Assembly for a turbine engine

Abstract

The invention relates to an assembly for a turbine engine of longitudinal axis (X), comprising: an exhaust cone (40) having an annular wall (44); an exhaust casing arranged upstream of the exhaust cone (40); a connection flange (46) disposed longitudinally between the exhaust casing and the exhaust cone (40), the connection flange (46) comprising an annular part (47), which is fixed to the exhaust casing, and connection tabs (50) extending longitudinally in the downstream direction from the annular part, the connection tabs (50) being distributed circumferentially about the longitudinal axis (X), each connection tab (50) being connected to the annular wall (44) of the exhaust cone (40); and a plurality of sealing members (60), each sealing member (60) tightly sealing a space delimited circumferentially between circumferentially consecutive first (50) and second connection tabs (50).

Description

Description Title: TURBOMACHINE SET technical field

[0001] This description relates to an exhaust assembly for a turbomachine. This description also relates to a turbomachine comprising such an assembly. Previous technique

[0002] Typically, as shown in Figure 1, a longitudinally oriented turbofan engine 10 comprises, from upstream to downstream in the direction of gas flow within the turbofan engine 10, a fan 12, a low-pressure compressor 14a, a high-pressure compressor 14b, a combustion chamber 16, a high-pressure turbine 18a, a low-pressure turbine 18b, and an exhaust nozzle 20. The high-pressure compressor 14b and the low-pressure compressor 14a are connected to a high-pressure turbine 18a and a low-pressure turbine 18b, respectively, by a shaft extending along the longitudinal direction of rotation of the turbofan engine shafts. Hereafter, orientation qualifiers such as "longitudinal," "radial," and "circumferential" are defined with reference to the longitudinal axis X.

[0003] The airflow entering the turbomachine is divided, downstream of the fan 12, into a primary annular airflow entering an annular duct 22a, called the primary duct, and a secondary annular airflow entering an annular duct 22b, called the secondary duct, which surrounds the primary annular air duct 22a. The low-pressure compressor 14a and the high-pressure compressor 14b, the combustion chamber 16, and the high-pressure turbine 18a and the low-pressure turbine 18b, are located, for the working parts, in the primary annular duct 22a.

[0004] An exhaust casing 30 is located directly at the outlet of the low-pressure turbine 28b. The exhaust casing 30 comprises a radially internal ferrule 32 and a radially external ferrule 34. An annular space formed between the internal and external ferrules forms part of the primary stream 22a at the outlet of the low-pressure turbine 18b. The internal ferrule of the exhaust casing can be metallic, for example, made of titanium alloy or Inconel®-type alloy.

[0005] The exhaust nozzle 20, or ejection nozzle, of the turbomachine 10 includes an exhaust assembly designed to optimize the flow of hot gases from the turbine. This assembly may also serve to absorb at least some of the noise generated by the interaction of these hot gases with the ambient air and with the flow of cold air from the blower.

[0006] This exhaust assembly includes an ejection cone 40 visible in figures 1, 2 and 3 which comprises an upstream part 40a, substantially axisymmetric in shape around the longitudinal axis X, and a downstream part 40b substantially conical in shape along the longitudinal axis X. The upstream part 40a includes an upstream annular wall 44.

[0007] The upstream annular wall 44 is connected to the downstream end of the inner ferrule 32 of the exhaust housing 30 via a connecting flange 46. The connecting flange 46 is metallic, for example, made of titanium alloy or Inconel®-type alloy. The connecting flange 46 has an annular portion 47 around the longitudinal axis X, from which flexible tabs 50 extend downstream, regularly spaced around its circumference. The annular wall 44 of the ejection cone 40 partially surrounds the tabs 50 and is connected to each of the tabs 50. Such flexible tabs 50 compensate for the differential expansion occurring between the inner ferrule 32 of the exhaust housing 30 and the ejection cone 40, these two elements being made of materials with different coefficients of thermal expansion.

[0008] In order not to reduce the performance of the turbomachine, it is necessary to seal the free spaces 51 formed circumferentially between each pair of circumferentially adjacent legs 50 and longitudinally between the downstream part of the annular flange 47 and the upstream annular wall 44 of the ejection cone 40 to prevent leakage of the flow of hot gases radially inwards.

[0009] It is therefore desirable to find a sealing solution which, on the one hand, adds little weight to the exhaust assembly, and on the other hand, which has a thermoelastic flexibility compatible with the thermomechanical deformations of the exhaust assembly, in particular those of the lugs 50 and the annular upstream wall 44. Summary

[0010] A longitudinal axis turbomachine assembly is proposed, comprising: - an ejection cone comprising an annular wall, - an exhaust housing arranged upstream of the ejection cone, and - a connecting flange arranged longitudinally between the exhaust casing and the ejection cone, the connecting flange comprising an annular portion which is fixed to the exhaust casing and connecting lugs extending longitudinally downstream from the annular portion, the connecting lugs being distributed circumferentially around the longitudinal axis, each connecting lug being connected to the annular wall of the ejection cone, - a plurality of sealing elements, each sealing element sealing in a way sealing a circumferentially delimited space between a first connecting leg and a second connecting leg circumferentially consecutive and longitudinally between the annular part of the connecting flange and the annular wall of the ejection cone, each sealing member comprising an external plate adapted to be partially applied in the radial direction on a radially external face of each of the first and second connecting legs.

[0011] Each sealing element allows for the local closure of only one of the spaces formed circumferentially between two circumferentially consecutive connecting lugs. Such an assembly of sealing elements has a reduced mass compared to a single annular sealing element positioned between the upstream housing ferrule and the annular wall of the ejection cone to cover all the connecting lugs and thus close all the open spaces.

[0012] Each sealing element must have at least one degree of freedom of movement in the circumferential direction between the two adjacent tabs, allowing it to slide when the two tabs move apart or closer together. Each sealing element must also have one degree of freedom in the longitudinal direction relative to the adjacent connecting tabs, the annular portion of the upstream flange, and the upstream wall of the ejection cone, allowing it to slide relative to neighboring parts during their thermomechanical deformation.

