Bladed wheel for an aircraft turbomachine, and aircraft turbomachine

Abstract

The invention relates to a bladed wheel (20) for an aircraft turbomachine, comprising a plurality of blades (26) with a shroud (32) extending circumferentially on either side of the blade tip (46) respectively in a first shroud portion (32a) and a second shroud portion (32b). Between a first blade and an adjacent second blade of the wheel, the latter comprises a member (50) for reconstituting a gas flow path, which member is arranged in a first material recess (54a) provided on the radially inner surface (36a) of the first shroud portion (32a) of the first blade, and in a second material recess (54b) provided on the radially inner surface (36a) of the second shroud portion (32b) of the second blade, the first and second recesses each having a bottom surface (56) intended to cooperate by friction with a radially outer friction surface (58a) of the member (50).

Description

[0001] DESCRIPTION

[0002] TITLE :

[0003] BLADED WHEEL FOR AIRCRAFT TURBOMACHINE AND AIRCRAFT TURBOMACHINE

[0004] TECHNICAL FIELD

[0005] The present invention relates to the field of aircraft turbomachines, and more precisely to the design of the bladed wheels forming the turbines and compressors of these turbomachines.

[0006] It concerns more specifically the dynamic damping by friction of the blades, which follow one another in the circumferential direction to form an annular row of blades.

[0007] The invention applies to all turbomachine designs, for example turbojets with a fan driven directly by a low-pressure body, or driven indirectly by a reducer.

[0008] STATE OF PRIOR ART

[0009] The compressors and turbines of aircraft turbomachines are made by an axial succession of fixed and moving bladed wheels, also called stator bladed wheels, and rotor bladed wheels. In the case where such a bladed wheel is angularly sectored, namely in the circumferential direction of the wheel, it is usually appropriate to limit the vibrational stresses on the blades arranged adjacently in the circumferential direction of the wheel.

[0010] To do this, means are implemented to ensure dynamic damping of these sectors, by dissipating the resonance energy by friction between the blade heels. Such a damping solution is for example known from document FR 3 085 712 Al.

[0011] Another more traditional solution consists of implementing contact friction technology between the heels of adjacent blades with particular shapes. This technology, also known as "pretorsion", is characterized by a specific cut of the two opposite circumferential faces of the heel, with a protrusion on the extrados side, and a complementary shaped imprint on the intrados side. The two-by-two cooperation of these circumferential faces allows the two adjacent heels to be held in relation to each other, in the axial direction. This pretorsion technology is also called "interlock".

[0012] When assembling the blades, a support of the circumferential contact faces is generated by means of an angular deformation of the blade, constituting the desired pretorsion.

[0013] In operation, blade vibrations induce relative slippage at the circumferential faces of the heels, which, coupled with contact pressures, create friction damping.

[0014] With this technology, the contact force between the stubs can vary during the operation of the turbomachine. This variation can come from the natural rotation of the blade around its twist axis (clockwise or counterclockwise), or from the relative movement of adjacent stubs in the circumferential direction (approaching or separating). When assembling the blades, it is necessary to take into account these possible variations in operation, and to ensure that at high speed, i.e. at the speed where dynamic damping is mainly sought, the target contact force is achieved. This can lead to applying a very high contact force during blade assembly, which results in significant static overstresses, likely to weaken the blades and / or reduce their service life. This disadvantage is more or less restrictive, depending on the material used and its capacity to withstand such stresses.For example, for blades made of ceramic matrix composite material, also known as CMC material, the permissible mechanical stresses often remain low, which makes the blades not very tolerant to this pre-torsion principle. Thus, when a blade is made of CMC material, it may prove incompatible with the need to apply strong pre-torsion during assembly, required for satisfactory damping at the desired speed.

[0015] Other dynamic damping solutions are known, such as adding friction elements to the interface between the beads, at the level of their circumferential faces which cooperate two by two. These solutions generally have the disadvantage of generating aerodynamic disturbances at the level of the vein.

[0016] STATEMENT OF THE INVENTION

[0017] To address the drawbacks mentioned above, the invention firstly relates to a bladed wheel for an aircraft turbomachine, according to the characteristics of each of claims 1 and 6.

[0018] The invention is thus generally based on splitting the existing heels into several pieces, in particular so as to provide the dynamic damping function, by friction between these pieces.

