Spark plug for single-piece combustion chamber

Abstract

The invention relates to a combustion chamber for a gas turbine engine in which two openings extend through a metal wall (58) and a wall made of refractory material (16). A device (76) guides a spark plug (48) in said two openings, said guiding device comprising a metal flange (80) and a floating ring (82), said flange being shrunk onto or welded to said metal wall (58).

Description

Technical Field

[0001] The present invention relates to a combustion chamber for a gas turbine, such as an aircraft turbojet or turboprop engine, wherein a fluid (e.g., air and at least one fuel) generally flows from upstream to downstream to operate the gas turbine. Background Technology

[0002] In this text, upstream and downstream should be considered as along the axis referred to below as "first axis" or "axis X", which is the general axis of the turbine.

[0003] The upstream side is the side from which the air and fuel mixture enters the combustion chamber. "Outer" and "inner" should be understood radially relative to the first axis (X). The outer side is radially further away from this first axis than the inner side.

[0004] It can be said that such aircraft gas turbine parts are already known, which have a first shaft (X) and include:

[0005] -Outer shell (12),

[0006] -Inner housing (14), both the outer housing and the inner housing are annular and coaxial with the first axis (X), and

[0007] - A space (9) surrounding an annular combustion chamber (10) around a first axis (X), the space (9) being defined between an outer housing (12) and an inner housing (14), the annular combustion chamber comprising:

[0008] - Corresponding inner and outer annular walls, which are radially aligned with the first axis (X),

[0009] - The bottom (wall) of the annular chamber, extending between the inner annular wall and the outer annular wall, and having a first opening for passage of a device for injecting an air and fuel mixture, which is at least partially attached to the bottom of the annular chamber.

[0010] - A deflector, located downstream of the chamber bottom to thermally protect the chamber bottom, and having a second opening for the aforementioned inner and outer annular walls, defining the combustion zone of the combustion chamber.

[0011] In addition, the bottom of the chamber generally contains openings for the air (A) / fuel (C) mixture to pass through the combustion zone of the combustion chamber, with air (A) coming from the turbine compressor and fuel (C) supplied by an injector.

[0012] By definition, the chamber floor (CB) is the component described below:

[0013] - The device for injecting the air / fuel mixture is attached to the component, and

[0014] The corresponding inner and outer annular walls are attached to the component. The component is a structural bottom.

[0015] The bottom of the chamber experiences high thermal stress that can deform it. Therefore, it is common practice to protect the bottom of the chamber from heat (from the flame in the combustion zone) by means of a deflector (or a ring of deflectors) installed just downstream of the CB.

[0016] Nevertheless, gaps may occur (especially in the case of the corresponding inner and outer annular walls), which leads to problems of contamination, fuel consumption, and reignition in the chamber in the event of flameout.

[0017] In addition, it is necessary to be able to initiate the combustion of the air / fuel mixture in the combustion zone of the combustion chamber, or even to feed additional fuel to the combustion chamber downstream of the CB.

[0018] For this purpose, it is known that one of the respective inner and outer annular walls (typically the outer wall) includes at least one opening for access to a combustion chamber at one end of an energy feeding element (for a spark plug of the mixture and / or fuel injector), the other end of which may be attached to the outer housing of the chamber.

[0019] During turbine operation, the combustion chamber walls thermally expand, causing relative displacement between the blades.

[0020] To compensate for and allow for these displacements, EP-A-1770332 recommends the use of at least one guiding device, which includes the following for guiding the energy feeding element in question into a passage in the annular wall through which it passes:

[0021] - Metal flange, and

[0022] - A floating bushing, which is floatingly mounted in a flange, the floating bushing and the flange having an energy feeding element coaxially passing through it, the flange being contractively fitted or welded to the annular wall, which is typically a metal wall.

[0023] The term welding encompasses both brazing and actual welding. Summary of the Invention

[0024] In this context, the object of the present invention is to provide effective and economical solutions to at least some of the following problems and shortcomings:

[0025] - Improve the service life of the combustion chamber.

[0026] - Reduce parasitic gas leaks in areas equipped with CB.

