FASTENING OF AN EXHAUST CONE IN A TURBOMACHINE TURBINE

Abstract

An assembly for a turbomachine with a longitudinal axis having an exhaust cone with an outer annular wall for the flow of a primary airflow and an annular box arranged radially inside the outer annular wall, an exhaust casing arranged upstream of and connected to the exhaust cone. One end of the outer annular wall or one end of the annular box may be free to move relative to and have no mechanical connection with the exhaust cone or the exhaust casing.

Claims

1. An assembly for a turbine of a turbomachine with a longitudinal axis, the assembly comprising: an exhaust cone comprising an outer annular wall for the flow of a primary airflow and an annular box arranged radially inside the outer annular wall; an exhaust casing arranged upstream of and connected to the exhaust cone, and wherein one end of the outer annular wall or one end of the annular box is free to move relative to and has no mechanical connection with the exhaust cone or the exhaust casing.

2. The assembly according to claim 1, wherein the annular box is connected on the one hand to the exhaust cone and on the other hand to the exhaust casing, and wherein the upstream end of the outer annular wall is free to move relative to the exhaust casing.

3. The assembly according to claim 1, wherein the outer annular wall of the exhaust cone is connected on the one hand to the exhaust cone and on the other hand to the exhaust casing, and wherein the upstream end of the annular box is free to move relative to the exhaust casing.

4. The assembly according to claim 1, wherein the outer annular wall of the exhaust cone is connected on the one hand to the exhaust cone and on the other hand to the exhaust casing, and wherein the downstream end of the annular box is free to move relative to the exhaust cone.

5. The assembly according to claim 1, wherein the annular box comprises an inner annular wall arranged concentric with the outer annular wall, and the upstream end of the annular box corresponds to the upstream end of the inner annular wall and the downstream end of the annular box corresponds to the downstream end of the inner annular wall.

6. The assembly according to claim 5, wherein the annular box comprises a plurality of partitions extending radially from the inner annular wall of the annular box and axially along the inner annular wall.

7. The assembly according to claim 5, comprising a connecting member fastened to the exhaust casing and connected to the outer annular wall of the exhaust cone and/or to the annular box.

8. The assembly according to claim 7, wherein the connecting member comprises first flexible fastening lugs distributed circumferentially around the longitudinal axis and second flexible fastening lugs distributed circumferentially around the longitudinal axis, wherein the first fastening lugs are connected to an upstream annular portion of the outer annular wall of the exhaust cone, and the second fastening lugs are connected to an upstream annular portion of the inner annular wall of the box.

9. The assembly according to claim 1, wherein the exhaust cone is made of a ceramic matrix composite material.

10. The assembly according to claim 1, wherein the acoustic box is made of a ceramic matrix composite material.

11. A turbine comprising an assembly according to claim 1.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0074] FIG. 1, already described, represents a schematic profile section of a turbomachine for an aircraft.

[0075] FIG. 2, already described, represents a schematic side view of a downstream portion of the turbomachine of FIG. 1.

[0076] FIG. 3 is a schematic representation of a side view of a first example of assembly of an exhaust cone to an exhaust casing.

[0077] FIG. 4 is a schematic representation of a side view of a variant of the first example of assembly of an exhaust cone to the exhaust casing. [FIG. 5] FIG. 5 is a schematic representation of a side view of a second example of assembly of an exhaust cone to an exhaust casing.

[0078] FIG. 6 is a schematic representation of a side view of a third example of assembly of an exhaust cone to an exhaust casing.

[0079] FIGS. 7a and 7b respectively represent a schematic perspective view of a first example of a connecting member and a schematic perspective view of an exhaust cone equipped with the first example of a connecting member.

[0080] FIGS. 8a, 8b and 8c respectively represent a schematic perspective view of the exhaust cone equipped with a second example of a connecting member, a schematic perspective view of the second example of a connecting member and a schematic side sectional view of the second connecting member.

[0081] FIGS. 9a and 9b represent a schematic side sectional view of a third example of a connecting member.

[0082] FIGS. 10a and 10b respectively represent a schematic partial perspective view of a fourth example of a connecting member and a schematic side sectional view of the fourth example of a connecting member.

[0083] FIGS. 11a and 11b respectively represent a schematic partial perspective view of a fifth example of a connecting member and a schematic side sectional view of the fifth example of a connecting member.

[0084] FIGS. 12a, 12b and 12c respectively represent a schematic side sectional view, a schematic front sectional view according to the axis AA and a schematic perspective view of a sixth example of a connecting member.

[0085] FIGS. 13a and 13b respectively represent a schematic front sectional view and a schematic perspective view of a seventh example of a connecting member.

