Gas turbine ventilation circuitry

Abstract

A ventilation circuit of a turbomachine turbine rotor having a turbine disk and an upstream flange disposed upstream from a combustion chamber from which it is spaced apart by a cavity. A first cooling air circuit delivers air into the cavity via main injectors and holes in the flange. A second cooling air circuit delivers air through enclosures delimited by the combustion chamber inner casing and the rotor via a discharge labyrinth, an under-injector labyrinth, and at least one labyrinth downstream from the main injectors between an annular structure and the flange. Three single-wiper labyrinths delimiting two cavities upstream from the venting cavity of the turbine disk are provided downstream from the main injectors. One of the cavities is fed with air from the second circuit upstream from the under-injector labyrinth by bore holes in the annular structure sloping tangentially in the rotation direction of the rotor.

1 - 5 . (canceled)  
   
   
       6 . A turbomachine comprising: 
 a sealing device between a turbine rotor and an inner casing of a combustion chamber, the turbine rotor comprising: 
 a turbine disk presenting an upstream clamping annulus for fastening it to a downstream cone of a compressor, and  
 a flange disposed upstream from the disk and spaced apart from the disk by a cavity, the flange including an inside bore traversed by the upstream clamping annulus of the disk and an upstream clamping annulus so it can be fastened onto the downstream cone;  
   a first air circuit secured to the inner casing to deliver a first flow of cooling into the cavity via main injectors and holes made in the flange;    the sealing device comprising a discharge labyrinth between the downstream cone and the inner casing, a main under-injector labyrinth disposed between the flange and an inside wall of the first air circuit, and at least one over-injector labyrinth disposed between the flange and an annular structure provided between an outside wall of the first air circuit and the inner casing, a second flow of cooling air flowing inside a second circuit defined by enclosures delimited by the inner casing and the rotor, by the labyrinths, and being evacuated in part in the upstream venting cavity of the disk, wherein downstream from the main injectors in flow direction of the second flow of cooling air, the sealing device comprises at least three labyrinths radially spaced apart, being disposed between the flange and the annular structure.    
   
   
       7 . A turbomachine according to  claim 6 , wherein each of the three labyrinths comprises a single wiper.  
   
   
       8 . A turbomachine according to  claim 6 , wherein one of the annular cavities lying between two consecutive labyrinths out of the three labyrinths is fed by cooling air coming from the second circuit upstream from the under-injector labyrinth.  
   
   
       9 . A turbomachine according to  claim 8 , wherein the flow of cooling air is set into rotation in a same direction as rotation of the rotor by secondary injectors.  
   
   
       10 . A turbomachine according to  claim 9 , wherein the secondary injectors are made in a form of sloping holes formed in the annular structure.