阅读说明：本技术 用于涡轮机的燃烧室 (Combustion chamber for a turbomachine ) 是由 杰克奎斯·马塞尔·阿瑟·布内尔 威廉姆·劳伊斯·罗多尔夫·道塞 本杰明·弗朗茨·卡尔·维莱纳维 于 2020-02-19 设计创作，主要内容包括：本发明涉及一种燃烧室,所述燃烧室包括：底壁(4),所述底壁具有至少一个开口(5)；至少一个套筒(12),所述套筒安装在所述底壁(4)的上游且固定到所述底壁(4)；闭合环(13),所述闭合环与所述套筒(12)限定环形凹槽(11)且固定到所述套筒(12)；至少一个空气和燃料喷射系统(6),所述空气和燃料喷射系统具有轴线(A),安装在所述底壁(4)的所述开口(5)中,所述喷射系统(6)包括相对于所述轴线(A)径向延伸的环形凸缘(10),所述环形凸缘安装在具有径向间隙的所述凹槽(11)中；挡板(14),所述挡板位于所述底壁(4)的下游,固定到所述套筒(12)和/或所述底壁(4)。(The present invention relates to a combustion chamber comprising: a bottom wall (4) having at least one opening (5); at least one sleeve (12) mounted upstream of the bottom wall (4) and fixed to the bottom wall (4); a closing ring (13) defining an annular groove (11) with the sleeve (12) and fixed to the sleeve (12); -at least one air and fuel injection system (6) having an axis (a) mounted in said opening (5) of said bottom wall (4), said injection system (6) comprising an annular flange (10) extending radially with respect to said axis (a), said annular flange being mounted in said groove (11) with radial clearance; a baffle (14) located downstream of the bottom wall (4), fixed to the sleeve (12) and/or to the bottom wall (4).)

1. A combustion chamber (1) for a turbomachine, comprising

-a bottom wall (4) comprising at least one opening (5),

-at least one sleeve (12) mounted upstream of the bottom wall (4) and fixed to the bottom wall (4),

-a closing ring (13) defining an annular groove (11) with the sleeve (12) and fixed to the sleeve (12),

-at least one air and fuel injection system (6) having an axis (A) mounted in said opening (5) of said bottom wall (4), said injection system (6) comprising an annular flange (10) extending radially with respect to said axis (A), said annular flange being mounted in said groove (11) with radial clearance,

-a baffle (14) located downstream of the bottom wall (4), fixed to the sleeve (12) and/or to the bottom wall (4), comprising a radially inner portion located axially between the bottom wall (4) and a downstream end of the injection system (6),

characterized in that said injection system (6) comprises at least one protruding portion (18) that can be introduced into a recessed portion (16) of said baffle (14) at a first angular mounting position of said injection system (6) with respect to said baffle (14), or vice versa, said protruding portion (18) being able to be in a second angular position for holding said injection system (6) with respect to said baffle (14) at said baffle (14)

Or respectively on a radial or downstream face of the injection system (6), the protruding portion (18) being angularly offset from the recessed portion (16) in the second position.

2. The combustion chamber (1) according to claim 1, characterized in that it comprises position retaining means (10a, 23a) able to retain the injection system (6) in its second position with respect to the baffle (14).

3. The combustion chamber (1) according to claim 1, characterized in that said protruding portion (18) extends radially from said downstream end of said injection system (6), said recessed portion (16) being formed in said baffle plate (14).

4. The combustion chamber (1) according to claim 1 or 2, characterized in that the injection system (6) comprises a rotation blocking lug (10a) fixed in rotation by a circumferential stop (20a, 23a) of the sleeve (12) and/or of the closure ring (13).

5. The combustion chamber (1) according to claim 4, characterized in that the sleeve (12) comprises a first circumferential stop (20b) and a second circumferential stop (20a), the rotation-blocking lug (10a) being able to rest on the first circumferential stop (20b) in the first angular position of the injection system (6), the rotation-blocking lug (10a) being able to rest 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 closure ring (13) comprises a third circumferential stop (23a), the lug (10a) being retainable in a position between the second and third circumferential stops (20a, 23a) in order to retain the injection system (6) in its second angular position.

7. A combustion chamber (1) according to any of the claims from 1 to 5, characterized in that said sleeve (12) comprises a radially internal cylindrical portion (16) mounted in said opening (5) of said bottom wall (4) and fixed to the periphery of said opening (5).

8. A combustion chamber (1) according to claim 6, characterized in that said baffle (14) comprises a cylindrical portion (15) mounted in said radially inner cylindrical portion (16) of said sleeve (12) and fixed to said radially inner cylindrical portion (16).