[0086] FIGS. 14a and 14b respectively represent a schematic side sectional view and a schematic perspective view of an eighth example of a connecting member.

[0087] FIG. 15 represents a schematic perspective view of a ninth example of a connecting member.

[0088] FIGS. 16a and 16d represent schematic side sectional views of a tenth example of a connecting member and FIGS. 16b and 16c represent schematic perspective views of the tenth example of a connecting member.

[0089] FIGS. 17a and 17b represent schematic side sectional views of an eleventh example of a connecting member.

[0090] FIGS. 18a and 18b represent schematic side sectional views of a twelfth example of a connecting member.

[0091] FIGS. 19a and 19b represent schematic side sectional views of a thirteenth example of a connecting member and FIG. 19c represents a schematic perspective view of the thirteenth.

DETAILED DESCRIPTION OF THE INVENTION

[0092] Referring to FIG. 3, the exhaust cone 102 may be the exhaust cone 1 of the turbomachine 1 of FIG. 1 and comprises an outer annular wall 104 around a longitudinal axis X and forming a flow path of the primary flow at the outlet of a turbine arranged upstream of the exhaust cone 102. The exhaust cone 102 is made of a ceramic matrix composite material whereas the outer annular wall 104 is made of a ceramic matrix composite material.

[0093] An acoustic annular box 106 is further disposed in the exhaust cone 102 to absorb part of the noise generated by the turbomachine comprising the exhaust cone 102. The acoustic box 106 comprises an inner annular wall 108 arranged in the outer annular wall 104 of the exhaust cone 102. The acoustic box 106 also comprises a plurality of partitions 110 extending radially from the inner annular wall 108 of the acoustic box 106 and axially along the wall 108.

[0094] The inner annular wall 108 and/or the acoustic partitions are made of a ceramic matrix composite material or of a metallic material.

[0095] The inner annular wall 108 is fastened for example by screwing to the exhaust cone 102 and is connected to a shroud 112 of an exhaust casing 111 of the turbomachine. The shroud 112 of the exhaust casing 111 is arranged in the continuity of the outer annular wall 104 so as to define an upstream portion of the flow path of the primary flow coming out of the turbine.

[0096] The inner annular wall 108 is connected to the shroud 112 of the exhaust casing 111 via a connecting member 114.

[0097] The outer annular wall 104 is connected at its downstream end to the exhaust cone 102. The upstream end of the outer annular wall 104 has no mechanical connection and it is free to move, in particular in axial and radial movement, relative to the shroud 112, namely relative to the exhaust casing. The upstream end of the outer annular wall 104 is arranged in sliding contact with the shroud 112.

[0098] The outer annular wall 104 of the ejection cone 102 has an upstream end able to move axially and radially when the thermal expansions are significant. This allows limiting the impact of the differences in materials and/or thermal gradients between the acoustic box, the exhaust cone and the exhaust casing.

[0099] In the variant represented in FIG. 4, the outer annular wall 104 may also have an upstream end extending up to the exhaust casing 111. In this case, the shroud 112 is not necessary and the connecting member 114 is directly attached to the exhaust casing 111, in particular to a flange of the exhaust casing 111. Thus, the upstream end of the outer annular wall 104 is free of contact. The outer annular wall 104 then defines the upstream portion of the flow path of the primary flow coming out of the turbine.

[0100] In the variant represented in FIG. 5, the upstream end of the outer annular wall 104 is connected to the connecting member 114 whereas the upstream end of the inner annular wall 108 of the acoustic box 106 has no connection with said connecting member 114. The upstream end of the inner annular wall 108 of the acoustic box 106 is free to move, in particular in axial and radial movement, relative to the shroud 112, namely relative to the exhaust casing. The inner annular wall 108 of the acoustic box 106 has an upstream end able to move axially and radially when the thermal expansions are significant. This allows limiting the impact of the differences in materials and/or thermal gradients between the acoustic box, the exhaust cone and the exhaust casing.

[0101] In this variant, the exhaust cone 102 is connected to the exhaust casing 111 through the outer annular wall 104.

[0102] In the variant represented in FIG. 6, the upstream end of the outer annular wall 104 is connected to the connecting member 114 and the upstream end of the inner annular wall 108 of the acoustic box 106 is also connected to the connecting member 114. In turn, the downstream end of the inner annular wall 108 of the acoustic box 106 has no connection with the exhaust cone 102. The downstream end of the inner annular wall 108 of the acoustic box 106 is free to move, in particular in axial and radial movement, relative to the exhaust cone 102.