[0013] Furthermore, during turbomachine operation, the pressure of the hot gases circulating within the turbomachine can be higher radially outside the assembly than inside. Therefore, due to this pressure difference, a radially inward force is exerted on the outer plate of each sealing element, keeping it applied radially to the radially external face of the first and second connecting legs, thus providing a better seal in the corresponding gap. Thus, each sealing element may include an outer plate that is partially applied radially to a radially external face of each of the first and second connecting legs.

[0014] The annular portion of the connecting flange may include a radial annular wall and a longitudinal annular wall. The longitudinal annular wall may extend longitudinally downstream from the radial annular wall, including from a radially external end of the radial annular wall. Each connecting leg may extend longitudinally downstream from the longitudinal annular wall.

[0015] The radial annular wall can be fixed to the exhaust housing, in particular to an internal ferrule of the exhaust housing, notably by screwing.

[0016] The connecting legs can be distributed regularly around the longitudinal axis.

[0017] The ejection cone may include an upstream portion substantially axisymmetric about its longitudinal axis and a downstream portion conical about its longitudinal axis with a cross-section decreasing downstream. The upstream portion may include an outer annular wall for the flow of a primary airflow and an annular chamber arranged radially inside the outer annular wall. The annular chamber may include an inner annular wall arranged radially inside the outer annular wall of the ejection cone. This annular wall of the ejection cone may be either the outer or inner annular wall. This annular wall of the ejection cone may be radially opposite a downstream end portion of each of the connecting lugs. This annular wall of the ejection cone may be arranged radially inside or outside a downstream end portion of each of the connecting lugs.In particular, the annular wall of the ejection cone can surround a portion of the downstream end of each of the connecting lugs. This annular wall of the ejection cone can be made of a ceramic matrix composite material.

[0018] Each sealing element can be designed without fixed attachments relative to its corresponding first and second connecting lugs. This allows the sealing element freedom of movement relative to the first and second connecting lugs when these lugs expand thermally during turbomachine operation. This helps to limit, or even eliminate, the stresses induced in the mounting lugs.

[0019] The outer plate may include an external sealing wall, a first external lateral tab and a second external lateral tab, the external sealing wall being arranged circumferentially between the first and second connecting tabs, the first external lateral tab and the second external lateral tab extending circumferentially respectively from a first circumferential end and a second circumferential end of the external sealing wall which are circumferentially opposed to each other, the first external lateral tab and the second external lateral tab each being, in whole or in part, applied in the radial direction respectively to the radially external face of the first connecting tab and the radially external face of the second connecting tab.

[0020] The outer plate can be made of a metallic material. The external sealing wall can help to seal the space airtight. The wall The external seal may have an overall trapezoidal shape which coincides with the trapezoidal shape of the space sealed by the sealing element.

[0021] The outer plate may include an external upstream tab extending longitudinally upstream from the external sealing wall, the external upstream tab being, in whole or in part, applied in the radial direction to the annular portion of the connecting flange.

[0022] The outer plate of each sealing element is also held radially against the radially external face of the annular portion of the connecting flange, further improving the seal in the corresponding space. The external upstream tab can be connected to the annular portion of the connecting flange by mechanical means (screwing, welding, etc.).

[0023] Each sealing element may include an inner plate, the inner plate being connected to the outer plate, the inner plate comprising an internal sealing wall arranged circumferentially between the first connecting lug and the second connecting lug and an internal downstream tab which extends longitudinally downstream from the internal sealing wall.

[0024] According to one aspect, each sealing element may include a gasket. The gasket may bear against the annular wall of the ejection cone. The gasket may comprise at least one part positioned radially between the internal downstream tab of the internal plate and the annular wall of the ejection cone. The gasket may be a metallic, fibrous, or ceramic (CMC) braid. Such a gasket is thus resistant to high temperatures.

[0025] This improves the radial seal between the sealing element and the annular wall of the ejection cone. Furthermore, simple radial support of the first part of the seal on the annular wall of the ejection cone limits, or even prevents, the generation of mechanical stresses in the annular wall of the ejection cone. The inner plate can be made of a metallic material. The internal sealing wall can contribute to sealing the gap. The internal sealing wall can have a generally trapezoidal shape that coincides with the trapezoidal shape of the gap sealed by the sealing element. The first part of the seal can be inserted, preferably tightly, in the radial direction between the internal downstream tab and a radially internal or external face of the annular wall of the ejection cone. The first part of the seal can coincide with a downstream end portion of the seal.The first part of the joint may include a downstream branch of the joint. The joint may be made of a high-temperature resistant material.

[0026] The seal may have a second part separate from the first part, the second part of the seal being arranged radially between the outer sealing wall and the inner sealing wall. Such an arrangement allows the seal to be fixed to the outer and inner plates.

[0027] The second part of the joint can extend circumferentially from the first connecting lug to the second connecting lug and longitudinally from the annular part of the connecting flange to an upstream end portion of the annular wall of the ejection cone.

[0028] The joint may include a first external lateral tab and a second external lateral tab, each extending circumferentially respectively from a first circumferential end and a second circumferential end of the second part of the joint which are opposite each other, the first external lateral tab of the joint being interposed, preferably tightly, radially between the first connecting tab and the first external lateral tab of the outer plate, and the second external lateral tab of the joint being interposed tightly radially between the second connecting tab and the second external lateral tab of the outer plate.

[0029] This improves the circumferential seal between the sealing element and each of the first and second connecting tabs. The second part of the gasket can be generally flat. This second part may include one or more holes designed to allow the passage of a connecting element between the outer and inner sealing surfaces. The connecting element can be mechanical (screwing, riveting, welding, etc.). This allows for fastening between the outer and inner plates.