[0027] - Reduce pollution,

[0028] - Reduce fuel consumption

[0029] - Improved ignition and reignition conditions in the combustion chamber

[0030] - Control the overall mass of the combustion chamber,

[0031] - Control the way the combustion chamber is manufactured

[0032] -Good mechanical strength,

[0033] - Improve resistance to thermal stress,

[0034] Managing the contact between metallic materials and refractory materials (such as ceramics) is, in fact, complex, as it makes attaching the energy-feeding element's guiding device (often referred to as the spark plug guide) to the refractory wall complicated.

[0035] US2013055716 definitively teaches turbine components as described above, wherein the combustion chamber includes:

[0036] -The corresponding inner annular refractory wall and outer annular refractory wall are radially aligned with the first axis (X).

[0037] - The bottom of the annular chamber, extending between the inner and outer refractory walls, has a first opening for passage of a device partially attached to the bottom of the annular chamber for injecting an air and fuel mixture.

[0038] -The corresponding first inner annular metal connecting wall and the first outer annular metal connecting wall, which are radially relative to the first axis (X), are attached to the first inner annular metal connecting wall and the first outer annular metal connecting wall respectively:

[0039] --The corresponding refractory wall, and

[0040] --Floor of the chamber,

[0041] The combustion chamber also includes:

[0042] - Two openings, each coaxially passing through the following (along an axis that intersects axis X):

[0043] --One of the first metal connecting walls, and

[0044] --One of the refractory material walls it covers, and

[0045] - A guiding device for guiding the energy feeding element into the two ports.

[0046] However, US2013055716 does not disclose that, as taught in this invention, the guiding device is attached to one of the first metal connecting walls.

[0047] By means of the present invention, the particularly excessive mechanical load on the annular refractory wall through which the port for the energy feeding element passes will be avoided, and a solution has been provided to address the problem of attaching the guiding device of the energy feeding element to the refractory wall.

[0048] It should also be noted that the deflector and the corresponding inner annular refractory wall and outer annular refractory wall are single-piece components:

[0049] - It should be possible to control the geometric tolerances of the combustion zone, especially in the event of in-flight flameout, eliminating welding operations, and maintaining the chamber volume at a relatively favorable reignition limit.

[0050] - This avoids the need for heat-resistant barrier coatings (especially those made of yttrium zirconate).

[0051] This means that the refractory material “deflector” continues to act as a deflector through the annular “bottom” (hereinafter referred to as 21) of the combustion zone that becomes the combustion chamber, protecting the metallic structural “chamber bottom” (or CB, hereinafter referred to as 20), which is itself annular and therefore not directly exposed to thermal radiation. Therefore, the term “deflector” is appropriate. The term “bottom of the single-piece assembly” has also been used below to avoid confusion with “chamber bottom or CB 20”.

[0052] Advantageously, such one-piece assemblies will be made of refractory material (i.e., based on refractory material), which may (may include) ceramic matrix composite (CMC). The wall thickness may be between 0.9 mm and 1.6 mm.

[0053] To ensure attachment of the guiding device, it is preferable that the guiding device includes a metal flange and a floating bushing mounted buoyantly in the flange, the floating bushing and the flange being adapted to allow an energy feeding element to pass coaxially therethrough, the flange being attached to one of the first metal connecting walls.

[0054] To still ensure this attachment, it is advantageous for the guide device (flange, if provided) to be attached to one of the first metal connecting walls by means of a shrink fit or by welding.

[0055] Furthermore, the advantages are:

[0056] The combustion chamber will also include a refractory deflector, which is (axially) positioned downstream of the chamber floor for thermal protection, and has a second opening for the passage of the fuel injection device.

[0057] - The deflector and the refractory wall can be formed as a single-piece assembly.

[0058] Furthermore, to further ensure the attachment of the guiding device without significantly stressing the refractory wall, an intermediate attachment bushing is also specified:

[0059] - An intermediate attachment bushing is attached, preferably with a shrink fit or by welding, to the flange and the first annular metal connecting wall, wherein the energy feeding element in question passes through the first annular metal connecting wall, and

[0060] - The intermediate attachment bushing itself will have an energy feeding element that passes through it.

[0061] By inserting such an intermediate bushing, a priori promotion will be made for the integral mounting of the guide device between this flange and the first connecting wall (also a metal wall) of a flange-like metal bushing.