9. The combustion chamber (1) according to any one of claims 1 to 7, characterised in that the sleeve (12) comprises a radially outer cylindrical portion (20) axially upstream of the radially inner cylindrical portion (16), the closure ring (13) being mounted radially inside the radially outer cylindrical portion (20).

10. A method for assembling a combustion chamber (1) according to one of the claims 1 to 9, characterized in that it comprises the steps of:

-fixing the sleeve (12) and the baffle (14) to the bottom wall (4),

-positioning an injection system (6) in a first angular position and introducing the injection system (6) into the opening in the bottom wall (4) by translating along an axis (A) of the injection system (6) and the opening (5) through the sleeve (12) and the baffle (14), a protruding portion (18) passing through a recessed portion (26),

-pivoting the injection system (6) into its second angular position such that the protruding portion (18) can form an axial stop with the baffle (14),

-mounting a closure ring (13) so as to retain an annular flange (10) of the injection system (6) in a groove (11) delimited by the closure ring (13) and the sleeve (12), and fixing the injection system (6) against rotation.

Technical Field

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

Background

Fig. 1 shows a portion of an annular combustion chamber 1 of a turbomachine, such as a turbojet or an airplane turboprop, according to the prior art.

The combustion chamber 1 is located at the outlet of a diffuser (not shown) which is itself located at the outlet of the compressor. The chamber 1 is composed of an inner rotary wall 2 and an outer rotary wall 3 connected upstream to a chamber bottom wall 4.

The chamber bottom wall 4 has an opening 5 for mounting an injection system 6 of a mixture of air and fuel in the chamber 1, wherein the air from the diffuser and the fuel supplied by injectors (not shown) are evenly distributed over the circumference of the combustion chamber 1. Each injector comprises a fuel injection head aligned with the axis a of the corresponding opening 5.

The portion of the air flow supplied by the compressor and exiting the diffuser feeds the inner and outer annular ducts that bypass the combustion chamber. Another part of the air flow enters the injection system and is then mixed with the fuel supplied by the injectors before being 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. A bowl 8 surrounds the annular wall, said bowl 8 opening out downstream. The injection system 6 conventionally comprises fins 9 designed to generate a swirling motion of the air flow passing through it, so as to facilitate homogenization of the air and fuel mixture.

The radially outer periphery of the bowl comprises a radial flange 10 mounted movably in a radial groove 11 delimited by a sleeve 12 welded to the bottom wall 4 of the combustion chamber 1 and by a closure ring 13 welded to the sleeve 12.

The radial displacement of the flange 10 in the groove 11 may compensate for the relative displacement between the injector and the casing of the turbine, on the one hand the injector being attached to the casing of the turbine and on the other hand the combustion chamber 1. This displacement occurs during operation due to the different expansions between the various components of the turbine.

A baffle 14 is further mounted downstream of the bottom wall 4, the baffle 14 comprising a cylindrical portion 15 mounted within a cylindrical portion 16 of the sleeve 12 and fixed to said cylindrical portion 16 of the sleeve 12 by brazing or welding.

There is a risk that the baffle 14 may become detached from the sleeve 12, causing damage to downstream components, particularly the turbine.

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

Disclosure of Invention

For this purpose, the invention relates to a turbomachine combustion chamber comprising:

-a bottom wall comprising at least one opening,

-at least one sleeve mounted upstream of the bottom wall and fixed thereto,

a closing ring defining an annular groove with the sleeve and fixed to the sleeve,

-at least one air and fuel injection system having an axis, mounted in an opening of the bottom wall, said injection system comprising an annular flange extending radially with respect to said axis, said annular flange being mounted in said groove with a radial gap,

a baffle plate downstream of the bottom wall, fixed to the sleeve and/or to the bottom wall, said baffle plate comprising a radially inner portion axially between the bottom wall and the downstream end of the injection system,

characterized in that the injection system comprises at least one protruding portion that can be introduced into a recessed portion of the baffle plate at a first angular mounting position of the injection system relative to the baffle plate, or vice versa, the protruding portion being axially abuttable on a radial or downstream face of the baffle plate or respectively of the injection system in a second angular position for retaining the injection system relative to the baffle plate, the protruding portion being angularly offset from the recessed portion in the second position.

The baffle and the injection system therefore comprise a bayonet-type system which allows the injection system to be mounted in the baffle in a first angular position and axially retain the baffle with respect to the injection system in a second angular position. In the case of separation of the baffle on the one hand and separation of the sleeve and/or the bottom wall on the other hand, the baffle remains axially retained by the projecting portion, so that there is no risk of damage to the downstream components of the turbomachine.