[0030] The inner plate may include a first internal lateral tab and a second internal lateral tab, the first internal lateral tab and the second internal lateral tab extending circumferentially respectively from a first circumferential end and a second circumferential end of the internal sealing wall which are circumferentially opposed to each other, the first internal lateral tab and the second internal lateral tab each being applied, in whole or in part, in the radial direction respectively on a radially internal face of the first connecting tab and a radially internal face of the second connecting tab.

[0031] The seal may comprise a first internal lateral tab and a second internal lateral tab, each extending circumferentially from a first circumferential end and a second circumferential end, respectively. of the second part of the seal, which are opposite each other, the first internal lateral tab of the seal being interposed, preferably tightly clamped, radially between the first connecting tab and the first internal lateral tab of the inner plate, and the second internal lateral tab of the seal being interposed, preferably tightly clamped, radially between the second connecting tab and the second internal lateral tab of the inner plate. This further improves the circumferential sealing between the sealing element and each of the first and second connecting tabs.

[0032] The seal may include an upstream tab extending longitudinally from an upstream end of the second part of the seal, the outer upstream tab of the seal being interposed, preferably clamped, radially between the annular portion of the connecting flange and the outer upstream tab of the outer plate. This further improves the longitudinal seal between the sealing element and the connecting flange.

[0033] The external sealing wall and the internal sealing wall can cooperate to form a first radial face and a second radial face. The second part of the seal can comprise a first lateral branch and a second lateral branch, each being at a downstream end connected to the first part of the seal, the first branch of the seal being interposed, preferably clamped, in the circumferential direction between the first radial face and the first connecting tab, and the second branch of the seal being interposed, preferably clamped, radially in the circumferential direction between the second radial face and the second connecting tab.

[0034] This improves the circumferential seal between the sealing element and each of the first and second connecting lugs. The first radial face and the second radial face can be circumferentially opposed to each other.

[0035] The external and internal sealing walls may each comprise a central portion, a first circumferential end portion, and a second circumferential end portion, opposite each other in the circumferential direction. The central portion of the external sealing wall is radially supported by the central portion of the internal sealing wall. The first radial face is formed by a radial shoulder connecting the central portion of the external sealing wall to the first circumferential end portion of the external sealing wall and / or by a radial shoulder connecting the central portion of the internal sealing wall to the first circumferential end portion of the internal sealing wall. The second radial face is formed by a radial shoulder connecting the central portion of the external sealing wall to the second circumferential end portion of the wall. external sealing and / or by a radial shoulder connecting the central part of the internal sealing wall to the second end part of the internal sealing wall.

[0036] The first branch can be arranged radially between the first circumferential end part of the external sealing wall and the first circumferential end part of the internal sealing wall, the second branch being arranged radially between the second circumferential end part of the external sealing wall and the second circumferential end part of the internal sealing wall.

[0037] The first arm can be inserted, preferably tightly, radially between the second circumferential end portion of the external sealing wall and the second circumferential end portion of the internal sealing wall. The second arm can be inserted, preferably tightly, radially between the second circumferential end portion of the external sealing wall and the second circumferential end portion of the internal sealing wall. The central part can be arranged circumferentially between the first circumferential end part and the second circumferential end part.

[0038] The external and internal sealing walls can cooperate to form an upstream radial face. The second part of the seal can include an upstream arm, with the first and second arms each connected at an upstream end to the upstream arm. The upstream arm of the second part of the seal is interposed, preferably clamped, in the longitudinal direction between the upstream radial face and the annular portion of the connecting flange. This improves the longitudinal seal between the sealing element and the connecting flange.

[0039] The external sealing wall and the internal sealing wall may each have a central part and an upstream end part, the central part of the external sealing wall being radially supported on the central part of the internal sealing wall, the upstream radial face is formed by a radial shoulder connecting the central part of the external sealing wall to the upstream end part of the external sealing wall and / or by a radial shoulder connecting the central part of the internal sealing wall to the upstream end part of the internal sealing wall.

[0040] The upstream arm of the seal can be arranged radially between the upstream end portion of the external sealing wall and the upstream end portion of the internal sealing wall. The upstream arm of the second part of the seal can be inserted, preferably tightly, radially between the upstream end portion of the external sealing wall and the upstream end portion of the internal sealing wall.

[0041] The central portion of the external sealing wall and the central portion of the internal sealing wall can be connected to each other mechanically or by a single-piece connection. A single-piece connection means that the central portion of the external sealing wall and the central portion of the internal sealing wall can be made from a single material. The external and internal plates can form a single unit. Alternatively, the mechanical connection can be by welding, or by fastening with a screw and nut or by rivet.

[0042] The external and internal sealing walls can be connected by a connecting piece arranged radially between the internal and external sealing walls. The connecting piece forms the first radial face, the second radial face, and, if applicable, the upstream radial face. The external and internal sealing walls can be connected to the connecting piece mechanically or by a one-piece connection. For example, the internal and external plates can be manufactured as a single unit using additive manufacturing.

[0043] According to a second aspect, the sealing element may be without a gasket.

[0044] The outer plate may include an external downstream tab extending longitudinally downstream from the external sealing wall. This external downstream tab is applied, in whole or in part, radially to the annular wall of the ejection cone. The radial support between the external downstream tab and the annular wall ensures a seal between the sealing element and the annular wall of the ejection cone. The external downstream tab is curved by being folded radially outward from the external sealing wall and longitudinally upstream. This improves the seal between the sealing element and the annular wall of the ejection cone.

[0045] The outer plate may include a radial spoiler extending radially outwards from the outer sealing wall. The radial spoiler may bear longitudinally against an upstream end of the annular wall of the ejection cone. This further improves the seal between the sealing element and the annular wall of the ejection cone.

[0046] The outer plate may include one or more hooks for connection to the connecting flange and / or adjacent connecting lugs. Each hook may extend radially inward from the outer plate. The outer plate may include an upstream hook engaging with the annular portion of the connecting flange, specifically with the longitudinal annular wall. The outer plate may include two lateral hooks, each lateral hook engaging with one of the adjacent connecting lugs.