[0062] Furthermore, for the same purpose as above, it is even stipulated that:

[0063] - The flange has a shank (also referred to as a narrow aperture) that is parallel to the axis of the two coaxial ports and engages in the aperture of the first metal connecting wall through which the energy feeding element passes.

[0064] - The attachment bushing is fitted into or welded to the wall and the handle by being inserted between them in such a way that it is either inserted into the wall and the handle.

[0065] It is also specified that the shank of the flange, parallel to the two openings, is interrupted at a distance from the annular refractory wall through which the shank passes and faces.

[0066] Furthermore, in order to facilitate flange installation and to limit the mechanical weakening of the refractory wall as much as possible, it is stipulated that, of the two openings, the diameter of the opening through the first metal connecting wall under discussion is larger than the diameter of the opening coaxially through the refractory wall located at the opposite location.

[0067] In other words, the opening in one of the first metal connecting walls will advantageously have a larger diameter (D2) than the diameter (D1) of the opening in one of the annular refractory walls.

[0068] To limit interference between the attached bushing and the refractory wall, it is also specified that:

[0069] - The attachment bushing has an inner diameter (D1), an outer diameter (D2), and a thickness (e) between the inner diameter (D1) and the outer diameter (D2), and

[0070] - The diameter difference between the two openings is greater than the thickness (e) of the attached bushing.

[0071] Therefore, the attachment bushing will not protrude into the space reserved for the possible gap of the energy feeding element.

[0072] In addition, in order to position the flange in the best possible way and to facilitate its installation, it is stipulated that the height (H1) of the attached bushing on the shaft parallel to the two ports is greater than the height of the handle, so as to avoid possible contact between the metal material and the refractory material (ceramic).

[0073] The height (H1) of the attachment bushing may also be greater than the thickness of the first metal connecting wall, so that the attachment bushing is attached to the first metal connecting wall and the first metal connecting wall surrounds the attachment bushing adjacently.

[0074] Constructed in this way, preferably radially outward above this first metal connecting wall, the bushing can particularly serve as a support for the guide device used to mount the energy feeding element in question.

[0075] In this regard, it is even stipulated that, in operation, the shank of the flange is supported by the attached bushing via a flare present on the flange.

[0076] In addition, for the purpose of supporting and / or controlling the clearance of the energy feeding element in its guiding device, it is also specified that:

[0077] - The floating bushing has an outer edge that is laterally guided into an inner annular groove in the flange.

[0078] - The flange shank expands to define the bottom of the groove and extends peripherally to the flange edge, where a cup-shaped element is attached, such that the edge of the floating bushing is guided between the bottom and the cup-shaped element, and

[0079] - The flared end of the flange shank is located outside the attachment bushing.

[0080] On the other hand, it relates to the mechanical strength of the first metal connecting wall and the connection between this wall and the refractory wall it covers, the refractory wall itself having the energy feeding element discussed therethrough.

[0081] For this purpose, it is stipulated that a first covering tab is formed along the annular refractory wall of the covering, through the opening in the first metal connecting wall, the first covering tab protruding relative to the second covering tab:

[0082] - The second cover tab protrudes again relative to the part of the first metal connecting wall that extends circumferentially around the first shaft (X), and

[0083] -In this case, on either side of the first covering tab, the attachment pin attaches the first metal connecting wall and the annular refractory wall it covers to each other by passing through the first covering tab.

[0084] Generally speaking, the following should be expected from the above:

[0085] - Reduction in cost and overall quality,

[0086] -And better control over the geometric tolerances of the combustion zone.

[0087] In addition to the combustion chamber described above, the present invention also relates to an aircraft gas turbine equipped with such combustion chamber. Attached Figure Description

[0088] When necessary, the invention will be better understood by reading the following description, given by way of non-limiting examples, with reference to the accompanying drawings, in which other details, features, and advantages of the invention will become apparent, wherein:

[0089] -[ Figure 1 [This is a schematic half-view of an axial cross-section (axis X) of a turbine "combustion module" including a combustion chamber according to the present invention.]

[0090] -[ Figure 2 ] is with Figure 1 The view is the same as the view in the image, but it is offset at an angle around the X-axis and the individual combustion chambers.