[0103] The inner annular wall 108 of the acoustic box 106 has a downstream end able to move axially and radially when the thermal expansions are significant. This allows limiting the impact of the differences in materials and/or thermal gradients between the acoustic box, the exhaust cone and the exhaust casing.

[0104] In this variant, the exhaust cone 102 is connected to the exhaust casing 111 via the outer annular wall 104.

[0105] While the present description has been made with reference to an acoustic annular box, it also applies to an annular box that is not necessarily acoustic.

[0106] FIG. 7 represents an upstream portion of a turbomachine turbine for example the turbomachine of FIG. 1. The turbomachine comprises a gas exhaust cone 102 comprising an outer annular wall 104 delimiting a flow path for a primary airflow coming out of the turbine. A shroud 106-1 is arranged upstream AM of the outer annular wall arranged in the continuity of an exhaust casing not represented in FIG. 7 and of an outer annular wall 104 of the exhaust cone 102 and delimiting an annular surface for the flow of the primary airflow coming out of the turbine. A box 106 is arranged in the exhaust cone 102 and is configured to absorb part of the noise generated by the turbomachine. The box 106 comprises an inner annular wall 108 arranged concentric with the outer annular wall 104 of the exhaust cone 102. The box 106 comprises partitions 110 extending radially from the inner annular wall 108 in the direction of the outer annular wall 104.

[0107] The outer annular wall 104 of the exhaust cone 102 is made of a ceramic matrix composite material or of metal. The box 106, in particular the inner annular wall 108 and the partitions 110 are made of a ceramic matrix composite material or of metal.

[0108] A connecting member 100 is intended to fasten the exhaust cone 102 and box 106 assembly to the exhaust casing. The connecting member 100 comprises a plurality of first fastening lugs 112-1 and second flexible fastening lugs 114-1 distributed circumferentially around the longitudinal axis X.

[0109] The connecting member comprises an annular flange 116 extending radially and comprising orifices to be fastened to the exhaust casing in particular to a corresponding flange of the exhaust casing.

[0110] A first end of each first fastening lug 112-1 is connected to a radially outer end of the annular flange 116 via an outer annular portion 113. A first end of each second fastening lug 114-1 is connected to a radially inner end of the annular flange 116 via an inner annular portion 115.

[0111] A second end of each first fastening lug 112-1 is connected, by screwing, to an upstream end 103 of the exhaust cone 102, in particular to an upstream end 103 of the outer annular wall 104 of the exhaust cone 102, and a second end of each second fastening lug 114-1 is connected, by screwing, to the inner annular wall 108 of the box 106.

[0112] The annular flange 116 is formed by a plurality of beams 117 distributed circumferentially around the longitudinal axis X and connecting the outer annular portion 113 and the inner annular portion 115. Alternatively, the annular flange may be solid and include holes to be assembled by screwing to the shroud 106-1 of the exhaust casing.

[0113] The second end of each first fastening lug 112-1 is arranged radially inward, namely in the direction of the longitudinal axis X with respect to the first end of said first fastening lug 112-1. The first fastening lugs ensure the connection of the exhaust cone 102 to the exhaust casing and the second fastening lugs ensure the connection of the box 106 to the exhaust casing. The first fastening lugs and the second fastening lugs are flexible and decoupled. Thus, they allow absorbing part of the thermodynamic stresses due to the difference in materials, on the one hand, between the exhaust cone and the exhaust casing and, on the other hand, between the box and the exhaust casing. The connecting lugs also allow absorbing part of the thermodynamic stresses undergone by the outer annular wall and the box because of their differential thermal expansions.

[0114] Referring to FIG. 8, the connecting member 200 comprises the same elements as the connecting member 100. In contrast, the annular flange 116 is formed integrally in one-piece. Each first fastening lug 112-1 is formed by a plate having a second end 202 connected to an upstream portion of the outer annular wall 104 located downstream of the upstream end 103 of the outer annular wall 104. Each first fastening lug 112-1 further comprises a first end 210 directly connected to the annular flange 116, in particular to the radially outer end 214 of the annular flange 116. Each first fastening lug 112-1 comprises a central portion 212 between the second end 202 and the first end 210. The second end 202 is arranged projecting radially outwards with respect to the first end 210. In addition, the second end 202 is longitudinally aligned with first end 210.

[0115] The second end 202 has a radial thickness smaller than the radial thickness of the central portion 212 and the radial thickness of the first end 210. This difference in radial thicknesses makes the first fastening lug 112-1 flexible.

[0116] Each second fastening lug 114-1 comprises a first end 208 connected to the annular flange 116 via the inner annular portion 115 which extends from the radially inner end 216 of the annular flange 116. Each second fastening lug 114-1 comprises a second end 204 connected by screwing to the inner annular wall 108 of the box 106. Each second fastening lug 114-1 comprises a central portion 206 between the second end 204 and the first end 208.

