ASSEMBLY FOR A TURBOMACHINE

Abstract

An assembly for a turbomachine includes an exhaust cone and an exhaust casing having an annular inner shell. The exhaust cone and the exhaust casing can extend about a first axis, the exhaust cone can have an outer surface extending in the projection of the inner shell, the exhaust cone can be connected to the exhaust casing by means of a flange, the flange having an upstream portion fastened to the exhaust casing and lugs extending downstream from said upstream portion, and the exhaust cone can be fastened to the lugs. The flange can be sectorized and include of a plurality of angular sectors arranged so as to be circumferentially adjacent, with each flange sector having at least one lug extending rectilinearly along a second axis parallel to the first axis.

Claims

1. An assembly for a turbomachine, comprising: an exhaust cone; and an exhaust case including an annular inner shell, the exhaust cone and the exhaust case extending about a first axis, the exhaust cone including an outer surface extending in the projection of the inner shell, the exhaust cone being connected to the exhaust case via a flange, the flange including an upstream portion fastened to the exhaust case and lugs extending downstream from the upstream portion, the exhaust cone being fastened to the lugs, wherein the flange is segmented and consists of angular segments arranged circumferentially adjacent, each flange segment including at least one lug extending in a rectilinear manner along a second axis parallel with the first axis.

2. The assembly of claim 1, wherein each flange segment extends over an angular range less than 180.

3. The assembly of claim 1, wherein each flange segment includes 1 to 100 lugs.

4. The assembly of claim 1, further comprising means for rotationally or positionally coupling each flange segment.

5. The assembly of claim 4, wherein the means for rotationally or positionally coupling include at least one positioning stud formed on the corresponding segment and engaged in a complementary recess or orifice of the exhaust case or the cone, or vice versa.

6. The assembly of claim 4, wherein the means for rotationally or positionally coupling include at least one flat section formed on the corresponding segment and pressing on an edge or a corresponding planar surface of the exhaust case or the cone, or vice versa.

7. The assembly of claim 1, wherein the cone includes a radially inner skin and a radially outer skin defining a chamber between them, the outer skin at least partially forming the outer surface of the exhaust cone.

8. The assembly of claim 7, wherein the radially outer skin extends axially toward the upstream to the exhaust case, and wherein the flange segments are located radially inside the radially outer skin and the lugs are fastened to the radially inner skin.

9. The assembly of claim 1, wherein the upstream portion of each segment is fastened onto a radial or axial downstream portion of the exhaust case directly or via a connecting element.

10. A turbomachine including at least one assembly according to claim 1.

11. The assembly of claim 1, wherein each flange segment includes 1 to 10 lugs.

12. The assembly of claim 1, wherein each flange segment includes 3 to 6 lugs.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0046] FIG. 1 is a schematic axial sectional view of a turbomachine of the prior art,

[0047] FIG. 2 is a schematic axial sectional view of a propulsion assembly of the prior art,

[0048] FIG. 3 is an axial sectional half-view of a portion of a turbomachine exhaust assembly of the prior art,

[0049] FIG. 4 is a perspective view of a connecting flange between an exhaust cone and an exhaust case, according to the prior art,

[0050] FIG. 5 is a sectional view of a portion of an assembly according to the invention,

[0051] FIG. 6 is a sectional and perspective view of a portion of an assembly according to the invention,

[0052] FIG. 7 is a perspective view of a portion of an assembly according to the invention,

[0053] FIG. 8 is a perspective view of a flange segment according to an embodiment of the invention,

[0054] FIG. 9 is a perspective view of a flange segment according to another embodiment of the invention,

[0055] FIG. 10 is a schematic axial sectional view of a portion of a first embodiment of the assembly according to the invention,

[0056] FIG. 11 is a view corresponding to FIG. 10, illustrating a second embodiment of the invention,

[0057] FIG. 12 is a view corresponding to FIG. 10, illustrating a third embodiment of the invention,

[0058] FIG. 13 is an exploded perspective view, illustrating the case of a segment including a single lug, according to a first embodiment of the invention,

[0059] FIG. 14 is a perspective view, illustrating the case of a segment including a single lug, according to a first embodiment of the invention,

DETAILED DESCRIPTION OF THE INVENTION

[0060] FIGS. 5 to 8 illustrate an exhaust assembly for an aircraft turbomachine 1 according to an embodiment of the invention. This assembly includes an exhaust case 17 including, as above, a radially outer inner annular shell 19 and a radially outer annular shell 20, connected by radial blades. Only the inner shell 19 is illustrated in FIGS. 6 and 7.

