Sealing element for a gas turbine, a gas turbine including said sealing element and method for cooling said sealing element

Abstract

A sealing element for a gas turbine, which is provided with at least one rotor ring and at least a plurality of rotor blades radially arranged about the rotor ring and having an end portion fixed to the rotor ring, is provided with a wall, which is adapted to be coupled to the rotor ring and to at least one rotor blade, has an external face adapted to be arranged in contact with a hot working fluid in the gas turbine and an internal face adapted to be arranged in contact with a cooling fluid of the gas turbine, and a gap, which is adapted to be travelled through by the cooling fluid.

1 . A sealing element ( 22 ) for a gas turbine ( 1 ); the gas turbine ( 1 ) including at least one rotor ring ( 2 ) and at least a plurality of rotor blades ( 3 ) radially arranged about the rotor ring ( 2 ) and having an end portion ( 7 ) fixed to the rotor ring ( 2 ); the sealing element ( 22 ) including a wall ( 23 ), which is adapted to be coupled to the rotor ring ( 2 ) and to at least one rotor blade ( 3 ) and is provided with an external face ( 24 ) adapted to be arranged in contact with a hot working fluid in the gas turbine ( 1 ) and with an internal face ( 25 ) adapted to be arranged in contact with a cooling fluid of the gas turbine ( 1 );
 the sealing element ( 22 ) being characterized in that the wall ( 23 ) has a gap ( 29 ), which is adapted to be travelled through by the cooling fluid.   
   
   
       2 . An element according to  claim 1 , characterized in that the wall ( 23 ) has an upper edge ( 26 ) adapted to engage a corresponding circumferential groove ( 20 ) of a rotor blade ( 3 ); the gap ( 29 ) substantially extending close to the upper edge ( 26 ). 
   
   
       3 . An element according to  claim 1 , characterized in that the wall ( 23 ) has a lower edge ( 27 ) adapted to engage a circumferential seat ( 28 ) made in the rotor ring ( 2 ). 
   
   
       4 . An element according to  claim 2 , characterized in that the internal face ( 25 ) of the wall ( 23 ) is provided with at least one inlet ( 31 ) for feeding the gap ( 29 ) with the cooling fluid of the gas turbine ( 1 ). 
   
   
       5 . An element according to  claim 4 , characterized in that the inlet ( 31 ) is arranged on the internal face ( 25 ), essentially close to the upper edge ( 26 ). 
   
   
       6 . An element according to  claim 4 , characterized in that the external face ( 24 ) of the wall ( 23 ) is provided with at least one outlet ( 30 ) for communicating the gap ( 29 ) with the hot working fluid of the gas turbine ( 1 ). 
   
   
       7 . An element according to  claim 6 , characterized in that the outlet ( 30 ) is arranged on the external face ( 24 ), essentially close to the upper edge ( 26 ). 
   
   
       8 . An element according to  claim 6 , characterized in that the inlet ( 31 ) and the outlet ( 30 ) are circumferentially offset. 
   
   
       9 . An element according to  claim 2 , characterized in that the gap ( 29 ) is open at the upper edge ( 26 ) of the wall ( 23 ). 
   
   
       10 . An element according to  claim 3 , characterized in that the gap ( 29 ) deeply extends into the wall ( 23 ) for a length equal to about 1/25 of the entire length of the wall ( 23 ) between the upper edge ( 26 ) and the lower edge ( 27 ). 
   
   
       11 . An element according to  claim 3 , characterized in that it includes a plurality of ribs ( 33 ), which extend from the internal face ( 25 ) of the wall ( 23 ). 
   
   
       12 . An element according to  claim 11 , characterized in that the ribs ( 33 ) are parallel to each other and essentially orthogonal to the upper edge ( 26 ) of the wall ( 23 ); the ribs ( 33 ) essentially extending for the entire length of the wall ( 23 ) between the upper edge ( 26 ) and the lower edge ( 27 ). 
   
   
       13 . An element according to  claim 2 , characterized in that it includes a blocking element ( 34 ) integrally connected to the wall ( 23 ) of the sealing element ( 22 ) and having a tip-shaped end ( 36 ), adapted to be arranged in a corresponding seat ( 37 ) defined by two adjacent rotor blades ( 3 ). 
   
   
       14 . An element according to  claim 2 , characterized in that the gap ( 29 ) is provided with a plurality of fins ( 39 ) which extend from two corresponding internal faces ( 40 ) of the gap ( 29 ). 
   
   
       15 . An element according to  claim 14 , characterized in that the fins ( 39 ) are transversally arranged with respect to the corresponding faces ( 40 ). 
   
   
       16 . A gas turbine including at least one rotor ring ( 2 ) and at least a plurality of rotor blades ( 3 ) radially arranged about the rotor ring ( 2 ) and having an end portion ( 7 ) fixed to the rotor ring ( 2 ); the gas turbine ( 1 ) being characterized in that it includes at least one sealing element ( 22 ) according to  claim 1 . 
   
   
       17 . A method for cooling a sealing element ( 22 ) for a gas turbine ( 1 ); the gas turbine ( 1 ) including at least one rotor ring ( 2 ) and at least a plurality of rotor blades ( 3 ) radially arranged about the rotor ring ( 2 ) and having an end portion ( 7 ) fixed to the rotor ring ( 2 ); the sealing element ( 22 ) including a wall ( 23 ), which is adapted to be coupled to the rotor ring ( 2 ) and to at least one rotor blade ( 3 ) and is provided with an external face ( 24 ) adapted to be arranged in contact with a hot working fluid in the gas turbine ( 1 ) and with an internal face ( 25 ) adapted to be arranged in contact with a cooling fluid of the gas turbine ( 1 ); the method being characterized in that it includes the step of conveying the cooling fluid into a gap ( 29 ) of the wall ( 23 ) of the sealing element ( 22 ).