MODULE FOR AN AIRCRAFT TURBOMACHINE

Abstract

Module (10) for an aircraft turbomachine, this module (10) comprising: - a rotor including a centrifugal compressor wheel (20) (12) and a turbine wheel (22) (16), - a rectifier-diffuser (26) mounted at the outlet of the wheel (20), - a turbine distributor (28) mounted upstream of the wheel (22), - an annular combustion chamber (14) interposed axially between the rectifier-diffuser (26) and the distributor (28), - a ventilation air injector (56) surrounded by the combustion chamber (14), and - a sheet metal arrangement (32) connecting the rectifier-diffuser (26) to the distributor (28) and to the injector (56), this sheet metal arrangement (32) being formed in one piece with said injector (56) which is configured to ventilate said distributor (28). Figure for the abbreviation: Figure 1

Description

Title of the invention: MODULE FOR AN AIRCRAFT TURBOMACHINE Technical field of the invention

[0001] The present invention relates to a module for an aircraft turbomachine, as well as a turbomachine comprising such a module. Technical background

[0002] The state of the art includes in particular document FR-A-2 937 371, FR-A1-2 904 038, FR-A1-2 975 733, FR-A1-2 904 034 and FR-A1-2 904 036.

[0003] An aircraft turbomachine includes a gas generator which conventionally comprises, from upstream to downstream, with reference to the flow of gases in the turbomachine, at least one compressor, an annular combustion chamber and at least one turbine.

[0004] In the case of a twin-spool turbofan engine, with low-pressure and high-pressure components respectively, the gas generator comprises successively a low-pressure compressor, a high-pressure compressor, the combustion chamber, a high-pressure turbine, and a low-pressure turbine. The gas generator defines a first annular flow path of gas, called the primary flow, which passes through the compressors, the combustion chamber, and the turbines.

[0005] The rotor of the high-pressure compressor is connected to the rotor of the high-pressure turbine by a high-pressure shaft. The rotor of the low-pressure compressor is connected to the rotor of the low-pressure turbine by a low-pressure shaft which passes through the high-pressure shaft and drives a shaft of a propulsion propeller generally located upstream of the gas generator.

[0006] When this propeller is enclosed and therefore surrounded by an annular casing, this propeller is called a blower and generates an airflow, called a secondary flow, which flows around the gas generator.

[0007] Axial compressors and centrifugal compressors exist, and the present application relates to a module and a turbomachine comprising a centrifugal compressor. The distinctive feature of the centrifugal compressor is that its rotor is formed by an impeller which includes an axially oriented inlet and an outwardly radially oriented outlet.

[0008] In a module or turbomachine, the impeller is connected to a turbine wheel by a shaft.

[0009] The combustion chamber is axially interposed between the centrifugal compressor and the turbine wheel and is supplied with air by an outlet-mounted rectifier-diffuser of the spinning wheel and which allows the air to be straightened before being diffused with an axial component.

[0010] During operation, the turbine wheel is subjected to significant thermal stresses and must be ventilated. It is therefore known to draw compressed air upstream of the chamber to ventilate the turbine wheel.

[0011] In particular, it is known to provide a ventilation air injector which is surrounded by the chamber and which includes an air outlet oriented axially downstream in order to ventilate the turbine wheel.

[0012] The applicant has already proposed in the aforementioned documents solutions for guiding the air exiting the compressor or the rectifier-diffuser in the annular space contained between the combustion chamber and the impeller shaft connecting to the turbine wheel, particularly to supply the injector. These solutions employ a sheet metal arrangement that connects the rectifier-diffuser to the distributor as well as to the turbine wheel ventilation injector.

[0013] In document FR-A1-2 904 036, for example, [Fig. 4] shows a lamination arrangement that guides a portion of the air exiting the rectifier-diffuser so that this air flows radially from the inside to the outside along a downstream radial face of the impeller. This air is then injected downstream of the chamber. The lamination arrangement also guides another portion of the air exiting the chamber towards the turbine wheel ventilation injector.

[0014] However, it would also be desirable to find a solution for ventilating the distributor which is subjected in operation to temperatures as high as those of the turbine wheel.