[0047] Alternatively, the sealing element may include an inner plate integral with the outer plate. The inner plate may include one or more tabs for connecting the outer plate to the connecting flange and / or adjacent connecting tabs. The inner plate may include an internal upstream tab, with the annular portion of the connecting flange being radially interposed between the external upstream tab and the internal upstream tab. In other words, the internal upstream tab may be applied radially to the radially inner face of the annular portion of the connecting flange. The inner plate may include a first internal lateral tab and a second internal lateral tab circumferentially opposed to each other. The first connecting tab may be radially interposed between the first external lateral tab and the first internal lateral tab, respectively.The second connecting tab can be radially inserted between the second outer lateral tab and the second inner lateral tab. In other words, the first inner lateral tab and the second inner lateral tab can be radially applied to the radially inner face of the first and second connecting tabs, respectively.

[0048] The inner and outer plates can be joined mechanically or by a one-piece connection. A one-piece connection means that both the inner and outer plates can be made from a single piece of material. For example, the inner and outer plates can be manufactured as a single unit by additive manufacturing. The outer and inner plates can form a single unit. The mechanical connection can be a weld, or a fastener with a screw and nut or a rivet.

[0049] A turbomachine comprising an assembly as described above is also proposed. Brief description of the drawings

[0050] Other features, details, and advantages will become apparent upon reading the detailed description below and analyzing the attached drawings, on which:

[0051] Figure 1 is a partial schematic half-sectional view of a prior art longitudinal axis turbomachine in a longitudinal section plane;

[0052] Figure 2 is a partial schematic perspective view of an exhaust assembly of the turbomachine in Figure 1;

[0053] Figure 3 is a larger scale schematic perspective view of an upstream end portion of the exhaust assembly in Figure 2;

[0054] Figure 4 is a partial schematic perspective view of an escapement assembly as described herein;

[0055] Figure 5 is a schematic perspective view of a sealing element used in the exhaust assembly of Figure 4 according to a first embodiment;

[0056] Figure 6 is a schematic cross-sectional view of the sealing element of Figure 5 in a longitudinal cross-sectional plane;

[0057] Figure 7 is a schematic cross-sectional view of the sealing element of Figure 5 in a cross-sectional plane perpendicular to the longitudinal axis;

[0058] Figure 8 is a schematic exploded perspective view of the sealing element of Figure 5;

[0059] Figure 9 is a schematic perspective view of a sealing element used in the exhaust assembly of Figure 4 according to a first variant of a second embodiment;

[0060] Figure 10 is a schematic cross-sectional view of the sealing element of Figure 9 in a longitudinal cross-sectional plane;

[0061] Figure 11 is a schematic cross-sectional view of the sealing element of Figure 9 in a cross-sectional plane perpendicular to the longitudinal axis;

[0062] Figure 12 is a schematic exploded perspective view of the sealing element of Figure 9;

[0063] Figure 13 is a schematic exploded perspective view of a sealing element used in the exhaust assembly of Figure 4 according to a second variant of the second embodiment;

[0064] Figure 14 is a partial schematic perspective view of a sealing element used in the exhaust assembly of Figure 4 according to a third variant of the second embodiment;

[0065] Figure 15 includes figures 15a, 15b and 15c, each of which represents a schematic cross-sectional view of a sealing element used in the exhaust assembly of figure 4 according to a respective variant of a third embodiment;

[0066] Figure 16 includes Figure 16a, which is a schematic perspective view of the sealing element of Figure 15a, and Figure 16b, which is a schematic perspective view of a fourth variant of the sealing element according to the third embodiment. Description of the implementation methods

[0067] Reference is now made to Figure 4. Figure 4 represents an exhaust assembly for a turbomachine with a longitudinal axis X. In the following, orientation qualifiers, such as "longitudinal," "radial," or "circumferential," are defined with reference to the longitudinal axis X. The relative qualifiers "upstream" and "downstream" are defined with respect to each other with reference to the flow of gases from upstream (AM) to downstream (AV) in the turbomachine along the longitudinal axis X.

[0068] The assembly comprises, firstly, an ejection cone 40. The ejection cone 40 includes an upstream portion 40a, substantially axisymmetric about the longitudinal axis X, and a downstream portion (not shown) conical about the longitudinal axis X with a cross-section decreasing downstream. The upstream portion 40a may be surrounded by an external annular wall (not shown) for the flow of a primary air stream. The upstream portion 40a includes an upstream annular wall 44. Both the internal annular wall 44 and the external annular wall of the ejection cone 40 may be made of a ceramic matrix composite material. Such a material has a low density, thus allowing for a reduction in the overall mass.

[0069] The assembly may include a turbine exhaust housing (not shown). The exhaust housing is arranged upstream of the ejection cone 40. The exhaust housing notably includes an internal ferrule.

[0070] The assembly also includes a connecting flange 46 arranged longitudinally between the exhaust housing and the ejection cone 40. The connecting flange 46 includes an annular portion 47 that is fixed to the exhaust housing. In particular, the annular portion 47 of the connecting flange 46 comprises a radial annular wall 48 and a longitudinal annular wall 49. The longitudinal annular wall 49 extends longitudinally downstream from a radially external end of the radial annular wall 48. The radial annular wall 48 is intended to be fixed to the inner ferrule of the exhaust housing by screwing.

[0071] The connecting flange 46 also includes connecting lugs 50. Each connecting lug 50 extends downstream from the longitudinal annular wall 49 of the annular portion 47. The connecting lugs 50 are distributed circumferentially around the longitudinal axis X. Each connecting lug 50 is further connected to the inner annular wall 44 of the ejection cone 40 by screwing. For this purpose, the inner annular wall 44 of the ejection cone 40 surrounds a downstream end portion of each of the connecting lugs 50.

