Injection device with slotted injector for combustion chamber

Abstract

The invention relates to a gaseous fuel injection device (10) with a longitudinal axis (X) for mounting in a turbomachine combustion chamber (90). This injection device (10) comprises at least one injector (30) extending from upstream to downstream along a principal axis (R). This injector (30) has an upstream edge (40) and a downstream edge (50). The downstream edge (50) has a slot (51) through which the gaseous fuel exits and which extends over at least a portion of the length of the downstream edge (50). The thickness of the at least one injector (30) decreases from upstream to downstream along a first transverse direction (Y) perpendicular to the principal axis (R). The downstream edge (50) has partitions (60) distributed along the slot (51). Figure 2

Description

Title of the invention: Injection device with injector with slot for combustion chamber

[0001] The invention relates to the field of combustion chambers of aircraft turbomachinery powered by a gaseous fuel such as dihydrogen and air. These aircraft include winged aircraft for civil or military aviation, helicopters, VTOLs, drones, APUs, turbojets, and turboprops.

[0002] In the case where the turbomachine is a twin-spool, twin-flow aircraft turbomachine extending along a longitudinal axis, the upstream compressor compresses the air that has entered the turbomachine from the upstream end. This air is admitted into the combustion chamber of the downstream turbomachine. The hot gases from this combustion are then expanded in a downstream turbine, causing this turbine to rotate. The rotation of this turbine drives the rotor of the turbomachine on which this turbine is mounted. The rotor, in turn, drives the rotation of the compressor and the fan blades located upstream of the turbomachine. The rotation of the fan blades, along with the high-speed ejection of the gases exiting the combustion chamber, contributes to the propulsion of the turbomachine.

[0003] The combustion chamber is annular and includes a plurality of injection devices which are distributed circumferentially on the bottom of the combustion chamber and which inject the fuel into the combustion chamber.

[0004] Thus, a gaseous fuel injection device with longitudinal axis X intended to be mounted in a turbomachine combustion chamber is known, this injection device comprising at least one injector extending from upstream to downstream along a principal axis R, the at least one injector having an upstream edge and a downstream edge.

[0005] During operation of the turbomachine, difficulties may sometimes be encountered in the gaseous fuel injection device, including flame instability downstream of the injectors in the operating range of the turbomachine, flame sticking at the downstream end of the injectors, and the phenomenon of "flashback" (flame returning upstream).

[0006] Furthermore, for environmental reasons, efforts are being made to use gaseous fuels other than kerosene (which is not gaseous), which emit fewer polluting carbon dioxide gases such as NOx, particulate matter, and fumes. One such less polluting fuel is dihydrogen. However, using dihydrogen as a fuel exacerbates the above-mentioned drawbacks, especially the risk of flashback and combustion instabilities, because the flame speed is approximately ten times faster for hydrogen than for kerosene. Description of the invention

[0007] The present invention aims to remedy these drawbacks.

[0008] The invention aims to provide an injection device that provides more stable combustion over the entire combustion range, i.e. flame stability over the operating range of the turbomachine, and with a reduction or elimination of the flashback phenomenon.

[0009] This goal is achieved thanks to the fact that the downstream edge has a slot through which the gaseous fuel exits and which extends over at least part of the length of the downstream edge, the thickness of at least one injector along a first transverse direction Y perpendicular to the main axis R decreasing from upstream to downstream, the downstream edge having separations which are distributed along the slot and which separate said slot into sections.

[0010] Thanks to these arrangements, the reduced thickness of the slot in the direction of gas flow through the injection device and the separations of this slot contribute to more effectively forming vortices in the gas flow, particularly downstream of the downstream edge. This improves the mixing between the gas and the fuel and helps prevent flame sticking to the injectors, stabilizes the flame, and avoids flame flashback phenomena, especially when the fuel is hydrogen.

[0011] For example, the upstream edge is straight perpendicular to the first transverse direction Y and the downstream edge has an undulation along the first transverse direction Y which extends on either side of the plane formed by the upstream edge and the main axis R.

[0012] For example, the undulation is periodic and is entirely curvilinear.

[0013] For example, the distance between the separations is less than twice the wavelength of the ripple.

[0014] For example, the injector has, at least on its downstream portion, a convergent shape from upstream to downstream.