[0015] The invention proposes an improvement to this technology which provides a solution to this problem, which is simple, effective and economical. Summary of the invention

[0016] The invention relates to a module for an aircraft turbomachine, this module comprising:

[0017] - a rotor comprising a centrifugal compressor impeller and a movable impeller turbine, the impeller and the rotating wheel being connected to each other by a rotating shaft that pivots around an axis,

[0018] - a stator comprising a rectifier-diffuser mounted at the output of the wheel and a turbine distributor mounted upstream of the rotating wheel,

[0019] - an annular combustion chamber also forming part of the stator and axially interposed between the rectifier-diffuser and the distributor, the combustion chamber comprises two coaxial annular walls, respectively internal and external, which are connected upstream by an annular chamber bottom,

[0020] - at least one ventilation air injector also forming part of the stator, said injector being surrounded by the combustion chamber and

[0021] - an arrangement of connecting sheets from the rectifier-diffuser to the distributor and to The injector, this arrangement of sheet metal which is also part of the stator and comprises:

[0022] + a first annular sheet or portion of annular sheet which is surrounded by said internal wall of the chamber and which defines with this internal wall a first annular duct for the passage of air exiting the rectifier-diffuser, the air being intended to flow from upstream to downstream in this first duct,

[0023] + a second annular sheet or portion of annular sheet which surrounds said shaft and which, with this tree, defines a second annular air passage duct, this second duct being supplied with air by the first duct, and the air being intended to flow from downstream to upstream in this second duct, and

[0024] + a third annular sheet or portion of annular sheet which is located, from a just preference, downstream of the wheel and extending radially from the inside to the outside from the second sheet or portion of sheet to the outlet of the wheel, this third sheet or portion of sheet defining with a radial face downstream of the wheel a third annular air passage duct which is supplied with air by the second duct, the air being intended to flow radially from the inside to the outside in this third duct,

[0025] characterized in that the sheet metal arrangement is formed in one piece with said at least one injector which has at least one air outlet which opens towards said distributor, and the sheet metal arrangement includes openings for the sampling of air in the third conduit and the supplying of said injector with this sampling air.

[0026] The air exiting the rectifier-diffuser has been compressed in the centrifugal compressor and is at a relatively high pressure. Some of this air is guided by the lamination arrangement and flows radially from the inside to the outside along the downstream radial face of the impeller. This flow causes recompression of the air by vortex effect between the downstream radial face of the impeller and the lamination arrangement. Compressed air at a pressure higher than that exiting the rectifier-diffuser is therefore found at the impeller outlet. According to the invention, the lamination arrangement is designed to convey this air to the injector, which is configured to ventilate the distributor and not the turbine wheel. To this end, the lamination arrangement includes openings for drawing in this air and supplying it to the injector.The distributor is thus ventilated with compressed air at a higher pressure than the air exiting the rectifier-diffuser, which is particularly advantageous as it significantly improves the efficiency of this ventilation. Although the temperature of the compressed air exiting the rectifier-diffuser can also increase due to viscous friction with the impeller as the air flows along it. On the downstream radial face, the compressed air will have time to recover its initial temperature (at the outlet of the rectifier-diffuser) before reaching the injector due to its passage through the arrangement of sheets which is generally at the temperature of the air exiting the rectifier-diffuser.

[0027] The sheet metal arrangement can be an arrangement of one or more sheet(s) or of one or more portion(s) of sheet metal.

[0028] The module according to the invention may comprise one or more of the following features, taken individually or in combination with each other: - the sheet metal arrangement includes at least one first opening upstream for the extraction of air from the third duct, and at least one second opening downstream for supplying said at least one injector with this extracted air; - said at least a first opening is formed by an annular row of orifices which is located at the level of the external periphery of the wheel, and said at least a second opening is formed by another annular row of orifices which is preferably formed in said first annular sheet or portion of sheet; - the arrangement of sheets forms an internal annular cavity which is radially interposed between the shaft and the combustion chamber and which includes an air inlet formed by said at least a first opening, and an air outlet formed by said at least a second opening; - the arrangement of sheets delimits an internal annular cavity which is interposed radially between the shaft and the combustion chamber, the first sheet or portion of sheet comprising a double annular skin which extends from said at least a first opening to said at least a second opening and which defines at least one air circulation channel from said at least a first opening to said at least a second opening;

[0029] — the first sheet or portion of sheet comprises a double annular skin which extends from said at least one first opening until said at least one second opening;

[0030] — the double annular skin defines said at least one channel; - said at least one injector is axially projecting downstream from a sheet or portion of sheet of the sheet arrangement, such as said first sheet or portion of sheet;