[0117] The central portion 206 has a radial thickness smaller than the radial thickness of the first end 208 and the radial thickness of the second end 204. This difference in radial thicknesses makes the second fastening lug 114-1 flexible.

[0118] The second end 204 of each second fastening lug 114-1 has a width in a circumferential direction smaller than a width in the circumferential direction of the first end 208 of the second fastening lug 114-1.

[0119] The outer annular wall 104 may extend upstream to ensure continuity with the exhaust casing instead of the shroud 106-1.

[0120] The number of first fastening lugs 112-1 may be less than the number of second fastening lugs 114-1. In this case, each first fastening lug 112-1 may be arranged circumferentially opposite one of the second fastening lugs 114-1.

[0121] Referring to FIG. 9, the connecting member 300 comprises the same elements as the connecting member 200 of FIG. 8. In contrast, each first fastening lug 112-1 is removable and is connected by screwing to the annular flange 116, in particular in a central portion of the connecting flange 116. Alternatively, each second fastening lug 114-1 is removable and is connected by screwing to the annular flange 116, in particular in a central portion of the connecting flange 116. In this case, each second fastening lug 114-1 has a uniform radial thickness at its first end 208, its second end 204 and its central portion 206.

[0122] Thus, the first fastening lugs 112-1 in the case of FIG. 9a or the second fastening lugs 114-1 in the case of FIG. 9b could be replaced more easily.

[0123] The upstream annular end 103 of the outer annular wall 104 of the exhaust cone 102 is arranged in continuity with an annular portion 304 of the exhaust casing to form a flow surface for the primary flow coming out of the turbine.

[0124] Referring to FIG. 10, the connecting member 400.sub.1 comprises the same elements as the connecting member 200 of FIG. 8. In contrast, the first fastening lugs 112-1 and the second fastening lugs 114-1 are connected to the radially outer end 214 of the annular flange 116. The first end 210 of each first fastening lug 112-1 extends from the outer annular portion 113 of the annular flange. The first end 210 of each second fastening lug 114-1 also extends from the outer annular portion 113 of the annular flange.

[0125] Each first fastening lug 112-1 is interposed with a second fastening lug 114-1. Each first fastening lug 112-1 is also spaced apart circumferentially from the second fastening lugs 114-1 arranged on either side of said first fastening lug 112-1.

[0126] A variant of the connecting member 400.sub.1 is shown in FIG. 16d, wherein each first fastening lug 112-1 is superimposed with a second fastening lug 114-1. The first end 210 of the first fastening lug 112-1 is screwed to the first end 208 of the second fastening lug superimposed with said first fastening lug 112-1 at the radially outer end 214 of the annular flange 116. Referring to FIG. 11, the connecting member 400.sub.2 comprises the same elements as the connecting member 400.sub.1 of FIG. 10. In contrast, the first fastening lugs 112-1 and the second fastening lugs 114-1 are connected to the radially inner end 216 of the annular flange 116. The first end 210 of each first fastening lug 112-1 extends from the inner annular portion 115 of the annular flange 116. The first end 210 of each second fastening lug 114-1 also extends from the outer annular portion 115 of the annular flange 116.

[0127] Each first fastening lug 112-1 is interposed with a second fastening lug 114-1. Each first fastening lug 112-1 is also spaced apart circumferentially from the second fastening lugs 114-1 arranged on either side of said first fastening lug 112-1.

[0128] A variant of the connecting member 400.sub.2 is represented in FIG. 16a, wherein each first fastening lug 112-1 is superimposed with a second fastening lug 114-1. The first end 210 of the first fastening lug 112-1 is screwed to the first end 208 of the second fastening lug 114-1 superimposed with said first fastening lug 112-1 at the radially inner end 216 of the annular flange 116.

[0129] Each first fastening lug 112-1 as represented in FIG. 16b, may be formed by a plate.

[0130] Each first fastening lug 112-1 as represented in FIG. 16c, may be formed by two fingers that are radially disjoint and connected at the first end 210 of the first fastening lug. The fingers have second ends 202.sub.2 and 202.sub.1 connected to the outer annular wall 104 of the exhaust cone 102.

[0131] Referring to FIG. 12, the connecting member 500 comprises the same elements as the connecting member 400. In contrast, each first fastening lug 112-1 extends in a first way of a circumferential direction B around the longitudinal axis X. The second end 202 of each first fastening lug 112-1 is arranged projecting radially with respect to the first end 210 of said first fastening lug 112-1. In addition, the second end 202 of each first fastening lug 112-1 is circumferentially offset with respect to the first end 210 of said first fastening lug 112-1.