[0091] -[ Figure 3 ]yes Figure 2 Detail III,

[0092] -[ Figure 4 ]yes Figure 1 Detail IV,

[0093] -[ Figure 5 ]exhibit Figure 4 The area prior to the installation of the energy feed element and its guiding device.

[0094] -[ Figure 6 Showing a partial horizontal magnified view Figure 5 The area in the middle,

[0095] -[ Figure 7 This refers to the guiding device after the installation of the energy feeding element. Figure 6 The same view as the view, and

[0096] -[ Figure 8 ] is as follows Figure 5 However, this is a view after the guiding device and energy feeding element have been installed in itself. Detailed Implementation

[0097] exist Figure 1 In one embodiment, part 1 of the aircraft turbine has a space 9 surrounding an annular combustion chamber 10 and receiving an airflow A, which at least partially supplies the combustion zone 11 of the chamber 10. The space 9 is defined between an outer casing 12 and an inner casing 14, both of which are annular and coaxial with the turbine's axis X.

[0098] In space 9, turbine component 1 includes compressor 3, which may be a high-pressure compressor axially arranged after a low-pressure compressor. Its downstream portion (visible in the figure) includes a centrifugal stage 5 and an annular diffuser 7 connected downstream of compressor 3. Diffuser 7 opens into space 9.

[0099] The component 1, together with the outer housing 12 and the inner housing 14, may be referred to as the "combustion module".

[0100] Compressed air (A) from compressor 3 is introduced into combustion chamber 10, where it is mixed with air from injector (e.g.) Figure 2 The fuel (C) is mixed with the injector 4) in the chamber. The combustion gas is directed toward the turbine (here, the high-pressure turbine) located downstream of the outlet (DO) of the chamber 10, and first toward the distributor 23, which is part of the turbine stator.

[0101] The chamber 10 includes an annular outer wall 16 and an annular inner wall 18, both of which are made of refractory material.

[0102] As understood, the outer shell 12, the inner shell 14, the space 9, the outer wall 16, and the inner wall 18 each form a ring around the first axis X.

[0103] Therefore, the outer wall 16 and the inner wall 18 are not annular around each axis I-I' that defines the axis for injecting fuel into each injector 4 in the combustion chamber 10.

[0104] An annular outer wall 16 and an annular inner wall 18 are connected upstream to a bottom 21, which itself is annular around a first axis X.

[0105] The bottom 21 forms the bottom of the combustion zone 11.

[0106] Combustion chamber 10 is in the following state:

[0107] - It is held on the upstream side by the main shaft 42 attached to the outer housing 12 and the walls attached to the walls shown below as 58, 60 and / or the main shaft attached to the CB 20, and

[0108] - It is held on the downstream side by the attachment flange.

[0109] Chamber 10 is axially supported at its downstream end by the outer and inner annular shells of a distributor (here, a high-pressure distributor 23) via sealing sheets 220 and 240, respectively, connected to the outer and inner annular flanges 22 and 24. These flanges are axially supported by axial pins 221 and 241, respectively, which are provided on the outer annular shell 247 and inner annular shell 249. As can be accomplished externally by the outer annular flange, the radially inner annular flange 24 extends radially inward relative to the sealing sheet 240 to an annular support member 245 in the form of a stud that opens downstream. This annular support member is supported by a housing 25, referred to as the HP distributor support housing. A generally radial blade 251 extends between the outer and inner annular shells of the distributor 23, which is otherwise attached.

[0110] Furthermore, the inner shell 14 extending along the chamber 10 can be considered to be defined by, or include, the diffuser shell 26 and the inner intermediate slats 28 attached upstream of the shell 26 and downstream of the shell 25.

[0111] In the upstream section (UP), the combustion chamber 10 may be attached by at least three attachment shafts 42 distributed circumferentially around the shaft X, which are in particular the shafts around which the movable blades of the turbine and compressor rotate.

[0112] Based on the specific characteristics of the combustion chamber 10 described herein, the outer annular wall 16, the inner annular wall 18, and the annular bottom 21 (of the combustion zone 11) that form the deflector define a one-piece refractory assembly 100.

[0113] Just upstream of the bottom 21 of the combustion zone is the bottom 20 of the annular metal chamber, to which a device 2 for injecting an air and fuel mixture (hereinafter referred to as injection device 2) is attached and distributed circumferentially around axis X.