[0031] — said at least one injector comprises an annular row of nozzles;

[0032] each injector is formed by a nozzle which extends along a longitudinal extension direction; - each of the nozzles has a general rectilinear orientation or shape; - each of the nozzles extends from upstream to downstream and radially outwards or parallel to said axis; - the sheet metal arrangement includes an annular flange for fixing to an annular flange, called the first flange, integral with said distributor, said at least one injector being located radially outside this flange;

[0033] — said at least one injector surrounds the flange;

[0034] the flange is crossed radially by lunules or openings for the fluidic communication of said first conduit with said second conduit;

[0035] — the lunules or lights are oriented radially;

[0036] — the flange is devoid of axial air passage orifices;

[0037] - said at least one injector passes through the openings of an internal annular rim of the combustion chamber, this internal annular rim being connected by its external periphery to a downstream end of said internal annular wall of the chamber;

[0038] - said at least one outlet of said at least one injector is oriented to unblock radially outwards;

[0039] - said distributor comprises two annular ferrules, respectively internal and external, between which extend the vanes,

[0040] - the distributor includes a foot which extends radially inwards at starting from the inner ferrule;

[0041] — said at least one outlet of said at least one injector is oriented towards the ferrule internal annular and in particular an internal annular face of this internal annular ferrule;

[0042] - said at least one outlet of said at least one injector is oriented to unblock towards the inner ferrule and / or to open towards the base of the distributor;

[0043] - said internal annular rim has its internal periphery which is radially supported on a connecting wall fixed or connected to the base of the dispenser;

[0044] — said connecting wall is annular;

[0045] - said at least one injector opens at the level of said connecting wall, and in particular of the outer periphery of this connecting wall;

[0046] — the connecting wall, and in particular its inner periphery, is fixed or connected to the bridles;

[0047] — the connecting wall, and in particular its outer periphery, is secured to the foot of the distributor by at least one pin oriented axially and passing for example through holes in the connecting wall and the foot, or even also through the external periphery of the first flange;

[0048] - said at least one injector is, preferably at least partially, intercalated radially between said first flange and said internal annular ferrule of the distributor;

[0049] — the third annular sheet or portion of annular sheet is located opposite the spinning wheel.

[0050] The present invention also relates to an aircraft turbomachine, comprising at least one module as described above. Brief description of the figures

[0051] Other features and advantages of the invention will become apparent upon reading the detailed description that follows, for an understanding of which reference should be made to the accompanying drawings in which:

[0052] [Fig-1] [Fig.1] is a schematic half-view in axial section of a module according the invention for an aircraft turbomachine,

[0053] [Fig.2] [Fig.2] is a larger scale view of part of [Fig.1],

[0054] [Fig.3] [Fig.3] is another larger-scale view of part of [Fig.1],

[0055] [Fig.4] [Fig.4] is another view similar to that of [Fig.1] and which illustrates a variant embodiment of the invention,

[0056] [Fig. 5] [Fig. 5] is a larger-scale view of part of [Fig. 4], and

[0057] [Fig.6] [Fig.6] is another larger-scale view of part of [Fig.4]. Detailed description of the invention

[0058] Fig. 1 shows a module 10 for an aircraft turbomachine, this turbomachine being here a twin-spool turbojet engine although this example is not limiting.

[0059] Axis A designates the longitudinal axis of the turbomachine.

[0060] The turbomachine is partially represented and includes a gas generator which comprises, from upstream to downstream with reference to the flow of gases along axis A, at least one compressor 12, an annular combustion chamber 14 and at least one turbine 16.

[0061] The turbomachine may include a low-pressure compressor (not shown) followed by a high-pressure centrifugal compressor (shown), and the turbine may also include a high-pressure turbine (shown) followed by a low-pressure turbine (not shown).

[0062] The compressor rotor (centrifugal) 12 is connected to the turbine rotor (high pressure) 16 by a shaft (high pressure) 18. The shaft 18 is movable in rotation around the axis A.

[0063] The compressor rotor 12 is formed by a wheel 20. The turbine rotor 16 is formed by a wheel 22. The shaft 18 connects the wheel 20 and the wheel 22 and forms with them a rotor or rotating body, in particular high pressure.

[0064] The combustion chamber 14 comprises two coaxial annular walls, respectively internal 14a and external 14b, which are connected upstream by an annular chamber bottom 14c.