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

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

The combustion chamber may comprise position retaining means adapted to retain the injection system in its second position relative to the baffle.

The projection may extend radially from a downstream end of the injection system, the recess being formed in the baffle.

The protruding portion is formed, for example, by a lug or tab extending radially outward. The recessed portion is formed, for example, by a groove or recess in the baffle.

The number of the protruding portions and the recessed portions is, for example, three. The protruding portions and the recessed portions may be evenly distributed around the circumference.

The injection system may comprise a rotation blocking lug which is held or fixed in rotation by a circumferential stop of the sleeve and/or the closure ring.

The sleeve may comprise a first circumferential stop and a second circumferential stop, the rotation blocking lug being adapted to abut the first circumferential stop in a first angular position of the injection system, the rotation blocking lug being adapted to abut the second circumferential stop in a second angular position of the injection system.

The circumferential stop thus forms an end stop, allowing and limiting the angular deflection of the injection system with respect to the baffle. This structure allows for facilitated installation of the assembly.

The closure ring may comprise a third circumferential stop, the lugs being adapted to be held in position between the second and third circumferential stops in order to maintain the injection system in its second angular position.

Thus, the second and third circumferential stops form the above-mentioned position-retaining means together with the position-retaining lugs.

The sleeve may comprise a radially inner cylindrical portion mounted in the opening in the bottom wall and attached to the outer periphery of the opening.

The corresponding fastening is done, for example, by soldering or welding.

The baffle may comprise a cylindrical portion mounted in and attached to a radially inner cylindrical portion of the sleeve.

The corresponding fastening is done, for example, by soldering or welding.

The sleeve may comprise a radially outer cylindrical portion axially upstream of a radially inner cylindrical portion, the closure ring being mounted radially within the radially outer cylindrical portion.

The combustion chamber may comprise an injector with an injection head mounted in an injection system comprising means for supplying air and means for forming a mixture of air and fuel from the injector.

The invention also relates to a turbomachine for an aircraft, comprising an assembly of the aforementioned type.

The invention also relates to a method for assembling a combustion chamber of the above-mentioned type, characterized in that it comprises the following steps:

-fixing the sleeve and the baffle to the bottom wall,

-positioning the injection system in a first angular position and introducing the injection system into the opening in the bottom wall by translating along the axis of the injection system and said opening through the sleeve and the baffle, said protruding portion passing through the recessed portion

Pivoting the injection system into its second angular position so that the protruding portion can form an axial stop with the shutter,

-mounting the closure ring so as to axially retain an annular flange of the injection system in a groove delimited by the closure ring and the sleeve, and fixing the injection system against rotation.

Drawings

Figure 1 is an axial cross-sectional view of a portion of a prior art combustor,

fig. 2 is a view corresponding to fig. 1, illustrating a combustion chamber according to an embodiment of the present invention,

figure 3 is a perspective view of the spraying system,

figure 4 is a perspective view of the spraying system,

figure 5 is a perspective view of the baffle,

fig. 6 is a perspective view of a portion of a combustion chamber according to the invention, the injection system being in its second angular position with respect to the baffle,

figure 7 is a perspective view showing the sleeve, the chamber bottom and the injection system in a second angular position of the injection system,

fig. 8 is a view corresponding to fig. 7, wherein a closed loop has been added.

Detailed Description

Fig. 2 to 8 illustrate part of a combustion chamber 1 according to one embodiment of the invention, intended to be equipped with a turbomachine, for example a turbojet or an airplane turboprop.

The chamber 1 is composed of an inner and an outer rotating wall connected upstream to a bottom annular wall 4 of the chamber.

The chamber bottom wall 4 has an opening 5 for mounting an injection system 6 of a mixture of air and fuel in the chamber 1, wherein the air from the diffuser and the fuel supplied by injectors (not shown) are evenly distributed over the circumference of the combustion chamber 1. Each injector comprises a fuel injection head aligned with the axis a of the corresponding opening 5.

The portion of the air flow supplied by the compressor and exiting the diffuser feeds the inner and outer annular ducts that bypass the combustion chamber. Another part of the air flow enters the injection system and is then mixed with the fuel supplied by the injectors before being 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. A bowl 8 surrounds the annular wall, said bowl 8 opening out downstream.

The downstream end of the bowl 8 includes a radially outwardly extending annular flange 17. As best seen in fig. 3 and 4, a lug or tab 18 extends radially outwardly from the radially outer periphery of the annular flange 17. In this case there are three lugs and they are distributed evenly around the circumference, i.e. they are angularly offset from each other by an angle of 120 °.

