Stator vane for an inlet stator of an aircraft turbine engine, method for manufacturing a stator vane for an inlet stator of an aircraft turbine engine, and turbine engine for an aircraft

Abstract

The invention relates to a stator vane (20) for an inlet stator of an aircraft turbine engine (1), the stator vane comprising a blade (22). The blade is rigidly connected to an inner platform (26) and to an outer platform (30). The blade has a leading edge (224) and a trailing edge (226) extending between the inner and outer platforms. The stator vane comprises a main body (34) and an insert (36) partially confined within the main body (34). A central portion (360) of the insert forms a part of the blade and comprises at least the leading edge. The insert has first and second end portions (362; 364) between which the central portion (360) extends. Each end portion is confined in a first and second end portion (342; 344) of the main body, respectively. A central portion (340) of the main body extends between the two end portions to form the rest of the blade. The stator vane is obtained by overmolding the main body onto the insert. The turbine engine comprises at least one such stator vane. A method for manufacturing a stator vane comprises a step of manufacturing an insert and a step of overmolding a main body onto the insert.

Description

Technical Field

[0001] This invention relates to the field of aviation. More specifically, it relates to stator vanes for aircraft turbines, and more particularly to, for example, inlet stator vanes or compressor stator vanes for low-pressure compressors. Background Technology

[0002] Turbines used for aircraft propulsion include gas generators. Specifically, the gas generator comprises a stator, a low-pressure compressor, and a high-pressure compressor, arranged from upstream to downstream relative to the gas flow direction.

[0003] The stator and compressor include blades designed to operate in harsh environments and are particularly susceptible to mechanical shocks, such as from foreign objects being sucked into the turbine (e.g., birds or hail). Blades are also prone to icing, which can be problematic if the ice is broken up and propelled downstream within the turbine. This often leads to limited gas flow rates within the turbine, or even damage to the turbine itself.

[0004] Due to the aforementioned thermal and mechanical constraints, material selection in blade design is precise, as it ideally requires materials with both high mechanical strength and high thermal conductivity (to facilitate the operation of de-icing and anti-icing systems when appropriate), while also allowing for the production of blades with the lowest possible mass. Therefore, it is difficult to find materials that excel in both mechanical strength, thermal conductivity, and lightweight. For example, titanium alloys, frequently used in aerospace, offer a very good trade-off between mechanical strength and lightness, but have relatively low thermal conductivity.

[0005] The object of this invention is to provide a turbine stator vane that overcomes the disadvantages of the prior art, particularly those mentioned above. Summary of the Invention

[0006] Therefore, the present invention relates to a stator vane for an aircraft turbine, particularly an inlet stator vane, the vane comprising a blade fixed at a first end to an inner platform and at a second end opposite to the first end to an outer platform, the blade including a leading edge and a trailing edge extending between the inner and outer platforms respectively, the blade including a pressure side and a suction side extending from the leading edge to the trailing edge; the vane including a body and an insert partially embedded in the body, the central portion of the insert forming a portion of the blade, the portion including at least the leading edge, the insert including first and second ends, the central portion of the insert extending between the first and second ends, each end being embedded in the first and second ends of the body respectively, the central portion of the body extending between the two ends to form the remainder of the blade.

[0007] Therefore, by providing a stator blade that includes an insert forming the leading edge of the stator blade (as well as more or less significant portions of the suction and pressure sides), the remaining portion of the blade is formed by a body in which the insert is partially embedded. The insert and body can be easily designed from different materials. Thus, when selecting a material to form the leading edge, mechanical strength and thermal conductivity can be advantageous, while when selecting a material to form the body, mechanical strength and light weight can be advantageous. The body may represent the main part of the entire stator blade. By providing an insert partially embedded in the body, a robust connection between the body and the insert is ensured when the materials forming the body and the insert are different, and especially when they exhibit significant differences in thermal expansion.

[0008] The stationary blade according to the invention may include one or more of the following optional features, either individually or in any possible combination.

[0009] According to one feature, the inner platform is formed by a first end of the body and a first end of the insert, and the outer platform is formed by a second end of the body and a second end of the insert.

[0010] According to one characteristic, the stationary blade is of the variable pitch type and includes an inner pivot fixed to the inner platform and an outer pivot fixed to the outer platform.

[0011] According to one feature, the first end of the insert and / or the second end of the insert have a generally annular shape, which has an axis parallel to the axis of rotation defined by the pivot.

[0012] According to one characteristic, the still blade is a hollow still blade, the blade including an inner cavity that is partially defined by the central portion of the body and partially defined by the central portion of the insert.

