Stator member for a turbine engine, equipped with at least one fin, and method for mounting at least one fin in the stator member

Abstract

The invention relates to a stator member (21) of a turbine engine (1), in particular of an aircraft, which extends around a longitudinal axis and comprises two circumferentially adjacent stator vanes (20, 20'), the two stator vanes each comprising a vane body (22) extending radially from an annular wall (23) centred on the longitudinal axis, the stator member comprising a fin (25) arranged circumferentially between the two stator vanes (20, 20'). According to the invention, the annular wall comprises a recess (28) of predetermined shape formed in the body thereof, open onto a radially outer surface (23a) of the annular wall and at a distance from the upstream and downstream edges (24a, 25b) of the annular wall, the fin comprising a root (26), with a shape matching the recess, intended to be removably arranged in the recess, and a fin body (27) which extends radially from the root and which is elongate in a direction of elongation substantially parallel to the longitudinal axis.

Description

Description TITLE: STATOR COMPONENT FOR A TURBOMACHINE EQUIPPED WITH AT LEAST ONE FIN AND METHOD FOR MOUNTING AT LEAST ONE FIN IN THE STATOR COMPONENT. Technical field of the invention

[0001] The present invention relates to the field of turbomachines, and in particular aircraft, in which air flows circulate from upstream to downstream. It relates more specifically, but not exclusively, to a turbomachine stator member comprising stator blades and at least one fin. It also relates to a method of mounting at least one fin in the stator member. Technological background

[0002] An aircraft turbomachine may be equipped with one or more stator components such as a stator blade stage of a compressor or a turbine. Turbines and compressors generally comprise several stages of stator blades and moving blades that are alternated along the longitudinal axis of the turbomachine. The stator blades extend radially between two radially inner and outer walls. An airflow passes through the compressors and turbines, and circulates between the different stages of stator blades and moving blades thereof. The stator blades allow the airflow to be straightened downstream of the moving blades. However, vortices are generated at the radially inner wall during the interaction of the airflow and the stator blades. The vortices create a friction loss and can also cause aerodynamic separations if they strike the extrados surface of the stator blades.

[0003] Fins have been arranged between adjacent stator blades in order to reduce or even eliminate these vortices. These fins are generally smaller than the stator blades. There are several examples of fins such as those described in patent documents US-A1-2018 / 017079, FR-B1-3106614, FR1854134, and FR3081185. However, the arrangement of these fins in the stator members seems complex for the most part compared to the radially internal wall for example and the fins do not seem to be easy to mount and / or dismount in the event of maintenance without dismantling the stator member and / or the entire module. Indeed, the geometries of certain fins, which are very thin, can wear out quickly and require regular replacement. Furthermore, these fins may be mounted on platforms that have complex means of holding them on the radially internal wall and which may cause disturbances in the airflow. Added to this is the fact that the shape of the fins may not be suited to the desired performance or missions and it is impossible to remedy this shape problem. These disadvantages thus affect the performance of the turbomachine.

[0004] There is a need to address some or all of the above drawbacks. Summary of the invention

[0005] The objective of the present invention is to provide a simple, economical and robust solution, which makes it possible to safely and efficiently integrate a fin into a stator member.

[0006] We achieve this objective in accordance with the invention by means of a turbomachine stator member, in particular an aircraft stator member, extending around a longitudinal axis, the stator member comprising at least a first stator vane and at least a second stator vane which are circumferentially adjacent, the first and second stator vanes each comprising a blade extending radially from an annular wall centered on the longitudinal axis, the stator member comprising a fin arranged circumferentially between the first and second stator vanes, the annular wall comprising an imprint of predetermined shape formed in its thickness, open on a radially external surface of the annular wall and at a distance from the upstream and downstream edges of the annular wall, the fin comprising a root, deformed complementary to the imprint, intended to be arranged removably in the imprint,and a fin body which extends radially from the root and which is elongated in a direction of elongation substantially parallel to the longitudinal axis.,

[0007] Thus, this solution makes it possible to achieve the aforementioned objective. In particular, the arrangement of the fins, considered as a passive system, allows an improvement in the operability of the turbomachine by limiting or even eliminating the flow passing between two adjacent stator blades of a stator member. Each fin creates a wall close to the stator blades which blocks the parietal flow coming from the intrados surface of a blade of an adjacent stator blade. The configurations of the footprint and the correspondingly shaped root make it possible to optimize the integration of the fin in the annular wall of the stator organ and secure it in a simple, fast and efficient way. Their configurations also allow each fin to be replaced easily, for example, under the wing, without having to dismantle the complete module, and in particular the entire stator grid. Fins with different shapes can be provided depending on the missions to be carried out, which optimizes the system and makes it more flexible. In addition, replacing the fins allows for economic savings, flexibility in the shape of the fins depending on the desired performance and a reduction in environmental impact.