[0019] The invention thus provides a simple, reliable, high-performance, and low-mass solution to the problems set out above, and the principle of which makes it possible to overcome the constraints associated with the principle of pre-torsion of the blades encountered in the prior art. In particular, it is no longer necessary to introduce high static pre-torsion constraints in the angular sectors during their assembly, and the machining of complementary complex shapes on the opposite circumferential faces of the heels is no longer required. Advantageously, the invention allows the use of various materials for producing the blades, including CMC materials.

[0020] In the invention, the vein reconstitution member can therefore come into contact with the heel portions in which the material recesses are arranged, forming a sort of imprint. This makes it possible to generate, under the effect of the centrifugal force observed in operation and in combination with the bottom surface of these recesses, a vibration damping friction. Due to the possibility of providing friction surfaces of large dimensions, the contact pressures are advantageously reduced, and the wear of the parts slowed down. Support points could nevertheless be provided on these friction surfaces, for example three support points to have an isostatic system. In such a case, the recesses are judiciously positioned to locate the support points according to the desired arrangement.In addition, the vein reconstruction member may also have a simple design making it easy to manufacture, for example by forming a plate, such as a machined and / or deformed and / or cut plate.

[0021] The material recesses in the heel portions not only allow the thickness of these heel portions to be reduced, but also provide better aerodynamic performance to the reconstituted vein, by housing / embedding all or part of the thickness of the reconstitution member in these two recesses.

[0022] By duplicating the principle of the invention on several sets of two adjacent blades of the wheel, or even on the entire bladed wheel, the adjacent vein reconstitution members provide satisfactory aerodynamic continuity of the vein. This advantageously generates less disturbance than with previous solutions consisting of adding friction elements to the interface between the heels, at the level of their circumferential faces which cooperate two by two. In addition, the axial and radial sealing is advantageously improved.

[0023] Furthermore, the general inventive concept which emerges from the two formulations of the invention, respectively via claims 1 and 6, also relies on the structuring of the heel portions in the circumferential direction to cooperate and retain the vein reconstitution member, forming a dynamic friction damper. This structuring is carried out in the first case by removing material with the presence of the circumferential notches, while in the second case, the structuring is carried out by adding material with the radial retaining tabs.

[0024] This structuring of the heel portions in the circumferential direction, specific to the present invention, allows the retention means of the reconstitution member to extend in length in this same circumferential direction, and not in the axial direction. The space available in the circumferential direction being greater than that in the axial direction of the blades, the installation of the radial retention means is thereby facilitated, and their performance improved.

[0025] Finally, this same inventive concept of circumferential structuring of the heel portions makes it possible to overcome the design constraint encountered in certain solutions of the prior art, requiring a radial shock absorber support which necessarily extends radially between two facing heel portions.

[0026] The invention furthermore preferably provides at least any one of the following optional features, taken individually or in combination.

[0027] Preferably, to have increased aerodynamic performance at the level of the gas circulation vein, the radially internal surface of the reconstitution member, and the radially internal surface of the first and second heel portions receiving this reconstitution member, are flush.

[0028] The preferred characteristics cited below apply to the first definition of the invention, by claim 1.

[0029] Preferably, each pair of fixing notches cooperates with a radial retaining element belonging to said radial retaining means, the radial retaining element being a tongue or a rail, and, in the case of the tongue, the latter preferably has a circumferential length greater than or equal to the cumulative circumferential length of the two notches of the pair of fixing notches concerned. Furthermore, the circumferential length of the tongue may be greater than or equal to that of the plate.

[0030] Preferably, the plate of the reconstitution member is equipped with a single radial retaining element, for example axially centered on this plate, or the plate of the reconstitution member is equipped with several radial retaining elements axially spaced from each other, for example two radial retaining elements arranged respectively at the two opposite axial ends of the plate and arranged to project relative to the latter, radially outwards.

[0031] Preferably, the heel of each of the first and second adjacent blades comprises two sealing members projecting radially outwardly from the base and are axially spaced from each other, and there is provided, within each of the first and second heel portions:

[0032] - a fixing notch arranged axially between the two sealing members; or

[0033] - two fixing notches arranged axially on either side of the assembly formed by the two sealing members; or - a fixing notch arranged axially between the two sealing members and a fixing notch offset axially from the assembly formed by the two sealing members.

