TURBOMACHINE COMBUSTION CHAMBER

Abstract

A turbine engine includes a combustion chamber, comprising two coaxial axisymmetric walls extending one inside the other and delimiting between one another an annular air-circulation, an exterior wall, and at least one injector passing through the walls via ports, wherein the injector comprises a peripheral tube connected to the walls by three connections, at least two connections being of the slideway and/or ball-joint or bellows type.

Claims

1. A turbine engine having a combustion chamber, the combustion chamber comprising two coaxial axisymmetric walls extending one inside the other and delimiting therebetween an annular air-circulation space, and an exterior wall, and at least one injector crossing the walls via ports, wherein the injector comprises a peripheral tube that is connected to the walls by three connections, at least two connections being flexible sealed connections allowing for multidirectional clearance.

2. The turbine engine of claim 1, wherein just one of the three connections is formed by a sealed rigid assembly.

3. The turbine engine of claim 1, wherein the connection between the peripheral tube and an interior wall is formed by a linear annular connection having controlled leakage by way of a calibrated annular cross section.

4. The turbine engine of claim 1, wherein the connection between the peripheral tube and an intermediate wall is formed by a bellows.

5. The turbine engine of claim 1, wherein the connection between the peripheral tube and the exterior wall is formed by a bellows.

6. The turbine engine of claim 1, wherein the connection between the peripheral tube and an intermediate wall of a liner is formed by a ball-joint connection, and the connection between the peripheral tube and the exterior wall of the liner is formed by a sliding ball-joint connection.

7. The turbine engine of claim 1, wherein the connection between the peripheral tube and the exterior wall of a liner of the chamber is formed by a sliding ball-joint connection, and the connection between the peripheral tube and an intermediate wall of the liner is formed by a ball-joint connection.

8. The turbine engine of claim 1, wherein the connection between the peripheral tube and an intermediate wall of a liner is formed by a connection having several degrees of freedom to allow for axial displacement and tangential displacement of the tube, and a tolerance for a ball joint, and the connection between the peripheral tube and the exterior wall of the liner is formed by a sealed rigid assembly.

9. The turbine engine of claim 1, further comprising a gland, in which a head of the peripheral tube is inserted, passes through the exterior wall, the head having a discal flange engaged between the two parts of the gland.

10. The turbine engine of claim 1, wherein an inside end of the peripheral tube passes through a hole formed in the interior wall with clearance between the peripheral tube and the interior wall.

11. The turbine engine of claim 1, wherein the connection between the peripheral tube and the intermediate wall is achieved by a part having a conical upper portion that is flared towards the outside and is extended at the base thereof by a discal flange that is movable in radial translation in a slit formed in the head of a tubular extension soldered to a surface of the intermediate wall.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present disclosure will be more clearly understood on reading the following description of a non-limiting embodiment shown in the accompanying figures, in which:

[0030] FIG. 1 is a cross section of a turbine engine according to the present disclosure; and

[0031] FIGS. 2 to 8 are schematic views of different variants.

DETAILED DESCRIPTION

[0032] FIG. 1 is a perspective view of the turbine engine, comprising a heat exchanger (1), a compressor (2), a combustion chamber (3), and a turbine (4). A conical deflector (11), which is coaxial with the heat exchanger (1), causes the hot gases, originating from the turbine (4), to circulate towards a discharge outlet (12) after having passed through the heat exchanger (1), passing through two cassettes (5, 6) between the tubes.

[0033] The parts formed by the compressor (2), the combustion chamber (3) and the turbine (4) are known to a person skilled in the art, and are in accordance with the state of knowledge in the field of turbine engines.

[0034] The heat exchanger (1) is formed by a tube heat exchanger, comprising two coaxial annular cassettes (5, 6).

[0035] The external cassette (5) is formed by an assembly of parallel tubes, made of a metal alloy that is resistant to high temperatures, for example, refractory stainless steel 347.

[0036] By way of example, the external cassette (5) is formed of 2000 tubes having a length of 300 millimeters, an internal cross-section of 2.8 millimeters, and an external cross-section of 3 millimeters. The tubes are held in a known manner by means of inserts for defining the passages of hot gases originating from the turbine.

[0037] The tubes form a sleeve having an external radius of 158 millimeters and an internal radius of 128 millimeters.

[0038] The internal cassette (6) is formed of 2000 tubes having a length of 300 millimeters, an internal cross-section of 2.8 millimeters, and an external cross-section of 3 millimeters.

[0039] The tubes form a sleeve having an external radius of 123 millimeters and an internal radius of 67 millimeters.

[0040] The two cassettes (5, 6) are coaxial and are fitted into one another.

[0041] The two cassettes (5, 6) are united, at the end opposite the compressor (2), by an annular closure structure (8).

[0042] Each of the cassettes (5, 6) comprises, at each end, a front sealing plate that is pierced for the tubes to pass through, and ensures the constant center distance of the tubes. The tubes are brazed or soldered in order to ensure sealing in the region of the connection thereof to the front plates.

[0043] The closure structure (8) is formed of two coaxial parts that are fitted together and have the general shape of a rum baba mold, which parts are made of refractory stainless steel 347 of a thickness of 2 millimeters.

