Alternatively, the sealing member may comprise an internal plate secured to the external plate, and the internal plate may comprise one or more tabs for connecting the external plate to the connection flange and/or to the adjacent connection tabs. The internal plate may comprise an internal upstream tab, the annular portion of the connection flange being interposed radially between the external upstream tab and the internal upstream tab. In other words, the internal upstream tab may be applied radially against the radially inner face of the annular portion of the connection flange. The internal plate may comprise a first internal side tab and a second internal side tab which are circumferentially opposite one another. The first connection tab may be radially interposed between the first external side tab and the first internal side tab. The second connection tab may be radially interposed between the second external side tab and the second internal side tab. In other words, the first internal side tab and the second internal side tab may be respectively applied radially against the radially inner face of the first connection tab and the second connection tab.

The internal plate and the external plate may be connected to one another by mechanical means or by a one-piece connection. One-piece connection is understood to mean that the internal plate and the external plate may be formed as an integral unit. For example, the internal plate and the external plate may be made in one piece by additive manufacturing. The external plate and the internal plate may form a unit assembly. The mechanical means may be welding, or a screw/nut or rivet attachment.

A turbine engine comprising an assembly as described above is also proposed.

BRIEF DESCRIPTION OF DRAWINGS

Other features, details and advantages will become apparent upon reading the detailed description below, and upon analyzing the appended drawings, in which:

FIG. 1 is a partial schematic half-section view in a longitudinal section plane of a turbine engine having a longitudinal axis of the prior art;

FIG. 2 is a partial schematic perspective view of an exhaust assembly of the turbine engine of FIG. 1;

FIG. 3 is a larger-scale schematic perspective view of an upstream end portion of the exhaust assembly of FIG. 2;

FIG. 4 is a partial schematic perspective view of an exhaust assembly according to the present description;

FIG. 5 is a schematic perspective view of a sealing member used in the exhaust assembly of FIG. 4 according to a first embodiment;

FIG. 6 is a schematic cross-section view in a longitudinal section plane of the sealing member of FIG. 5;

FIG. 7 is a schematic cross-section view in a section plane perpendicular to the longitudinal axis of the sealing member of FIG. 5;

FIG. 8 is an exploded schematic perspective view of the sealing member of FIG. 5;

FIG. 9 is a schematic perspective view of a sealing member used in the exhaust assembly of FIG. 4 according to a first variant of a second embodiment;

FIG. 10 is a schematic cross-section view in a longitudinal section plane of the sealing member of FIG. 9;

FIG. 11 is a schematic cross-section view in a section plane perpendicular to the longitudinal axis of the sealing member of FIG. 9;

FIG. 12 is an exploded schematic perspective view of the sealing member of FIG. 9;

FIG. 13 is an exploded schematic perspective view of a sealing member used in the exhaust assembly of FIG. 4 according to a second variant of the second embodiment;

FIG. 14 is a partial schematic perspective view of a sealing member used in the exhaust assembly of FIG. 4 according to a third variant of the second embodiment;

FIG. 15 includes FIGS. 15a, 15b, and 15c which each represent a schematic cross-section view of a sealing member used in the exhaust assembly of FIG. 4 in a respective variant of a third embodiment;

FIG. 16 includes FIG. 16a which is a schematic perspective view of the sealing member of FIG. 15a, and FIG. 16b which is a schematic perspective view of a fourth variant of the sealing member according to the third embodiment.

DESCRIPTION OF EMBODIMENTS

Reference is now made to FIG. 4. FIG. 4 represents an exhaust assembly for a turbine engine having a longitudinal axis X. In the following, orientation qualifiers such as “longitudinal”, “radial”, or “circumferential” are defined in reference to the longitudinal axis X. The relative qualifiers “upstream” and “downstream” are defined with respect to each other in relation to the flow of gases from upstream (UP) to downstream (DOWN) along the longitudinal axis X in the turbine engine.