[0034] These designs can be combined and others are possible, such as providing two fixing notches arranged axially between the two sealing members.

[0035] Whatever the preferred embodiment envisaged, the heel of each of the two adjacent blades forms, in both directions of the axial direction of the wheel, upstream and downstream spoilers.

[0036] Preferably, a vein reconstitution member is arranged between each set of two adjacent blades of the wheel, implying that these members are circumferentially separated from each other by the blade heads.

[0037] Preferably, the blades are made of ceramic matrix composite material, although other materials may be considered without departing from the scope of the invention. The vein reconstitution member may also be made of ceramic matrix composite material. It could also be made of metallic material.

[0038] Preferably, it is a fixed or mobile bladed wheel, compressor or turbine, and preferably a low pressure turbine mobile wheel.

[0039] Finally, the invention also relates to an aircraft turbomachine, such as a double-flow, double-spool turbojet, comprising at least one such bladed wheel.

[0040] Other advantages and characteristics of the invention will appear in the detailed non-limiting description below.

[0041] BRIEF DESCRIPTION OF THE DRAWINGS

[0042] This description will be made with regard to the attached drawings, among which;

[0043] [Fig. 1] represents a schematic view in longitudinal section of an aircraft turbomachine according to the invention;

[0044] [Fig. 2] represents a more detailed perspective view of a bladed wheel of a low pressure turbine of the turbomachine shown in the preceding figure, the bladed wheel being in the form of a first preferred embodiment of the invention;

[0045] [Fig. 3] represents a partial and enlarged perspective view of a part of the bladed wheel shown in the preceding figure, seen radially from the inside;

[0046] [Fig. 4] represents a view similar to the preceding one, with the vein reconstitution organ having been removed for reasons of clarity;

[0047] [Fig. 5] represents a perspective view of one of the two blades shown in Figures 3 and 4;

[0048] [Fig. 6] represents a perspective view of the other of the two blades shown in Figures 3 and 4;

[0049] [Fig. 7] is a perspective view of the vein reconstruction member shown in Fig. 3;

[0050] [Fig. 8] represents a perspective view similar to that of Fig. 3, seen radially from the outside;

[0051] [Fig. 9] represents a partial and enlarged perspective view of a part of the bladed wheel according to a second preferred embodiment of the invention, seen radially from the inside;

[0052] [Fig. 10] represents a view similar to the preceding one, with the vein reconstitution organ having been removed for reasons of clarity;

[0053] [Fig. 11] represents a perspective view of one of the two blades shown in Figures 9 and 10;

[0054] [Fig. 12] represents a perspective view of the other of the two blades shown in Figures 9 and 10;

[0055] [Fig. 13] is a perspective view of the vein reconstruction member shown in Fig. 9;

[0056] [Fig. 14] represents a perspective view similar to that of figure 9, from another angle of view;

[0057] [Fig. 15] shows a view similar to that of Fig. 13, with the vein reconstitution member being in the form of an alternative; [Fig. 16] shows a view similar to that of Fig. 13, with the vein reconstitution member being in the form of another alternative;

[0058] [Fig. 17] is a perspective view similar to that of Fig. 14, incorporating the vein reconstitution member shown in Fig. 16;

[0059] [Fig. 18] represents a partial and enlarged perspective view of a part of the bladed wheel according to a third preferred embodiment of the invention, seen radially from the inside;

[0060] [Fig. 19] represents a view similar to the preceding one, with the vein reconstitution organ having been removed for reasons of clarity;

[0061] [Fig. 20] is a perspective view of the vein reconstruction member shown in Fig. 18;

[0062] [Fig. 21] represents a perspective view similar to that of figure 18, from another angle of view;

[0063] [Fig. 22] represents a sectional view of a part of the bladed wheel according to a fourth preferred embodiment of the invention, this section being taken along the line XXII-XXII of figure 25;

[0064] [Fig. 23] represents a view similar to the preceding one, with the vein reconstitution organ having been removed for the sake of clarity;

[0065] [Fig. 24] is a perspective view of the vein reconstitution member shown in Fig. 22;

[0066] [Fig. 25] shows a portion of the wheel according to the fourth preferred embodiment, viewed radially from the inside; and

[0067] [Fig. 26] shows a view similar to that of Fig. 22, with the vein reconstitution member being in the form of an alternative.