[0044] The outer part (9) has an external cross section that corresponds to the external cross section of the external cassette (5), and an internal cross section that corresponds to the internal cross section of the internal cassette (6).

[0045] The inner part (10) has an external cross section that corresponds to the internal cross section of the external cassette (5), and an internal cross section that corresponds to the external cross section of the internal cassette (6).

[0046] Each of the parts (9, 10) is rotationally symmetric according to the axis of the turbine engine, having a constant longitudinal cross section.

[0047] The closure structure (8) ensures the deflection of the gases, originating from the external cassette (5), towards the tubes that make up the internal cassette (6).

[0048] This solution ensures a double passage of the gases in the heat exchanger (1), which significantly increases the thermal efficiency thereof for a given bulk, and, in particular, length.

[0049] The combustion chamber (3) of the annular type has a double interior casing formed by a sheath (30) (“liner”) and an intermediate wall (31). The liner (30) and the intermediate wall (31) define a tubular volume for circulation of the air flow originating from the heat exchanger (1). An exterior wall (32) and the intermediate wall (31) define a tubular volume for circulation of the air flow originating from the compressor (2) and travelling towards the heat exchanger (1).

[0050] The tube (35) of the injector passes through the three walls (30 to 32) via three ports. The walls (30 to 32) as well as the tube (35) of the injector are subjected to longitudinal and radial expansions. The fixing is ensured by a combination of connections, avoiding the hyperstatic situations.

[0051] The connection between the tube (35) of the injector and the exterior wall (32) is ensured by a cylindrical bellows (36).

[0052] The connection between the tube (35) of the injector and the interior wall (30) is ensured by a sliding connection formed by a calibrated port defining, together with the outside surface of the tube (35), a calibrated annular clearance.

[0053] The connection between the tube (35) of the injector and the intermediate wall (31) is ensured by a fixed connection.

[0054] First Variant

[0055] The first variant is illustrated schematically by FIG. 2.

[0056] The tube (35) of the injector passes through the three walls (30 to 32) having the respective connections: [0057] a ball-joint connection (42) for passage through the exterior wall (32); [0058] a ball-joint sliding connection (41) for passage through the intermediate wall (31); and [0059] a free connection having calibrated peripheral clearance (40) for passage through the interior wall (30).

[0060] Second Variant

[0061] The second variant is illustrated schematically by FIG. 3.

[0062] The tube (35) of the injector passes through the three walls (30 to 32) having the respective connections: [0063] a ball-joint sliding connection (52) for passage through the exterior wall (32); [0064] a ball-joint connection (51) for passage through the intermediate wall (31); and [0065] a free connection having calibrated peripheral clearance (50) for passage through the interior wall (30).

[0066] Third Variant

[0067] The third variant is illustrated schematically by FIG. 4.

[0068] The tube (35) of the injector passes through the three walls (30 to 32) having the respective connections: [0069] a bellows (62) for passage through the exterior wall (32); [0070] a soldered connection (61) for passage through the intermediate wall (31); and [0071] a free connection having calibrated peripheral clearance (60) for passage through the interior wall (30).

[0072] Fourth Variant

[0073] The fourth variant is illustrated schematically by FIG. 5.

[0074] The tube (35) of the injector passes through the three walls (30 to 32) having the respective connections: [0075] a soldered connection (72) for passage through the exterior wall (32); [0076] a metal frustoconical bellows (71) for passage through the intermediate wall (31); and [0077] a free connection having calibrated peripheral clearance (70) for passage through the interior wall (30).

[0078] Fifth Variant

[0079] The fifth variant is illustrated schematically by FIGS. 6 to 8.

[0080] The tube (35) of the injector passes through the three walls (30 to 32) having the respective connections: [0081] a soldered connection (72) for passage through the exterior wall (32); [0082] a multidirectional connection (80) for passage through the intermediate wall (31); and [0083] a free connection having calibrated peripheral clearance (70) for passage through the interior wall (30).

[0084] The connection between the peripheral tube (35) and the intermediate wall (31) of the liner is formed by a connection (80) having several degrees of freedom for allowing axial displacement and tangential displacement of the tube, and a tolerance for a ball joint.

[0085] The connection between the peripheral tube (35) and the exterior wall (32) of the liner is formed by a sealed rigid assembly.

[0086] Referring to FIG. 8, a gland (37), in which the head (38) of the nozzle (35) is inserted, passes through the exterior wall (32). The head (38) comprises a discal flange (38) that is engaged between the two parts of the gland (37), which ensures clamping and sealing of the discal flange (38).

[0087] The inside end (40) passes through the interior wall (30), via passage in a simple hole formed in the interior wall (30). The hole is oblong in this case, in order to take into account the inclination of the axis of the nozzle (35) with respect to the radial axis.

[0088] The connection between the nozzle (35) and the intermediate wall (31) is achieved by a part having a conical upper portion (41) that is flared towards the outside and is extended at the base thereof by a discal flange (42) that is movable in radial translation in a slit (42) formed in the head (44) of a tubular extension (43) soldered to the surface of the interior wall (30).

[0089] The discal flange (42) is flexible, which furthermore allows for a lightweight ball joint with respect to the tubular extension (43).