[0015] For example, the injection device comprises at least two flanges and at least one injector extending in a plane defined by the principal axis R which is parallel to the longitudinal axis X and a second transverse direction Z perpendicular to the first transverse direction Y and to the principal axis R, each of the at least two flanges extending in a plane parallel to this plane and the at least one injector being located between two adjacent flanges.

[0016] For example, the injection device comprises at least two coaxial annular flanges with longitudinal axis X, such that at least one injector is located between two adjacent flanges, and is annular and coaxial with these flanges, the principal axis R is parallel to the longitudinal axis X, the first transverse direction Y being radial and a second transverse direction Z perpendicular to the first transverse direction Y and to the principal axis R being circumferential.

[0017] For example, the injection device includes at least one helical flange with longitudinal axis X, such that at least one injector is helical and extends over at least a part of its helical length between two radially adjacent portions of at least one flange and is coaxial with at least one flange, the principal axis R is parallel to the longitudinal axis X, the first transverse direction Y being radial and a second transverse direction Z perpendicular to the first transverse direction Y and to the principal axis R being circumferential.

[0018] For example, the injection device comprises at least two radial injectors, each extending in a radial plane with respect to the main axis (R) which is parallel to the longitudinal axis (X), and it comprises at least two flanges, each of said planes extending along a second radial transverse direction (Z) perpendicular to the first circumferential transverse direction (Y) and to the main axis (R), each of the at least two flanges being radial and located between two adjacent injectors.

[0019] For example, the injection device includes at least two radial injectors, each extending in a radial plane with respect to the main axis (R), which is radial and perpendicular to the longitudinal axis (X), and it includes at least two flanges, each of the planes extending along a second transverse direction (Z) parallel to the longitudinal axis (X) and perpendicular to the first transverse direction (Y), which is circumferential, each of the at least two flanges being radial and located between two of the adjacent injectors.

[0020] The invention also relates to a combustion chamber comprising a plurality of injection devices according to the invention, distributed along the bottom of this chamber.

[0021] The invention also relates to a turbomachine comprising a combustion chamber according to the invention.

[0022] The invention will be better understood and its advantages will become more apparent upon reading the following detailed description of embodiments shown by way of non-limiting examples. The description refers to the accompanying drawings in which:

[0023] [Fig-1] Fig. 1 is a longitudinal cross-sectional view of a combustion chamber of a turbomachine carrying an injection device according to the invention.

[0024] [Fig.2] Fig.2 is a side view along the second transverse axis Y of a injection device according to the invention.

[0025] [Fig.3] Fig.3 is a front view along the longitudinal axis X of a device injection according to a first embodiment of the invention.

[0026] [Fig.4] The [Fig.4] is a perspective view of an injector of an injection device according to the invention with undulations of the downstream edge.

[0027] [Fig.5] The [Fig.5] is a front view along the longitudinal axis X of an injection device with the injector of the [Fig.4].

[0028] [Fig.6] Fig.6 is, in A: a cross-sectional view along the VLA line of the injection device of [Fig.5]; in B: a cross-sectional view along the VLB line of the injection device of [Fig.5]; in C: a cross-sectional view along the VLC line of the injection device of [Fig.5].

[0029] [Fig.7] Fig.7 is, in A: a cross-sectional view along line VILA of a variant of the injection device of [Fig.5]; in B: a cross-sectional view along line VILB of a variant of the injection device of [Fig.5]; in C: a cross-sectional view along line VILC of a variant of the injection device of [Fig.5].

[0030] [Fig.8] The [Fig.8] is a front view along the longitudinal axis X of an injection device according to a second embodiment of the invention.

[0031] [Fig.9] The [Fig.9] is a front view along the longitudinal axis X of an injection device according to a third embodiment of the invention.

[0032] [Fig. 10] The [Fig. 10] is a front view along the longitudinal axis X of an injection device according to a fourth embodiment of the invention.

[0033] [Fig. 11] The [Fig. 11] is a cross-sectional view along line XLXI of a part of the injection device of the [Fig. 10].

[0034] [Fig. 12] The [Fig. 12] is a front view along the longitudinal axis X of an injection device according to a fifth embodiment of the invention.