[0065] In a known manner, the bottom of chamber 14c is equipped with fuel injection systems 24 into the combustion chamber 14.

[0066] Module 10 includes several other stator elements including in particular a rectifier-diffuser 26 and a distributor 28 of the turbine 16.

[0067] The rectifier-diffuser 26 is mounted at the outlet of the wheel 20 and comprises a first annular portion forming a rectifier 26a and a second annular portion forming a diffuser 26b. The first portion is oriented radially and the second portion is oriented towards the chamber 14 with an axial component. This type of rectifier-diffuser 26 is known.

[0068] The distributor 28 is a bladed distributor, that is to say, it comprises an annular row of blades 28a. It is axially interposed between the outlet of the chamber 14 and the moving wheel 22.

[0069] The moving wheel 22 also includes an annular row of blades 22a which are mounted on the periphery of a disk 22b. The blades 22a include feet which are mounted axially in recesses on the outer periphery of the disk 22b in a known manner.

[0070] The blades 28a of the distributor 28 extend between two annular ferrules 28b, 28c of the distributor 28, which delimit between themselves a second portion of the turbine stream, located upstream of the aforementioned first portion. The ferrules 28b, 28c may be formed by platforms placed circumferentially end to end.

[0071] The distributor 28 further includes a foot 28d which extends radially inward from the inner ferrule 28b.

[0072] The stator further comprises a lamination arrangement 32 which provides the connection between the rectifier-diffuser 26 and the distributor 28, and more particularly between the rectifier-diffuser 26 and a first annular flange 34 integral with the distributor 28. In the example shown, the first flange 34 comprises an outer periphery 34a fixed to the inner periphery of the distributor 28 and in particular to its base 28d, and an inner periphery 34b fixed to the lamination arrangement 32. Preferably, the inner periphery 34b of the flange 34 comprises an annular flange 35 for fixing to the lamination arrangement 32.

[0073] A second annular flange 36 can be fixed to the wheel 22. The flange 36 comprises an outer periphery 36a bearing axially on the outer periphery of the disc, in view of of the retention of the blades (by axial support of their feet on the flange 36) on the disc 22b, and an internal periphery 36b fixed to the shaft 18. In particular, in the example shown, the internal periphery 36b is axially intercalated between a portion of shaft 18a, located upstream and integral with the wheel 20 and another portion of shaft 18b, located downstream and integral with the disc 22b.

[0074] At least one annular sealing gasket 38 is preferably mounted between the second flange 36 and the first flange 34. The gasket 38 is preferably labyrinth-shaped and includes annular flaps 38a carried by or formed on the second flange 36 and adapted to cooperate by friction with at least one abradable ring 38b carried by the first flange 34. Preferably, the gasket 38 is located radially inside the flange 35 and thus surrounded by this flange 35.

[0075] The arrangement of sheets 32 is both axially intercalated between the wheel 20 and the distributor 28, or here the flanges 34, 36, and radially between the shaft 18 and the combustion chamber 14.

[0076] As its name indicates, the arrangement of sheets 32 is formed by sheets or portions of sheets which allow in particular to guide a part of the air exiting the rectifier-diffuser 26, and in particular the part of the air which bypasses the chamber 14 radially from the inside.

[0077] Figures 1 and 2 show the air Fl exiting the centrifugal compressor 12 and supplying the rectifier-diffuser 26, as well as the air F2 exiting the rectifier-diffuser. Part of this air F2 bypasses the chamber 14 internally and is designated as f2. The remainder of this air enters the chamber 14 or bypasses the chamber 14 radially externally.

[0078] The arrangement of sheets 32 includes a first annular sheet 32a or portion of annular sheet which is surrounded by the internal wall 14a of the chamber 14 and which defines with this internal wall 14a a first annular conduit 40 for the passage of air fl, this air fl being intended to flow from upstream to downstream in this first conduit 40.

[0079] The sheet metal 32a extends for example from the inner periphery of the rectifier-diffuser 26 to an annular flange 42 for fixing to the flange 35 of the first flange 34.

[0080] In the example shown, the sheet metal 32a essentially comprises two portions: a first upstream portion 32al, which is cylindrical, and a second downstream portion 32a2, which is frustoconical and converges downstream. The first portion 32a1 has an upstream end connected to the inner periphery of the rectifier-diffuser 26 and a downstream end located inside the inner wall 14a of the chamber 14, and which is connected to the upstream end of the second portion 32a2. This second portion 32a2 is substantially parallel to the wall 14a of the chamber and its inner periphery is connected to the flange 42.