[0114] This attachment can be accomplished by direct attachment (clamping) of the bowl-shaped object 6 provided on the injection device 2.

[0115] Each injection device 2 may therefore include a bowl-shaped part 6, which includes a venturi tube 60a and terminates with a diverging portion 60b toward the combustion zone 11 for ejecting a jet of the received air and fuel mixture.

[0116] exist Figure 2After examining the cross-section, and shifting circumferentially along the axis passing through one of the injection devices 2, it can be seen that the combustion chamber 10 thus includes such an injection device 2, which (at least for the bowl-shaped object 6) passes through a first passage opening 43 formed in the chamber bottom 20 and then coaxially passes through a second passage opening 45 formed through the bottom 21 of the combustion zone, while the injection device 2 (the bowl-shaped object 6) is not directly attached to the bottom 21.

[0117] The bowl-shaped structure 6, the fuel outlet therein, and the first opening 43 and the second opening 45 are coaxially centered on axis I-I', which is parallel to axis X1. The one-piece outer annular wall 16 and the inner annular refractory wall 18 extend generally parallel to axis X1.

[0118] The intermediate space 56 separates CB 20 and the bottom of the combustion zone 21 along this axis I-I'.

[0119] The bowl-shaped object 6 is tightly mounted (attached) in the coaxial sleeve 13, which is located in the opening 43 and is itself attached to the CB 20. An axial clearance J is maintained between each sleeve 13 and the bottom 21 of the combustion chamber. In this way, contact with fragile refractory materials and metals is avoided.

[0120] Fuel injector 4 is installed in the inlet channel 6a of the bowl-shaped part 6 of each injection device 2, and the outlet of the injector (similar to channel 6a) is oriented along the corresponding axis I-I'.

[0121] Around its inlet channel 6a, the bowl-shaped object also has one or more air inlet rotating components 15 passing through it.

[0122] The peripheral rotating component 15 allows a portion of the air A received from space 9 to be introduced into the bowl 6 (a priori toward the venturi 60a) and has rotational movement (arrow 15a).

[0123] An annular cover 40 may also be provided, having an opening 41 therethrough, which allows the injector 4 and air A to pass toward the bowl-shaped object 6. The openings 41 may each be coaxial with a so-called axis I-I'.

[0124] In order to supply air A to the combustion zone 11 via annular volumes 160 and 180, the annular volumes are respectively located at the following positions:

[0125] - Between the outer wall 16 and the outer shell 12, and

[0126] - Between the inner wall 18 and the inner shell 14

[0127] The parts forming the inner wall 18 and / or outer wall 16 of the single-piece assembly 100 may additionally have main holes 44 and / or dilution holes 46 passing through them, which lead to the combustion zone 11. Several multi-perforated through-holes 47" for injecting cooling air into the combustion zone have also been shown in detail. If they are present, they extend over a much larger surface area, as is known.

[0128] For a connection with controlled (mechanical / thermal) stress and manufacturing requirements between the single-piece assembly 100 and the surrounding metal parts of the turbine (if they exist: main shaft 42, sheets 220, 240…), the following is specified:

[0129] - Towards the upstream end of the combustion chamber 10, the first inner annular metal connecting wall 60 and the first outer annular metal connecting wall 58 can respectively connect the CB 20 to the inner wall 18 and the outer wall 16, or even connect the shroud 40 located upstream of this CB, and / or

[0130] - Towards the downstream end of the chamber, a second internal metal connecting wall 64 and a second external metal connecting wall 62, each having an internal flange 24 and an external flange 22, are provided for connection between the following:

[0131] --Between the inner wall 18 and the metal strain gauge (e.g., injector housing 25), and

[0132] --Between the outer wall 16 and the portion of the DHP (outer annular shell 247) and / or the outer shell 12.

[0133] When the turbine is operating, the connecting metal walls 58, 60, 62, and 64 will be flexible sheets, which are more deformable than the refractory material of assembly 10.

[0134] Furthermore, for these metal / refractory material connection problems, a connection is provided between the inner wall 18 and the outer wall 16, and the inner 60, 64 and outer 58, 62 of the metal walls are respectively connected by pins 66 and washers 68 that are attached (e.g., welded) together and pass through holes provided in the respective walls.