[0035] [Fig. 13] The [Fig. 13] is a cross-sectional view along line XIIXIII of part of the injection device of the [Fig. 12]. Detailed description of the invention

[0036] In the description below, the terms "internal" and "inner" refer to an element oriented towards a reference axis or located closer to that axis. The terms "external" and "outer" refer to an element oriented in the opposite direction to that reference axis or located further from that axis. The terms "upstream" and "downstream" are relative to the direction of air and gas flow during the operation of the turbomachine, i.e., from left to right in [Fig. 1]. The term "radial" refers to a position or direction in a transverse plane perpendicular to the reference axis and passing through that reference axis.

[0037] Consider a turbomachine with longitudinal axis A, which is its axis of rotation. This turbomachine comprises a compressor, a combustion chamber 90, and a turbine. The combustion chamber 90 is located in a section of the turbomachine downstream of the compressor and upstream of the turbine. The air is compressed by the compressor The air enters combustion chamber 90, and fuel is injected into this combustion chamber 90 where it is burned with this compressed air. The hot gases generated by this combustion are ejected at high speed into the turbine.

[0038] As shown in [Fig. 1], the combustion chamber 90 is annular and is mounted between an inner shell 91 and an outer shell 92, which are cylindrical and coaxial with longitudinal axis A. These two shells (91, 92) define an annular space that is open upstream to a diffuser 93 which communicates with the compressor (not shown). The combustion chamber 90 is delimited by a bottom wall 94 located upstream, an inner shell 95 and an outer shell 96 coaxial with longitudinal axis A, and is open downstream to the turbine. The shells (95, 96) are assembled and fixed to the shells (93, 94) by flanges. The bottom wall 94 is substantially transverse with respect to the gas flow axis in the combustion chamber 90 and is provided with a plurality of circular openings 97. A fairing 98 located upstream of these openings 97 guides the air from the diffuser 93 towards these openings 97.For each opening 97, fuel is supplied via a pipe 99 to an injection device 10, which atomizes the fuel into the airflow to form a mixture. This mixture enters the combustion chamber 90 along a longitudinal axis X, which is the central axis of the injection device 10 and the direction of gas flow exiting the injection device 10. The longitudinal axis X passes through the center of the injection device 10. The longitudinal axis X is defined relative to the injection device 10 and is therefore of constant orientation. The injection device 10 is delimited by a wall 11. For example, this wall is cylindrical with a circular cross-section, as shown in the figures. The principal axis X of the injection device 10 is parallel, or not parallel, to the longitudinal axis A.

[0039] For each injector 30 (see below), a principal axis R is defined which gives the direction of air inlet at the upstream edge of the injector 30 and which is the axis along which this injector 30 extends from upstream to downstream. The principal axis R also gives the direction of gas (e.g., hydrogen) flow in an injector 30. The principal axis R is generally parallel to the longitudinal axis X (first, second, third, and fourth embodiments below); however, in the radial embodiment of the injection device 10 (fifth embodiment below), the principal axes R of the injectors are perpendicular to the longitudinal axis X. A first transverse direction Y (first transverse axis Z) is defined, perpendicular to the principal axis R, and a second transverse direction Z (second transverse axis Z) is defined, perpendicular to the first transverse direction Y and to the principal axis R.The thickness of an injector 30 is along the first transverse direction Y. A transverse plane is defined which is perpendicular to the principal axis. R, and which therefore extends along the first transverse direction Y and the second transverse direction Z. The transverse directions (Y, Z) are defined at a given point of an injector 30. The transverse directions (Y, Z) are therefore either of constant orientation if the injector(s) 30 extend in parallel planes (first embodiment below), or of variable orientation if the injector(s) 30 are curved or are arranged radially (second, third, fourth and fifth embodiments below).

[0040] The injection device 10 optionally includes at least one flange 20 and at least one injector 30 extending from upstream to downstream along the main axis R (main direction R). The flange(s) 20 extend along the main axis R, or alternatively, extend along an axis distinct from the main axis R. The injector 30, or in certain embodiments, each of the injectors 30, is surrounded by one or two adjacent flanges 20. Thus, two adjacent flanges 20 define a space in which an injector 30 is located, and the amount of air passing around the injector 30 can be regulated by adjusting the distance between these two adjacent flanges 20.Depending on the geometry of the flanges 20, this space is for example rectangular in section (first embodiment below), annular in section (second embodiment below), helical in section (third embodiment below) or triangular in section (fourth and fifth embodiments below).