[0132] In a variant represented in FIG. 13, the connecting member 500 further comprises at least one first fastening lug 112-1.sub.1 extending in the first way of the circumferential direction B and at least one first fastening lug 112-1.sub.2 extending in a second way opposite to the first way of the circumferential direction B. A pair of first fastening lugs 112-1.sub.1 and 112-1.sub.2 is arranged head-to-tail. A second end 210.sub.1 of the first fastening lug 112-1.sub.1 extending in the first way is adjacent to a second end 210.sub.2 of the first fastening lug 112-1.sub.2 extending in the second way. A first end 202.sub.1 of the first fastening lug 112-1.sub.1 extending in the first way is opposite to a first end 202.sub.2 of the first fastening lug 112-1.sub.2 extending in the second way.

[0133] The second end 210.sub.1 of the first fastening lug 112-1.sub.1 extending in the first way and the second end 210.sub.2 of the first fastening lug 112-1.sub.2 extending in the second way are connected to the same first end 208 of a second fastening lug 114-1.

[0134] Referring to FIG. 14, the connecting member 600 comprises the same elements as the connecting member 500 of FIG. 12. In contrast, each first fastening lug 112-1 extends simultaneously in the direction of the longitudinal axis X and in the first way of the circumferential direction B. The second end 202 of each first fastening lug 112-1 is circumferentially offset and in the direction of the longitudinal axis X with respect to the first end 210 of said first fastening lug 112-1.

[0135] The variant of the connecting member 600 represented in FIG. 15, comprises the same elements as the connecting member 500 of FIG. 13. In contrast and similarly to the connecting member 600 of FIG. 14, a first fastening lug 112-1.sub.1 extends simultaneously in the direction of the longitudinal axis X and in the first way of the circumferential direction B and is interposed with a first fastening lug 112-1.sub.2 extends simultaneously in the direction of the longitudinal axis X and in the second way of the circumferential direction B. The second end 202.sub.1 and 202.sub.2 of each first fastening lug 112-1.sub.1 and 112-1.sub.2 is circumferentially offset and in the direction of the longitudinal axis X with respect to the first end 210.sub.1 and 210.sub.2 of said first fastening lug 112-1.sub.1 and 112-1.sub.2.

[0136] Referring to FIG. 17, the connecting member 700 comprises the same elements as the connecting member 400.sub.2 of FIG. 16. In contrast, the first end 210 of each first fastening lug 112-1 is fastened by screwing to the second end 204 of a second fastening lug 114-1.

[0137] The second end 204 of each second fastening lug 114-1 is connected to the inner annular wall 108.

[0138] The second end 202 of each first fastening lug 112-1 is connected to the outer annular wall 104.

[0139] The first end 208 of each second fastening lug 114-1 is connected to the annular flange 116 at its radially inner end 216.

[0140] In FIG. 17a, the second end 202 of each first fastening lug 112-1 is arranged radially projecting outwards and downstream of the first end 210 of said first fastening lug 112-1.

[0141] In FIG. 17b, the second end 202 of each first fastening lug 112-1 is arranged radially projecting outwards and upstream of the first end 210 of said first fastening lug 112-1.

[0142] In a variant represented in FIGS. 19b and 19c, the first end 210 of each first fastening lug 112-1 is secured to the second end 204 of a second fastening lug 114-1, so that the first fastening lug 112-1 forms one piece with said second fastening lug 114-1.

[0143] Referring to FIG. 18, the connecting member 800 comprises the same elements as the connecting member 700 of FIG. 17. In contrast, the first end 208 of each second fastening lug 114-1 is fastened by screwing to the second end 202 of a first fastening lug 112-1.

[0144] The second end 210 of each second fastening lug 114-1 is connected to the inner annular wall 108.

[0145] The second end 202 of each first fastening lug 112-1 is connected to the outer annular wall 104.

[0146] The first end 210 of each first fastening lug 112-1 is connected to the annular flange 116 at its radially outer end 214.

[0147] In FIG. 18a, the second end 204 of each second fastening lug 114-1 is arranged projecting radially inward and downstream from the first end 208 of said second fastening lug 114-1.

[0148] In FIG. 18b, the second end 204 of each second fastening lug 114-1 is arranged projecting radially inward and upstream from the first end 208 of said second fastening lug 114-1.

[0149] In a variant represented in FIG. 19a, the first end 208 of each second fastening lug 114-1 is secured to the second end 202 of a first fastening lug 112-1, so that the first fastening lug 112-1 forms one piece with said second fastening lug 114-1.