[0008] The stator member also includes one or more of the following features and / or steps, taken alone or in combination: - the foot extends along an axis of revolution and comprises a separate base and platform connected by a rod along the axis of revolution A. - the base has two ears of identical shape and arranged on either side of the rod in a plane perpendicular to the axis of revolution. - the fin is made from one piece or is formed from assembled single pieces. - the imprint comprises three portions intended to receive respectively one of the elements forming the foot. - the imprint comprises a first portion having a shape corresponding to that of the platform, the platform having an external surface having surface continuity with the radially external surface of the annular wall. - the impression comprises a second portion and a third portion each having a shape similar to that of the base, the third portion having at least one dimension greater than that of the second portion and the base. - the fin includes means for locking the foot in the imprint. - the locking means comprise a locking element arranged in a cavity of the base, the locking element being intended to occupy a locking position and an unlocking position, and an element for retaining the locking element, in its locking position, which is arranged in the imprint. - the locking means comprise a return element mounted in the cavity and intended to permanently urge the locking element towards the locking position. - the imprint comprises at least one groove intended to receive at least in part the locking element in the unlocked position. - the footprint and the root of the fin are configured so that the fin pivots between an inactive position in which the direction of elongation of the fin body is transverse to the longitudinal axis and an active position in which the direction of elongation of the fin body is substantially parallel to the longitudinal axis. - the second portion of the print opens into both the first portion of the print and the third portion of the print.

[0009] The invention relates to a turbomachine, in particular for an aircraft, comprising at least one stator member having any one of the aforementioned characteristics.

[0010] The invention further relates to a method for mounting at least one fin in a stator member as described above. The method comprises the following steps: - positioning of the fin foot by complementary shape in the imprint and in such a way that the direction of elongation of the fin body is transverse to the longitudinal axis, and - rotation of the fin foot around the axis of revolution A in the imprint so as to orient the direction of elongation of the fin body substantially parallel to the longitudinal axis. Brief description of the figures

[0011] The invention will be better understood, and other aims, details, characteristics and advantages thereof will appear more clearly on reading the detailed explanatory description which follows, of embodiments of the invention given as purely illustrative and non-limiting examples, with reference to the appended schematic drawings in which: - Figure 1 is an axial sectional view of an example of a turbomachine to which the invention applies; - Figure 2 is a perspective and detailed view of an example of a stator member comprising stator blades and fins according to the invention; - Figure 3 illustrates in a perspective view an example of a fin intended to be integrated in a removable manner into a stator member according to the invention; - Figure 4 is a perspective view of another embodiment of a fin according to the invention; - Figure 5 represents an example of an imprint made in an annular wall of a stator member according to the invention; - Figure 6 is a detail view of a portion of the print according to Figure 5; - Figure 7 is a perspective view of a step of inserting a fin into an imprint of an annular wall of a stator member according to the invention; - Figure 8 is a perspective view of a step of rotation of a fin in the impression according to Figure 7; - Figure 9 is a perspective view of a fin mounted and fixed between two adjacent stator blades according to the invention; - Figure 10 is a perspective and partial view of a part of a foot of the fin in a portion of an imprint of an annular wall according to the invention; - Figure 11 is a cross-sectional view of an example of a fin fixed in an imprint formed in an annular wall according to the invention; and - Figure 12 represents a flowchart of a method of mounting at least one fin in a stator member according to the invention. Detailed description of the invention

[0012] Figure 1 represents a turbomachine 1 with longitudinal axis X to which the invention applies. The turbomachine 1 is a double-flow and double-spool turbomachine intended to be mounted on an aircraft, such as an airplane. Of course, the invention can be applied to other types of turbomachine, such as a turbofan, a turboprop or a turboshaft engine, and which is shrouded or unshrouded.