[0013] According to one feature, the central portion of the insert includes a pressure side portion that forms a portion of the pressure side of the blade and a suction side portion that forms a portion of the suction side of the blade.

[0014] According to one characteristic, the length of the pressure-side portion and / or suction-side portion extending from the leading edge is less than or equal to 20% of the blade's chord length, for example, included between 5% and 10% of the chord length.

[0015] According to one characteristic, the length of the pressure-side portion and / or suction-side portion extending from the leading edge is greater than or equal to 10% of the blade chord length, for example, included between 10% and 25% of the chord length.

[0016] According to one feature, the stator is a solid stator, wherein the pressure-side portion and / or suction-side portion includes a retaining element having a shape that facilitates mutual retention between the insert and the body, for example, the retaining element has a dovetail shape.

[0017] According to one feature, the insert is made of a first material, and the body is made of a second material different from the first material.

[0018] According to one feature, the insert is made of steel, preferably steel with a thermal conductivity greater than or equal to 10 W / m / K.

[0019] According to one characteristic, the body is made of a titanium-based alloy or an aluminum-based alloy.

[0020] According to one feature, the still leaf is obtained by molding the body overlay onto the insert.

[0021] The present invention also relates to a method for manufacturing stator vanes as defined above, the method comprising: - Steps for manufacturing the insert; - The step of molding the body onto the insert.

[0022] According to one feature of this method, the insert is made of a material whose melting point is higher than that of the material of the molded body.

[0023] The present invention also relates to an aircraft turbine comprising at least one stator blade as defined above. Attached Figure Description

[0024] Figure 1 This is a schematic cross-sectional view of an aircraft turbine according to the present invention.

[0025] Figure 2 This is a schematic side view of the stilling blade according to the present invention.

[0026] Figure 3 yes Figure 2 A perspective view of the still leaves.

[0027] Figure 4 It is similar to Figure 2 The view shows the insert visible through the still leaf.

[0028] Figure 5 yes Figure 2 The cross-sectional view of the stationary blade along plane AA.

[0029] Figure 6 This is a perspective view of the first embodiment of the insert.

[0030] Figure 7 yes Figure 2 The stationary blade is along the cross section of plane BB.

[0031] Figure 8 This is a perspective view of the insert according to the second embodiment.

[0032] Figure 9 It is similar to Figure 7 The view shows including Figure 8 inserts Figure 2 The quiet leaves.

[0033] Figure 10 It is similar to Figure 5 The view shows a second embodiment of the blade.

[0034] Figure 11 It is similar to Figure 5 The view shows a third embodiment of the blade. Detailed Implementation

[0035] Figure 1 An aircraft turbine 1 according to the invention is shown, in this example a dual-flow turbojet engine (shown without the nacelle typically associated with it). The turbine 1 includes an air inlet 2 through which airflow enters the turbine. The airflow is accelerated by a fan 3. Downstream of the fan 3, the airflow is divided into a main airflow flowing in an inner annular duct 4 or a main duct 4, and a secondary airflow flowing in an outer annular duct 5 or a secondary duct 5 surrounding the inner annular duct 4. In the main duct 4, the main airflow continuously passes through an inlet stator 6 and a gas generator. In this example, the gas generator, from upstream to downstream (relative to the direction of the airflow), includes a low-pressure compressor 7, a high-pressure compressor 8, a combustion chamber 9, a high-pressure turbine 10 and a low-pressure turbine 11, and an exhaust casing 12 to which an exhaust nozzle (not shown) is connected. The secondary duct 5 is partially defined by a fan casing 13 surrounding the fan 3 and a nacelle surrounding the turbine (not shown).

[0036] The inlet stator 6 includes inlet guide vanes (commonly referred to as IGVs). Low-pressure and high-pressure compressors also include stator stators or rectifier stators. Stator stators are fixed stators, typically variable pitch stators (commonly referred to as VSVs).

[0037] Figures 2 to 4 A vane 20 according to the invention is shown, which can be used, for example, as a stator vane in the inlet stator 6 or in one of the compressors 7 and 8.

[0038] In the example shown in the figure, stator 20 is a variable pitch stator. A variable pitch stator can be actuated during turbine operation, causing the stator to pivot about a radial axis of rotation relative to the engine's main axis XX. This pivoting allows for changes in the angle of attack (or stagger angle) of the stator relative to the airflow from the upstream end of the turbine, particularly adapting this angle to different phases of flight of the aircraft.

