RU2773412C1 - Combustion chamber for turbomachine - Google Patents

Abstract

FIELD: turbomachine combustion chambers.

SUBSTANCE: invention relates to a combustion chamber for a turbomachine such as an aircraft turbojet or an aircraft turboprop. The combustion chamber (1) of the turbomachine contains a bottom wall (4) containing at least one hole (5), at least one sleeve (12) installed upstream from the bottom wall (4) and attached to the bottom wall (4), closing the ring (13), limiting the annular groove (11) together with the sleeve (12) and attached to the sleeve (12), at least one air-fuel mixture injection system (6), having an axis (A) and installed in the hole (5) of the bottom wall (4), while the injection system (6) contains an annular collar (10) extending radially relative to the specified axis (A) and installed in the specified groove (11) with a radial clearance, the deflector (14), located downstream from the bottom wall (4), attached to the sleeve (12) and/or to the bottom wall (4) and containing a radially inner part located in the axial direction between the bottom wall (4) and the downstream end of the injection system (6). The injection system (6) contains at least one protruding part configured to enter the hollow part (16) of the deflector (14), or vice versa, in the first angular position of the installation of the injection system (6) relative to the deflector (14), wherein in the second angular position, the said protruding part is configured to come in the axial direction to the stop position against the radial surface or the downstream surface of the deflector (14) or, respectively, the injection system (4) to hold the injection system (6) relative to the deflector (14 ), while the specified protruding part is offset in the angular direction from the hollow part (16) in the specified second position.

EFFECT: invention improves operational reliability.

10 cl, 8 dwg

Description

Technical field

The invention relates to a combustion chamber for a turbomachine such as an aircraft turbojet or an aircraft turboprop.

Prior Art

In FIG. 1 shows part of an annular combustion chamber 1 of a turbomachine, such as an aircraft turbojet or an aircraft turboprop, in accordance with the prior art.

The combustion chamber 1 is located at the outlet of a diffuser (not shown), which, in turn, is at the outlet of the compressor. The chamber 1 comprises an inner wall 2 of rotation and an outer wall 3 of rotation connected upstream to the annular bottom wall 4 of the chamber.

The bottom wall 4 of the chamber contains openings 5, in which systems 6 for injecting an air-fuel mixture into the chamber 1 are installed, while the air enters from the diffuser, and the fuel is supplied through nozzles (not shown) evenly distributed along the periphery of the combustion chamber 1. Each nozzle contains a fuel injection head aligned with the axis A of the corresponding hole 5.

Part of the air flow created by the compressor and leaving the diffuser feeds the inner and outer annular channels passing around the combustion chamber. Another part of the air flow passes into the injection systems and mixes with the fuel entering through the nozzles, after which it is sprayed into the combustion chamber 1.

For each injection system 6, the central fuel injector is surrounded by an annular wall 7 of said injection system 6 forming a Venturi tube. Cup 8 surrounds the annular wall, said cup 8 expanding downstream. The injection system usually contains ribs 9 designed to communicate the air flow passing through it in a circular motion, contributing to the homogenization of the fuel-air mixture.

The radially outer periphery of the bowl contains a radial collar 10 movably mounted in a radial groove 11, limited by a bushing 12 fixed by welding on the bottom wall 4 of the combustion chamber 1, and a closing ring 13 welded to the bushing 12.

The radial movement of the shoulder 10 in the groove 11 makes it possible to compensate for the relative movements between the injectors and the turbomachine housing to which they are attached, on the one hand, and the combustion chamber 1, on the other hand. Such movements occur during operation due to differential expansions between the various elements of the turbomachine.

In addition, a deflector 14 is installed downstream from the bottom wall 4, while the deflector 14 contains a cylindrical part 15 installed inside the cylindrical part 16 of the sleeve 12 and fixed by soldering or welding on the specified cylindrical part 16 of the sleeve 12.

There is a risk of deflector 14 detaching from sleeve 12, which could result in damage to downstream components, in particular the turbine.

The invention aims to prevent such damage in a simple, reliable and inexpensive manner.

Disclosure of invention

For this, the object of the invention is a combustion chamber of a turbomachine containing:

- a bottom wall containing at least one opening,

- at least one sleeve installed upstream of the bottom wall and attached to the bottom wall,

- a closing ring, which, together with the sleeve, defines the annular groove and is attached to the sleeve,

- at least one air-fuel mixture injection system, having an axis and installed in the hole of the bottom wall, while the injection system contains an annular collar extending radially with respect to the specified axis and installed in the specified groove with a radial clearance,

- a deflector located downstream of the bottom wall, attached to the sleeve and / or to the bottom wall, containing a radially inner part located in the axial direction between the bottom wall and the downstream end of the injection system,

moreover, the injection system contains at least one protruding part configured to enter the hollow part of the deflector, or vice versa, in the first angular position of the installation of the injection system relative to the deflector, and in the second angular position, the specified protruding part is configured to come in the axial direction to the position abutting against the radial surface or the downstream surface of the baffle or, respectively, the injection system for holding the injection system relative to the baffle, while said protruding part is angularly offset from the hollow part in said second position.

