Blade for a gas turbine

Abstract

A blade for a gas turbine includes an airfoil extending in a longitudinal direction and extending transversely to the longitudinal direction between a leading edge and a trailing edge. The airfoil has a pressure side, a suction side, and a slot-like cooling medium outlet extending along the trailing edge. The cooling medium outlet is configured to discharge cooling medium supplied from an inner space of the blade. A platform extends transversely to the longitudinal direction. An end of the airfoil merges into an underside of the platform and has a transition from the airfoil to the platform at the trailing edge of the airfoil that increases in thickness in a direction toward the underside of the platform. The cooling medium outlet extends into the platform so as to reduce an operating temperature in a region of the transition from the blade airfoil to the platform.

1 . A blade for a gas turbine, the blade comprising:
 an airfoil extending in a longitudinal direction and extending transversely to the longitudinal direction between a leading edge and a trailing edge, the airfoil having a pressure side, a suction side, and a slot-like cooling medium outlet extending along the trailing edge, the outlet configured to discharge cooling medium supplied from an inner space of the blade;   a platform extending transversely to the longitudinal direction, a first end of the airfoil merging into an underside of the platform and having a transition from the airfoil to the platform at the trailing edge of the airfoil that increases in thickness in a direction toward the underside of the platform, and   wherein the cooling medium outlet extends into the platform so as to reduce an operating temperature in a region of the transition from the blade airfoil to the platform.   
     
     
         2 . The blade as recited in  claim 1 , wherein the transition from the blade airfoil to the platform has a thickness profile having a substantially exponential shape corresponding to at least one of an inverted rampant pyramid, an inverted truncated pyramid, and an inverted virtual pyramid. 
     
     
         3 . The blade as recited in  claim 1 , wherein the transition from the blade airfoil to the platform has an approximately elliptical profile. 
     
     
         4 . The blade as recited in  claim 1 , wherein the transition from the blade airfoil to the platform extends to an edge of the platform. 
     
     
         5 . The blade as recited in  claim 2 , wherein the transition from the blade airfoil to the platform extends to an edge of the platform. 
     
     
         6 . The blade as recited in  claim 3 , wherein the transition from the blade airfoil to the platform extends to an edge of the platform. 
     
     
         7 . The blade as recited in  claim 1 , wherein the cooling medium outlet is formed between a pressure-side wall of the blade airfoil and a suction-side wall of the blade airfoil, and wherein the transition from the blade airfoil to the platform along the pressure-side wall has a curvilinear edge profile such that a wall thickness of the pressure-side wall in a region of the transition is approximately equal to a wall thickness in a remaining region of the blade airfoil. 
     
     
         8 . The blade as recited in  claim 7 , wherein the transition from the blade airfoil to the platform extends to an edge of the platform.