Patent ID: 12253048

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIG.3, the exhaust cone102may be the exhaust cone1of the turbomachine1ofFIG.1and comprises an outer annular wall104around a longitudinal axis X and forming a flow path of the primary flow at the outlet of a turbine arranged upstream of the exhaust cone102. The exhaust cone102is made of a ceramic matrix composite material whereas the outer annular wall104is made of a ceramic matrix composite material.

An acoustic annular box106is further disposed in the exhaust cone102to absorb part of the noise generated by the turbomachine comprising the exhaust cone102. The acoustic box106comprises an inner annular wall108arranged in the outer annular wall104of the exhaust cone102. The acoustic box106also comprises a plurality of partitions110extending radially from the inner annular wall108of the acoustic box106and axially along the wall108.

The inner annular wall108and/or the acoustic partitions are made of a ceramic matrix composite material or of a metallic material.

The inner annular wall108is fastened for example by screwing to the exhaust cone102and is connected to a shroud112of an exhaust casing111of the turbomachine. The shroud112of the exhaust casing111is arranged in the continuity of the outer annular wall104so as to define an upstream portion of the flow path of the primary flow coming out of the turbine.

The inner annular wall108is connected to the shroud112of the exhaust casing111via a connecting member114.

The outer annular wall104is connected at its downstream end to the exhaust cone102. The upstream end of the outer annular wall104has no mechanical connection and it is free to move, in particular in axial and radial movement, relative to the shroud112, namely relative to the exhaust casing. The upstream end of the outer annular wall104is arranged in sliding contact with the shroud112.

The outer annular wall104of the ejection cone102has 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.

In the variant represented inFIG.4, the outer annular wall104may also have an upstream end extending up to the exhaust casing111. In this case, the shroud112is not necessary and the connecting member114is directly attached to the exhaust casing111, in particular to a flange of the exhaust casing111. Thus, the upstream end of the outer annular wall104is free of contact. The outer annular wall104then defines the upstream portion of the flow path of the primary flow coming out of the turbine.

In the variant represented inFIG.5, the upstream end of the outer annular wall104is connected to the connecting member114whereas the upstream end of the inner annular wall108of the acoustic box106has no connection with said connecting member114. The upstream end of the inner annular wall108of the acoustic box106is free to move, in particular in axial and radial movement, relative to the shroud112, namely relative to the exhaust casing. The inner annular wall108of the acoustic box106has 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.

In this variant, the exhaust cone102is connected to the exhaust casing111through the outer annular wall104.

In the variant represented inFIG.6, the upstream end of the outer annular wall104is connected to the connecting member114and the upstream end of the inner annular wall108of the acoustic box106is also connected to the connecting member114. In turn, the downstream end of the inner annular wall108of the acoustic box106has no connection with the exhaust cone102. The downstream end of the inner annular wall108of the acoustic box106is free to move, in particular in axial and radial movement, relative to the exhaust cone102.

The inner annular wall108of the acoustic box106has 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.

In this variant, the exhaust cone102is connected to the exhaust casing111via the outer annular wall104.

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.

FIG.7represents an upstream portion of a turbomachine turbine for example the turbomachine ofFIG.1. The turbomachine comprises a gas exhaust cone102comprising an outer annular wall104delimiting a flow path for a primary airflow coming out of the turbine. A shroud106-1is arranged upstream AM of the outer annular wall arranged in the continuity of an exhaust casing not represented inFIG.7and of an outer annular wall104of the exhaust cone102and delimiting an annular surface for the flow of the primary airflow coming out of the turbine. A box106is arranged in the exhaust cone102and is configured to absorb part of the noise generated by the turbomachine. The box106comprises an inner annular wall108arranged concentric with the outer annular wall104of the exhaust cone102. The box106comprises partitions110extending radially from the inner annular wall108in the direction of the outer annular wall104.

The outer annular wall104of the exhaust cone102is made of a ceramic matrix composite material or of metal. The box106, in particular the inner annular wall108and the partitions110are made of a ceramic matrix composite material or of metal.

A connecting member100is intended to fasten the exhaust cone102and box106assembly to the exhaust casing. The connecting member100comprises a plurality of first fastening lugs112-1and second flexible fastening lugs114-1distributed circumferentially around the longitudinal axis X.

The connecting member comprises an annular flange116extending radially and comprising orifices to be fastened to the exhaust casing in particular to a corresponding flange of the exhaust casing.

A first end of each first fastening lug112-1is connected to a radially outer end of the annular flange116via an outer annular portion113. A first end of each second fastening lug114-1is connected to a radially inner end of the annular flange116via an inner annular portion115.

