Gas turbine with annular heat shield

Abstract

A gas turbine includes a supporting structure which concentrically surrounds a hot gas path and is shielded with respect to the hot gas path by an annular heat shield ( 15 ′), which heat shield ( 15 ′) includes a multiplicity of segments which are arranged one behind the other in a circumferential direction and which in each case butt against one another in the circumferential direction so as to form a gap, seals ( 16 ′), being arranged for sealing off the gaps between the segments butting against one another, the seals having thin elongate sealing strips ( 23 ), which are accommodated in corresponding sealing slots ( 19 ), delimited transversely with respect to the longitudinal direction by a wall ( 25 ), in the mutually opposite end faces of the segments of the heat shield ( 15 ′) which butt against one another. Vibrationally-induced rubbing through of the wall is inhibited or prevented by the frictional surface between the wall ( 25 ) and the sealing strips ( 23 ) being markedly enlarged with respect to the end face ( 22 ) of the sealing strip ( 23 ).

1 . A gas turbine comprising:
 a supporting structure which concentrically surrounds a hot gas path;   an annular heat shield configured and arranged to shield the supporting structure from the hot gas path, the heat shield comprising a plurality of segments circumferentially arranged one behind the other and circumferentially abutting against one another to form gaps, each pair of abutting segments including opposing faces;   sealing slots in each of the plurality of segments, the slots transversely delimited with respect to the longitudinal direction by a wall portion of each segment, the sealing slots positioned in said opposing faces of abutting segments;   seals configured and arranged to seal off the gaps between the segments, said seals comprising thin elongate sealing strips positioned in said sealing slots; and   an enlarged frictional surface between said wall portion and said sealing strip configured and arranged to reduce friction between said wall and said sealing strip, and to inhibit the frictionally-induced piercing of the wall by the sealing strip.   
   
   
       2 . The gas turbine as claimed in  claim 1 , wherein the sealing strips have, at an end facing the wall, an angled end portion the outside of which end portion forms a contact surface with the wall. 
   
   
       3 . The gas turbine as claimed in  claim 2 , further comprising:
 angled slot extensions at the ends of the sealing slots into which the sealing strips engage with their angled end portions.   
   
   
       4 . The gas turbine as claimed in  claim 3 , wherein the slot extensions are angled at right angles. 
   
   
       5 . The gas turbine as claimed in  claim 3 , wherein the slot extensions are angled at an angle of 90°±δ, 0<δ≦20°. 
   
   
       6 . The gas turbine as claimed in  claim 3 , wherein the slot extensions comprise slot portions intersecting the sealing slots.