[0013] In the present invention, and generally, the terms "upstream" and "downstream" are defined with respect to the circulation of gases or air flows in the turbomachine and here along the longitudinal axis X. The terms "axial" and "axially" are defined with respect to the longitudinal axis X. The terms "external", "exterior", "internal", "internal" and "radial" are defined with respect to a radial axis Z which extends from the longitudinal axis X and with respect to the distance from the longitudinal axis X. The radial axis is perpendicular to the longitudinal axis.

[0014] The turbomachine shown comprises a fan 2 mounted upstream of a gas generator 3 or engine (gas turbine).

[0015] The gas generator 3 comprises, from upstream to downstream, a low-pressure compressor 4, a high-pressure compressor 5, a combustion chamber 6, a high-pressure turbine 7 and a low-pressure turbine 8. Conventionally, the turbomachine 1 comprises a low-pressure shaft (not shown) which connects the low-pressure compressor 4 and the low-pressure turbine 8 to form a body low pressure and a high pressure shaft 10 which connects the high pressure compressor 5 and the high pressure turbine 7 to form a high pressure body. The low pressure shaft, centered on the longitudinal axis X, is intended to drive here a fan shaft (not shown). A power transmission mechanism 11 such as a speed reducer can be interposed between the low pressure shaft and the fan shaft secured to a hub of the fan 2.

[0016] The fan 2 comprises fan blades 12 carried by the hub of longitudinal axis X and surrounded by a fan casing 13 carrying a nacelle (not shown). The fan 2 compresses the air flow which enters the turbomachine 1 and which is divided into a primary flow F1 passing through the gas generator and into a secondary flow F2 circulating around the gas generator 3.

[0017] Each compressor 4, 5 and each turbine 7, 8 comprises several stator stages or stator members comprising stator blades 4a, 5a, 7a, 8a and several rotor stages comprising moving blades 4b, 5b, 7b, 8b along the longitudinal axis X. In the present invention, we understand by the term "stator blade" or "fixed blade", a blade which is not driven in rotation around the longitudinal axis X of the turbomachine. In other words, this stator blade 4a, 5a, 7a, 8a is distinct and contrary to a moving or rotor blade 4b, 5b, 7b, 8b of the turbomachine. The stator blades and the moving blades are arranged in the form of an annular row and the stator blade stages 4a, 5a, 7a, 8a are alternated with the moving blade stages 4b, 5b, 7b, 8b along the longitudinal axis X. The stator blades 4a, 5a, 7a, 8a deflect and straighten the primary flow F1 at the outlet of each moving blade 4b, 5b, 7b, 8b located upstream of them.

[0018] Stator vanes 15 may be arranged downstream of the fan vanes 12 to straighten the secondary flow F2. These stator vanes 15 are called outlet guide vanes and are abbreviated “OGV” for “Outlet Guide Vane” in English. The stator vanes 15 are arranged transversely in the nacelle substantially in a plane transverse to the longitudinal axis X. They are regularly distributed in this exemplary embodiment around the axis X of the turbomachine 1.

[0019] Figure 2 partially represents several stator blades 20 equipping a stator member 21. The stator blades 20 are distributed circumferentially around the longitudinal axis X. The stator blades 20 each comprise a blade 22 which extends substantially radially from an annular wall 23 centered on the longitudinal axis X. The annular wall 23 extends between an upstream edge 24a and an edge downstream 24b along the longitudinal axis X. More precisely, the blade 22 extends radially between a radially inner wall and a radially outer wall (not shown) which are centered on the longitudinal axis X. The radially inner wall and the radially outer wall can be sectorized. In the remainder of the description, we consider that the radially inner wall is the annular wall 23 although the radially outer wall could be the annular wall.

[0020] Each blade 22 extends radially between a root end 22c and a tip end (not shown). Each blade 22 also comprises a pressure surface 22i and an extrados surface 22e extending generally axially along the longitudinal axis X and which are connected upstream by a leading edge 22a and downstream by a trailing edge 22b. The pressure and extrados surfaces are transversely opposite each other. The root end 22c of each blade 22 is secured to the radially inner wall 23. The stator vanes 20 are advantageously identical and are arranged longitudinally in the same way over the entire radially inner wall 23. In particular, the radially inner wall 23 and the blades 22 are monobloc. In other words, the blade 22 and the radially inner wall 23 (or the radially inner wall sector) are made in one piece.