[0068] DETAILED DISCLOSURE OF PREFERRED EMBODIMENTS

[0069] Referring firstly to Figure 1, there is shown an aircraft turbomachine 1, according to a preferred embodiment of the invention. This is a double-flow, twin-spool turbojet. However, it could be a turbomachine of another type, for example a turboprop, without departing from the scope of the invention. The turbomachine 1 has a longitudinal central axis 2 around which its various components extend. It comprises, from upstream to downstream along a main direction 5 of gas flow through this turbomachine, a fan 3, a low-pressure compressor 4, a high-pressure compressor 6, a combustion chamber 11, a high-pressure turbine 7 and a low-pressure turbine 8. The fan 3 can be driven directly by a low-pressure spool comprising the compressor 4 and the turbine 8, or be driven indirectly by a reducer (not shown).

[0070] Conventionally, after passing through the fan 3, the air divides into a central primary flow 12a and a secondary flow 12b which surrounds the primary flow. The primary flow 12a flows in a main gas circulation vein 14a passing through the compressors 4, 6, the combustion chamber 11 and the turbines 7, 8. The secondary flow 12b flows in a secondary vein 14b delimited radially outwards by a motor casing, surrounded by a nacelle 9.

[0071] Each turbine 7, 8 and each compressor 4, 6 comprises, in a conventional manner known to those skilled in the art, an alternation of mobile bladed wheels and fixed bladed wheels, centered on the axis 2. The invention lies in the design of these bladed wheels, and more particularly in the principle of dynamic damping which is implemented therein.

[0072] Figure 2 shows a mobile bladed wheel 20 according to a first preferred embodiment of the invention, this wheel being preferably intended to form a part of the low pressure turbine 8. Nevertheless, the invention can be applied to the high pressure turbine 7, or even to one of the two compressors 4, 6. In addition, it can be a fixed bladed wheel, without departing from the scope of the invention.

[0073] The bladed wheel 20 comprises a disc 22, centered on the axis 2 and on which are mounted, radially outwardly, a plurality of distinct blades 26 forming an annular row of blades. Each blade 26 comprises a blade 28 forming the aerodynamic part of the blade, as well as a root 30 and a heel 32. In known manner, the root 30 is formed by a part of greater thickness, for example with a bulb-shaped section, which is engaged in a corresponding housing 34 formed at the periphery of the disc 22. Opposite the root 30, radially outwardly, the blade 28 of the blade carries the heel 32, the latter therefore being integral with the blade head, and preferably made in one piece with the other parts thereof.

[0074] Figures 3 and 4 show more detailed views of several adjacent blades 26 of the wheel 20, here two blades 26 which follow one another adjacently in the circumferential direction 24. It is noted that all the blades of the wheel 20 preferably have an identical or similar design. In these figures, the left blade 26 is called the first blade, while the right blade 26 is called the second blade.

[0075] With reference jointly to figures 3 to 8 relating to the first preferred embodiment of the invention, the heel 32 of one of the blades 26, secured to the head 46 of the blade 28 of this same blade, will first be described.

[0076] The heel 32 comprises a base 36, as well as one or more sealing members 38 extending radially outwardly from this base. Here, these are two sealing members 38 which project radially outwardly from the base 36, and which are axially spaced from one another. The members 38 take the form of wipers extending outwardly in a radial direction 35 of the blade in which the root 30 and the heel 32 are spaced from one another, and they also extend circumferentially over the entire circumferential length of the heel 36.

[0077] In the description, the terms internal / external and internal / external, associated with the radial direction 35, are defined in relation to each blade in its environment, and therefore in relation to the root of the blade which radially forms the innermost part of this blade.

[0078] As regards the aforementioned wipers 38, a slight axial inclination of these is possible, such as an inclination towards the upstream, without departing from the scope of the invention. Nevertheless, they are preferably oriented in the circumferential direction 24. The wipers 38 have a distal end facing radially an inner surface of a turbine casing (not shown). They make it possible to control the sealing with this turbine casing, in the operating configuration of the turbojet. Indeed, these wipers 38 are intended to come as close as possible to the surface of the casing in order to provide a sealing function with respect to the primary flow 12a, which passes through the rotating bladed wheel 20.