[0081] The flange 42 includes axial ports aligned with ports in the flange 35 for the passage of fastening elements 44, such as screw-nuts. Unlike prior art solutions, these flanges 42, 35 do not have axial air passage ports.

[0082] In the example shown, however, the flange 42 includes lunules 46 or radially oriented lights for the passage of air in a radial direction in particular from the downstream end of the first conduit 40 (arrow f2 in figures 1 and 3).

[0083] The arrangement of sheets 32 includes a second annular sheet 32b or portion of annular sheet that surrounds the shaft 18, and in particular the portion of shaft 18a, and which, together with this shaft 18, defines a second annular air passage 48. This second passage 48 is supplied with air by the first passage 40, in particular through the lunules 46, and the air f3 is intended to flow from downstream to upstream in this second passage 48.

[0084] The sheet metal 32b extends for example upstream from the flange 42 of the sheet metal 32a.

[0085] In the example shown, the sheet metal 32b essentially comprises two portions, namely a first downstream portion 32b1 which is frustoconical and converges upstream, and a second upstream portion 32b2 which is cylindrical. The first portion 32b1 has a downstream end connected to the flange 42 and an upstream end which is connected to the downstream end of the second portion 32b2. This second portion 32b2 is preferably located at a radial distance from the shaft 18 so that the conduit 48 has a diameter.

[0086] The first portion 32b 1 can be located axially opposite the second flange 36, in particular opposite a radial wall 36c of the second flange 36 which extends between the shaft 18 and the first flange 34.

[0087] The first portion 32b 1 can be located radially inside the second portion 32a2 and can therefore be surrounded by this portion 32a2 as in the example shown.

[0088] The second portion 32b2 can be located radially inside the first portion 32a 1.

[0089] The arrangement of sheets 32 includes a third annular sheet 32c or portion of annular sheet which is located, preferably downstream (or opposite) the wheel 20 and which extends radially from the inside to the outside from the second sheet 32b to the exit of the wheel 20.

[0090] This third sheet metal 32c defines with a downstream radial face 20a of the wheel 20 a third annular air passage 50 f4 which is supplied with air by the second conduit 48. The air f4 is intended to flow radially from the inside to the outside in this third conduit 50 and to be recompressed by vortex effect due to its passage near the face 20a of the wheel 20.

[0091] The sheet metal 32c extends for example from the upstream end of the sheet metal 32b to the inner periphery of the rectifier-diffuser 26. The sheets metals 32a and 32c can be connected to the rectifier-diffuser 26 in the same area as in the example shown.

[0092] In the example shown, the sheet metal 32c essentially comprises two portions: a first downstream portion 32c1, which is frustoconical and flared upstream, and a second upstream portion 32c2, which is radial and extends outwards. The first portion 32c1 has a downstream end or inner periphery connected to the upstream end of the sheet metal 32b, and in particular to its portion 32b2, and an upstream end or outer periphery connected to the radially inner end of the second portion 32c2. This second portion 32c2 is connected to the rectifier-diffuser 26, in particular to the upstream end of the sheet metal 32a.

[0093] The sheet 32c can be located radially inside the sheet 32a, and therefore be surrounded by the sheet 32a. In particular, the portions 32c 1, 32c2 can be surrounded by the first portion 32a 1 of the sheet 32a.

[0094] The first portion 32c 1 can be located axially opposite portion 32b 1. The second portion 32c2 can be located axially opposite portion 32a2 and / or flange 42.

[0095] In the example shown, it can be seen that the arrangement of sheets 32 internally delimits an internal annular cavity 54. This cavity 54 is delimited externally by sheet 32a, internally by sheet 32, upstream by sheet 32c, and downstream by portions 32a2 and 32b1 of sheets 32a, 32b.

[0096] The sheet metal arrangement 32 may include annular stiffening ribs 52. In the example shown, this is the case for sheet metal 32 and in particular its second portion 32b2. The ribs 52 are located radially inside the internal cavity 54 of the sheet metal arrangement 32. The special feature of the module 10 is that it also includes at least one air injector 56 which allows the distributor 28 to be ventilated (Figures 1 and 3).