[0135] In contrast, the connection between the (metal) CB 20 and the corresponding (or even the metal cover 40) connecting wall’s first metal interior 60 and exterior 58 will preferably be secured a priori by a plurality of screw-nut assemblies 70 passing through it.

[0136] In addition, at least one additional passageway, with dual ports 72 and 74, coaxially passes through the following:

[0137] - One of the corresponding first inner annular metal connecting wall 60 and the first outer annular metal connecting wall 58 (port 72), and the opposite

[0138] - One of the corresponding inner annular refractory wall 18 and outer annular refractory wall 16 (opening 74),

[0139] An energy feeding element 48 may be placed therein, which may typically include a spark plug or a fuel injector.

[0140] The free end 48a of the energy feeding element 48 is flush with the inner surface of the associated refractory wall (16 in this example) to communicate with the combustion zone 11. Figure 4 .

[0141] For easier installation, wall 58 will cover wall 16 and wall 60 will cover wall 18, as particularly in Figure 4 The walls 58 seen in and subsequently used for facing wall 16, in this example, allow the element 48 to pass through it generally along a common axis 75 that intersects the axis X and is perpendicular to the axis X1.

[0142] In the following text, we will consider, for example, element 48 as a spark plug, which leads to the combustion zone 11 through its inner end.

[0143] In practice, the air-fuel mixture injected into the combustion chamber 11 will be ignited by means of at least one spark plug (e.g., spark plug 48) that can extend radially to the shaft X1 outside the chamber.

[0144] The radially outer end of spark plug 48 may be attached to the outer housing 12, and the spark plug is connected to the power supply component (not shown) outside the outer housing.

[0145] At its radial inner end (therefore relative to axis X1 or I-I'; see Figure 4 Spark plug 48 is guided to ports 72 and 74.

[0146] For this purpose, the guide device 76 is attached to the metal wall 58 outside the chamber 10, surrounding the opening 72, to compensate for the relative displacement between the chamber wall and the spark plug 48 during turbine operation. These relative displacements occur primarily in the longitudinal direction, generally parallel to the shaft X1; see also... Figure 4 Arrow 78 in the middle.

[0147] The guiding device 78 is a priori a metallic device. It includes a flange 80 and a bushing 82 that is floatingly mounted in the flange 80 to allow displacement of the spark plug 48 generally parallel to the axis I-I', the bushing being held / secured by the neck 820 of the floating bushing.

[0148] The floating bushing 82 and flange 80 have a spark plug 48 that passes through them coaxially (shaft 75).

[0149] To avoid interfering with the refractory walls 16 and 18, the flange 80 is contracted or welded to (in this example) the external metal connecting wall 58.

[0150] To facilitate and secure this attachment, it is preferable to use an intermediate attachment bushing 84, which may be a metal bushing that shrinks in or is welded to the flange 80 and the metal connecting wall; in the example, the outer wall 58 (see...) Figure 6 ).

[0151] Therefore, the intermediate attachment bushing 84 is tightly fitted into the opening 72. It can be supported by the wall 16 and surrounds the opening 74.

[0152] The floating bushing 82 has an outer edge 830 that moves freely laterally relative to the shaft 75 (generally parallel to the shaft I-I') in the inner annular groove 88 of the flange 80.

[0153] The neck 820 is located at the junction between the central region of the edge 830 and the central region of the possible truncated conical part 835 for guiding the initial axial engagement of the element 48 into the floating bushing 82.

[0154] The flange 80 may have a shank or aperture 86 through which it is attached to the metal wall 58, preferably through an intermediate attachment bushing 84 (by brazing, preferably by the attachment of a welded shank / bushel).

[0155] To form the groove 88, the flange shank 84:

[0156] - (via shoulder) expansion to define the bottom 840 of the groove 88, and

[0157] - Extending peripherally to the flange edge 860, the cup 90 is attached (a priori brazed or welded) to the flange edge, such that the edge 830 of the floating bushing can be guided into the groove 88 between the bottom 840 and the cup 90.

[0158] The flared end of the flange shank (i.e., bottom 840) is located outside the attached bushing 84: along the shaft 75, beyond the free end of the bushing 84 on which the bottom 840 rests.

[0159] The handle 86 can be cylindrical.