[0079] The two lips 38 and the base 36 together form a U-shaped structure delimiting a cavity 45 open radially outwards, and usually called a “bathtub”. The base 36 of the heel extends, in the axial direction 37 parallel to the axis 2, beyond the two lips 38 in both directions. In other words, it extends axially beyond the two lips 38 on either side of the base of the heel 32, so as to form respectively an upstream spoiler 42 and a downstream spoiler 44. Also, these two spoilers and the central part of the base of the heel together form a platform delimiting the primary vein, radially outwards.

[0080] To reinforce the mechanical strength of the heel 32, one or more ribs (not shown) may connect the two lips 38, being arranged on the radially external surface 36b of the base of the heel.

[0081] Unlike the embodiments of the prior art, the blade heels 32 do not delimit the entirety of the main vein 14a, the latter also being delimited by vein reconstitution members 50 specific to the present invention, distinct from the heels 32 and arranged between the adjacent blades 26 which hold these same members 50 in place. In order to be able to cooperate with two vein reconstitution members 50 on either side of the blade, each heel 32 extends circumferentially on either side of the blade head 46, respectively forming a first heel portion 32a and a second heel portion 32b. In the figures, the first heel portion 32a corresponds to the one on the right, i.e. on the extrados side of the blade, while the second heel portion 32b corresponds to the one on the left, i.e. on the intrados side of the blade.At the base 36, each of the first and second heel portions 32a, 32b has a radially internal surface 36a partially delimiting the vein 14a, radially outwards.

[0082] Between each set of two adjacent blades 26 of the wheel, namely two blades directly consecutive in the circumferential direction 24, this vein reconstitution member 50 is provided, forming a plate 51, for example a cut and / or deformed and / or machined plate, or a molded plate. Other manufacturing methods remain conceivable, without departing from the scope of the invention. The reconstitution member 50 is preferably made of a metallic material or preferably of CMC material, while the aforementioned blades 26 are also preferably made of CMC material.

[0083] The plate 51, which corresponds to the main part of the vein reconstitution member 50, extends at least partly in the thickness of the first heel portion 32a of the first blade 26, and of the second heel portion 32b of the second blade directly consecutive.

[0084] To do this, the reconstitution member 50 has a part arranged in a first material recess 54a provided on the radially internal surface 36a of the first heel portion 32a of the first blade, and another circumferentially adjacent part, which is itself arranged in a second material recess 54b provided on the radially internal surface 36a of the second heel portion 32b of the second blade. The first and second recesses 54a, 54b are in the form of impressions in the thickness of the base 36 of the heel, with a non-closed impression contour. Indeed, the two adjacent recesses 54a, 54b open circumferentially towards each other, and they therefore also open radially inwards to receive the reconstitution member 50, preferably filling the entirety of these recesses.

[0085] Opposite their ends which face each other in the circumferential direction 24, each recess 54a, 54b has a circumferential end which is preferably close to the blade head of its vane. In the axial direction 37, each recess 54a, 54b preferably extends in the thickness of the base 36 at the level of the space defined between the two wipers 38, with its two axial ends approaching even more preferably radially in line with these wipers, respectively.

[0086] Each recess 54a, 54b has a radially internal bottom surface 56, intended to cooperate by friction with a radially external friction surface 58a of the reconstitution member 50, a radially internal surface 58b of which partly delimits the vein 14a radially outwards. To obtain better aerodynamic performance on the primary flow passing through the vein 14a, it is preferentially provided that the radially internal surface 58b of the reconstitution member 50, and the radially internal surface 36a of the first and second heel portions 32a, 32b receiving this member, are flush. In other words, the member 50 fills the entirety of the two recesses 54a, 54b while preferably maintaining very small assembly clearances, and above all, the member 50 does not extend outside of these recesses in the radial direction 35.

[0087] When all the vein reconstitution members 50 are mounted within the wheel 20, they are spaced from each other in the circumferential direction 24 by the blade heads 46. Thus, together they form a partial ring for reconstitution of the main vein 14a, centered on the axis 2, interrupted circumferentially by these blade heads 46, and internally partly delimiting this same vein 14a having satisfactory aerodynamic continuity. By being at the junction between two adjacent blades, the members 50 also participate in limiting radial gas leaks.

