Abstract: A high-pressure gas turbine for a turbomachine includes a nozzle guide vane assembly, an annular array of movable blades mounted downstream of the nozzle guide vane assembly, a bleed cavity, an upstream sealing element mounted on the nozzle guide vane assembly and a downstream sealing element mounted on the annular array of movable blades, a double baffle being formed by said upstream and downstream sealing elements, an external upstream cavity being formed in the upstream sealing element.

Abstract: A turbine engine nozzle extending about an axis and including a vane assembly mounted between an outer shroud and an inner shroud; and a position retaining device configured to be placed in an elastically prestressed state between the inner shroud and an inner platform of the vane assembly to apply a stress on the vane assembly towards the outer shroud. The contact between the inner shroud and the inner platform is obtained by one same surface of the position retaining device.

Abstract: A turbine including a casing and a nozzle including an outer metallic shroud secured to the casing, an inner metallic shroud, and a plurality of nozzle segments made of CMC forming a crown extending between the outer shroud and the inner shroud, each segment including a strut, an inner platform, an outer platform and at least one airfoil having a hollow profile traversed by the strut, wherein for each airfoil, the outer platform includes an axial stop extending in outward radial protrusion from the outer platform, and the outer metallic shroud comprises a complementary axial stop extending in inward radial protrusion from the outer metallic shroud, the axial stop being upstream and axially bearing against the complementary axial stop, and machined with an angle of machining chosen to adjust the orientation of said at least one blade of the segment with respect to the axial direction.

Abstract: A turbine ring assembly extending about an axis, includes a plurality of ring sectors made of ceramic matrix composite material forming a turbine ring and a ring support structure held by a turbine casing, each ring sector including a base from which an upstream lug and a downstream lug spaced axially from each other extend radially outwardly, the ring support structure including a spacer having a clamp against which the downstream lug of the ring sectors is held, a first upstream flange against which the upstream lug of the ring sectors is held, and upstream of the first upstream flange, a second upstream flange for absorbing forces against which the first upstream flange is held.

Abstract: A high-pressure gas turbine for a turbomachine includes a nozzle guide vane assembly, an annular array of movable blades mounted downstream of the nozzle guide vane assembly, a first recirculation cavity, a second recirculation cavity, and a bleed cavity. An upstream sealing element is mounted on the nozzle guide vane assembly and a downstream sealing element is mounted on the annular array of movable blades.

Abstract: A stator wheel for a turbomachine turbine. This wheel includes an inner shroud formed by an upstream portion and a downstream portion configured to be assembled with the blades by axial translation in a respective direction.

Abstract: An abradable coating includes a tubular cell structure, wherein the the tubular cell structure includes a fibrous reinforcement of discontinuous short fibers which is densified by a ceramic matrix.

Abstract: A turbine engine nozzle extending about an axis and including a vane assembly mounted between an outer shroud and an inner shroud; and a position retaining device configured to be placed in an elastically prestressed state between the inner shroud and an inner platform of the vane assembly to apply a stress on the vane assembly towards the outer shroud. The contact between the inner shroud and the inner platform is obtained by one same surface of the position retaining device.

Abstract: Turbine comprising a casing and a nozzle including a metal outer shroud integral with the casing, a metal inner shroud, and a plurality of nozzle sectors of CMC forming a ring extending between the metal outer shroud and the metal inner shroud, each sector including a mast, an inner platform, an outer platform and at least one airfoil having a hollow profile defining an inner recess, each of the inner and outer platforms having an opening communicating with said inner recess, and the mast passing through said openings and the inner recess and being attached to said casing and connected with said nozzle sector. The mast comprises at least one fastening projection having at least one portion extending from a radially outer end of the mast in a direction opposite to the center of the mast and in a plane orthogonal to the radial direction.

Abstract: A turbine comprising a casing and a nozzle including an outer metallic shroud (9) secured to the casing, an inner metallic shroud, and a plurality of nozzle segments (20) made of CMC forming a crown extending between the outer shroud (9) and the inner shroud, each segment including a strut (6), an inner platform, an outer platform and at least one airfoil having a hollow profile traversed by the strut (6). For each airfoil (20), the outer platform (26) comprises an axial stop (260) extending in outward radial protrusion from the outer platform (26), and the outer metallic shroud (9) comprises a complementary axial stop (96) extending in inward radial protrusion from the outer metallic shroud (9), the axial stop (260) being upstream and axially bearing against the complementary axial stop (96), and machined with an angle of machining chosen to adjust the orientation of said at least one blade of the segment with respect to the axial direction (DA).

Abstract: A turbine engine nozzle extending about an axis and including a vane assembly mounted between an outer shroud and an inner shroud; and a position retaining device configured to be placed in an elastically prestressed state between the inner shroud and an inner platform of the vane assembly to apply a stress on the vane assembly towards the outer shroud. The contact between the inner shroud and the inner platform is obtained by one same surface of the position retaining device.