[0160] For secure location tracking, the following regulations apply:

[0161] - Parallel to the axis of element 48 and the two openings 72, 74, the shank 86 of flange 80 is interrupted at a distance from the refractory wall in question: the free end of the shank and the space 92 between the facing wall 16 in this case; and / or

[0162] - The diameter D1 of the opening 72 through the (first) metal connecting wall (58 in the example) is greater than the diameter D2 of the opening 74 coaxially through the facing refractory wall (16 in the example); see also Figure 6 Therefore, there is a support member 94 ( Figure 5 During positioning prior to attachment to wall 58, the attachment bushing 84 is pushed on the support.

[0163] In addition, it may be necessary to restrict the protrusions in flange 80 to openings 72, 74. For this purpose, the following is specified:

[0164] - The attachment bushing 84 has an inner diameter, an outer diameter, and a thickness e1 between the inner diameter and the outer diameter. Figure 6 ),and

[0165] -The two ports 72 and 74 (by...) Figure 5 The diameter difference between the shoulder formed by the edge 94 is greater than the thickness (e) of the attached bushing 84: see Figure 6 .

[0166] Furthermore, to facilitate the installation of flange 80, it is further specified that the height (H1) of the attachment bushing 84, parallel to the two openings 72 and 74, is greater than the corresponding (first) metal connecting wall (58 in the example; see also...). Figure 6 The thickness e2.

[0167] In this manner, it can be specified that the flared end (bottom 520) of the flange shank 86 is supported by the attachment bushing 84 along the shaft 75; see also Figure 4 or Figure 7 .

[0168] The mechanical strength problem related to the presence of the single-piece assembly 100 has also arisen regarding the mechanical weakening caused by the opening 72 in the relevant metal connecting wall 58 provided in the example.

[0169] To overcome this problem, it is specified that the opening 72 is formed in the first covering tab 96 along the covered annular refractory wall (wall 16 in this example), the first covering tab protruding downstream relative to the second covering tab 98:

[0170] - The second cover tab protrudes again relative to the part 102 of the first metal connecting wall (58 in the example) that extends circumferentially around the first axis X, and

[0171] -In this embodiment, on either side of the first covering tab 96, an attachment pin 66 (held by a washer 68) passes through and attaches to the first metal connecting wall (58 in the example) and the annular refractory wall (16 in the example) that it covers.

[0172] This characteristic can be of great importance.

[0173] Therefore, it may be advantageous to make the first covering tab 96 (the protrusion formed therefrom):

[0174] -A guiding device that is only available locally to enable attachment of energy delivery elements (spark plug guides).

[0175] -And therefore does not extend continuously over the entire circumference.

[0176] Therefore, it reduces issues related to weight, friction, and thermal expansion.

[0177] Advantageously, the first metal connecting wall (58 in this example) will therefore extend axially in the following locations:

[0178] - Extending axially along the first length X10, around most of its periphery around axis X.

[0179] -Extends locally along the second length X20 axially to enable attachment (in the form of a tab: second covering tab 98), and

[0180] - Extending axially along the third length X30, or even more locally (also in the form of a tab: the first covering tab 96) to allow for the attachment of a guide device for the energy feeding element.

[0181] Such biaxially protruding areas of the first metal connecting wall can be defined as follows:

[0182] Axial (X20+X30): Between 1.2×D2 and 3×D2 (D2: diameter of the 74-hole opening),

[0183] Along the circumference (cumulative length C1 of the first covering tab 96 and the second covering tab 98): between 6×D2 and 12×D2; see also Figure 8 .

[0184] With such embodiments, weight and friction will be significantly reduced without affecting mechanical strength.

[0185] As understood, in order to house the energy feeding element 48 in question, it will be possible to locally, downstream, extend the fully circumferential part 102 through which the mounting port 72 will pass:

[0186] - First, extending to the second (almost a considerable length along the circumference) covering protrusion 98,

[0187] -This then extends to the first covering tab 96 (shorter along the circumference, preferably just around the opening 72) and is circumferentially centered along the second covering tab 98; see also Figure 5 or Figure 8 .

[0188] It should be noted that the first cover tab 96 and the second cover tab 98 may be defined on a portion of a cylindrical shaft parallel to axis X1.

