Turbine airfoil-sidewall integration

Abstract

An arrangement for turbine bucket or nozzle airfoils that accounts for the radial variation of inlet flow angle with the boundary layer of flow adjacent to the inner and outer sidewalls. Local chambering of the airfoil sections in the region of the sidewalls provides an airfoil and fillet with an optimum shape for accommodating the radial distribution of the inlet flow angle for the working fluid in the sidewall region.

1 . A turbine stage comprising:
 a row of airfoils integrally joined to corresponding sidewalls and spaced laterally apart to define respective flow passages therebetween for channeling a working fluid; each of said airfoils including a concave pressure side and a laterally opposite convex suction side, and extending in chord between opposite leading and trailing edges; each of said airfoils blending with said sidewalls in an arcuate fillet, a region of said airfoils in proximity to the corresponding sidewall and the associated arcuate fillet forming a surface adapted to optimize a radial variation in inlet flow angle of the working fluid in proximity to the region.   
     
     
         2 . The turbine stage according to  claim 1 , wherein said region of said airfoils in proximity to the corresponding sidewall comprises a radial location of about 5% airfoil length from the corresponding sidewall. 
     
     
         3 . The turbine stage according to  claim 1 , wherein said region of said airfoils in proximity to the corresponding sidewall comprises a radial location of about 10% airfoil length from the corresponding sidewall. 
     
     
         4 . The turbine stage according to  claim 3 , wherein said blending includes the leading edge of the airfoil on at least one of the suction side and on the pressure side. 
     
     
         5 . The turbine stage according to  claim 4  wherein said blending is provided from the leading edge of the airfoil to about 50% chord length on at least one of the suction side and on the pressure side of the airfoil. 
     
     
         6 . The turbine stage according to  claim 4 , wherein said turbine stage comprises fixed nozzles. 
     
     
         7 . The turbine stage according to  claim 4 , wherein said turbine stage comprises rotating blades. 
     
     
         8 . The turbine stage according to  claim 4 , wherein said turbine stage comprises a stage of a gas turbine. 
     
     
         9 . The turbine stage according to  claim 4  wherein said turbine stage comprises a stage of a steam turbine. 
     
     
         10 . The turbine stage according to  claim 4 , wherein said turbine stage comprises a stage of a compressor. 
     
     
         11 . A turbine comprising:
 a turbine casing;   a rotor;   a stator; and   a row of airfoils integrally joined to corresponding sidewalls and spaced laterally apart to define respective flow passages therebetween for channeling a working fluid; each of said airfoils including a concave pressure side and a laterally opposite convex suction side, and extending in chord between opposite leading and trailing edges; each of said airfoils blending with said sidewalls in an arcuate fillet, a region of said airfoils in proximity to the corresponding sidewall and the associated arcuate fillet forming a surface adapted to optimize a radial variation in inlet flow angle of the working fluid in proximity to the region.   
     
     
         12 . A turbine stage according to  claim 11 , wherein said region of said airfoils in proximity to the corresponding sidewall comprises a radial location of about 5% airfoil length from the corresponding sidewall. 
     
     
         13 . A turbine stage according to  claim 11 , wherein said region of said airfoils in proximity to the corresponding sidewall comprises a radial location of about 10% airfoil length from the corresponding sidewall. 
     
     
         14 . A turbine stage according to  claim 12  wherein said blending includes the leading edge of the airfoil on at least one of the suction side and on the pressure side. 
     
     
         15 . A turbine stage according to  claim 12  wherein said blending is provided from the leading edge of the airfoil to about 50% chord length on at least one of the suction side and on the pressure side of the airfoil. 
     
     
         16 . A turbine stage according to  claim 12  wherein said turbine airfoils comprise fixed nozzles. 
     
     
         17 . A turbine stage according to  claim 12  wherein said turbine airfoils comprise rotating blades. 
     
     
         18 . A turbine stage according to  claim 12  wherein said turbine comprises a gas turbine. 
     
     
         19 . A turbine stage according to  claim 12  wherein said turbine comprises a steam turbine. 
     
     
         20 . A turbine stage according to  claim 12  wherein said turbine stage comprises a stage of a compressor.