[0021] In Figure 2 which illustrates an example of a stator member 21, at least one fin 25 is arranged between two circumferentially adjacent stator blades 20. A plurality of fins 25 are alternated in this exemplary embodiment with stator blades 20 around the longitudinal axis X. The fins 25 are arranged close to the leading edges 22a of the blades 22 of the stator blades but could be located in any area of ​​the radially inner wall 23 between two adjacent stator blades 20, 20'.

[0022] With reference to Figure 3, each fin 25 comprises a root 26 and a fin body 27 which extends radially from the root 26. Each fin 25 has a height h1 conventionally between 5 and 15% of the height of the stator blades.

[0023] The fin body 27 is elongated in a direction substantially parallel to the longitudinal axis X (in the installation situation). In the example illustrated, the fin body 27 has an aerodynamic profile substantially identical to that of a stator blade 20. This aerodynamic profile makes it possible, on the one hand, to limit the passing vortex flow at the level of the radially internal wall 23 and to control any aerodynamic separations between two adjacent stator blades 20. Of course, the fin body may have a different shape, such as such as a rounded shape that resembles a bump, a symmetrical shape or even a non-axisymmetrical shape. The body of the fin can have various shapes that are adapted to the flow to be controlled and can be more or less steep.

[0024] More precisely, the fin body 27 comprises an upstream edge 27a and a downstream edge 27b which are connected by a lower surface 27i and an upper surface 27e. The fin body 27 has a length L1 measured between the upstream edge 27a and the downstream edge 27b which is less than that of each stator vane blade 20. The length L1 may be between 5 and 70% of the length of the stator vane blades. In particular, the length L1 of the fin body 27 must allow the rotation of the fin 25 between two stator vanes (between an inactive position and an active position) and which will be detailed later. In the present example, the upstream edge 27a of each fin body 27 is offset downstream of the leading edges 22a of the stator vane blades along the longitudinal axis X. This axial offset may be between 0% and 40% of the chord (or chord line) connecting the leading edge 22a to a trailing edge 22b of a stator vane blade 22 20.Alternatively, the upstream edge 27a of each fin body 27 is aligned with the leading edges 22a of the stator vane blades 20.

[0025] The foot 26 is intended to be arranged in a removable manner in an imprint 28 having a predetermined shape and formed in the annular wall 23. The foot 26 of each fin 25 has a complementary shape with the corresponding imprint 28. The fin 25 is therefore configured to be attached and fixed in a removable manner to the stator member 21 and in particular to the radially internal wall 23.

[0026] More precisely, each foot 26 extends along an axis of revolution A. Each foot 26 comprises a base 29 and a platform 30 which are distinct and which are connected by a rod 31 along the axis of revolution A. In other words, the base 29 and the platform 30 are opposite along the axis of revolution A. In the installation situation, the axis of revolution A is parallel to the radial axis Z.

[0027] Advantageously, the rod 31 is cylindrical and has a circular cross-section. The fin body 27 is arranged on the platform 30 and extends radially outward from this platform 30. The latter here has a circular cross-section in order to promote the integration of the fin 25 into the radially internal wall 23 of the stator member 21. In particular, the platform 30 has an external surface 30a and an internal surface 30b which are opposite along the axis of revolution A.

[0028] The platform 30 comprises a border 30c, here circular, connecting the external and internal surfaces 30a, 30b. The fin body 27 rests on the external surface 30a. Advantageously, but not limitingly, the upstream edge 27a and the downstream edge 27b of the fin body 27 are contained in the border 30c of the platform 30. That is to say that the fin body 27 extends inside the border 30c.

[0029] In Figure 4 which shows another embodiment of a fin 25, the fin body 27 which rests on the external surface 30a of the platform 30 extends beyond the edge 30c. In other words, the length L1 of the fin body 27 is greater than the diameter of the platform 30. The foot 26 of this embodiment is similar to that of the previous embodiment.

[0030] Each base 29 has two lugs 32 having an identical shape, called first lug 32a and second lug 32b. The lugs 32a, 32b are arranged on either side of the rod 31 in a plane perpendicular to the axis of revolution A of the rod 31. Each lug 32a, 32b has an external surface 33a and an internal surface 33b which are opposite along the axis of revolution A. The external and internal surfaces 33a, 33b of the lugs 32a, 32b form the internal and external surfaces of the base 29. Each lug 32a, 32b also comprises two abutment surfaces 33c, 33d which extend radially and which are connected by a contact surface 33e. The abutment surfaces 33c, 33d are planar and defined in planes transverse to the planes in which the outer and inner surfaces 33a, 33b are defined. The inner and outer surfaces 33b, 33a are connected by the abutment surfaces 33c, 33d, and the contact surface 33e.