A second end of each first fastening lug112-1is connected, by screwing, to an upstream end103of the exhaust cone102, in particular to an upstream end103of the outer annular wall104of the exhaust cone102, and a second end of each second fastening lug114-1is connected, by screwing, to the inner annular wall108of the box106.

The annular flange116is formed by a plurality of beams117distributed circumferentially around the longitudinal axis X and connecting the outer annular portion113and the inner annular portion115. Alternatively, the annular flange may be solid and include holes to be assembled by screwing to the shroud106-1of the exhaust casing.

The second end of each first fastening lug112-1is arranged radially inward, namely in the direction of the longitudinal axis X with respect to the first end of said first fastening lug112-1. The first fastening lugs ensure the connection of the exhaust cone102to the exhaust casing and the second fastening lugs ensure the connection of the box106to 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.

Referring toFIG.8, the connecting member200comprises the same elements as the connecting member100. In contrast, the annular flange116is formed integrally in one-piece. Each first fastening lug112-1is formed by a plate having a second end202connected to an upstream portion of the outer annular wall104located downstream of the upstream end103of the outer annular wall104. Each first fastening lug112-1further comprises a first end210directly connected to the annular flange116, in particular to the radially outer end214of the annular flange116. Each first fastening lug112-1comprises a central portion212between the second end202and the first end210. The second end202is arranged projecting radially outwards with respect to the first end210. In addition, the second end202is longitudinally aligned with first end210.

The second end202has a radial thickness smaller than the radial thickness of the central portion212and the radial thickness of the first end210. This difference in radial thicknesses makes the first fastening lug112-1flexible.

Each second fastening lug114-1comprises a first end208connected to the annular flange116via the inner annular portion115which extends from the radially inner end216of the annular flange116. Each second fastening lug114-1comprises a second end204connected by screwing to the inner annular wall108of the box106. Each second fastening lug114-1comprises a central portion206between the second end204and the first end208.

The central portion206has a radial thickness smaller than the radial thickness of the first end208and the radial thickness of the second end204. This difference in radial thicknesses makes the second fastening lug114-1flexible.

The second end204of each second fastening lug114-1has a width in a circumferential direction smaller than a width in the circumferential direction of the first end208of the second fastening lug114-1.

The outer annular wall104may extend upstream to ensure continuity with the exhaust casing instead of the shroud106-1.

The number of first fastening lugs112-1may be less than the number of second fastening lugs114-1. In this case, each first fastening lug112-1may be arranged circumferentially opposite one of the second fastening lugs114-1.

Referring toFIG.9, the connecting member300comprises the same elements as the connecting member200ofFIG.8. In contrast, each first fastening lug112-1is removable and is connected by screwing to the annular flange116, in particular in a central portion of the connecting flange116. Alternatively, each second fastening lug114-1is removable and is connected by screwing to the annular flange116, in particular in a central portion of the connecting flange116. In this case, each second fastening lug114-1has a uniform radial thickness at its first end208, its second end204and its central portion206.

Thus, the first fastening lugs112-1in the case ofFIG.9aor the second fastening lugs114-1in the case ofFIG.9bcould be replaced more easily.

The upstream annular end103of the outer annular wall104of the exhaust cone102is arranged in continuity with an annular portion304of the exhaust casing to form a flow surface for the primary flow coming out of the turbine.

Referring toFIG.10, the connecting member4001comprises the same elements as the connecting member200ofFIG.8. In contrast, the first fastening lugs112-1and the second fastening lugs114-1are connected to the radially outer end214of the annular flange116. The first end210of each first fastening lug112-1extends from the outer annular portion113of the annular flange. The first end210of each second fastening lug114-1also extends from the outer annular portion113of the annular flange.

Each first fastening lug112-1is interposed with a second fastening lug114-1. Each first fastening lug112-1is also spaced apart circumferentially from the second fastening lugs114-1arranged on either side of said first fastening lug112-1.

A variant of the connecting member4001is shown inFIG.16d, wherein each first fastening lug112-1is superimposed with a second fastening lug114-1. The first end210of the first fastening lug112-1is screwed to the first end208of the second fastening lug superimposed with said first fastening lug112-1at the radially outer end214of the annular flange116. Referring toFIG.11, the connecting member4002comprises the same elements as the connecting member4001ofFIG.10. In contrast, the first fastening lugs112-1and the second fastening lugs114-1are connected to the radially inner end216of the annular flange116. The first end210of each first fastening lug112-1extends from the inner annular portion115of the annular flange116. The first end210of each second fastening lug114-1also extends from the outer annular portion115of the annular flange116.