[0072] A plurality of free spaces is thus defined. Each space is circumferentially delimited between a first connecting leg 50 and a second leg of circumferentially consecutive and longitudinally connecting 50 between the annular part 47 of the connecting flange 46 and the annular wall of the ejection cone 40.

[0073] Each connecting leg 50 can have a shape such that its circumferential dimension is constant from its attachment to the annular portion 49 to near its attachment to the inner wall 44, or such that the circumferential dimension of an upstream end portion of the connecting leg 50 is greater than the circumferential dimension of a downstream end portion of the connecting leg 50. In other words, the circumferential dimension of each connecting leg 50 can narrow longitudinally downstream. Each space formed between two consecutive connecting legs 50 then has a trapezoidal shape with bases (i.e., parallel sides) spaced longitudinally apart.A small base of the trapezoidal shape of each space coincides with a downstream end portion of the annular part 47 of the connecting flange 46, which is located circumferentially between the two circumferentially consecutive connecting lugs 50. A large base of the trapezoidal shape of each space coincides with an upstream end portion of the annular wall of the ejection cone 40, which is located circumferentially between the two circumferentially consecutive connecting lugs 50.

[0074] Finally, the assembly comprises a plurality of sealing elements 60. Each sealing element 60 hermetically seals a corresponding space as described above. Each sealing element 60 thus allows for the local sealing of only one of the spaces formed circumferentially by two consecutive circumferential connecting tabs 50. This reduces the overall mass compared to using an annular ring that surrounds all the connecting tabs 50 to seal all the open spaces and which, in fact, has segments that do not contribute to the sealing.

[0075] In the following, a sealing element 60 is described in more detail according to a first embodiment with reference to figures 5 to 8.

[0076] The sealing element 60 comprises, firstly, an outer plate 70. The outer plate 70 may be made of a metallic material. The outer plate 70 includes an external sealing wall 71. The external sealing wall 71 is arranged circumferentially between the first connecting lug 50 and the second connecting lug 50 that surround the sealing element 60. The external sealing wall 71 thus contributes to the hermetic sealing of the free space formed circumferentially between the first connecting lug 50 and the second connecting lug 50 and longitudinally between the annular portion 47 of the connecting flange 46 and the internal annular wall 44 of the cone ejection 40. The external sealing wall 71 has for this purpose a generally trapezoidal shape which coincides with the trapezoidal shape of the sealed space.

[0077] The outer plate 70 further comprises a first external lateral tab 76 and a second external lateral tab 77. The first external lateral tab 76 and the second external lateral tab 77 extend circumferentially from a first circumferential end and a second circumferential end, respectively, of the external sealing wall 71. The first circumferential end and the second circumferential end of the external sealing wall 71 are circumferentially opposite to each other. The first external lateral tab 76 and the second external lateral tab 77 are each applied radially to the radially external face of the first connecting tab 50 and the radially external face of the second connecting tab 50, respectively.In the illustrated example, the first external lateral tab 76 and the second external lateral tab 77 have a dimension in the longitudinal direction identical to that of the external sealing wall 71, i.e. identical to that of the sealed space.

[0078] The outer plate 70 also includes an external upstream tab 78. The external upstream tab 78 extends longitudinally upstream from the external sealing wall 71. The external upstream tab 78 is applied radially to the longitudinal annular wall 49 of the connecting flange 46. During the operation of the turbomachine, the pressure of the hot gases circulating within the turbomachine is higher radially outside the assembly than inside. In other words, the pressure is higher radially outside the connecting tabs 50 and the internal annular wall 44 than in the volume defined radially inside the connecting tabs 50 and the internal annular wall 44. Thus, due to this pressure difference, a radially inward force is exerted on the outer plate 70 of each sealing element 60.The outer plate 70 is then pressed against the radially external face of the first connecting lug 50, the second connecting lug 50 and the longitudinal annular wall 49 of the connecting flange 46 by the supports of the tabs 76, 77, 78. This allows for better sealing at the level of the corresponding free space.

[0079] The sealing element 60 also includes an inner plate 80. The inner plate 80 can be made of a metallic material. The inner plate 80 is connected to the outer plate 70. The inner plate 80 includes an internal sealing wall 81. The internal sealing wall 81 is arranged circumferentially between the first connecting tab 50 and the second connecting tab 50. The internal sealing wall 81 therefore also contributes to the airtight sealing of the free space formed circumferentially between the first connecting tab 50 and the second connecting tab 50 and longitudinally between The annular portion 47 of the connecting flange 46 and the annular wall of the ejection cone 40. The internal sealing wall 81 has a generally trapezoidal shape that coincides with the trapezoidal shape of the sealed space. The internal plate 80 also includes an internal downstream tab 88 that extends longitudinally downstream from the internal sealing wall 81.

[0080] In this embodiment, the sealing element 60 comprises a gasket 90. The gasket 90 can be made of a high-temperature resistant material. In another configuration, the gasket 90 comprises a first portion 91 which is interposed, preferably tightly, in the radial direction between the internal downstream tab 88 and a radially internal face of the internal annular wall 44 of the ejection cone 40. This improves the radial seal between the sealing element 60 and the internal annular wall 44 of the ejection cone 40. Furthermore, simple radial support of the first portion 91 of the gasket 90 on the internal annular wall 44 of the ejection cone 40 limits, or even prevents, the generation of mechanical stresses in the internal annular wall 44 of the ejection cone 40. This limits, or even prevents, the risk of damage to the internal annular wall 44.The first part of the joint can be held in place by a retainer forming part of or fixed to the plate 70. The first part 91 of the joint 90 coincides here with a downstream end part of the joint 90.

[0081] The seal 90 also includes a second part 92. This second part 92 is separate from the first part 91. The second part 92 of the seal 90 is arranged radially between the outer sealing wall 71 and the inner sealing wall 81. This arrangement allows the seal 90 to be fixed to the outer plate 70 and the inner plate 80. The second part 92 of the seal 90 is generally flat. The second part 92 of the seal 90 includes three holes 101 adapted to allow the passage of a connecting means 100 between the outer sealing wall 71 and the inner sealing wall 81. The connecting means 100 between the inner plate 80 and the outer plate 70 is a mechanical means of the rivet type.