[0031] In the present example, the ears 32a, 32b have a triangular section. The abutment surfaces 33c, 33d are connected on the one hand to the contact surface 33e and on the other hand to a cylindrical external surface 35 of the rod 31. Advantageously, but not limitingly, the contact surface 33e has a curvature. The latter is defined by an arc of a circle whose center is located on the axis of revolution A. The abutment surfaces 33c, 33d form a predetermined angle between them. The predetermined angle can advantageously be between 45° and 80°.

[0032] Advantageously, but not limited to, the fin is made of one piece. In other words, the fin body 27, the platform 30, the rod 31 and the base 29 are formed from a single piece or made of one piece. This makes it possible to simplify the manufacturing and also the implementation of the fin. Alternatively, the fin can be formed from several single pieces, for example the fin body and the foot, which are manufactured separately and subsequently assembled with fixing means such as welding, threaded members, glue, etc.

[0033] Advantageously, but not limitingly, the base 29 comprises a keying element configured so as to allow correct assembly of the base in the imprint 28 and preferably to differentiate the correct mounting direction. The keying element comprises one of the first and second lugs 32a, 32b of the base 29. Indeed, one of the first and second lugs 32a, 32b has at least one dimension greater than that of the other of the first and second lugs to form the keying element. In the present example, the first lug 32a extends along an angular section in the plane perpendicular to the axis of revolution A which is greater than the angular section of the second lug 32b. The imprint 28 has a portion which has a shape complementary to that of the first lug 32a.The keying element may of course alternatively or additionally comprise at least one lug or other element intended to cooperate with another part or portion provided in the imprint 28.

[0034] In Figures 3 and 4, locking means 37 are configured to lock the foot 26 of a fin 25 in the corresponding imprint 28. Preferably, the locking means 37 are self-locking. By the term self-locking, we mean the fact that the locking or unlocking is carried out automatically without human intervention or the implementation of an additional particular accessory acting on the locking means themselves. The rotation of the fin is operated, however, by an operator who is not included in this definition. The locking means 37 comprise a locking element 38 movable between a locking position and an unlocking position. In the present example, the locking element 38 is carried by the foot 26. Alternatively, the locking element 38 is carried by the platform 30 or the rod 31.The locking means 37 comprise at least one retaining element 39 of the locking element 38 in the locking position.

[0035] The locking element 38 is movably mounted in a cavity 40 (shown in dotted lines in FIG. 3) formed in the base 29 of the foot 26. However, the locking element 38 projects from the contact surface 33e of the base 29. The cavity 40 is here substantially cylindrical along an axis B. The axis B is here perpendicular to the axis of revolution A.

[0036] The locking means 37 comprise a return element 41 which is intended to permanently urge the locking element 38 towards the locking position. The return element 41 is mounted in the cavity 40.

[0037] The movable locking element 38 comprises a ball, a rod, a finger, or a similar element. Preferably, the locking element 38 is a ball. The return element 41 is here a compression spring. The latter comprises a first end which is fixed to a bottom 40a of the cavity 40 and a second end which is fixed to the locking element (here the ball).

[0038] The retaining element 39 is arranged in each indentation 28.

[0039] Figure 5 illustrates more precisely a portion of the radially internal wall 23 which comprises at least one imprint 28 formed in the thickness of the wall 23 and which is open on a radially external surface 23a of the wall 23. As can be seen, the imprint 28 is advantageously located at a distance from the upstream and downstream edges 24a, 24b of the annular wall. This makes it possible on the one hand to facilitate the assembly of each fin and on the other hand to avoid parts which would be arranged upstream of the upstream edge 24a of the annular wall or downstream of the downstream edge 24b of the annular wall 23 and which could hinder the assembly or disassembly of each fin 25.

[0040] The imprint 28 has different portions intended to respectively receive the elements forming the foot 26. The different portions are placed along the radial axis Z. In other words, the different portions are arranged at different depths of the thickness of the radially internal wall 23.