[0039] Figure 2 and 3The stator blade 20 is shown in side and perspective views, respectively. The stator blade 20 includes a blade 22 having a first radially inner end 220 or blade root 220 and a second radially outer end 222 or blade tip 222. The blade 22 extends successively at its first end 220 from an inner platform 26 and an inner pivot 28, and at its second end 222 from an outer platform 30 and an outer pivot 32. The terms "outer" and "inner" are used in this application to refer to the radially outer and radially inner components of the stator blade 20, respectively, relative to the turbine's main axis XX and relative to the stator blade's normal operating position in the turbine.

[0040] The stationary blade 20 is configured to pivot about a rotation axis YY that coincides with the central axis of the inner pivot 28 and the outer pivot 32, and this rotation is ensured by an actuating member not shown in the figure.

[0041] Pivots 28 and 32 each have a straight cylindrical shape with a circular base. Platforms 26 and 30 have a straight cylindrical shape, with a circular base in the example shown.

[0042] The blade 22 has a leading edge 224 and a trailing edge 226. The leading edge 224 and trailing edge 226 each extend from the inner platform 26 to the outer platform 30. The blade 22 also includes a pressure side 230 and a suction side 232, each extending between the leading edge 224 and the trailing edge 226 (see...). Figure 5 ).

[0043] According to the present invention, the stationary blade 20 includes a body 34 and an insert 36. The insert 36 includes a central portion 360 forming the leading edge 224 of the blade 22, as well as a portion of the pressure side 230 and a portion of the suction side 232.

[0044] The body 34 includes a central portion 340 that partially forms the blade 22. The central portion 340 of the body 34 forms the main portion of the blade 22, and more precisely, forms the entire blade except for the blade portion formed by the central portion of the insert 36, that is, at least the leading edge 224. Therefore, the external shape of the central portion 340 corresponds to the external shape of the blade 22 minus the external shape of the insert. The body 34 includes a first end 342 or inner end forming the main portion of the inner platform 26, and a second end 344 or outer end forming the main portion of the outer platform 30 of the stator blade. The body 34 also forms the pivots 28, 32 of the stator blade 20.

[0045] like Figure 4 As shown, it illustrates the entire insert 36 through a transparent material, and Figure 6 The diagram shows the insert 36 in perspective only. The insert 36 includes a first end 362 or inner end and a second end 364 or outer end. The first end 362 and the second end 364 are respectively fixed to opposite ends of the central portion 360 of the insert 36.

[0046] like Figure 4 As shown, each end 362, 364 of the insert 36 is embedded in the corresponding end 342, 344 of the body 34. Therefore, the insert 36 is partially embedded in the body 34, and the central portion of the insert 36 forming the leading edge 224 of the stator blade is not embedded in the body 34.

[0047] The aforementioned construction of the stator blade 20 allows the insert 36 to be designed using a material different from that used to manufacture the body 34. Specifically, the selection of the material forming the insert 36 (and therefore its leading edge) can benefit mechanical strength and thermal conductivity, while the selection of the material forming the body 34 can benefit mechanical strength and lightweight properties; the body may represent the main part of the entire stator blade. By providing an insert 36 partially embedded within the body 34, a robust connection between the body and the insert is ensured when the materials forming the body and the insert are different, and particularly when they exhibit significant differences in thermal expansion.

[0048] The insert 36 may be made of steel, for example, and particularly of steel having a thermal conductivity greater than or equal to 10 W / m / K. The body 34 may be made of titanium alloy or aluminum alloy, for example.

[0049] In one embodiment, the stationary blade 20 is a hollow stationary blade. Therefore, as... Figure 5 As shown, it illustrates Figure 2 The stationary blade 20 has a cross-section along plane AA, and the blade 22 of the stationary blade 20 includes an inner cavity 228. In this example, the inner cavity 228 is partially defined by the central portion 340 of the body 34 and partially by the central portion 360 of the insert 36. The central portion of the insert 36 thus has a hollow cross-section, which restricts its mass and thereby facilitates de-icing of the leading edge of the blade 22.

[0050] like Figure 6 As can be seen, the first and / or second ends 362, 364 of the insert 36 may have a generally annular shape, thereby defining a central cavity 362a, 364a. This configuration limits the mass of the insert 36 and further facilitates retaining the insert within the body 34.

[0051] Figure 7 It is Jingye 20 along Figure 2 The sectional view of axis BB, therefore including Figure 6 The insert. It can be seen that the outer end 364 of the insert 36 is embedded in the outer end 344 of the main body 34.

[0052] As in Figure 8 and 9 As can be seen in it, it is similar to Figure 6 and 7In the view, one or both of the ends 362, 364 of the insert 36 may not have a generally annular shape, but rather an open shape, which in this example is a generally bow-shaped shape.