Abstract: A turbomachine turbine nozzle extending around a central axis, including at least one radially outer shroud, at least one radially inner shroud, and at least one blade made of ceramic matrix composite material, distinct from the radially inner shroud and from the radially outer shroud, and extending radially between the radially inner shroud and the radially outer shroud, the blade being hollow and including a cavity opening at a radially inner end and at a radially outer end of the blade, the nozzle including at least one tubular mast arranged in the cavity of the blade and allowing routing the ventilation air passing through the cavity of the blade, the mast including a radially outer end attached to the radially outer shroud, and a radially inner end cooperating with a radial flange for positioning the radially inner shroud.

Abstract: A turbine ring assembly having ring segments made of ceramic matrix composite material and each having first and second attachment tabs and a cavity for the circulation of air flow, a metal support having a first bracket and a second bracket bearing axially upstream against the second tab, a first metal flange arranged upstream of the first bracket and having an inner periphery bearing axially downstream against the first tab and an outer periphery fastened to the first bracket, and air passage orifices formed in the inner periphery of the first flange and/or in the second bracket, the orifices configured to ensure that the air flow passes from the cavity to the outside of the assembly.

Abstract: A turbine assembly (1) comprising: —a plurality of turbine ring sectors (20) made of ceramic-matrix composite material, —a ring support structure (3), comprising an annular shroud (6), and in addition —a plurality of angular spacer sectors (70) together forming an annular spacer (7), said annular spacer (7) being, on the one hand, fixed to the turbine ring (2) and, on the other hand, fixed to said annular shroud (6), characterized in that said turbine assembly (1) comprises at least one air diffuser (8), which is configured to diffuse cooling air onto the radially outer face (212) of at least one of said turbine ring sectors (20), and in that said at least one air diffuser (8) is mounted by being nested on one of said angular spacer sectors (70), in a nested position.

Abstract: A nozzle for a turbomachine turbine. The nozzle includes blades made of ceramic matrix composite material, and at least one metal liner passing through a respective blade. The liner is connected in a sealed manner to a metal internal shroud so as to guide a ventilation fluid through the blade. The nozzle can be configured to maintain effective sealing in spite of the different thermal expansions of the blade and of the internal shroud.

Abstract: A device for cooling a turbine shroud comprising at least one annular flange configured to be attached to an annular radial collar of a shroud support structure being arranged upstream, with respect to a circulation direction of an air flow, of the turbine shroud, and comprising at least one cooling air circulation channel, a diffuser configured to be attached to said annular radial collar downstream of the annular flange and comprising at least one intake channel in fluid communication with the circulation channel of the annular flange, and comprising an injection cavity comprising a plurality of injection holes and being configured to inject on a radially external face of the shroud, via the injection holes, the cooling air originating in the intake channel, and a particle filter arranged on an inlet section of the circulation channel of the annular flange, the particle filter comprising a plurality of openings.

Abstract: A nozzle for a turbomachine turbine. The nozzle includes blades made of ceramic matrix composite material, and at least one metal liner passing through a respective blade. The liner is connected in a sealed manner to a metal internal shroud so as to guide a ventilation fluid through the blade. The nozzle can be configured to maintain effective sealing in spite of the different thermal expansions of the blade and of the internal shroud.

Abstract: The invention relates to a turbine assembly comprising: a plurality of ring sectors forming a ring; a support structure comprising a shroud from which there project radial flanges which serve to hold latching tabs of each ring sector; a stator positioned downstream of said ring and comprising a blade provided with a radially outer platform and extending axially opposite said ring; an annular space being defined between the ring, the support structure and the platform, this annular space having passing through it a leakage air current, the assembly comprising a hollow ring which occupies said annular space and which is shaped so as to collect, channel and expel said leakage air current, more specifically to channel and expel it into the radially inner region of said annular space.

Abstract: A turbomachine turbine nozzle extending around a central axis, including at least one radially outer shroud, at least one radially inner shroud, and at least one blade made of ceramic matrix composite material, distinct from the radially inner shroud and from the radially outer shroud, and extending radially between the radially inner shroud and the radially outer shroud, the blade being hollow and including a cavity opening at a radially inner end and at a radially outer end of the blade, the nozzle including at least one tubular mast arranged in the cavity of the blade and allowing routing the ventilation air passing through the cavity of the blade, the mast including a radially outer end attached to the radially outer shroud, and a radially inner end cooperating with a radial flange for positioning the radially inner shroud.

Abstract: A turbine assembly (1) comprising: —a plurality of turbine ring sectors (20) made of ceramic-matrix composite material, —a ring support structure (3), comprising an annular shroud (6), and in addition ?a plurality of angular spacer sectors (70) together forming an annular spacer (7), said annular spacer (7) being, on the one hand, fixed to the turbine ring (2) and, on the other hand, fixed to said annular shroud (6), characterized in that said turbine assembly (1) comprises at least one air diffuser (8), which is configured to diffuse cooling air onto the radially outer face (212) of at least one of said turbine ring sectors (20), and in that said at least one air diffuser (8) is mounted by being nested on one of said angular spacer sectors (70), in a nested position.