[0041] The imprint 28 comprises a first portion 42 which is intended to receive the platform 30 of the foot 26. The first portion 42 comprises a shape similar to that of the platform. Here, the platform 30 and the first portion 42 have a circular section and are of complementary shapes. The platform 30 and the first portion 42 have an identical height (along the radial axis). The first portion 42 comprises a bottom 42a which is defined in a plane perpendicular to the radial axis. A circular wall 42b rises from the bottom 42a (along the radial axis). The height of the first portion 42 is measured from this bottom. In the installation situation, the external surface 30a of the platform 30 has surface continuity with the radially external surface 23a of the radially internal wall 23. The edge 30c of the platform fits the circular wall 42b while allowing rotation of the platform 30 around the axis of revolution A.

[0042] The imprint 28 also comprises a second portion 43 which has a shape corresponding to that of the base 29. In the present example, the second portion 43 is defined by a through opening on either side along the radial axis and delimited by a radial wall 43b. In other words, the second portion 43 opens into the bottom 42a of the first portion 42. More precisely, the second portion 43 has a shape with two parts 44a, 44b which are opposite in a direction defined in a plane perpendicular to the radial axis. This shape is substantially similar to that of an hourglass. The second portion 43 further comprises a central zone 44c whose wall of semicircular cross-section is complementary to the cylindrical surface 31a of the rod 31. Advantageously, but not limitingly, the second portion 43 has a height identical to or less than that of the rod 31.In the present example, the part 44a of the second portion extends over an angular sector greater than that of the second part 44b. The first part 44a can accommodate the first lug of the base and the second part can accommodate the second lug of the base 29. This function of keying elements of the second portion 43 and of the lugs of the base 29 makes it possible to insert the foot 26 into the impression in the correct direction.

[0043] With reference to Figure 6, the imprint 26 finally comprises a third portion 45 which also has a shape corresponding to that of the base 29. The third portion 45 comprises a generally hourglass shape like the second portion 43, i.e. two opposite parts following a direction defined in a plane perpendicular to the radial axis. The second portion 43 opens into the third portion 45. The third portion 45 is intended to receive the base 29 in the installation situation. However, the third portion 45 has a dimension greater than that of the second portion 42 and of the base 29. This allows rotation of the base 29 in the third portion of the imprint 28.

[0044] For this purpose, the third portion 45 has a bottom 45a from which rises a radial wall 45b delimiting the shape thereof. The bottom 45a is defined in a plane perpendicular to the radial axis. The internal surface 33b of the base 29 is intended to rest on the bottom 45a of the third portion 45 of the impression. In the present example, the area of ​​the internal surface 33b of the base is substantially half that of the bottom 45a of the third portion 45 of the impression.

[0045] For each part 46a, 46b making up the third portion 45, the radial wall 45b comprises two opposite sides 47a, 47b which are connected by a curvilinear partition 48. The two parts are connected by a central zone 49 with semi-cylindrical walls. The opposite sides 47a, 47b of each part form a predetermined angle between them. The predetermined angle can advantageously be between 50° and 160°.

[0046] As stated previously, and as can be seen in FIG. 6, the imprint 28 comprises the retaining element 39 of the locking element 38 in its locking position. The retaining element 39 is arranged in the curvilinear partition 48. The retaining element 39 is formed here by a housing whose opening opens into the curvilinear partition 48 at the level of the third potion 45. The housing here has a circular section.

[0047] The imprint 28 further comprises at least one groove intended to receive at least in part the locking element 38 in the unlocked position. In particular, a first groove 50 is arranged in the curvilinear partition 47, in the third portion 45. The first groove 50 has a complementarity with the locking element 38, here the ball, which projects from the base 29, in the unlocked position. In particular, the first groove 50 is arranged at a distance from the housing receiving the locking element 38 in the locked position.

[0048] A second groove 51 is arranged in a circular partition 52 of the second portion 43 and in particular of one of the parts 44a, 44b (here the first part) of the second portion 43. The second groove 51 is advantageously located in a middle zone of the partition 51. The second groove 51 also has a complementary shape with the locking element 38, in particular in the unlocked position.

[0049] We will now describe in detail the method of mounting at least one fin 25 in a corresponding imprint 28 of an annular wall 23 of a stator member 21 of the turbomachine and with the aid of figures 7 to 11. This method is represented in a flowchart in figure 12.

