Fluid Flow Machine

Abstract

A fluid flow machine has a stator, a rotor which is supported so as to be rotatable relative to the stator, and a brush seal which seals a gap formed between the stator and rotor in a radial direction to prevent the passage of fluid. The brush seal has a brush holder and a plurality of sealing bristles, each of which has a first end that is fastened to the brush holder and a second end that contacts a sealing surface. The sealing surface is rotationally displaceable relative to the second ends of the respective sealing bristles. The sealing surface is formed by a circumferential surface of an intermediate sleeve which is arranged between the stator and rotor and which radially divides the gap.

1 . A fluid flow machine comprising
 a stator ( 10 ),   a rotor ( 20 ) supported so as to be rotatable relative to the stator ( 10 ), said stator and rotor defining a gap (S) therebetween in a radial direction (RR);   a brush seal ( 50 ′) for sealing said gap (S) between said stator and said rotor to prevent a leakage of fluid, said the brush seal comprising a brush holder ( 51 ) and a plurality of sealing bristles ( 52 );   a sealing surface (D′) in contact with said sealing bristles; each sealing bristle having a first end fastened to said brush holder ( 51 ) and a second end contacting said sealing surface (D′);   said sealing surface (D′) being rotationally displaceable relative to said second ends of said respective sealing bristles ( 52 ); said sealing surface (D′) being formed by a circumferential surface of an intermediate sleeve arranged between said stator ( 10 ) and said rotor ( 20 ) for radially dividing said gap (S).   
     
     
         2 . The fluid flow machine according to  claim 1 , wherein said intermediate sleeve ( 60 ) divides said gap (S) radially into a first gap portion adjoining said sealing surface (D′) and a second gap portion adjoining a circumferential surface of said intermediate sleeve ( 60 ) remote of said sealing surface (D′), and wherein a radial extension of said second gap portion is greater than zero. 
     
     
         3 . The fluid flow machine according to  claim 1 , additionally comprising a flange mounting portion ( 62 ) at one of said stator and said rotor and wherein said intermediate sleeve ( 60 ) comprises a flange ( 62 ) for mounting said sleeve ( 60 ) at said flange mounting portion ( 22 ) of one of said stator ( 10 ) and said rotor ( 20 ) so as to be fixed with respect to rotation relative thereto. 
     
     
         4 . The fluid flow machine according to  claim 3 , wherein said flange ( 62 ) is detachably mounted at said flange mounting portion ( 22 ). 
     
     
         5 . The fluid flow machine according to  claim 3 , wherein said flange ( 62 ) comprises an annular flange surface at an axial end thereof and said flange mounting portion ( 22 ) comprises a mounting surface; and wherein said flange ( 62 ) is arranged at an axial end of said intermediate sleeve ( 60 ) so that said annular flange surface is contacting said mounting surface of said flange mounting portion ( 22 ) so as to be tight against fluid. 
     
     
         6 . The fluid flow machine according to  claim 1 , wherein said intermediate sleeve ( 60 ) comprises an outer circumferential surface ( 61 ) and wherein said rotor ( 20 ) is formed by a shaft, and said intermediate sleeve ( 60 ) is mounted on said rotor ( 20 ) so as to be fixed with respect to rotation relative thereto so that said sealing surface (D′) is formed by an outer circumferential surface ( 61 ) of said intermediate sleeve ( 60 ), and wherein said brush holder ( 51 ) is arranged at said stator ( 10 ) so as to be fixed with respect to rotation relative thereto. 
     
     
         7 . The fluid flow machine according to  claim 6 , wherein said intermediate sleeve ( 60 ) comprises an inner diameter and an inner circumferential surface; and said shaft comprises an outer diameter and an outer circumferential surface ( 21 ) and wherein said inner diameter of said intermediate sleeve ( 60 ) is greater than said outer diameter of said shaft so that an annular gap is formed between said inner circumferential surface of said intermediate sleeve ( 60 ) and said outer circumferential surface ( 21 ) of said shaft. 
     
     
         8 . The fluid flow machine according to  claim 1 , wherein said fluid flow machine is a turbo machine. 
     
     
         9 . The fluid flow machine according to  claim 8 , wherein said turbo machine is one of a gas turbine and a turbo compressor.