[0061] The assembly further includes an exhaust cone 18 including a radially inner skin 29 and a radially outer skin 30, defining a chamber, for example an acoustic chamber 31, between them. The radially outer skin 30 is a so-called acoustic skin and extends axially toward the upstream to the inner shell 19 of the exhaust case 17. The upstream end 30a of the outer skin 30 is separated by an axial gap j at least equal to 0.2 mm, for example, in relation to the exhaust case 17.

[0062] An annular seal 32 extends between the downstream end of the inner shell 19 of the exhaust case 17 and the outer skin 30, so as to prevent the introduction of leakage air through the aforementioned gap j.

[0063] The downstream end of said inner shell 19 includes an axially extending annular rim 33, radially offset inward in relation to the radially outer surface 34 of the inner shell 17 intended to define the primary path 8.

[0064] A segmented annular flange 25 connects the annular rim 33 and the upstream end 29a of the inner skin 29 of the exhaust cone 18.

[0065] The flange 25 consists of several angular segments 25a arranged circumferentially end to end, each flange segment 25a including an upstream portion 35 extending circumferentially from which one or more planar lugs 28 extend in a rectilinear manner along an axis parallel with the axis X of the cone 18. The lugs 28 are regularly distributed along the circumference of the flange 25.

[0066] The upstream portion 35 of each segment 25a is fastened to the rim 33 via fastening means comprising for example one or more bolts 36, here 4 regularly bolts regularly distributed in the circumferential direction and illustrated in some cases schematically by axis lines.

[0067] The downstream end of each lug 28 is fastened to the upstream end 29a of the inner skin 29 of the cone 18 via fastening means comprising for example one or more bolts 37, here a single bolt, represented in some cases by axis lines. Obviously, fastening means by rivets or by welding are also possible for fastening the upstream portion 35 or lugs 28 of each segment 25a.

[0068] The number of lugs 28 per segment 25a is here equal to 4, each flange 25 including 8 segments.

[0069] Each lug 28 has a substantially constant thickness, a rectangular-shaped cross-section and a rectangular general shape, viewed radially from the outside inward.

[0070] The lugs 28 are sufficiently soft and flexible to be elastically deformable and make it possible to compensate the differential expansion effects between the cone 18 and the exhaust case 17. Indeed, the exhaust case 17 is for example made of metallic material, for example made of nickel-based alloy, for example of Inconel. The skins 29, 30 of the cone 18 are for example made of ceramic matrix composite material, the material differences giving rise to such differential expansions according to the temperature in operation.

[0071] FIG. 9 illustrates an embodiment where each segment 25a includes a single lug 28, the number of segments 25a of the flange 25 then being between 1 and 200. In this embodiment, the upstream portion 35 is fastened to the case 17 via at least two bolts 36. It will be noted that the presence of at least two bolts 36 for fastening the upstream portion 35 makes it possible to lock each segment 25a in rotation in relation to an axis perpendicular to the axis X of the exhaust case 17 and the cone 18, i.e., in relation to an axis or a radial direction.

[0072] FIG. 10 schematically illustrates the assembly of the flange 25 segments 25a in relation to the inner shell 19 of the case 17, on one hand, and in relation to the inner shell 29 of the cone 18, on the other.

[0073] FIG. 11 illustrates another embodiment, where the axial rim 33 is formed by an intermediate connecting element 38. This element 38 includes a radial annular portion 39, fastened by any suitable means to a radial annular portion 40 of the downstream end of the inner shell 19, and an axial or cylindrical annular portion, forming the rim 33 for fastening the upstream portion 35 of each segment 25a.

[0074] FIG. 12 further illustrates another embodiment wherein the upstream end 35 of each segment 25a includes a radial rim 39 extending radially outward, fastened to a radial annular portion 40 of the downstream end of the inner shell 19 of the exhaust case 17.

[0075] FIGS. 13 and 14 each illustrate an embodiment wherein each segment 25a includes a single lug 28.

[0076] In the embodiment in FIG. 13, the upstream portion 35 includes a hole 41 allowing the passage of a fastening means, for example a screw of a bolt 36, and a stud 42 engaged in an orifice or a recess 43 of complementary shape of the rim 33, the fastening means 36 being offset circumferentially from the stud 42. The fastening means 36, the orifice 42 and the recess 43 thus form means for preventing the rotation of the sector 25a in relation to an axis or a radial direction.

[0077] In the embodiment of FIG. 14, the upstream portion 35 includes two flat sections formed by studs 44 extending radially inward for example. The studs 44 are separated circumferentially from one another and are pressing on the downstream edge of the axial rim 33. The upstream portion 35 also includes fastening means, formed by one or more bolts 37 for example.