[0050] The method 100 comprises a step 101 of positioning the foot 26 of the fin 25 by shape complementarity in the imprint 28 of the annular wall 23 of the stator member 21. During this positioning, a translation along the radial axis Z is carried out. The radial translation facilitates assembly and avoids possible obstacles for assembly and / or disassembly.

[0051] Prior to placing the foot 26 in the imprint 28, the fin 25 is positioned so that the upstream edge 27a of the fin body 27 is positioned substantially opposite the extrados surface 22e of the blade 22 of the first stator vane 20. In other words, the direction of elongation of the fin body 27 is transverse to the longitudinal axis. This is made possible by the keying elements which are here the difference in size of the ears 32a, 32b of the base 29 and of the second portion 43.

[0052] During installation, the base 29 first passes through the first portion 42 of the imprint then the second portion 43 of the imprint to end up in the third portion 45.

[0053] After the foot 26 has been placed in the impression 28, the fin 25 is in an inactive position where the direction of elongation of the fin body 27 is transverse to the longitudinal axis. More precisely, the internal surface 33b of the base 29 is in contact with the bottom 45a of the third portion 45 of the impression and the internal surface 30b of the platform 30 is in contact with the bottom 42a of the first portion 42 of the impression. The contact surface 33a of each ear 32a, 32b is substantially complementary with the corresponding curvilinear partition 48. The rod 31 extends through the third portion and / or the second portion and in particular at the central zones. The axis of the rod 31 acts as the axis of rotation of the foot in the imprint 28. The locking element 38 (the ball) of the locking means 37 is introduced into the first groove 50. The locking element 38 occupies its unlocking position.The external surface 30a of the platform is flush with the radially external surface 23a of the annular wall 23. The platform 30 is arranged by complementary shape in the first portion 42 of the impression.

[0054] The method 100 comprises a step 102 of rotating the foot 26 of the fin around the axis of revolution A in the imprint 28 so as to orient the direction of elongation of the fin body 27 substantially parallel to the longitudinal axis X. The direction of elongation may have an angular offset with the longitudinal axis of between 5° and 20°. In particular, the fin 25 pivots between the inactive position in which the direction of elongation of the fin body 27 is transverse to the longitudinal axis and an active position in which the direction of elongation of the fin body 27 is substantially parallel to the longitudinal axis X. The rotation of the foot 26 is permitted thanks to the difference in section between the base 29 and the third portion 45 of the imprint. Indeed, the third portion 45 having dimensions (angular sector of each part) greater than those of the base, the latter can easily pivot around the axis of revolution, in the plane of the bottom 45a. This rotation is also facilitated thanks, on the one hand, to the rod 31 which serves as a pivot and which is housed in at least one central zone of the impression 28 of complementary shape and, on the other hand, to the platform 30 housed in the first portion 42 of impression by complementarity of shape. Similarly, the platform 30, the rod 31 and the base 29 being in one piece, the whole assembly pivots around the axis of revolution.

[0055] The rotation angle of the foot is between 40° and 60°. The rotation of the foot 26 is limited by at least one stop. Alternatively, or in addition, the rotation of the foot 26 is limited by the locking means 37, in particular when the locking element is housed in one of the first and second grooves 50, 51 or in the retaining element 39. In the present example, the stop is produced by one of the stop surfaces 47a of the third portion 45 of the impression as illustrated in FIG. 10. In FIG. 10, the fin 25 occupies its active position. The stop surface 33c of the first lug is in plane / plane contact with the face 47a of the first part of the third portion 45 and the stop surface 33d is in plane / plane contact with the face 47b of the second part of the third portion 45. In the case where the rotation is limited by the locking means, the stop surfaces 33c, 33d may be at a distance from the faces 47a, 47b of the imprint 28.

[0056] Following the rotation, the locking element is housed in the housing (forming the retaining element 39) of the third portion 45 provided for this purpose. Indeed, during the rotation of the foot, the ball comes into contact with the curvilinear partition of the third portion 45 of impression, the radius of which here is substantially equal to the radius of an ear, which pushes the ball inside the cavity 40. Once the ball is arranged opposite the housing (each ear is in abutment against a face of the third portion), the ball is returned to its unlocking position by the spring and is introduced into the housing to block the foot 26 of the fin 25 in the corresponding impression 28. We understand that the simple rotation of the fin 25 makes it possible to quickly and effectively lock it in the impression 28 and on the annular wall 23.