The assembly firstly comprises an exhaust cone 40. Exhaust cone 40 comprises an upstream portion 40a of substantially axisymmetric shape around the longitudinal axis X, and a downstream portion (not shown) of conical shape along the longitudinal axis X with its cross-section decreasing in the downstream direction. Upstream portion 40a may be surrounded by an outer annular wall (not shown) for the flow of a primary air flow. Upstream portion 40a comprises an inner annular wall 44. Inner annular wall 44 and the outer annular wall of exhaust cone 40 may each be made of a ceramic matrix composite material. Such a material has a low density and thus allows reducing the mass of the assembly.

The assembly may comprise a turbine exhaust casing (not shown). The exhaust casing is arranged upstream of exhaust cone 40. The exhaust casing comprises in particular an inner shell.

The assembly also comprises a connection flange 46 arranged longitudinally between the exhaust casing and exhaust cone 40. Connection flange 46 comprises an annular portion 47 which is fixed to the exhaust casing. In particular, annular portion 47 of connection flange 46 comprises a radial annular wall 48 and a longitudinal annular wall 49. Longitudinal annular wall 49 extends longitudinally downstream from a radially outer end of radial annular wall 48. Radial annular wall 48 is intended to be fixed to the inner shell of the exhaust casing by screwing.

Connection flange 46 also comprises connection tabs 50. Each connection tab 50 extends downstream from longitudinal annular wall 49 of annular portion 47. Connection tabs 50 are distributed circumferentially around the longitudinal axis X. Here, connection tabs 50 are regularly distributed around the longitudinal axis X. Each connection tab 50 is further connected to inner annular wall 44 of exhaust cone 40 by screwing. To do so, inner annular wall 44 of exhaust cone 40 surrounds a downstream end portion of each of connection tabs 50.

A plurality of free spaces is thus defined. Each space is circumferentially delimited between a first connection tab 50 and a second connection tab 50 which are circumferentially successive, and longitudinally between annular portion 47 of connection flange 46 and the annular wall of exhaust cone 40.

Each connection tab 50 may have a shape such that the dimension in the circumferential direction is constant, from where it connects to annular portion 49 to at or near where it connects to inner annular wall 44, or such that the dimension in the circumferential direction of an upstream end portion of connection tab 50 is greater than the dimension in the circumferential direction of a downstream end portion of connection tab 50. In other words, the dimension in the circumferential direction of each connection tab 50 may narrow longitudinally in the downstream direction. Each space formed between two successive connection tabs 50 then has a trapezoidal shape in which the bases (i.e. the parallel sides) are spaced apart longitudinally. The small base of the trapezoidal shape of each space is coincident with a downstream end portion of annular portion 49 of the connection flange 46 which is located circumferentially between two circumferentially successive connection tabs 50. The large base of the trapezoidal shape of each space is coincident with an upstream end portion of the annular wall of exhaust cone 40 which is located circumferentially between two circumferentially successive connection tabs 50.

Finally, the assembly comprises a plurality of sealing members 60. Each sealing member 60 seals off a corresponding space as described above. Each sealing member 60 therefore allows locally sealing off one of the spaces formed circumferentially by two circumferentially successive connection tabs 50. This allows reducing the mass of the assembly in comparison to using an annular crown which surrounds all connection tabs 50 in order to seal off all the free spaces and which therefore has segments that do not contribute to the sealing.

In the following, a sealing member 60 according to a first embodiment is described in more detail with reference to FIGS. 5 to 8.

Sealing member 60 firstly comprises an external plate 70. External plate 70 may be made of metal. External plate 70 comprises an external sealing wall 71. External sealing wall 71 is arranged circumferentially between first connection tab 50 and second connection tab 50 which surround sealing member 60. External sealing wall 71 therefore participates in sealing closed the free space formed circumferentially between first connection tab 50 and second connection tab 50 and longitudinally between annular portion 47 of connection flange 46 and inner annular wall 44 of exhaust cone 40. For this purpose, external sealing wall 71 has a generally trapezoidal shape which is coincident with the trapezoidal shape of the sealed-off space.