[0088] The organs 50 thus retain a simple shape to manufacture, while fulfilling several functions such as that of reconstituting the main vein, or that of sealing the vein in the radial direction 35.

[0089] Another particularity of the invention lies in the use of the dissociation of the parts described above, to form a dynamic damping device 40. The cooperation of the friction surfaces 58a, 56 in fact makes it possible, in the event of vibratory excitations, to form a dynamic damping device 40 of the blades.

[0090] More precisely, each reconstitution member 50 is therefore the seat of a dynamic damping device 40, with its surface 58a which cooperates by friction on the one hand with the recess bottom surface 56 of the first heel portion 32a of the first blade, and on the other hand with the recess bottom surface 56 of the second heel portion 32b of the second blade.

[0091] Thus, each reconstitution member 50 is associated with the two blades 26 which are arranged on either side thereof, to form with them a dynamic damping device 40, and to ensure its maintenance in position. Indeed, in this first preferred embodiment, the vein reconstitution member 50 is equipped with means for radially retaining the plate in the first and second material recesses 54a, 54b. This is a radial retaining element in the form of a rail 60 which extends circumferentially along the entire length of the plate 51, projecting radially outwards from the external friction surface 58a of this same plate.

[0092] The radial retaining rail 60, for example of T-shaped section, cooperates with two fixing notches 62 made respectively in the first heel portion 32a of the first blade, and in the second heel portion 32b of the second blade. Each fixing notch 62 here extends circumferentially by radially crossing its associated heel portion 32a, 32b. In addition, it opens circumferentially in the direction of the other of the two notches 62, in order to form a pair of fixing notches 62 aligned circumferentially, and located substantially in continuity with one another.

[0093] The base of the T-shaped rail 60 thus passes through the pair of notches 62 with a small clearance, while the head of the T cooperates with the radially external surface 36b of the heel to ensure the radial retention of the reconstitution member 50. In the event of radial clearance in this assembly, this is consumed in operation due to the centrifugal effect to which the member 50 is subjected, allowing it to cooperate by friction with the two radially internal bottom surfaces 56 of the recesses 54a, 54b.

[0094] In this first preferred embodiment, the axial retaining element 60 forming the axial retaining means is unique, for example axially centered on the plate 51. According to a second preferred embodiment shown in FIGS. 9 to 14, two radial retaining elements 64 are provided, arranged respectively at the two opposite axial ends of the plate 51, and arranged to project relative to the latter, radially outwards. These two elements each take the form of a tongue 64. Here, the circumferential length of each tongue 64 is equal or substantially equal to that of the plate 51, and to that of the cumulative circumferential length of the two notches 62 of the pair of notches traversed radially by the tongue concerned.

[0095] Two pairs of fixing notches 62 are therefore provided here to cooperate respectively with the two tabs 64, located at the two axial ends of the plate 51. The two notches 62 on the first heel portion 32a of the first blade are arranged axially on either side of the assembly formed by the two sealing members 38, preferably opening through the heel at the foot of these members 38, externally to the aforementioned assembly. The same applies to the two notches 62 provided on the second heel portion 32b of the second blade.

[0096] The inclination of the tabs 64 relative to the radial direction 35 allows the radial retention of the member 50 in its two dedicated recesses 54a, 54b. Indeed, the tabs 64 cooperate with the radial surface 36b of the heel located opposite the upstream 42 and downstream 44 spoilers.

[0097] Figure 15 represents an alternative for the production of the reconstitution member 50, in which the plate 51 is not flat, but it has a curvature in the axial direction 37. Figures 16 and 17 represent another alternative, in which the two tongues 64 are no longer of rectangular overall shape. They have a trapezoidal shape widening radially outwards, from the junction 66 with the plate 51, junction which corresponds to the part radially crossing the pair of notches 62, and having a circumferential length equal or substantially equal to the cumulative circumferential length of the two notches 62 of the pair crossed.

[0098] Figures 18 to 21 show a third preferred embodiment of the invention, in which the reconstitution member 50 has two tabs 64 with junctions 66 of circumferential length less than that of the tab body, of generally rectangular shape. This makes it possible to provide notches 62 of shorter circumferential length.