[0097] This injector 56 allows ventilation air to be injected at the distributor 28 and in particular at its internal annular ferrule 28b. The injector 56 thus has at least one air outlet 56b oriented to open towards the distributor 28, for example to open towards its internal ferrule 28b and / or towards its base 28d.

[0098] According to the invention, the arrangement of sheet metal 32 is formed as a single piece with the injector 56, as can be seen in the drawings. Furthermore, the arrangement of sheet metal 32 includes openings 64, 66 for drawing air f5 from the third duct 50 and supplying the injector 56 with this drawn air f5.

[0099] Preferably, the arrangement of sheet metal 32 includes at least a first opening 64 upstream for the intake of air f5 in the third duct 50, and at least a second opening 66 downstream for supplying the injector 56 with this air 15 taken from it.

[0100] As in the example shown, the first opening 64 can be formed by an annular row of orifices which is located at the level of the external periphery of the wheel 20, and the second opening 66 is formed by another annular row of orifices which is preferably formed in the first annular sheet 32a.

[0101] Advantageously, the first opening 64 or its orifices form(s) an air inlet into the internal cavity 54, and the second opening 66 or its orifices form(s) an air outlet from this cavity 54.

[0102] In the example shown, the first opening 64 (or its orifices) is formed in the portion 32c2 of the sheet 32c, closest to the outer periphery of this sheet 32c. The second opening 66 (or its orifices) is formed in the portion 32a2 of the sheet 32a, closest to the flange 42.

[0103] Advantageously and as illustrated in the drawings, the injector 56 comprises an annular row of nozzles 58.

[0104] Each of the nozzles 58 preferably has a generally straight shape to better guide the air drawn in.

[0105] In the example shown, each of the nozzles 58 extends from upstream to downstream radially outwards or parallel to axis A.

[0106] The number of nozzles 58 is for example between 5 and 30.

[0107] As can be seen in Figures 1 and 3 for example, the nozzles 58 can be oriented to open towards the internal annular face of the internal ferrule 28b of the distributor 28.

[0108] The nozzles 58 can be formed by tubes and have internal passages 62 which open at one end inside the cavity 54 to be in fluidic communication with the inside of the cavity 54. The opposite end of each passage 62 forms the air outlet 56b and can open radially to the outside as in the example shown.

[0109] The drawings show that the injector 56 is located radially outside the flange 42 and therefore surrounds this flange 42. It can also be seen that the injector 56 can pass through ports 70 of an internal annular rim 72 of the combustion chamber 14. This internal annular rim 72 is connected by its external periphery to a downstream end of the internal wall 14a of the chamber 14.

[0110] The internal annular rim 72 has its inner periphery bearing radially on a connecting wall 73, preferably annular, fixed or connected to the foot 28d of the distributor 28. The injector 56 can open at this connecting wall 73, and in particular at the outer periphery of this connecting wall 73. The connecting wall 73, and in particular its inner periphery, can be fixed or connected to the flanges 42, 35 and for example formed in one piece with injector 56, as illustrated in the drawings.

[0111] The connecting wall 73, and in particular its external periphery, can be secured to the foot 28d of the distributor 28 by at least one pin 75 oriented axially and passing for example through holes in the connecting wall 73 and the foot 28d, or even also through the external periphery of the first flange 34.

[0112] In the example shown, the injector 56 can be considered as being at least partly radially intercalated between the first flange 34 and the internal annular ferrule 28b of the distributor 28.

[0113] It can be seen in the drawings that the arrangement of sheets 32 can be formed in one piece, including with the flange 42 and the straightener-diffuser 26.

[0114] It is therefore understood that the air circulates in module 10 as follows. Air Fl exits the centrifugal compressor 12 at a given pressure and flows into the rectifier-diffuser 26, which diffuses air F2. Part of this air Fl bypasses the chamber 14 internally and flows into the conduit 40 and passes through the lunules 46. The air f2, f3 then flows into the conduit 48 and into the conduit 50. When the air f4 rises along the downstream face 20a of the impeller 20, it is further compressed by vortex effect and has a pressure higher than that at the outlet of the impeller 20. This air f5 passes through the opening 64, enters the cavity 54, and then exits through the opening 66 to supply the injector with air f6, which supplies the distributor.