[0082] In the case of the first embodiment, the second part 92 of the joint 90 extends circumferentially from the first connecting leg 50 to the second connecting leg 50 and longitudinally from the annular part 47 of the connecting flange 46 to an upstream end portion of the internal annular wall 44 of the ejection cone 40.

[0083] The seal 90 comprises a first external lateral tab 93 and a second external lateral tab 94, each extending circumferentially from a first circumferential end and a second circumferential end respectively of the second part 92 of the seal 90. The first circumferential end and the second The circumferential ends of the second part 92 of the joint 90 are circumferentially opposed to each other. The first external lateral tab 93 of the joint 90 is radially clamped between the first connecting lug 50 and the first external lateral tab 76 of outer plate 70. The second outer lateral tab 94 of the seal 90 is radially clamped between the second connecting tab 50 and the second outer lateral tab 77 of the outer plate 70. This improves the circumferential seal between the sealing element 60 and each of the first connecting tab 50 and the second connecting tab. In the illustrated example, the first lateral tab and the second lateral tab have the same dimension in the longitudinal direction as the outer plate 70, i.e., the same as the sealed space.

[0084] Similarly, the seal 90 includes an external upstream tab 95 which extends longitudinally from an upstream end of the second part 92 of the seal 90. The external upstream tab 95 of the seal 90 is radially clamped between the longitudinal annular wall 49 of the connecting flange 46 and the external upstream tab 95 of the external plate 70. This improves the longitudinal sealing between the sealing element 60 and the connecting flange 46.

[0085] Thus, in the first embodiment, the sealing with respect to the connecting flange 46, the first connecting lug 50 and the second connecting lug 50 is improved by a radial tightening of the tabs 93, 94, 95 of the seal 90 between, on the one hand, the tabs 76, 77, 78 of the external plate 70 and, on the other hand, the connecting flange 46, the first connecting lug 50 and the second connecting lug 50.

[0086] The inner plate 80 further comprises a first internal lateral tab 86 and a second internal lateral tab 87. The first internal lateral tab 86 and the second internal lateral tab 87 extend circumferentially from a first circumferential end and a second circumferential end, respectively, of the internal sealing wall 81. The first circumferential end and the second circumferential end of the internal sealing wall 81 are circumferentially opposite to each other. The first internal lateral tab 86 and the second internal lateral tab 87 are each applied, in the radial direction, respectively, to a radially internal face of the first connecting tab 50 and a radially internal face of the second connecting tab 50.Due to the attachment of the outer plate 70 to the inner plate 80, this arrangement of internal side tabs 86, 87 increases the clamping force of each external side tab 93, 94 of the seal 90 between the corresponding connecting tab 50 and the corresponding external side tab 76, 77. This further improves the sealing produced by the sealing element 60.

[0087] Each sealing element 60 may, in particular, be unfixed relative to the corresponding first and second connecting lugs 50. This allows the sealing element 60 freedom of movement relative to the first and second connecting lugs 50 when these lugs expand thermally during the operation of the turbomachine. This makes it possible to limit, or even eliminate, the stresses induced in the fixing lugs. Alternatively, the external upstream tab 78 may be connected to the annular portion 47 of the connecting flange 46 by mechanical means (screwing, welding, etc.).

[0088] A second embodiment of the sealing element 60 is now described with reference to figures 9 to 12.

[0089] The sealing element 60 according to the second embodiment differs from the first embodiment in that the external sealing wall 71 and the 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. The first circumferential end portion 73, 83 and the second circumferential end portion 74, 84 of each sealing wall 71, 81 are opposite each other in the circumferential direction with respect to the central portion 72, 82. In other words, the central portion 72, 82 of each sealing wall 71, 81 is arranged circumferentially between the first end portions 73, 83 and the second end portions 74, 84. circumferential end 74, 84 respectively.The term "upstream end part" also refers to a part arranged longitudinally upstream of the respective central part 72, 82. In the present case, the upstream end part 75, 85 of each sealing wall 71, 81 is connected to and arranged upstream of the respective first circumferential end part 73, 83 and second circumferential end part 74, 84.

[0090] The central part 72 of the external sealing wall 71 is radially supported on the central part 82 of the internal sealing wall 81.

[0091] Thus, the external sealing wall 71 and the internal sealing wall 81 cooperate to form a first radial face and a second radial face. In this case, the first radial face is formed by a radial shoulder 79 connecting the central part 72 of the external sealing wall 71 to the first circumferential end portion 73 of the external sealing wall 71, and by a radial shoulder 89 connecting the central part 82 of the internal sealing wall 81 to the first circumferential end portion 83 of the internal sealing wall 81. Similarly, the second radial face is formed by a radial shoulder 79 connecting the central part 72 of the external sealing wall 71 to the second part circumferential end 74 of the external sealing wall 71 and by a radial shoulder 89 connecting the central part 82 of the internal sealing wall 81 to the second circumferential end part 84 of the internal sealing wall 81. The first radial face and the second radial face are therefore circumferentially opposed to each other.

[0092] Also, the external sealing wall 71 and the internal sealing wall 81 cooperate to form an upstream radial face. The upstream radial face is formed by a radial shoulder 79 connecting the central part 72 of the external sealing wall 71 to the upstream end part 75 of the external sealing wall 71 and by a radial shoulder 89 connecting the central part 82 of the internal sealing wall 81 to the upstream end part 85 of the internal sealing wall 81.

