turbine airfoil of  claim 14 , wherein each of the partition walls is linear and each of the partition walls is parallel with each other. 
     
     
         16 . The turbine airfoil of  claim 14 , wherein each partition wall is formed from a first and second subpartition walls, wherein the second subpartition wall is offset laterally from first subpartition wall and wherein the first and second subpartition walls are staggered in an alternating manner moving in a direction from the leading edge toward the trailing edge. 
     
     
         17 . The turbine airfoil of  claim 16 , wherein a second subpartition wall is positioned along an axis that is equidistant from a first subpartition wall within a same partition wall as the second subpartition wall and a first subpartition wall within an adjacent partition wall 
     
     
         18 . The turbine airfoil of  claim 14 , wherein the miniribs are aligned with each other and are orthogonal to the adjacent partition walls. 
     
     
         19 . The turbine airfoil of  claim 14 , wherein a first upstream pin fin has a cross-sectional area formed from an upstream section and a downstream section, wherein the upstream section is generally linear with a constant width, and the downstream section is generally linear with a tapered width that reduces in width moving towards the trailing edge, wherein the upstream and downstream sections are nonlinear and nonorthogonal with each other and wherein at least one of the zigzag cooling flow channels is formed from a plurality of pin fins aligned such that the concave and convex side surfaces alternate moving towards the trailing edge. 
     
     
         20 . A turbine airfoil, comprising:
 a generally elongated hollow airfoil formed from an outer wall, and having a leading edge, a trailing edge, a pressure side, a suction side, and a cooling system positioned within interior aspects of the generally elongated hollow airfoil;   at least one midchord cooling channel with at least one corrugated insert positioned therein and creating a leading edge nearwall cooling channel between the leading edge and the corrugated insert, a suction side nearwall cooling channel between the suction side and the corrugated insert and a pressure side nearwall cooling channel between the pressure side and the corrugated insert;   wherein the corrugated insert is formed from a wall that oscillates in a repeating pattern between peaks and valleys, such that the peaks are closer to an inner surface of the outer wall forming the generally elongated hollow airfoil;   a plurality of rows of partition walls extending from the inner surface forming the outer wall and into the midchord cooling channel, wherein the partition walls include gaps therein and wherein the rows of partition walls are generally aligned with a direction of cooling fluid flow from the leading edge chordwise toward the trailing edge;   wherein at least a portion of the peaks in the corrugated insert extending radially outward are aligned with the gaps within at least a portion of at least one partition wall;   wherein each partition wall is formed from a first and second subpartition walls, wherein the second subpartition wall is offset laterally from first subpartition wall and wherein the first and second subpartition walls are staggered in an alternating manner moving in a direction from the leading edge toward the trailing edge;   a plurality of miniribs extending from the inner surface forming the outer wall and extending between adjacent partition walls, wherein the miniribs are nonparallel with the partition walls and are shorter in height extending from the inner surface than adjacent partition walls;   at least one trailing edge cooling channel positioned between the at least one midchord cooling channel and the trailing edge of the generally elongated hollow airfoil, wherein the at least one trailing edge cooling channel includes a plurality of pin fins extending from the outer wall forming the pressure side to the suction side and forming zigzag cooling flow channels within the at least one trailing edge cooling channel;   wherein at least a portion of the pin fins have cross-sectional areas with a leading edge, a trailing edge that is positioned on a downstream corner and separated from the leading edge by a concave side surface and a convex side surface; and   wherein the upstream and downstream sections are nonlinear and nonorthogonal with each other and wherein at least one of the zigzag cooling flow channels is formed from a plurality of pin fins aligned such that the concave and convex side surfaces alternate moving towards the trailing edge.