[0115] Although the temperature of the air f4 can also increase by viscous friction with the wheel 20, this air will have time to recover a temperature close to or identical to the air F2 or fl due to the passage of the air f5 through the arrangement of sheets 32 which is globally at the temperature of the air F2, fl.

[0116] The air circulation in the embodiment variant of figures 4 to 6 is slightly different.

[0117] In this variant, the air f6 which supplies the injector 56 does not come from the cavity 54.

[0118] The first sheet 32a or portion of sheet has a double annular skin which extends from the opening 64 to the opening 66 and which defines at least one air circulation channel 74 between the openings 64, 66.

[0119] There may be a single annular channel which extends continuously over 360° and which is connected to all the internal passages 62 of the nozzles 58. Alternatively, the number of channels 74 is equal to the number of nozzles 58, and each of the channels 74 is associated with a nozzle 58 and in particular supplies that nozzle.

[0120] Each of the channels 74 can have an elongated shape and extend parallel to the axis A. In particular, each nozzle 58 can extend in the axial extension of the corresponding channel 74.

[0121] Air Fl exits the centrifugal compressor 12 at a given pressure and flows through the rectifier-diffuser 26 which diffuses air F2. Air fl bypasses the chamber 14 from the inside and flows through the conduit 40. This air f2 passes through the lunules 46 to find itself directly inside the cavity 54. The air f3 contained in the cavity 54 exits through at least one opening 76 located on the inner periphery of the lamination arrangement and in particular in its second lamination 32b or portion of lamination. This air f3 is found in the conduit 48 to flow from downstream to upstream into the conduit 50. When the air f4 rises along the downstream face 20a of the wheel 20, it is further compressed by vortex effect and has a pressure greater than that at the outlet of the wheel 20. This air f5 enters the channels 74 through the opening 64 and then circulates in these channels 74 to the injector 56, and in particular to the nozzles 58.Air f6 is routed to outlet 56b and injected at the internal ferrule 28b of distributor 28 for cooling.

[0122] In this embodiment, even if the conduits 40, 48 do not communicate directly with each other through the lunules 46, the conduit 48 remains supplied with air by the conduit 40 insofar as part of the air which flows in the conduit 40 passes through the cavity 54 to supply the conduit 50.

[0123] Although the temperature of the air f4 can also increase by viscous friction with the wheel 20, this air will have time to recover a temperature close to or identical to the air F2 or fl due to the passage of the air f5 through the channel 74 or channels 74 and the injector 56 which are globally at the temperature of the air F2, fl.

[0124] Although not shown, fins could be present on the radial face 20a of the wheel in order to accentuate the air recompression phenomenon f4.

[0125] In general, the invention allows the distributor to be supplied with air at a higher pressure and with an unchanged temperature. This allows it to be cooled with greater pressure and therefore greater flow rate while maintaining the temperature without compression, thus improving the cooling of the distributor.

Claims

1. Demands Module (10) for an aircraft turbomachine, this module (10) comprising: - a rotor comprising a centrifugal compressor impeller (20) (12) and a turbine impeller (22) (16), the impeller (20) and the turbine impeller (22) being connected to each other by a shaft (18) that rotates about an axis (A), - a stator comprising a rectifier-diffuser (26) mounted at the output of the wheel (20) and a turbine distributor (28) mounted upstream of the rotating wheel (22), - an annular combustion chamber (14) also forming part of the stator and axially interposed between the rectifier-diffuser (26) and the distributor (28), the combustion chamber (14) comprising two coaxial annular walls, respectively internal (14a) and external (14b), which are connected upstream by an annular chamber bottom (14c), - at least one ventilation air injector (56) also forming part of the stator, said injector (56) being surrounded by the combustion chamber (14), and - a lamination arrangement (32) connecting the rectifier-diffuser (26) to the distributor (28) and to the injector (56), this lamination arrangement (32) also forming part of the stator and comprising: + a first annular sheet (32a) or portion of annular sheet which is surrounded by said internal wall (14a) of the chamber (14) and which defines with this internal wall (14a) a first annular duct (40) for the passage of air (fl) exiting the rectifier-diffuser (26), the air (fl) being intended to flow from upstream to downstream in this first duct (40), + a second annular plate (32b) or portion of annular plate which surrounds said shaft (18) and which, together with this shaft (18), defines a second annular air passage (48), this second passage (48) being supplied with air by the first passage (40) and the air (f3) being intended to flow from downstream to upstream in this second passage (48), and + a third annular plate (32c) or portion of annular plate which is located downstream of the impeller (20) and which extends radially from the inside to the outside from the second plate (32b) or portion of plate to the outlet of the impeller (20), this third plate (32c) or portion of sheet metal defining with a downstream radial face (20a) of the wheel (20) a third annular air passage duct (50) which is supplied with air by the second duct (48), the air (f4) being intended to flow radially from the inside to the outside in this third duct (50), characterized in that the arrangement of sheet metal (32) is formed in one piece with said at least one injector (56) which has at least one air outlet (56b) which opens towards said distributor (28), and the arrangement of sheet metal (32) includes openings (64) for the sampling of air (f5) in the third duct (50) and the supplying of said injector (56) with this sampling air.