Thus, the baffle and the injection system comprise a bayonet-type system for mounting the injection system in the baffle at a first angular position and holding the baffle axially relative to the injection system at a second angular position. By separating the deflector on the one hand and the sleeve and/or bottom wall on the other hand, the deflector still remains in place, held axially by the projection, so that there is no risk of damage to downstream turbomachine components.

The terms "downstream" and "upstream" are defined with respect to the gas flow passing through the turbomachine.

The concepts of "radial", "axial" and "circumferential" are defined relative to the axis of the injection system.

The combustion chamber may include position holding means configured to hold the injection system in its second position relative to the baffle.

The protruding part may extend radially from the downstream end of the injection system, while the hollow part is formed in the baffle.

For example, the protruding part is made in the form of a protrusion or tab extending radially outward. The hollow part can be made, for example, in the form of a groove or recess in the deflector.

The number of projecting parts and hollow parts is, for example, three. The protruding and hollow parts can be evenly distributed around the circumference.

The injection system may include a rotation locking tab held or locked from rotation by circumferential stops of the sleeve and/or the closing ring.

The sleeve may comprise a first circumferential stop and a second circumferential stop, wherein the rotation locking tab is configured to rest on the first circumferential stop at a first angular position of the injection system, and the rotation lock tab is configured to rest on the second circumferential stop during the second angular position of the injection system.

Thus, the circumferential stops form end stops that provide and limit the angular displacement of the injection system relative to the deflector. This design facilitates the installation of the entire assembly.

The closure ring may include a third circumferential stop, wherein the tab is configured to be held in position between the second and third circumferential stops to hold the injection system in its second angular position.

Thus, the second and third circumferential stops form the aforementioned position holding means together with the position holding tab.

The bushing may include a radially inner cylindrical part installed in the opening of the bottom wall and attached to the periphery of the said opening.

Appropriate fastening is provided, for example, by soldering or welding.

The deflector may include a cylindrical part installed in the radially inner cylindrical part of the sleeve and attached to said radially inner cylindrical part.

Appropriate fastening is provided, for example, by soldering or welding.

The bushing may comprise a radially outer cylindrical portion located axially upstream of the radially inner cylindrical portion, with the closure ring mounted radially within the radially outer cylindrical portion.

The combustion chamber may include a nozzle having an injection head installed in the injection system, while the injection system contains air supply means and means for obtaining a mixture of air with fuel coming from the nozzle.

The object of the invention is also a turbomachine containing a combustion chamber of the type mentioned above.

In addition, the subject of the invention is also a method for assembling a combustion chamber of the above type, which includes the following steps, in which:

- the sleeve and the deflector are attached to the bottom wall,

- the injection system is placed in the first angular position and is inserted into the opening of the bottom wall through the sleeve and the deflector by translational movement along the axis of the injection system and the specified opening, while the protruding part passes through the hollow part,

- the injection system is rotated to its second angular position so that the protruding part forms an axial stop with a deflector,

- install the closing ring so as to hold in the axial direction the annular shoulder of the injection system in the groove defined by the closing ring and the sleeve, and to lock the injection system from rotation.

Brief description of the drawings

In FIG. 1 shows part of a known combustion chamber, sectional view;

in fig. 2 is a view corresponding to FIG. 1 explaining a combustion chamber according to an embodiment of the invention;

in fig. 3 - injection system, perspective view;

in fig. 4 - injection system, perspective view;

in fig. 5 - deflector, perspective view;

in fig. 6 is a part of the combustion chamber according to the invention, with the injection system in its second angular position relative to the deflector, perspective view;

in fig. 7 - bushing, chamber bottom and injection system in the second angular position of the injection system, perspective view;

in fig. 8 is a view corresponding to FIG. 7, which has a closure ring added.

Embodiments of the invention

In FIG. 2-8 show a portion of a combustion chamber 1 according to an embodiment of the invention for equipping a turbomachine such as an aircraft turbojet or an aircraft turboprop.

The chamber 1 comprises an inner wall 2 of rotation and an outer wall 3 of rotation connected upstream to the annular bottom wall 4 of the chamber.

The bottom wall 4 of the chamber contains openings 5, in which systems 6 for injecting an air-fuel mixture into the chamber 1 are installed, while the air enters from the diffuser, and the fuel is supplied through nozzles (not shown) evenly distributed along the periphery of the combustion chamber 1. Each nozzle contains a fuel injection head aligned with the axis A of the corresponding hole 5.

