Gas turbine combustion chamber made of CMC and supported in a metal casing by CMC linking members
View Patent ↗The annular combustion chamber having ceramic matrix composite material walls is mounted inside a metal casing by linking members fastened to the chamber by brazing. The linking members comprise a plurality of inner linking tabs and a plurality of outer linking tabs connecting the chamber to the inner and outer metal shrouds of the casing, each linking tab has a first portion fastened to the outside surface of a wall of the combustion chamber by brazing, the first portions of the linking tabs being spaced apart from one another circumferentially so that the brazed connections between the chamber and the linking members occupy a set of limited zones that are spaced apart from one another.
1. A gas turbine having an annular combustion chamber with walls made of ceramic matrix composite material mounted inside a metal casing by linking members fastened to the chamber by brazing and connecting the chamber to inner and outer metal shrouds of the casing,
wherein the linking members comprise a plurality of inner linking tabs and a plurality of outer linking tabs which connect the combustion chamber to the inner and outer metal shrouds respectively, each linking tab having a first portion fastened to the outside surface of a wall of the combustion chamber by brazing, the first portions of said linking tabs being spaced apart from one another circumferentially so that the brazed connections between the chamber and the linking members are provided via a set of limited zones that are spaced apart from one another.
2. A gas turbine according to claim 1 , wherein the first portions of the inner linking tabs and of the outer linking tabs are integral with continuous inner and outer end ferrules respectively, defining bearing surfaces for annular sealing gaskets between the combustion chamber and a high pressure turbine nozzle situated immediately downstream from the chamber.
3. A gas turbine according to claim 2 , wherein the inner and outer end ferrules are made of ceramic matrix composite material and are made as a single piece together with the inner or outer linking tabs respectively.
4. A gas turbine according to claim 2 , wherein the inner and outer end ferrules are connected by brazing to the outside surfaces respectively of the inner and outer walls of the combustion chamber, the brazing being performed along continuous circumferential zones.
5. A gas turbine according to claim 1 , wherein perforations for bringing a flow of cooling air along the inside surfaces of the chamber wall are formed through the brazed-together zones of the linking members and the chamber walls.
6. A gas turbine according to claim 1 , wherein each linking tab of ceramic matrix composite material has a second end portion fastened to the metal casing.
7. A gas turbine according to claim 1 , wherein the inner and outer ceramic matrix composite material linking tabs are connected to the metal casing via respective inner and outer flexible metal linking parts.
8. A gas turbine according to claim 7 , wherein the inner and outer metal linking parts comprise inner and outer metal linking tabs each having a first end portion connected to a second end portion of a linking tab made of ceramic matrix composite material.
9. A gas turbine according to claim 8 , wherein the inner and outer metal linking tabs have second end portions integral with respective inner and outer metal ferrules fastened to the inner and outer metal shrouds.