Claims

1. An aircraft gas turbine component having a first shaft (X) and including an outer housing (12), an inner housing (14), and a space (9) surrounding an annular combustion chamber (10) around the first shaft (X), said outer housing and said inner housing being annular and coaxial with the first shaft (X), said space (9) being defined between said outer housing (12) and said inner housing (14), said combustion chamber comprising: -The corresponding inner annular refractory wall and outer annular refractory wall are radially aligned with the first axis (X). - The bottom of the annular chamber (20), which extends between the inner annular refractory wall and the outer annular refractory wall, and has a first opening (43) for allowing passage of a device (2) for injecting an air and fuel mixture, which is partially attached to the bottom of the annular chamber (20). - A first metal connecting wall, which is composed of a first inner annular metal connecting wall and a first outer annular metal connecting wall, is radially arranged relative to the first axis (X), and the following are attached to the first inner annular metal connecting wall and the first outer annular metal connecting wall: --The corresponding refractory wall, and --The bottom of the annular chamber (20). - Two openings, each coaxially passing through the following: --One of the first metal connecting walls, and --One of the refractory material walls it covers, and -Guiding device (76), which is used to guide the energy feeding element (48) into the two ports, The combustion chamber is characterized in that the guiding device (76) is attached to one of the first metal connecting walls. Wherein, along the refractory wall of the covering, the opening through the first metal connecting wall is formed in the first covering tab (96), the first covering tab protruding relative to the second covering tab (98): - The second cover tab protrudes again relative to the part (102) of the first metal connecting wall that extends circumferentially around the first shaft (X), and -In this case, on either side of the first covering tab (96), the attachment pins (66, 68) attach the first metal connecting wall and the refractory wall covered by the first covering tab to each other by passing through the first covering tab.

2. The gas turbine component according to claim 1, characterized in that, For the attachment, the guiding device includes a metal flange (80) and a floating bushing (82) floatingly mounted in the flange (80), the floating bushing and the flange being adapted to allow the energy feeding element (48) to pass coaxially (75) through the floating bushing and the flange, the flange being attached to one of the first metal connecting walls.

3. The gas turbine component according to claim 1, characterized in that, For its attachment, the attached guide device (76) is contractively fitted or welded to one of the first metal connecting walls.

4. The gas turbine component according to claim 2, characterized in that, It also includes an intermediate attachment bushing (84) for attaching the flange (80): - The intermediate attachment bushing is attached to the flange (80) and to one of the first metal connecting walls.

5. The gas turbine component according to claim 4, characterized in that: - The flange (80) has a shank (86) parallel to the axis of the two openings and engaging in the opening of one of the first metal connecting walls, and - The intermediate attachment bushing (84) is inserted between the first metal connecting wall and the handle (86) and is either contractively fitted or welded to them.

6. The gas turbine component according to claim 5, characterized in that, The shaft (75) parallel to the two openings, the shank (86) of the flange (80) is interrupted at a distance from one of the refractory walls it faces.

7. The gas turbine part according to any one of claims 1 to 6, characterized in that, The diameter of the opening in one of the first metal connecting walls is larger than the diameter of the opening in one of the refractory material walls.

8. The gas turbine part according to any one of claims 4 to 6, characterized in that: -The intermediate attachment bushing (84) has an inner diameter, an outer diameter, and a thickness (e1) between the inner diameter and the outer diameter, and - The difference in diameter (D1, D2) between the two openings is greater than the thickness (e1) of the intermediate attachment bushing (84).

9. The gas turbine part according to claim 5, characterized in that, The height (H1) of the intermediate attachment bushing (84) is greater than the height of the handle (86) of the shaft (75) parallel to the two openings.

10. The gas turbine component according to claim 5, characterized in that: - The floating bushing (82) has an outer edge (830) that is laterally guided into an inner annular groove (88) of the flange. - The flared end (840) of the handle of the flange (80) defines the bottom of the groove and extends peripherally to the flange edge (860), where a cup (90) is attached, such that the outer edge (830) of the floating bushing is guided between the bottom and the cup, and - The flare (840) of the shank (86) of the flange is located outside the intermediate attachment bushing (84).

11. The gas turbine component according to claim 10, characterized in that, The flare (840) of the handle of the flange (80) is supported by the intermediate attachment bushing (84).

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