2. Module (10) according to claim 1, wherein the arrangement of sheets (32) includes at least one first opening (64) upstream for the sampling of air (f5) in the third conduit (50), and at least one second opening (66) downstream for supplying said at least one injector (56) with this sampling air.

3. Module (10) according to claim 2, wherein said at least a first opening (64) is formed by an annular row of orifices which is located at the level of the external periphery of the wheel (20), and said at least a second opening (66) is formed by another annular row of orifices which is preferably formed in said first annular sheet (32a) or portion of sheet.

4. Module (10) according to claim 2 or 3, wherein the arrangement of sheets (32) delimits an internal annular cavity (54) which is radially intercalated between the shaft (18) and the combustion chamber (14) and which includes an air inlet formed by said at least a first opening (64), and an air outlet formed by said at least a second opening (66).

5. Module (10) according to claim 2 or 3, wherein the arrangement of sheets (32) forms an internal annular cavity (54) which is radially intercalated between the shaft (18) and the combustion chamber (14), the first sheet (32a) or portion of sheet comprising at least one air circulation channel from said at least one first opening (64) to said at least one second opening (66).

6. Module (10) according to any one of the preceding claims, wherein said at least one injector (56) extends axially downstream from a sheet (32b) or portion of sheet of the arrangement of sheets (32), such as said first sheet (32a) or portion of sheet.

7. Module (30) according to any one of the preceding claims, wherein each injector (56) is formed by a nozzle (58) which extends along a longitudinal extension direction.

8. Module (10) according to claim 7, wherein each of the nozzles (58) has a generally rectilinear shape.

9. Module (10) according to claim 7 or 8, wherein each of the nozzles (58) extends from upstream to downstream and radially outwards or parallel to said axis (A).

10. Module (10) according to any one of the preceding claims, wherein the arrangement of sheets (32) comprises an annular flange (42) for attachment to an annular flange (34), referred to as the first flange, integral with said distributor (28), said at least one injector (56) being located radially outside this flange (42).

11. Module (10) according to claim 10, wherein the flange (42) is radially traversed by lunules (46) or lights for the fluidic communication of said first conduit (40) with said second conduit (48).

12. Module (10) according to any one of the preceding claims, wherein said at least one injector (56) passes through ports (70) of an internal annular rim (72) of the combustion chamber (14), said internal annular rim (72) being connected by its outer periphery to a downstream end of said internal annular wall (14a) of the chamber (14).

13. Module (10) according to any one of the preceding claims, wherein said at least one outlet (56b) of said at least one injector (56) is oriented to open radially outwards.

14. Module (10) according to any one of the preceding claims, wherein said distributor (28) comprises two annular ferrules, respectively internal (28b) and external (28c), between which vanes (28a) extend, the distributor further comprising a foot (28d) which projects radially inward from the internal ferrule (28b), said at least one outlet (56b) of said at least one injector (56) being oriented to open into the internal ferrule (28b) and / or to open into the foot (28d) of the distributor (28).

15. Module (10) according to claim 14, depending on claim 12, wherein said internal annular rim (72) has its inner periphery which is radially supported on a connecting wall (73) fixed or connected to the foot (28d) of the distributor (28).

16. Module (10) according to claim 15, wherein said at least one injector (56) opens at the level of said connecting wall (73), and in particular at the external periphery of this connecting wall (73).

17. Module (10) according to any one of claims 14 to 16, depending on claim 10, wherein said at least one injector (56) is radially intercalated between said first flange (36) and said internal annular ferrule (28b) of the distributor (28).

18. Turbomachine for an aircraft, comprising at least one module (10) according to any one of the preceding claims.

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