External plate 70 further comprises a first external side tab 76 and a second external side tab 77. First external side tab 76 and second external side tab 77 extend circumferentially respectively from a first circumferential end and a second circumferential end of external sealing wall 71. The first circumferential end and the second circumferential end of external sealing wall 71 are circumferentially opposite one another. First external side tab 76 and second external side tab 77 are each applied in the radial direction respectively against the radially outer face of first connection tab 50 and the radially inner face of second connection tab 50. In the example illustrated, first external side tab 76 and second external side tab 77 have a dimension in the longitudinal direction that is identical to that of external sealing wall 71, i.e. identical to that of the sealed-off space.

External plate 70 also comprises an external upstream tab 78. External upstream tab 78 extends longitudinally upstream from external sealing wall 71. External upstream tab 78 is applied in the radial direction against longitudinal annular wall 49 of connection flange 46. During operation of the turbine engine, the pressure of the hot gases circulating in the turbine engine is higher radially externally to the assembly than radially internally. In other words, the pressure is higher radially externally to connection tabs 50 and inner annular wall 44 than within the volume defined radially internally to connection tabs 50 and inner annular wall 44. Thus, due to this pressure difference, a radially inward force is exerted on external plate 70 of each sealing member 60. External plate 70 is thus pressed against the radially outer face of first connection tab 50, second connection tab 50, and longitudinal annular wall 49 of connection flange 46 by the abutment of tabs 76, 77, 78. This thus allows better sealing of the corresponding free space.

Sealing member 60 also comprises an internal plate 80. Internal plate 80 may be made of metal. Internal plate 80 is connected to external plate 70. Internal plate 80 comprises an internal sealing wall 81. Internal sealing wall 81 is arranged circumferentially between first connection tab 50 and second connection tab 50. Internal sealing wall 81 therefore also contributes to sealing closed the free space formed circumferentially between first connection tab 50 and second connection tab 50 and longitudinally between annular portion 47 of connection flange 46 and the annular wall of exhaust cone 40. Internal sealing wall 81 has, for this purpose, a generally trapezoidal shape which is coincident with the trapezoidal shape of the sealed-off space. Internal plate 80 further comprises an internal downstream tab 88 which extends downstream longitudinally from internal sealing wall 81.

In this embodiment, sealing member 60 comprises a seal 90. Seal 90 may be made of a material resistant to high temperatures. In another configuration, seal 90 comprises a first portion 91 which is interposed in the radial direction, preferably clamped, between internal downstream tab 88 and a radially inner face of inner annular wall 44 of exhaust cone 40. This allows improving the radial sealing between sealing member 60 and inner annular wall 44 of exhaust cone 40. In addition, a simple radial abutment of first portion 91 of seal 90 against inner annular wall 44 of exhaust cone 40 reduces, or even prevents, the generation of mechanical stresses in inner annular wall 44 of exhaust cone 40. This reduces, or even prevents, the risk of damage to inner annular wall 44. The first portion of the seal may be held in place by a retainer which is part of or is fixed to plate 70. First portion 91 of seal 90 here is coincident with a downstream end portion of seal 90.

Seal 90 also comprises a second portion 92. Second portion 92 is different from first portion 91. Second portion 92 of seal 90 is arranged radially between external sealing wall 71 and internal sealing wall 81. Such an arrangement allows seal 90 to be fixed to external plate 70 and internal plate 80. Second portion 92 of seal 90 is generally flat. Second portion 92 of seal 90 comprises three holes 101 adapted to allow a connecting means 100 to pass through between external sealing wall 71 and internal sealing wall 81. Here, connecting means 100 between internal plate 80 and external plate 70 is a rivet type of mechanical means.

In the case of the first embodiment, second portion 92 of seal 90 extends circumferentially from first connection tab 50 to second connection tab 50 and longitudinally from annular portion 47 of connection flange 46 to an upstream end portion of inner annular wall 44 of exhaust cone 40.