The injection system 6 conventionally also comprises fins 9 designed to generate a gyrating motion of the air flow entering through the channels defined between the bowl 8 and the annular wall, so as to facilitate the homogenization of the air and fuel mixture.

The radially outer periphery of the bowl has a radial flange 10 connected to the flange 17 by a cylindrical portion 19. The flange 10 is located axially upstream of the flange 17. The flange 10 is movably mounted in a radial groove 11 delimited by a sleeve 12 welded to the bottom wall 4 of the combustion chamber 1 and by a closing ring 13 welded to the sleeve 12. The flange 10 has a tab 10a extending radially outwardly from the radially outer end of the flange 10.

The radial displacement of the flange 10 in the groove 11 may compensate for the relative displacement between the injector and the casing of the turbine, on the one hand the injector being attached to the casing of the turbine and on the other hand the combustion chamber 1. This displacement occurs during operation due to the different expansions between the various components of the turbine.

More specifically, the sleeve 12 comprises, from upstream to downstream, a cylindrical portion 20, a radially extending annular portion 21 and a cylindrical portion 16. The cylindrical portion 20 has a larger diameter than the cylindrical portion 16. The cylindrical portion 16 is mounted in the opening 5 of the bottom wall and is fixed to said bottom wall 4 by welding or brazing. The radially inner region of the radial portion 21 has a downstream support surface resting on the bottom wall 4.

The cylindrical portion 20 extends over only a portion of the circumference. In particular, as can be better seen in fig. 7, the sleeve has an angular sector without the cylindrical portion 20, which extends here over 120 °. The circumferential ends 20a, 20b of the cylindrical portion 20 are adapted to form a stop for the tabs 10a, which are housed in said angular sectors without the cylindrical portion 20.

The closed ring 13 is generally T-shaped in cross-section having an annular radial portion 22 and an annular cylindrical portion 23. The downstream end of the cylindrical portion 23 rests on the radial portion 21 of the sleeve 12. Said radial portion 21 of the sleeve 12 and the radial portion 22 of the closure ring 23 are therefore axially spaced from each other and define the groove 11 therebetween.

The downstream end of the cylindrical portion 23 has a notch 23a (fig. 8), the function of which is explained below.

A baffle 14 is also mounted downstream of the bottom wall 4.

The baffle 14 includes, from upstream to downstream, a cylindrical portion 15, a radial portion 24 having an annular sector, and flanges 25 extending axially downstream at radially inner and outer edges of the radial portion 24. The cylindrical portion 15 is mounted within a cylindrical portion 16 of the sleeve 12 and is fixed to said cylindrical portion 16 by brazing or welding.

The cylindrical portion 16 also has grooves 26 (here three) evenly distributed around the circumference.

This combustion chamber is installed as described below.

The sleeve 12, in particular the cylindrical portion 16, is first mounted in the opening 5 of the bottom wall 4. The baffle 14, in particular the cylindrical portion 15, is mounted in the cylindrical portion 16 of the sleeve. The cylindrical portion 16, the cylindrical portion 15 and the bottom wall are then joined to each other by welding or brazing.

The injection system is then mounted in the opening 5 of the bottom wall by means of the sleeve 12 and the baffle 14. In particular, the injection system is located in a first angular position, such that the lug 18 of the injection system 6 is positioned opposite the groove 26 of the shutter 14. The injection system is then moved downstream by translation until the flange 10 rests on the radial portion 21 of the sleeve. The lug 18 is then located just downstream of the radial portion 24 of the baffle and the tab 10a is received in the region of the sleeve 12 that does not have the cylindrical flange 20.

The injection system 16 is then rotated to a second angular position illustrated in fig. 6-8. In particular, the injection system is rotated between the first and second angular position by an angle of 60 ° corresponding to half the angular distance between two grooves 26 or between two lugs 18.

In the second angular position, the tabs 10a of the injection system 6 rest on the circumferential stops 20a to facilitate assembly.

In the second angular position, the lug 18 is offset from the groove 26 and can rest on the radial portion 24 of the baffle 14, so as to prevent axial displacement of the injection system 6.

The closure ring 13 is mounted in the cylindrical portion 20 of the sleeve 10 such that the tabs 10a are received and held in place in the notches 23 a. The closure ring 13 is then attached to the sleeve 12 by welding or brazing. Thus preventing the injection system 6 from rotating.

This structure ensures simple assembly of the assembly, while preventing removal of the baffle 14 without brazing or welding the cylindrical portion 15. This prevents damage to the part of the turbine located downstream of the bottom wall 4 or combustion chamber 1.