Sealing device, axial turbine and power plant

Abstract

In one embodiment, a sealing device includes seal fins provided on an inner circumferential surface of a stationary body or an outer circumferential surface of a rotating body so as to be adjacent to each other in an axial direction of the rotating body in a gap between the outer circumferential surface of the rotating body and the inner circumferential surface of the stationary body. The device further includes at least one opening member provided on the inner circumferential surface of the stationary body, the opening member being provided at a position between seal fins adjacent to each other in the axial direction, and having holes opened on a side of the inner circumferential surface of the stationary body.

1 . A sealing device comprising:
 seal fins provided on an inner circumferential surface of a stationary body or an outer circumferential surface of a rotating body so as to be adjacent to each other in an axial direction of the rotating body in a gap between the outer circumferential surface of the rotating body and the inner circumferential surface of the stationary body; and   at least one opening member provided on the inner circumferential surface of the stationary body, the opening member being provided at a position between seal fins adjacent to each other in the axial direction, and having holes opened on a side of the inner circumferential surface of the stationary body.   
     
     
         2 . The device of  claim 1 , wherein
 the seal fins are provided on the outer circumferential surface of the rotating body,   the inner circumferential surface of the stationary body has a first surface which is an inner circumferential surface of the opening member, and a second surface placed between opening members adjacent to each other in the axial direction, placed on an upstream side of the most upstream opening member, or placed on an downstream side of the most downstream opening member, and   the seal fins are provided at positions facing the second surface on the outer circumferential surface of the rotating body.   
     
     
         3 . The device of  claim 1 , wherein the opening member is divided into a plurality of members in a circumferential direction of the rotating body, and includes a reinforcing member between the divided members adjacent to each other in the circumferential direction. 
     
     
         4 . The device of  claim 1 , wherein a direction from bottom regions to opening regions of the holes of the opening member is inclined opposite to a rotation direction of the rotating body with respect to an inward normal direction of the inner circumferential surface of the stationary body. 
     
     
         5 . The device of  claim 1 , wherein an inner circumferential surface of the opening member has a step in a circumferential direction of the rotating body. 
     
     
         6 . The device of  claim 1 , wherein a slit extending in a circumferential direction of the rotating body is provided on an inner circumferential surface of the opening member. 
     
     
         7 . The device of  claim 1 , comprising at least one outside opening member provided on the inner circumferential surface of the stationary body, the outside opening member being provided at one or both of a position on a upstream side of the most upstream seal fin and a position on a downstream side of the most downstream seal fin, and having holes opened on the side of the inner circumferential surface of the stationary body. 
     
     
         8 . An axial turbine comprising:
 a stationary body including a casing for closing a working fluid and a stator vane provided on a side of an inner circumferential surface of the casing;   a rotating body including a rotor provided in the casing and a rotor vane provided on a side of an outer circumferential surface of the rotor;   and a sealing device provided in a gap between an outer circumferential surface of the rotating body and an inner circumferential surface of the stationary body so as to seal the working fluid,   the sealing device comprising:   seal fins provided on the inner circumferential surface of the stationary body or the outer circumferential surface of the rotating body so as to be adjacent to each other in an axial direction of the rotating body in the gap between the outer circumferential surface of the rotating body and the inner circumferential surface of the stationary body; and   at least one opening member provided on the inner circumferential surface of the stationary body, the opening member being provided at a position between seal fins adjacent to each other in the axial direction, and having holes opened on a side of the inner circumferential surface of the stationary body.   
     
     
         9 . The turbine of  claim 8 , wherein the working fluid is carbon dioxide in a supercritical state. 
     
     
         10 . A power plant comprising:
 a combustor configured to generate the carbon dioxide to be used as the working fluid;   the axial turbine of  claim 9  configured to operate by using the carbon dioxide as the working fluid; and   a power generator connected to the axial turbine.