Seal 90 comprises a first external side tab 93 and a second external side tab 94 which each extend circumferentially respectively from a first circumferential end and a second circumferential end of second portion 92 of seal 90. The first circumferential end and the second circumferential end of second portion 92 of seal 90 are circumferentially opposite one another. First external side tab 93 of seal 90 is radially clamped between first connection tab 50 and first external side tab 76 of external plate 70. Second external side tab 94 of seal 90 is radially clamped between second connection tab 50 and second external side tab 77 of external plate 70. This allows improving the sealing circumferentially between sealing member 60 and each among first connection tab 50 and second connection tab. In the illustrated example, the first side tab and the second side tab have a dimension in the longitudinal direction that is identical to that of external plate 70, i.e. identical to that of the sealed-off space.

Similarly, seal 90 comprises an external upstream tab 95 which extends longitudinally from an upstream end of second portion 92 of seal 90. External upstream tab 95 of seal 90 is clamped radially between longitudinal annular wall 49 of connection flange 46 and external upstream tab 95 of external plate 70. This allows improving the sealing longitudinally between sealing member 60 and connection flange 46.

Thus, in the first embodiment, the sealing relative to connection flange 46, first connection tab 50, and second connection tab 50 is improved by radially clamping tabs 93, 94, 95 of seal 90 between tabs 76, 77, 78 of external plate 70 on the one hand, and connection flange 46, first connection tab 50, and second connection tab 50 on the other hand.

Internal plate 80 further comprises a first internal side tab 86 and a second internal side tab 87. First internal side tab 86 and second internal side tab 87 respectively extend circumferentially from a first circumferential end and a second circumferential end of internal sealing wall 81. The first circumferential end and the second circumferential end of internal sealing wall 81 are circumferentially opposite one another. First internal side tab 86 and second internal side tab 87 are each applied, in the radial direction, respectively against a radially inner face of first connection tab 50 and a radially inner face of second connection tab 50. Due to the attachment of external plate 70 to internal plate 80, such an arrangement of internal side tabs 86, 87 allows increasing the clamping of each external side tab 93, 94 of seal 90 between the corresponding connection tab 50 and the corresponding external side tab 76, 77. This allows further improving the sealing produced by sealing member 60.

Each sealing member 60 may in particular be without any attachment relative to the corresponding first and second connection tabs 50. This allows giving a freedom of movement of sealing member 60 relative to first connection tab 50 and to second connection tab 50 when the two tabs thermally expand during operation of the turbine engine. This allows the stresses induced in the connection tabs to be reduced or even eliminated. Alternatively, external upstream tab 78 may be connected to annular portion 47 of connection flange 46 by mechanical means (screwing, welding in particular).

A second embodiment of sealing member 60 is now described with reference to FIGS. 9 to 12.

Sealing member 60 according to the second embodiment differs from the first embodiment in that external sealing wall 71 and internal sealing wall 81 each comprise a central portion 72, 82, an upstream end portion 75, 85, a first circumferential end portion 73, 83, and a second circumferential end portion 74, 84. First circumferential end portion 73, 83 and second circumferential end portion 74, 84 of each sealing wall 71, 81 are opposite each other in the circumferential direction relative to central portion 72, 82. In other words, central portion 72, 82 of each sealing wall 71, 81 is arranged circumferentially between the respective first circumferential end portion 73, 83 and second circumferential end portion 74, 84. “Upstream end portion” is also understood to refer to a portion arranged longitudinally upstream of the respective central portion 72, 82. In the present case, upstream end portion 75, 85 of each sealing wall 71, 81 is connected to and arranged upstream of the respective first circumferential end portion 73, 83 and second circumferential end portion 74, 84.

Central portion 72 of external sealing wall 71 bears radially against central portion 82 of internal sealing wall 81.

Thus, external sealing wall 71 and internal sealing wall 81 cooperate to form a first radial face and a second radial face. In the current case, the first radial face is formed by a radial shoulder 79 connecting central portion 72 of external sealing wall 71 to first circumferential end portion 73 of external sealing wall 71 and by a radial shoulder 89 connecting central portion 82 of internal sealing wall 81 to first circumferential end portion