Part of the air flow created by the compressor and leaving the diffuser feeds the inner and outer annular channels passing around the combustion chamber. Another part of the air flow passes into the injection systems and mixes with the fuel entering through the nozzles, after which it is sprayed into the combustion chamber 1.

For each injection system 6, the central fuel injector is surrounded by an annular wall 7 of said injection system 6 forming a Venturi tube. Cup 8 surrounds the annular wall, said cup 8 expanding downstream.

The downstream end of the bowl 8 includes an annular collar 17 extending radially outward. As shown more clearly in FIG. 3 and 4, protrusions or tabs 18 extend radially outward from the radially outer periphery of the annular bead 17. In this case, the protrusions are made in the amount of three and are evenly distributed around the circumference, that is, offset in the angular direction relative to each other by an angle of 120°.

In general, the injection system 6 also includes fins 9 for imparting a circular motion to the airflow entering through the channel delimited between the cup 8 and the annular wall, helping to homogenize the air-fuel mixture.

The radially outer periphery of the bowl contains a radial bead 10 connected to the bead 17 by a cylindrical part 19. The bead 10 is located axially upstream of the bead 17. The bead 10 is movably mounted in a radial groove 11 bounded by a sleeve 12 welded to the bottom wall 4 of the chamber 1 combustion, and a closing ring 13 welded to the sleeve 12. The shoulder 10 includes a tab 10a extending radially outward from the radially outer edge of the shoulder 10.

The radial movement of the bead 10 in the groove 11 makes it possible to compensate for the relative movements between the injectors and the turbomachine housing on which they are fixed, on the one hand, and the combustion chamber 1, on the other hand. Such movements occur during operation as a result of differential expansions between the various elements of the turbomachine.

In particular, from the upstream side to the downstream side, the sleeve 12 comprises a cylindrical part 20, a radially extending annular part 21, and a cylindrical part 16. The cylindrical part 20 has a larger diameter than the cylindrical part 16. The cylindrical part 16 is installed in the hole 5 of the bottom wall and attached to said bottom wall 4 by soldering or welding. The radially inner region of the radial part 21 comprises a downstream support surface which rests on the bottom wall 4.

The cylindrical part 20 extends only on part of the circumference. In particular, the sleeve comprises an angular sector having no cylindrical portion 20 as shown in FIG. 7 and this angular sector extends through 120°. The circumferential ends 20a, 20b of the cylindrical part 20 are configured to form stops for the tab 10a, which is placed in the specified angular sector that does not have a cylindrical part 20.

Closing ring 13 has a generally T-shaped cross-section and includes an annular radial part 22 and a cylindrical part 23. closing ring 23 are spaced from each other in the axial direction and limit the groove 11 between them.

The downstream end of the cylindrical portion 23 contains a recess 23a (FIG. 8), the function of which will be described later.

In addition, a deflector 14 is installed downstream of the bottom wall 4.

From the upstream side to the downstream side, the deflector 14 comprises a cylindrical portion 15, a radial portion 24 shaped like a sector of an annulus, and collars 25 extending axially downstream on the radially inner and outer edges of the radial portion 24. Cylindrical portion 15 installed inside the cylindrical part 16 of the sleeve 12 and attached by soldering or welding to the specified cylindrical part 16.

In addition, the cylindrical part 16 contains grooves 26, in this case three in number, evenly distributed around the circumference.

The installation of such a combustion chamber is carried out as follows.

First, the sleeve 12, in particular the cylindrical part 16 is installed in the hole 5 of the bottom wall 4. The deflector 14, in particular the cylindrical part 15 is installed in the cylindrical part 16 of the sleeve. The cylindrical part 16, the cylindrical part 15 and the bottom wall are interconnected by soldering or welding.

Then, in the hole 5 of the bottom wall, through the sleeve 12 and the deflector 14, an injection system is installed. In particular, the injection system is placed in the first angular position so that the protrusions 18 of the injection system 6 are opposite the grooves 26 of the deflector 14. The injection system is then translated in a downstream direction until the shoulder 10 rests on the radial part 21 of the sleeve. In this case, the protrusions 18 are immediately downstream of the radial part 24 of the deflector, and the tab 10a is placed in the region of the sleeve 12, which does not have a cylindrical shoulder 20.

Thereafter, the injection system 16 is rotated to the second angular position shown in FIG. 6-8. In particular, the injection system is rotated through an angle of 60° between the first and second angular positions, this angle corresponding to half the angular spacing between two grooves 26 or between two projections 18.

In the second angular position, the lug 10a of the injection system 6 rests on the circumferential stop 20a, which facilitates installation.