[0099] Furthermore, in this third embodiment, if one of the two fixing tabs 64 cooperates with a pair of fixing notches 62 axially offset from the assemblies formed by the sealing members 38, for example by opening at the foot of two of these members 38 arranged in circumferential continuity with one another, the other tab 64 cooperates with a pair of notches 62 axially arranged between the sealing members 38, for example axially centered on the first and second heel portions 32a, 32b. Referring now to Figures 22 to 25, a fourth preferred embodiment of the invention is shown, contrasting with the previous embodiments essentially in that the plate 51 of the reconstitution member 50 corresponds to a part of a flattened tube 68.

[0100] In this fourth embodiment, the first heel portion 32a of the first blade comprises a first radial retaining tab 70a extending circumferentially in the direction of the second blade, and similarly, the second heel portion 32b of the second blade comprises a second radial retaining tab 70b extending circumferentially in the direction of the first tab 70a. These tabs 70a, 70b have a reduced radial thickness, and they define the two material recesses 54a, 54b on the radially internal surface 36a of the heel 36. Furthermore, these tabs are axially offset towards the leading edge of the blades, and each initiated near the blade head 46, to then extend projecting in the circumferential direction 24.

[0101] The plate 51 of the reconstitution member 50 therefore corresponds to a radially internal part of flattened tube 68. Here also, the radially external surface 58a of the plate 51 cooperates by friction with the bottom surfaces 56 of the recesses 54a, 54b, these surfaces 56 corresponding to the radially internal surfaces of the radial retaining tabs 70a, 70b.

[0102] The other part of the flattened tube 68, namely the radially external part also in the form of a plate 53 with curved edges for joining with the plate 51, constitutes the radial retaining means of this plate 51 by covering radially outwards the first and second tabs 70a, 70b. Indeed, at its two opposite circumferential ends, the flattened tube 68 is penetrated by the first and second tabs 70a, 70b, which makes it possible not only to form the damping device by friction between the surfaces 56, 58a, but also to retain the plate 51 in all directions 24, 35, 37. The two ends of the flattened tube 68 thus form hollow radial retaining means, penetrated respectively by the first and second radial retaining tabs 70a, 70b. Alternatively, the flattened tube 68 may be split along the circumferential direction 24.According to yet another alternative shown in Figure 26, the flattened tube is replaced by a structure 74 of C-shaped section opening radially outwards. The reconstitution member 50 then integrates hooks 72 at the level of the opposite axial edges of the plate 51, to form the radial retention means of this plate by cooperating with the axial edges of the tongues 70a, 70b, which penetrate into the hooks.

[0103] Of course, various modifications may be made by those skilled in the art to the invention which has just been described, solely by way of non-limiting examples and within the limits of the scope of the appended claims. In particular, the technical characteristics of the different preferred embodiments and their alternatives are interchangeable and / or cumulative.

Claims

CLAIMS 1. Bladed wheel (20) for an aircraft turbomachine, the wheel comprising several blades (26) succeeding one another in a circumferential direction (24) of the wheel so as to form an annular row of blades, each of the blades comprising a blade (28) as well as a heel (32) integral with the blade head and arranged to project therefrom radially outwards, the heel comprising a base (36) as well as at least one sealing member (38) projecting radially outwards from the base (36), the heel extending circumferentially on either side of the blade head (46) respectively in a first heel portion (32a), and a second heel portion (32b), each of the first and second heel portions having a radially internal surface (36a) partially delimiting a gas circulation vein (14a), characterized in that between a first blade and a second adjacent blade of the wheel,the latter also comprises a member (50) for reconstituting the gas circulation vein (14a), the reconstitution member being arranged in a first material recess (54a) provided on the radially internal surface (36a) of the first heel portion (32a) of the first blade, and in a second material recess (54b) provided on the radially internal surface (36a) of the second heel portion (32b) of the second blade, the first and second material recesses opening circumferentially towards each other, and each having a radially internal bottom surface (56) intended to cooperate by friction with a radially external friction surface (58a) of the reconstitution member (50), a radially internal surface (58b) of which partially delimits the vein in that the vein reconstitution member (50) forms a plate (51),and in that the vein reconstitution member (50) comprises means for radially retaining the plate (51) in the first and second material recesses (54a, 54b), the radial retaining means cooperating with fixing notches (62) made in the first heel portion (32a) of the first blade and in the second heel portion (32b) of the second blade, each fixing notch (62) extending circumferentially and passing through its associated heel portion by opening, circumferentially towards another fixing notch, in order to form one or more pairs of fixing notches (62) aligned circumferentially two by two.