[0041] The injector(s) 30 have an upstream edge 40 (leading edge with respect to the gas flow), and a downstream edge 50 (trailing edge with respect to the gas flow), these two edges (40, 50) extending perpendicularly to the main axis R. The downstream edge 50 of an injector 30 can be located at the same level, upstream or downstream along the longitudinal direction R with respect to the downstream edge of a flange 20 which is adjacent to this injector 30. The upstream edge 40 is for example rounded.

[0042] The downstream edge 50 has a slot 51 through which the gaseous fuel exits and which extends over at least a part of, for example over the entire, length of the downstream edge 50. This length is that of a curve which follows the downstream edge 50. The slot 51 opens downstream and the gaseous fuel enters the combustion chamber 90 through the slot 51. The thickness of the injector 30 along the first transverse direction Y perpendicular to the main axis R decreases from upstream to downstream over at least a part of its length (along the main axis R) up to its downstream edge 50. Thus, the injector 30 has, at least on its downstream portion, a convergent shape from upstream to downstream. In other words, the downstream portion of injection 30 has a substantially trapezoidal shape in the plane defined by the first transverse direction Y and the principal axis R. Optionally, each of the walls of this downstream portion is straight in this plane.Advantageously, the non-zero angle of this convergence (that is- . that is, the angle 0 of the walls of the injector 30 with respect to the main axis R) is less than 35°. For example, the angle of this convergence is small compared to a right angle, for example less than 5°, for example less than 2°, for example less than 1° (this angle is visible in [Fig. 2]). For example, the angle of this convergence is between 2° and 35°. Thus, we help to reduce the region downstream of the injector 30 where the gas velocity is lower, and consequently we help to prevent the flame from sticking to the injector 30.

[0043] Advantageously, the walls of the injector 30 have a constant thickness that is small compared to the minimum thickness of the injector 30 (along the first transverse direction Y), i.e., the thickness of the injector 30 at its downstream edge 50. For example, the wall thickness is less than 10% of the thickness of the injector 30 at its downstream edge 50. Thus, the region downstream of the injector 30 where the gases have a lower velocity is reduced, and consequently, the region downstream of the injector 30 is helped to prevent the flame from adhering to the injector 30.

[0044] For example, the injection device 10 comprises two flanges 20 and an injector 30 sandwiched between these two flanges 20. This injection device 10 is illustrated in [Fig.2] which is a cross-sectional view in a plane perpendicular to the second transverse direction Z, i.e. the plane defined by the first transverse direction Y and the principal axis R.

[0045] Separations 60 are arranged along the downstream edge 50 and divide the slot 51 into several sections. These separations 60 extend over at least a portion of the upstream-downstream length of the injector 30. For example, these separations 60 are evenly distributed along the downstream edge 50. Advantageously, these separations 60 are irregularly distributed relative to each other, i.e., the distances between two adjacent separations 60 are not equal. Thus, the air-fuel mixture downstream of the slot 51 is optimized. The separations 60 are visible in [Fig. 2], [Fig. 3], and [Fig. 5].

[0046] A first embodiment of the invention is described below in which the injectors 30 each extend in a distinct plane.

[0047] The injection device 10 comprises a plurality of flanges 20 that are substantially flat and parallel to each other, and at least one injector 30, each injector 30 being located between two adjacent flanges 20. The flanges 20 and the injectors 30 each extend in a plane along the longitudinal directions X and Z. The first transverse direction Y is therefore perpendicular to the flanges 20 and the injectors 30. The first transverse direction Y and the second transverse direction Z are constant. The principal direction R is the same as the longitudinal direction X. This configuration is shown in [Fig. 3] in the case of four flanges 20 and three injectors 30.

[0048] In one embodiment, the downstream edge 50 extends along the second transverse direction Z and has a waviness 53 along the first transverse direction Y. By "an edge which extends along a direction S has a waviness along a direction T" it is meant that the edge has the form of a periodic or non-periodic function F of equation t = F(s) in the frame whose abscissa "s" is along the direction S and the ordinate "t" is along the direction T.