[0057] Figure 11 thus illustrates the fin 25 fixed in the annular wall 23 in a removable manner with the ball carried by the foot 26 which is housed in the housing of the imprint 28 and the fin body 27 oriented substantially along the longitudinal axis.

[0058] In this way, the configurations of the foot 26 of the fin 25 and of the imprint 28 make it possible to position the fin 25 precisely, quickly and efficiently in the annular wall 23 of the stator member while ensuring sealing in the wall and facilitating its replacement if it is damaged by wear or breakage thereof or to adapt the shape of the fin body according to a mission. It is sufficient to access the stator member from upstream or downstream to change / mount a fin. Furthermore, in the case of an annular wall sector, the installation of the fin between two adjacent stator blades 20, 20' does not hinder the sealing of the annular wall 23 and can be installed independently of the connection zone between two annular wall sectors.

Claims

Claims [1] Stator member (21) of a turbomachine (1), in particular of an aircraft, extending around a longitudinal axis (X), the stator member (21) comprising at least a first stator vane (20) and at least a second stator vane (20') which are circumferentially adjacent, the first and second stator vanes (20, 20') each comprising a blade (22) extending radially from an annular wall (23) centered on the longitudinal axis (X), the stator member (21) comprising a fin (25) arranged circumferentially between the first and second stator vanes (20, 20'), characterized in that the annular wall (23) comprises an imprint (28) of predetermined shape formed in its thickness, open on a radially external surface (23a) of the annular wall and at a distance from the edges upstream and downstream (24a, 25b) of the annular wall (23), the fin (25) comprising a foot (26), of a shape complementary to the imprint (28),intended to be arranged removably in the imprint (28), and a fin body (27) which extends radially from the foot (26) and which is elongated in a direction of elongation substantially parallel to the longitudinal axis (X)., [2] Stator member (21) according to the preceding claim, characterized in that the foot (26) extends along an axis of revolution (A) and comprises a base (29) and a separate platform (30) connected by a rod (31) along the axis of revolution A. [3] Stator member (21) according to the preceding claim, characterized in that the base (29) has two ears (32a, 32b) of identical shape and arranged on either side of the rod (31) in a plane perpendicular to the axis of revolution (A). [4] Stator member (21) according to one of the preceding claims, characterized in that the fin (25) is made in one piece or is formed from assembled single-piece parts. [5] Stator member (21) according to one of claims 2 to 4, characterized in that the imprint (28) comprises three portions (42, 43, 45) intended to receive respectively one of the elements forming the foot (26). [6] Stator member (21) according to one of claims 2 to 5, characterized in that the imprint (28) comprises a first portion (42) having a shape corresponding to that of the platform (30), the platform (30) having an external surface (30b) having surface continuity with the radially external surface (23a) of the annular wall (23). [7] Stator member (21) according to one of the preceding claims, characterized in that the imprint (28) comprises a second portion (43) and a third portion (45) each having a shape similar to that of the base (29), the third portion (45) having at least one dimension greater than that of the second portion (43) and of the base (29). [8] Stator member (21) according to one of the preceding claims, characterized in that the fin (25) comprises means (37) for locking the foot (26) in the imprint (28). [9] Stator member (21) according to one of the preceding claims, characterized in that the locking means (37) comprise a locking element (38) arranged in a cavity (40) of the base (29), the locking element (38) being intended to occupy a locking position and an unlocking position, and a retaining element (39) of the locking element (38) in its locking position which is arranged in the imprint (28). [10] Stator member (21) according to the preceding claim, characterized in that the locking means (37) comprise a return element (41) mounted in the cavity (40) and intended to permanently urge the locking element towards the locking position. [11] Stator member according to one of claims 9 and 10, characterized in that the imprint (28) comprises at least one groove (50, 51) intended to receive at least in part the locking element (38) in the unlocked position. [12] Turbomachine (1), in particular for an aircraft, comprising at least one stator member (21) according to any one of the preceding claims. [13] Method (100) for mounting at least one fin in a stator member according to any one of claims 1 to 11, the method comprising the following steps: positioning (101) the root (26) of the fin (25) by form complementarity in the imprint (26) and in such a way that the direction of elongation of the fin body (27) is transverse to the longitudinal axis (X), and rotation (102) of the root (26) of the fin around the axis of revolution (A) in the imprint (28) so as to orient the direction of elongation of the fin body (27) substantially parallel to the longitudinal axis (X).

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