In the second angular position, the protrusions 18 are displaced from the grooves 26 and can come to rest on the radial portion 24 of the deflector 14 to prevent axial movement of the injection system 6 .

In the cylindrical part 20 of the sleeve 10, the closing ring 13 is installed so that the tab 10a is inserted and held in position in the recess 23a. The closing ring 13 is then attached by soldering or welding to the sleeve 12. Thus, rotation of the injection system 6 is prevented.

This design allows easy installation of the assembly and prevents the outlet of the deflector 14 in case of failure of the weld or soldering of the cylindrical part 15. This avoids damage to parts of the turbomachine that are downstream of the bottom wall 4 or the combustion chamber 1.

Claims (20)

1. The combustion chamber (1) of a turbomachine, containing: - a bottom wall (4) containing at least one opening (5), - at least one sleeve (12) installed upstream of the bottom wall (4) and attached to the bottom wall (4), - a closing ring (13), which, together with the sleeve (12), limits the annular groove (11) and is attached to the sleeve (12), - at least one air-fuel mixture injection system (6), having an axis (A) and installed in the hole (5) of the bottom wall (4), while the injection system (6) contains an annular collar (10) extending radially relative to the specified axis (A) and installed in the specified groove (11) with a radial clearance, - a deflector (14) located downstream from the bottom wall (4), attached to the sleeve (12) and/or to the bottom wall (4) and containing a radially inner part located in the axial direction between the bottom wall (4) and the bottom downstream end of injection system (6), characterized in that the injection system (6) contains at least one protruding part (18) configured to enter the hollow part (16) of the deflector (14), or vice versa, in the first angular position of the installation of the injection system (6) relative to the deflector (14), moreover, in the second angular position, said protruding part (18) is configured to come in the axial direction to the stop position against the radial surface or the downstream surface of the deflector (14) or, respectively, the injection system (4) to hold the system ( 6) injection relative to the deflector (14), while the specified protruding part (18) is offset in the angular direction from the hollow part (16) in the specified second position. 2. The combustion chamber (1) according to claim 1, characterized in that it contains means (10a, 23a) for holding in position, configured to hold the injection system (6) in its second position relative to the deflector (14). 3. The combustion chamber (1) according to claim 1, characterized in that the protruding part (18) extends radially from the downstream end of the injection system (6), while the hollow part (16) is made in the deflector (14). 4. The combustion chamber (1) according to claim 1 or 2, characterized in that the injection system (6) comprises a rotation blocking tab (10a) locked against rotation by circumferential stops (20a, 23a) of the sleeve (12) and/or a closing ring (13). 5. The combustion chamber (1) according to claim. 4, characterized in that the sleeve (12) contains the first circumferential stop (20b) and the second circumferential stop (20a), while the tab (10a) of the rotation lock is made with the ability to come into the support position on the first circumferential stop (20b) in the first angular position of the injection system (6), and the rotation blocking tab (10a) is configured to come into position of support on the second circumferential stop (20a) in the second angular position of the injection system (6). 6. The combustion chamber (1) according to claim. 4, characterized in that the closing ring (13) contains a third circumferential stop (23a), while the tab (10a) is designed to be held in position between the second and third circumferential stops (20a , 23a) to hold the injection system (6) in its second angular position. 7. Chamber (1) combustion according to any one of paragraphs. 1-5, characterized in that the sleeve (12) contains a radially inner cylindrical part (16) installed in the hole (5) of the bottom wall (4) and fixed on the periphery of the said hole (5). 8. The combustion chamber (1) according to claim 6, characterized in that the deflector (14) contains a cylindrical part (15) installed in the radially inner cylindrical part (16) of the sleeve (12) and attached to the said radially inner cylindrical part (16 ). 9. Chamber (1) combustion according to any one of paragraphs. 1-7, characterized in that the sleeve (12) contains a radially outer cylindrical part (20) located in the axial direction upstream from the radially inner cylindrical part (16), while the closing ring (13) is installed radially inside the radially outer cylindrical parts (20). 10. The method of assembling the combustion chamber (1) according to any one of paragraphs. 1-9, characterized by the fact that it includes the following steps, in which: - the sleeve (12) and the deflector (14) are attached to the bottom wall (4), - the injection system (6) is placed in the first angular position and is inserted into the hole (5) of the bottom wall (4) through the sleeve (12) and the deflector (14) by translational movement along the axis (A) of the injection system (6) and the specified hole (5), while the protruding part (18) passes through the hollow part (26), - the injection system (6) is rotated to its second angular position so that the protruding part (18) forms an axial stop with a deflector (14), - install the closing ring (13) so as to hold in the axial direction the annular shoulder (10) of the injection system (6) in the groove (11) bounded by the closing ring (13) and the sleeve (12), and to lock the system (6) from rotation ) injection.

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