Turbine blade with improved trailing edge cooling

Abstract

A turbine blade ( 110 ) is provided, where an exterior surface of the turbine blade ( 110 ) is exposed to a hot combustion gas ( 125 ) above a flow path line ( 141 ). The turbine blade ( 110 ) includes a trailing edge pin bank cooling channel ( 118 ) in an airfoil section ( 112 ), a cooling air supply channel ( 120 ) in a root section ( 114 ), and a channel ( 122 ) shaped with a radius of curvature ( 126 ), to extend the channel ( 122 ) across the flow path line ( 141 ) and interconnect the cooling air supply channel ( 120 ) to the trailing edge pin bank cooling channel ( 118 ). A width of the trailing edge pin bank cooling channel ( 118 ) is adjusted, such that the width at an inner diameter region ( 128 ) and an outer diameter region ( 131 ) is less than the width at an intermediate region ( 130 ) between the inner and outer diameter regions ( 128,131 ).

1 . A turbine blade including a trailing edge cooling channel wherein the improvement comprises the trailing edge cooling channel having a maximum width proximate a mid-span region of an airfoil section of the blade and extending via a radius of curvature to below a flow path line of the blade. 
     
     
         2 . A turbine blade including an airfoil section, a root section, and a platform section between the airfoil section and the root section, wherein an exterior surface of said turbine blade is exposed to a hot combustion gas above a flow path line, said turbine blade comprising:
 a trailing edge pin bank cooling channel in the airfoil section;   a cooling air supply channel in the root section;   a channel interconnecting the cooling air supply channel to the trailing edge pin bank cooling channel, said channel having a radius of curvature to extend the channel from the cooling air supply channel in the root section, across the flow path line and to the trailing edge pin bank cooling channel in the airfoil section.   
     
     
         3 . The turbine blade of  claim 2 , wherein said airfoil section extends in a radial direction from an inner diameter region attached to the platform section, to an outer diameter region; and wherein a width of the trailing edge pin bank cooling channel at the inner diameter region and at the outer diameter region is less than a width of the trailing edge pin bank cooling channel at an intermediate region positioned between the inner diameter region and the outer diameter region. 
     
     
         4 . The turbine blade of  claim 3 , wherein said width of the trailing edge pin bank cooling channel is a maximum width at the intermediate region positioned half-way between the inner diameter region and the outer diameter region. 
     
     
         5 . The turbine blade of  claim 2 , further comprising a rib being radially positioned to cooperate with the radius of curvature of the channel to define a predetermined cross-sectional flow area through the channel at an entrance of the trailing edge pin bank cooling channel. 
     
     
         6 . A ceramic core used to cast the turbine blade of  claim 2  and including a portion defining the channel. 
     
     
         7 . A turbine blade including an airfoil section, a root section and a platform section between the airfoil section and the root section, said turbine blade comprising:
 a trailing edge pin bank cooling channel in the airfoil section;   wherein said airfoil section extends in a radial direction from an inner diameter region attached to the platform section, to an outer diameter region;   and wherein a width of the trailing edge pin bank cooling channel at the inner diameter region and at the outer diameter region is less than the width of the trailing edge pin bank cooling channel at an intermediate region positioned between the inner diameter region and the outer diameter region.   
     
     
         8 . The turbine blade of  claim 7 , wherein an exterior surface of said turbine blade is exposed to a hot combustion gas above a flow path line, said turbine blade further comprising:
 a cooling air supply channel in the root section; and   a channel to interconnect the cooling air supply channel to the trailing edge pin bank cooling channel, said channel having a radius of curvature to extend the channel from the cooling air supply channel in the root section across the flow path line and to the trailing edge pin bank cooling channel in the airfoil section.   
     
     
         9 . The turbine blade of  claim 7 , wherein said width of the trailing edge pin bank cooling channel is a maximum width at the intermediate region positioned half-way between the inner diameter region and the outer diameter region. 
     
     
         10 . The turbine blade of  claim 8 , further comprising a rib being radially positioned to cooperate with the radius of curvature of the channel to define a predetermined cross-sectional flow area through the channel at an entrance of the trailing edge pin bank cooling channel. 
     
     
         11 . A ceramic core used to cast the turbine blade of  claim 7 .