[0049] Figure 4 illustrates an injector 30 in perspective, where the undulation 53 is visible. The upstream edge 40 is straight and extends along the second transverse direction Z. Alternatively, the upstream edge 40 has a first undulation along the first transverse direction Y perpendicular to the main direction R and / or a second undulation along the main direction R.

[0050] When periodic, the ripple 53 can have any shape. For example, as illustrated in the figures, the ripple 53 is sinusoidal, that is to say that the function t = F(s) defining the ripple 53 is a sinusoid.

[0051] The undulation of the downstream edge 50 contributes to the more efficient formation of vortices in the gas flow passing through the injection device 10, particularly downstream of the trailing edge 50 of the injectors 30. This helps to stabilize a lifted flame downstream of the injector 30 and prevent the flame from catching on the injector 30. For example, the wavelength of the undulation 53 and the distance between the separations 60 can be equal or a multiple of each other. By varying this wavelength and distance, the mixing of the gaseous fuel and air and the flame properties downstream of the injector 30 can be optimized. For example, the distance between the separations 60 is less than twice the wavelength of the undulation 53. Optionally, the downstream edge 50 also has an undulation along the principal direction R.

[0052] Advantageously, the undulations are entirely curvilinear, meaning that the edges have no angles. In other words, the function t = F(s), which represents an undulation on an edge, has no inflection point. This simplifies the manufacturing of the injectors 30. In particular, the injectors 30 can be manufactured by additive manufacturing or by injection molding.

[0053] Figure 5 illustrates an injector 30 surrounded by two flanges 20, viewed from the front, i.e., perpendicular to the main axis R. The flanges 20 have at their downstream end a corrugation similar to that of the downstream edge 50, which allows for a substantially constant distance between this downstream edge 50 and each of the flanges 20. Alternatively, the corrugation of the flanges 20 is out of phase with the corrugation of the downstream edge 50, which contributes to the formation of vortices in the gas flow.

[0054] Figure 6A is a cross-sectional view in the (R, Y) plane of the injector 30 and the flanges 20 of [Fig. 5], at a maximum of the downstream edge 50 (this maximum is measured in the direction of the first transverse axis Y). The injector 30 extends, at its upstream edge 40 in the (R, Z) plane, which is here the (X, Z) plane, then curves upwards, progressing from upstream to downstream until the downstream edge 50. The gas therefore exits upwards through the slot 51. Figure 6C is a cross-sectional view in the (R, Y) plane of the injector 30 and the flanges 20 of [Fig. 5], at a minimum of the downstream edge 50 (this minimum is measured in the direction of the first transverse axis Y). The injector 30 extends, at its upstream edge 40 in the (R, Z) plane, then curves downwards, progressing from upstream to downstream until the downstream edge 50. The gas therefore exits downwards through the slot 51. Figure 6B is a cross-sectional view in the (R, Y) plane of the injector 30 and flanges 20 of [Fig.5], at the level of the median plane (R, Z) of the downstream edge 50. The injector 30 extends from its upstream edge 40 to its downstream edge 50 in the median plane (R, Z).The gas therefore exits along the main direction R through the slit 51.

[0055] Figures 7A, 7B and 7C represent cross-sections identical to Figures 6A, 6B and 6C in the case where the downstream edge 50 of the injector 30 is curved towards the main direction R such that the gas exits through the slot 51 always in the main direction R, regardless of the position along the downstream edge 50. In positions where the downstream edge 50 crosses its median plane, the downstream edge 50 remains straight since the slot 51 is already perpendicular to the main direction R. [Fig. 5] is identical in the two cases above: downstream edge 50 curved to extend along the main axis R (Figures 7A, 7B, 7C) or not (Figures 6A, 6B, 6C).

[0056] In all embodiments of the invention, and in particular the first embodiment described above and the other embodiments described below, the variant where the downstream edge 50 has a corrugation 53 is possible. This corrugation may also be absent.

[0057] A second embodiment of the invention is described below in which the injectors 30 are annular.