2. Bladed wheel according to claim 1, characterized in that the radially internal surface (58b) of the reconstitution member (50), and the radially internal surface (36a) of the first and second heel portions (32a, 32b) receiving this reconstitution member, are flush.

3. Bladed wheel according to claim 1 or 2, characterized in that each pair of fixing notches (62) cooperates with a radial retaining element (60, 64) belonging to said radial retaining means, the radial retaining element being a tongue (64) or a rail (60), and, in the case of the tongue, the latter preferably has a circumferential length greater than or equal to the cumulative circumferential length of the two notches (62) of the pair of fixing notches concerned.

4. Bladed wheel according to claim 3, characterized in that the plate (51) of the reconstitution member (50) is equipped with a single radial retaining element (60), for example axially centered on this plate, or in that the plate (51) of the reconstitution member (50) is equipped with several radial retaining elements (64) axially spaced from each other, for example two radial retaining elements (64) arranged respectively at the two opposite axial ends of the plate (51) and arranged projecting relative to the latter, radially outwards.

5. A bladed wheel according to any one of the preceding claims, characterized in that the heel (32) of each of the first and second adjacent blades (26) comprises two sealing members (38) projecting radially outwardly from the base (36) and are axially spaced from each other, and in that there is provided, within each of the first and second heel portions (32a, 32b): - a fixing notch (62) arranged axially between the two sealing members (38); or - two fixing notches (62) arranged axially on either side of the assembly formed by the two sealing members (38); or - a fixing notch (62) arranged axially between the two sealing members (38) and a fixing notch (62) axially offset from the assembly formed by the two sealing members (38).

6. Bladed wheel (20) for an aircraft turbomachine, the wheel comprising several blades (26) succeeding one another in a circumferential direction (24) of the wheel so as to form an annular row of blades, each of the blades comprising a blade (28) as well as a heel (32) integral with the blade head and arranged to project therefrom radially outwards, the heel comprising a base (36) as well as at least one sealing member (38) projecting radially outwards from the base (36), the heel extending circumferentially on either side of the blade head (46) respectively in a first heel portion (32a), and a second heel portion (32b), each of the first and second heel portions having a radially internal surface (36a) partially delimiting a gas circulation vein (14a), characterized in that between a first blade and a second adjacent blade of the wheel,the latter also comprises a member (50) for reconstituting the gas circulation vein (14a), the reconstitution member being arranged in a first material recess (54a) provided on the radially internal surface (36a) of the first heel portion (32a) of the first blade, and in a second material recess (54b) provided on the radially internal surface (36a) of the second heel portion (32b) of the second blade, the first and second material recesses opening circumferentially towards each other, and each having a radially internal bottom surface (56) intended to cooperate by friction with a radially external friction surface (58a) of the reconstitution member (50), a radially internal surface (58b) of which partially delimits the vein in that the vein reconstitution member (50) forms a plate (51),and in that the first heel portion (32a) of the first blade comprises a first radial retaining tab (70a) extending circumferentially in the direction of the second blade, the second heel portion (32b) of the second blade comprising a second radial retaining tab (70b) extending circumferentially in the direction of the first radial retaining tab (70a), and in that the reconstitution member, of vein (50) comprises, at its two opposite circumferential ends, hollow radial retaining means (53, 72) penetrated respectively by the first and second radial retaining tabs (70a, 70b), and, preferably, the vein reconstitution member (50) integrating hooks (72) at the level of the opposite axial edges of the plate (51) to form said radial retaining means, or the plate (51) corresponds to a part of a flattened tube (68), another part (53) of which forms said radial retaining means by covering radially outwards the first and second radial retaining tabs (70a, 70b).

7. Bladed wheel according to claim 6, characterized in that the radially internal surface (58b) of the reconstitution member (50), and the radially internal surface (36a) of the first and second heel portions (32a, 32b) receiving this reconstitution member, are flush.

8. Bladed wheel according to any one of the preceding claims, characterized in that the blades (26) and / or the reconstitution members (50) are made of ceramic matrix composite material.

9. Aircraft turbomachine (1) comprising at least one bladed wheel (20) according to any one of the preceding claims.

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