[0093] The sealing element 60 according to the second embodiment also differs from the first embodiment in that the second part 92 of the seal 90 comprises a first lateral branch 95, a second lateral branch 96, and an upstream branch 97. The first lateral branch 95 and the second lateral branch 96 are each connected at a downstream end to the first part 91 of the seal 90 and at an upstream end to the upstream branch 97. The first part 91 of the seal 90 comprises (in this case, forms) a downstream branch of the seal 90. Thus, notably, the seal 90 is of the peripheral type.

[0094] The first lateral arm 95 of the seal 90 is clamped circumferentially between the first radial face and the first connecting tab 50. This improves the circumferential seal between the sealing element 60 and the first connecting tab 50. The first lateral arm 95 is also arranged radially between the first circumferential end portion 73 of the external sealing wall 71 and the first circumferential end portion 83 of the internal sealing wall 81. The second lateral arm 96 of the seal 90 is clamped radially in the circumferential direction between the second radial face and the second connecting tab 50. This improves the circumferential seal between the sealing element 60 and the second connecting tab 50.The second lateral branch 96 is also arranged radially between the second circumferential end part 74 of the external sealing wall 71 and the second circumferential end part 84 of the internal sealing wall 81.

[0095] The upstream arm 97 is clamped longitudinally between the upstream radial face and the longitudinal annular wall 49 of the connecting flange 46. This improves the longitudinal seal between the sealing element 60 and the longitudinal annular wall 49 of the connecting flange 46. The upstream arm 97 of the seal 90 is also arranged radially between the upstream end portion 75 of the wall external sealing 71 and the upstream end part 85 of the internal sealing wall 81. Thus, remarkably, the seal 90 surrounds the central part 72, 82 of each of the internal sealing wall 71 and the external sealing wall 82.

[0096] Thus, in the second embodiment, the sealing with respect to the connecting flange 46, the first connecting lug 50 and the second connecting lug 50 is ensured by a circumferential tightening of the arms 95, 96, 97 of the seal 90 between, on the one hand, the inner plate 70 and the outer plate 80 and, on the other hand, the connecting flange 46, the first connecting lug 50 and the second connecting lug 50.

[0097] Finally, the central part 72 of the external sealing wall 71 and the central part 82 of the external sealing wall 71 are connected to each other by a mechanical means. The mechanical means may be a weld, or a fastening by screw and nut or by rivet.

[0098] Also, remarkably in the second embodiment, the first external lateral tongue 76 and the second external lateral tongue 77 have a dimension in the longitudinal direction lower than that of the external sealing wall 71, i.e. lower than that of the sealed space.

[0099] According to an alternative embodiment of the sealing element 60 of the second embodiment shown in Figure 13, the central portion 72 of the external sealing wall 71 and the central portion 82 of the external sealing wall 71 are connected to each other by a single-piece joint. A single-piece joint is understood to mean that the central portion 72 of the external sealing wall 71 and the central portion 82 of the external sealing wall 71 are formed from a single piece of material. The external plate 70 and the internal plate 80 thus form a single unit.

[0100] According to another embodiment of the sealing element 60 of the second embodiment shown in Figure 14, the external sealing wall 71 and the internal sealing wall 81 are connected by an intermediate connecting piece 110 arranged radially between the internal sealing wall 81 and the external sealing wall 71. The first radial face, the second radial face and the upstream radial face are formed by the intermediate connecting piece 110. The external sealing wall 71 and the internal sealing wall 81 can be connected to the intermediate connecting piece 110 by mechanical means or by a monobloc connection.

[0101] A third embodiment of the sealing element 60 is now described with reference to figures 15 and 16. According to the third embodiment, the sealing element 60 is without a gasket.

[0102] The external plate 70 may include an upstream external tab, a first external lateral tab and / or a second external lateral tab as described with reference to the first embodiment.

[0103] As shown in Figure 15, the outer plate 70 includes an external downstream tab 79 that extends longitudinally downstream from the external sealing wall 71. The external downstream tab 79 is applied radially outwards to the annular wall 44 of the ejection cone 40. Alternatively, the external downstream tab 79 can be, in whole or in part, applied radially inwards to the annular wall 44 of the ejection cone 40. The radial support between the external downstream tab 79 and the annular wall 44 ensures a seal between the sealing element 60 and the annular wall 44 of the ejection cone 40.

[0104] According to the variant shown in Figure 15a, the external downstream tab 79 is straight, or in other words, flat. According to the variant shown in Figure 15b, the external downstream tab 79 is curved, being folded radially outwards relative to the external sealing wall and longitudinally upstream. In other words, the external downstream tab is folded radially outwards and longitudinally upstream. This improves the seal between the sealing element and the annular wall of the ejection cone.

[0105] According to the variant in Figure 15c, the outer plate 70 includes a radial spoiler 61 which extends radially outwards from the outer sealing wall 71. The radial spoiler 61 bears in the longitudinal direction on an upstream end of the annular wall 44 of the ejection cone 40. This improves the seal between the sealing element 60 and the annular wall 44 of the ejection cone 40.

[0106] As shown in Figure 16a, the outer plate 70 may include one or more hooks 120 for connecting to the connecting flange 46 and / or the adjacent connecting lugs 50 to improve sealing. Each hook 120 is radially connected to the inside of the outer plate 70. Here, the outer plate 70 includes an upstream hook 120 engaging with the annular portion 47 of the connecting flange 46, specifically with the longitudinal annular wall 49. The outer plate 70 also includes two lateral hooks 120, each lateral hook 120 engaging with one of the adjacent connecting lugs 50. Thus, the annular portion 47 of the connecting flange 46 and the connecting lugs 50 are clamped between the respective hook 120 and the outer plate. Each hook 120 may be elastic.