[0058] The injection device 10 comprises a plurality of coaxial annular flanges 20 with longitudinal axis X and a plurality of coaxial annular injectors 30 with the flanges 20, each injector 30 being located between two adjacent flanges 20, with the exception of the most central injector 30 and the injector 30 furthest from the longitudinal axis X. The injectors 30, and therefore their upstream edges 40 and their downstream edges 50, are curved. If present, the undulation of the downstream edge 50 follows this curve. The principal direction R coincides with the longitudinal direction X. In this configuration, the first transverse direction Y is radial and the second transverse direction Z is circumferential. Thus, the direction of the first transverse direction Y and the direction of the second transverse direction Z vary as one moves along an injector 30 around the longitudinal axis X. This configuration is represented in [Fig.8] in the case of three flanges 20 and two injectors 30. For clarity, the slots 51 are not shown. Alternatively, an additional flange 20 may be located at the center of the most central injector 30 and an additional flange 20 may surround the injector 30 furthest from the longitudinal axis X, such that each injector 30 is located between two adjacent flanges 20.

[0059] A third embodiment of the invention is described below in which the injectors 30 are helical.

[0060] The injection device 10 comprises at least one helical flange 20 with longitudinal axis X and at least one helical injector 30 which is coaxial with this flange 20 and which extends over at least a portion of, for example along its entire helical length between two radially adjacent portions of the flange 20. The injectors 30, and therefore their upstream edges 40 and their downstream edges 50, are curved. If present, the undulation of the downstream edge 50 follows this curve. The principal direction R coincides with the longitudinal direction X. In this configuration, the first transverse direction Y is radial and the second transverse direction Z is circumferential. Thus, the direction of the first transverse direction Y and the direction of the second transverse direction Z vary as one moves along an injector 30 around the longitudinal axis X. This configuration is shown in [Fig.9] in the case of a flange 20 and an injector 30. For clarity, the slots 51 are not shown.

[0061] In the above embodiments, the flanges 20 and injectors 30 are fixed to the wall 11. Alternatively or additionally, the injection device 10 further comprises a support 70 which is integral with the wall 11 and to which the flanges 20 and injectors 30 are fixed. For example, as shown in Figures 3, 8, and 9, the support 70 comprises one or more plates which pass through the longitudinal axis X and which are oriented at different angles.

[0062] A fourth embodiment of the invention is described below in which the injectors 30 are radial and the air inlet in an injector is longitudinal.

[0063] The injection device 10 comprises a plurality of radial injectors 30, each extending in a plane (R, Z) passing through the longitudinal axis X, and a plurality of radial flanges 20, each extending in a plane also passing through the longitudinal axis X, each injector 30 being located between two adjacent flanges 20. Air enters the injection device 10 along the longitudinal direction X. The principal direction R coincides with the longitudinal direction X. In this configuration, the first transverse direction Y is circumferential and the second transverse direction Z is radial. Thus, the direction of the first transverse direction Y and the direction of the second transverse direction Z vary with the position of the injector 30 around the longitudinal axis X. This configuration is shown in [Fig. 10] in the case of four flanges 20 and four injectors 30.

[0064] Fig. 11 is a cross-sectional view in the radial plane (R, Z) of a portion of the injection device 10 which shows an injector 30. Air and gas flow through the injection device 10 in the longitudinal direction X and exit in the longitudinal direction X.

[0065] A fifth embodiment of the invention is described below in which the injectors 30 are radial and the air inlet in an injector is radial.

[0066] The injection device 10 comprises a plurality of radial injectors 30, each extending in a plane (R, Z) passing through the longitudinal axis X, and a plurality of radial flanges 20, each extending in a plane also passing through the longitudinal axis X, each injector 30 being located between two adjacent flanges 20. Unlike the fourth embodiment, air enters the injection device 10 in a radial direction, which is the direction R. The principal direction R is perpendicular to the longitudinal direction X. In this configuration, the first transverse direction Y is circumferential and the second transverse direction Z is longitudinal. Thus, the direction of the first transverse direction Y and the direction of the principal axis R vary with the position of the injector 30 around the longitudinal axis X. This configuration is shown in [Fig. 12] in the case of four flanges 20 and four injectors 30.The flanges 20 may have a curved cross-section, for example in the shape of a blade, in order to optimize the airflow between a flange 20 and an injector 30.

[0067] Figure 13 is a cross-sectional view in the radial plane (R, Z) of a portion of the injection device 10, showing an injector 30. Air and gas enter the injection device 10 in an inward radial direction R. Air and gas exit the injection device 10 in the longitudinal direction X.