Each first fastening lug112-1is interposed with a second fastening lug114-1. Each first fastening lug112-1is also spaced apart circumferentially from the second fastening lugs114-1arranged on either side of said first fastening lug112-1.

A variant of the connecting member4002is represented inFIG.16a, wherein each first fastening lug112-1is superimposed with a second fastening lug114-1. The first end210of the first fastening lug112-1is screwed to the first end208of the second fastening lug114-1superimposed with said first fastening lug112-1at the radially inner end216of the annular flange116.

Each first fastening lug112-1as represented inFIG.16b, may be formed by a plate.

Each first fastening lug112-1as represented inFIG.16c, may be formed by two fingers that are radially disjoint and connected at the first end210of the first fastening lug. The fingers have second ends2022and2021connected to the outer annular wall104of the exhaust cone102.

Referring toFIG.12, the connecting member500comprises the same elements as the connecting member400. In contrast, each first fastening lug112-1extends in a first way of a circumferential direction B around the longitudinal axis X. The second end202of each first fastening lug112-1is arranged projecting radially with respect to the first end210of said first fastening lug112-1. In addition, the second end202of each first fastening lug112-1is circumferentially offset with respect to the first end210of said first fastening lug112-1.

In a variant represented inFIG.13, the connecting member500further comprises at least one first fastening lug112-11extending in the first way of the circumferential direction B and at least one first fastening lug112-12extending in a second way opposite to the first way of the circumferential direction B. A pair of first fastening lugs112-11and112-12is arranged head-to-tail. A second end2101of the first fastening lug112-11extending in the first way is adjacent to a second end2102of the first fastening lug112-12extending in the second way. A first end2021of the first fastening lug112-11extending in the first way is opposite to a first end2022of the first fastening lug112-12extending in the second way.

The second end2101of the first fastening lug112-11extending in the first way and the second end2102of the first fastening lug112-12extending in the second way are connected to the same first end208of a second fastening lug114-1.

Referring toFIG.14, the connecting member600comprises the same elements as the connecting member500ofFIG.12. In contrast, each first fastening lug112-1extends simultaneously in the direction of the longitudinal axis X and in the first way of the circumferential direction B. The second end202of each first fastening lug112-1is circumferentially offset and in the direction of the longitudinal axis X with respect to the first end210of said first fastening lug112-1.

The variant of the connecting member600represented inFIG.15, comprises the same elements as the connecting member500ofFIG.13. In contrast and similarly to the connecting member600ofFIG.14, a first fastening lug112-11extends 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 lug112-12extends simultaneously in the direction of the longitudinal axis X and in the second way of the circumferential direction B. The second end2021and2022of each first fastening lug112-11and112-12is circumferentially offset and in the direction of the longitudinal axis X with respect to the first end2101and2102of said first fastening lug112-11and112-12.

Referring toFIG.17, the connecting member700comprises the same elements as the connecting member4002ofFIG.16. In contrast, the first end210of each first fastening lug112-1is fastened by screwing to the second end204of a second fastening lug114-1.

The second end204of each second fastening lug114-1is connected to the inner annular wall108.

The second end202of each first fastening lug112-1is connected to the outer annular wall104.

The first end208of each second fastening lug114-1is connected to the annular flange116at its radially inner end216.

InFIG.17a, the second end202of each first fastening lug112-1is arranged radially projecting outwards and downstream of the first end210of said first fastening lug112-1.

InFIG.17b, the second end202of each first fastening lug112-1is arranged radially projecting outwards and upstream of the first end210of said first fastening lug112-1.

In a variant represented inFIGS.19band19c, the first end210of each first fastening lug112-1is secured to the second end204of a second fastening lug114-1, so that the first fastening lug112-1forms one piece with said second fastening lug114-1.

Referring toFIG.18, the connecting member800comprises the same elements as the connecting member700ofFIG.17. In contrast, the first end208of each second fastening lug114-1is fastened by screwing to the second end202of a first fastening lug112-1.

The second end210of each second fastening lug114-1is connected to the inner annular wall108.

The second end202of each first fastening lug112-1is connected to the outer annular wall104.

The first end210of each first fastening lug112-1is connected to the annular flange116at its radially outer end214.

InFIG.18a, the second end204of each second fastening lug114-1is arranged projecting radially inward and downstream from the first end208of said second fastening lug114-1.

InFIG.18b, the second end204of each second fastening lug114-1is arranged projecting radially inward and upstream from the first end208of said second fastening lug114-1.

In a variant represented inFIG.19a, the first end208of each second fastening lug114-1is secured to the second end202of a first fastening lug112-1, so that the first fastening lug112-1forms one piece with said second fastening lug114-1.