[0107] Alternatively, according to the variant in Figure 16b, the sealing element may comprise an inner plate 80 integral with the outer plate 70. The inner plate includes one or more tabs for connecting the outer plate 70 to the connecting flange 46 and / or the adjacent connecting lugs 50. The inner plate 80 here comprises a The internal upstream tab 89, the longitudinal annular wall 49 of the annular portion 47 of the connecting flange 46 being radially interposed between the external upstream tab 78 and the internal upstream tab 89. In other words, the internal upstream tab 89 can be applied radially to the radially internal face of the longitudinal annular wall 49 of the annular portion 47 of the connecting flange 46. The internal plate 80 also includes a first internal lateral tab 86 and a second internal lateral tab 87 circumferentially opposed to each other. The first connecting tab 50 can be radially interposed between the first external lateral tab 76 and the first internal lateral tab 86. The second connecting tab 50 can be radially interposed between the second external lateral tab 77 and the second internal lateral tab 87.In other words, the first internal lateral tab 86 and the second internal lateral tab 87 can respectively be applied radially to the radially internal face of the first connecting tab 50 and the second connecting tab 50.

[0108] The inner plate 70 and the outer plate 80 can be joined to each other mechanically or by a one-piece connection. A one-piece connection means that the inner plate 70 and the outer plate 80 can be made from a single piece of material. For example, the inner plate 70 and the outer plate 80 can be produced as a single unit by additive manufacturing. The outer plate 70 and the inner plate 80 can thus form a single assembly. The mechanical connection can be by welding, or by fastening with a screw and nut or by rivet.

Claims

Demands

1. Assembly for a longitudinal (X) axis turbomachine comprising: - an ejection cone (40) comprising an annular wall (44), - an exhaust casing arranged upstream of the ejection cone (40), and - a connecting flange (46) arranged longitudinally between the exhaust housing and the ejection cone (40), the connecting flange (46) comprising an annular portion (47) which is fixed to the exhaust housing and connecting lugs (50) extending longitudinally downstream from the annular portion, the connecting lugs (50) being distributed circumferentially around the longitudinal axis (X), each connecting lug (50) being connected to the annular wall (44) of the ejection cone (40), - a plurality of sealing members (60), each sealing member (60) sealing in a circumferentially defined space between a first connecting leg (50) and a second connecting leg (50) circumferentially consecutive and longitudinally between the annular part (47) of the connecting flange (46) and the annular wall (44) of the ejection cone (40), each sealing member (60) comprising an external plate (70) adapted to be partially applied in the radial direction on a radially external face of each of the first connecting leg (50) and second connecting leg (50).

2. Assembly according to claim 1, wherein the outer plate (70) comprises an outer sealing wall (71), a first outer lateral tab (76) and a second outer lateral tab (77), the outer sealing wall (71) being arranged circumferentially between the first and second connecting tabs (50), the first outer lateral tab (76) and the second outer lateral tab (77) extending circumferentially respectively from a first circumferential end and a second circumferential end of the outer sealing wall (71) which are circumferentially opposite to each other, the first outer lateral tab (76) and the second outer lateral tab (77) each being, in whole or in part, applied in the radial direction respectively to the radially outer face of the first connecting tab (50) and the radially outer face of the second connecting tab (50).

3. Assembly according to the preceding claim, wherein the outer plate (70) comprises an external upstream tab (78) which extends longitudinally upstream from the external sealing wall (71), the external upstream tab (78) being, in whole or in part, applied in the radial direction to the annular part (47) of the connecting flange (46).

4. Assembly according to claim 2 or 3, wherein each sealing member (60) comprises an inner plate (80), the inner plate (80) being connected to the outer plate (70), the inner plate (80) comprising an internal sealing wall (81) arranged circumferentially between the first connecting lug (50) and the second connecting lug (50) and an internal downstream tab (88) extending longitudinally downstream from the internal sealing wall (81)

5. Assembly according to any one of the preceding claims, wherein each sealing member (60) comprises a seal (90), the seal (90) being in contact with the annular wall (44) of the ejection cone (40).

6. Together according to the preceding claim, claim 4 applying, wherein the seal (90) comprises at least a first part (91) which is positioned in the radial direction between the internal downstream tab (88) of the internal plate (80) and the annular wall (44) of the ejection cone (40).

7. Assembly according to the preceding claim, wherein the seal (90) comprises a second part (92) distinct from the first part (91), the second part (92) of the seal (90) being arranged radially between the external sealing wall (71) and the internal sealing wall (81).

8. Assembly according to the preceding claim, wherein the second part (92) of the joint (90) extends circumferentially from the first connecting lug (50) to the second connecting lug (50) and longitudinally from the annular part (47) of the connecting flange (46) to an upstream end portion of the annular wall (44) of the ejection cone (40).

9. Assembly according to claim 7 or 8, wherein the joint (90) comprises a first external lateral tab (93) and a second external lateral tab (94) which each extend circumferentially respectively from a first circumferential end and a second circumferential end of the second part (92) of the joint (90) which are opposite each other, the first external lateral tab (93) of the joint being positioned radially between the first connecting tab (50) and the first external lateral tab (76) of the external plate (70), and the second external lateral tab (94) of the joint (90) being positioned radially between the second connecting tab (50) and the second external lateral tab (77) of the external plate (70).

10. Assembly according to claim 7, wherein the external sealing wall (71) and the internal sealing wall (81) cooperate to form a first radial face and a second radial face, and wherein the second part (92) of the seal (90) includes a first lateral branch (96) and a second lateral branch (96) each being at a downstream end connected to the first part (91) of the joint (90), the first lateral branch (95) of the joint (90) being positioned in the circumferential direction between the first radial face and the first connecting leg (50) and the second lateral branch (96) of the joint (90) being positioned radially in the circumferential direction between the second radial face and the second connecting leg (50).

11. Assembly according to the preceding claim, wherein the external sealing wall (71) and the internal sealing wall (81) cooperate to form an upstream radial face, and wherein the second part (92) of the joint (90) comprises an upstream branch (97), the first lateral branch (95) and the second lateral branch (96) each being at an upstream end connected to the upstream branch (97), the upstream branch (97) of the second part (92) of the joint (90) being positioned in the longitudinal direction between the upstream radial face and the annular part (47) of the connecting flange (46).

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