[0068] The invention also relates to a combustion chamber comprising a plurality of injection devices 10 as described above. These injection devices are distributed along the bottom 94 of this chamber 90. For example, this chamber is annular.

[0069] The invention also relates to a turbomachine comprising a combustion chamber 90 according to the invention.

Claims

Demands

1. A gaseous fuel injection device (10) with a longitudinal axis (X) for mounting in a turbomachine combustion chamber (90), said injection device (10) comprising at least one injector (30) extending from upstream to downstream along a principal axis (R), said at least one injector (30) having an upstream edge (40) and a downstream edge (50), said at least one injector (30) being characterized in that said downstream edge (50) has a slot (51) through which said gaseous fuel exits and which extends over at least a portion of the length of said downstream edge (50), the thickness of said at least one injector (30) in a first transverse direction (Y) perpendicular to said principal axis (R) decreasing from upstream to downstream to said downstream edge (50), said downstream edge (50) having separations (60) which are distributed along said slot (51) and which separate said slot (51) into sections.

2. Injection device (10) according to claim 1 wherein said upstream edge (40) is straight perpendicular to said first transverse direction (Y) and said downstream edge has a waviness (53) along said first transverse direction (Y) which extends on either side of the plane formed by said upstream edge (40) and said main axis (R).

3. Injection device (10) according to claim 2 such that said undulation (53) is periodic and is entirely curvilinear.

4. Injection device (10) according to claim 3 such that the distance between said separations (60) is less than twice the wavelength of said ripple (53).

5. Injection device (10) according to any one of claims 1 to 4 such that said injector (30) has, at least on its downstream portion, a convergent shape from upstream to downstream.

6. Injection device (10) according to any one of claims 1 to 5, wherein it comprises at least two flanges (20) and at least one injector (30) extending in a plane defined by said principal axis (R) parallel to said longitudinal axis (X) and a second transverse direction (Z) perpendicular to said first transverse direction (Y) and said principal axis (R), each of said at least two flanges (20) extending in a plane parallel to said plane and said at least one injector (30) being located between two of said adjacent flanges (20).

7. Injection device (10) according to any one of claims 1 to 5, wherein it comprises at least two coaxial annular flanges (20) with longitudinal axis (X), wherein said at least one injector (30) is located between two of said adjacent flanges (20) and is annular and coaxial with said flanges (20), said principal axis (R) being parallel to said longitudinal axis (X), said first transverse direction (Y) being radial and a second transverse direction (Z) being perpendicular to said first transverse direction (Y) and said principal axis (R) being circumferential.

8. Injection device (10) according to any one of claims 1 to 5, wherein it comprises at least one helical flange (20) with longitudinal axis (X), wherein said at least one injector (30) is helical and extends over at least a portion of its helical length between two radially adjacent portions of said at least one flange (20) and is coaxial with said at least one flange (20), said principal axis (R) being parallel to said longitudinal axis (X), said first transverse direction (Y) being radial and a second transverse direction (Z) being perpendicular to said first transverse direction (Y) and said principal axis (R) being circumferential.

9. Injection device (10) according to any one of claims 1 to 5, wherein it comprises at least two radial injectors (30), each extending in a radial plane with respect to said principal axis (R), which is parallel to said longitudinal axis (X), and comprising at least two flanges (20), each of said planes extending along a second radial transverse direction (Z) perpendicular to said first circumferential transverse direction (Y) and to said principal axis (R), each of said at least two flanges (20) being radial and situated between two of said adjacent injectors (30).

10. Injection device (10) according to any one of claims 1 to 5, wherein it comprises at least two radial injectors (30), each extending in a radial plane with respect to said principal axis (R), which is radial and perpendicular to said longitudinal axis (X), and wherein it comprises at least two flanges (20), each of said planes extending in a second transverse direction (Z) parallel to said longitudinal axis (X) and perpendicular to said first transverse direction (Y), which is circumferential, each of said 14 at least two flanges (20) being radial and located between two of said adjacent injectors (30).

11. Combustion chamber (90) comprising a plurality of injection devices (10) according to any one of the preceding claims, distributed along said bottom (94) of this chamber (90).

12. Turbomachine comprising a combustion chamber (90) according to claim 11.

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