Root bow geometry for airfoil shaped vane

Abstract

A vane assembly used for controlling a turning gas flow includes multiple vanes, each of which is bowed toward a pressure side of the vane at the root of the vane.

1 . A stationary vane comprising:
 a suction side surface and a pressure side surface, each of said surfaces extending from a leading edge of the vane to a trailing edge of the vane;   a chord line extending from a midpoint of the leading edge to a midpoint of the trailing edge;   a radial line extending from a tip of the vane to an axis defined by vane assembly; and   a bowing region at a root portion of said vane operable reduce secondary flow losses, wherein the bowing region defines a junction angle between the suction side surface and an inner diameter mounting surface, wherein the angle is greater than 70 degrees.   
     
     
         2 . The stationary vane of  claim 1 , wherein said bowing region is a region of said root portion that diverges from said radial line. 
     
     
         3 . The stationary vane of  claim 2 , wherein said bowing region extends from approximately 5% span to 0% span of the vane. 
     
     
         4 . The stationary vane of  claim 2 , wherein said root portion diverges such that a 0% span of the root portion is the farthest diverged point of the root portion. 
     
     
         5 . The stationary vane of  claim 1 , wherein said vane abuts an inner diameter end wall in an installed configuration such that a junction between the vane and the end wall is approximately continuous. 
     
     
         6 . The stationary vane of  claim 1 , wherein the diverged root portion of the vane extends a full axial length of the chord line. 
     
     
         7 . The stationary vane of  claim 1 , wherein the diverged root portion of the vane extends from a throat point of said vane to a trailing edge of said vane. 
     
     
         8 . The stationary vane of  claim 1 , further comprising a vane aspect ratio of less than or equal to 1.5. 
     
     
         9 . The stationary vane of  claim 1 , wherein the stationary vane is configured for use in a duct having a duct angle of at least 10 degrees. 
     
     
         10 . A vane assembly for a gas flow duct comprising:
 an inner diameter end wall defining an axis;   an outer diameter end wall coaxial with said inner diameter end wall;   a plurality of vanes arranged circumferentially between said inner diameter end wall and said outer diameter end wall, wherein each of said vanes further comprises:
 a suction side surface and a pressure side surface, each of said surfaces extending from a leading edge of the vane to a trailing edge of the vane; 
 a chord line extending from a midpoint of the leading edge to a midpoint of the trailing edge; 
 a radial line extending from a tip of the vane to an axis defined by vane assembly; and 
 a bowing region at a root portion of said vane operable reduce secondary flow losses, wherein a junction angle between the suction side surface of the bowing region and the inner diameter endwall is greater than 70 degrees. 
   
     
     
         11 . The vane assembly of  claim 10 , wherein said bowing region is a region of said root portion that diverges from said radial line. 
     
     
         12 . The vane assembly of  claim 11 , wherein said bowing region extends from approximately 5% span to 0% span of the vane. 
     
     
         13 . The vane assembly of  claim 11 , wherein said root portion diverges such that a 0% span of the root portion is the farthest diverged point of the root portion. 
     
     
         14 . The vane assembly of  claim 10 , wherein said vane abuts an inner diameter end wall in an installed configuration such that a junction between the vane and the end wall is approximately continuous. 
     
     
         15 . The vane assembly of  claim 10 , wherein the diverged root portion of the vane extends a full axial length of the chord line. 
     
     
         16 . The stationary vane of  claim 1 , wherein the diverged root portion of the vane extends from a throat point of said vane to a trailing edge of said vane. 
     
     
         17 . The vane assembly of  claim 10 , wherein each of said plurality of vanes has a vane aspect ratio of less than or equal to 1.5. 
     
     
         18 . The vane assembly of  claim 10 , wherein said inner diameter wall and said outer diameter wall define a duct having a duct angle of greater than 10 degrees. 
     
     
         19 . The vane assembly of  claim 10 , wherein said plurality of vanes is less than or equal to 20 vanes. 
     
     
         20 . The vane assembly of  claim 19 , wherein said plurality of vanes is a number of vanes selected from the set of 12, 18 and 20 vanes.