[0053] like Figure 10 As shown, it exhibits a similar pattern. Figure 5 In the cross-sectional view of the blade 22 in the figure, regardless of whether the stator blade 20 is hollow or solid, the central portion 360 of the insert 36 can be shaped such that the pressure-side portion 366 of the central portion 360 forming a part of the pressure side of the blade 22 has a different length than the length of the suction-side portion 368 of the central portion 360 forming a part of the suction side of the blade 22. Figure 10 In the example, the pressure side is longer than the suction side.

[0054] To limit the mass of the insert 36, the length of the pressure side portion 366 and / or the length of the suction side portion 368 is less than 20% of the chord length of the blade 22, and for example, between 5% and 10% of that chord length.

[0055] like Figure 11 As shown, it illustrates the relationship with Figure 10 The view shown is a cross-sectional view of a blade 22, which may be solid. Furthermore, the central portion of the insert 36 may be configured such that a portion thereof, in this example, the pressure-side portion 366, extends at least 10% of the chord length of the blade.

[0056] exist Figure 11 In the example, the pressure-side portion 366 extends at least approximately 25% of the chord length. Furthermore, as... Figure 11 As shown, the pressure-side portion 366 or the suction-side portion 368 may include a retaining element 370, the shape of which facilitates mutual retention between the insert 36 and the body 34. In this example, the pressure-side portion 366 includes a retaining element 370 with a dovetail shape.

[0057] The main steps for manufacturing the stationary blades according to the present invention when producing stationary blades by molding are described below.

[0058] The method includes a first step of manufacturing the insert 36, for example, by molding and / or forming and / or machining. The insert is made of a material having mechanical strength suitable for enabling the stator to withstand various mechanical stresses, particularly due to impacts from foreign objects. As mentioned above, the insert 36 is made of steel, for example, and particularly of steel having a thermal conductivity greater than or equal to 10 W / m / K.

[0059] The method then includes the step of overmolding the body 34 onto the insert 36. During the overmolding step, the insert 36 is first placed in a mold having a cavity capable of molding the body 34. The body 34 is then overmolded onto the insert 36 to obtain the stator 20 as described in this specification. In particular, as already described, the overmolding step ensures that the end of the insert 36 is embedded within the body 34. As previously mentioned, the body 34 is made of a material that provides a good trade-off between lightweight and mechanical strength, such as a titanium-based alloy or an aluminum-based alloy.

[0060] In order to produce the stator blade 22 by covering the molded insert 36, the insert 36 is made of a material with a melting point higher than that of the material of the molded body 34.

Claims

1. A stator vane (20) for an inlet stator (6) of an aircraft turbine (1), the stator vane (20) comprising a blade (22) fixed at a first end (222) to an inner platform (26) and at a second end (224) opposite to the first end (222) to an outer platform (30), the blade (22) comprising a leading edge (224) and a trailing edge (226) extending between the inner platform (26) and the outer platform (30), the blade (22) comprising a pressure side (230) and a suction side (232) extending from the leading edge (224) to the trailing edge (226); the stator vane (20) comprising a body (34) and partially embedded therein. The insert (36) in (34) has a central portion (360) forming part of the blade (22), including at least the leading edge (224), the insert (36) including first and second ends (362; 364), the central portion (360) of the insert (36) extending between the first and second ends, each end (362; 364) being embedded in the first and second ends (342; 344) of the body (34), the central portion (340) of the body (34) extending between the two ends (342; 344) to form the remainder of the blade (22), the stator blade (20) being obtained by overmolding the body (34) onto the insert (36).

2. The stator stationary blade (20) according to claim 1, wherein, The inner platform (26) is formed by the first end (342) of the body (34) and the first end (362) of the insert (36), and the outer platform (30) is formed by the second end (344) of the body (34) and the second end (364) of the insert (36).

3. The stator stationary blade (20) according to claim 1 or 2, wherein the stator stationary blade is of the variable pitch type and includes an inner pivot (28) fixed to the inner platform (26) and an outer pivot (32) fixed to the outer platform (30).

4. The stator leaf (20) according to claim 3, wherein the first end (362) of the insert (36) and / or the second end (364) of the insert (36) have a generally annular shape having an axis parallel to the axis of rotation (YY) defined by the inner pivot (28) and the outer pivot (32).

5. The stator stationary blade (20) according to claim 1 or 2, wherein, The stator blade (20) is a hollow blade, and the blade (22) includes an inner cavity (228) that is partially defined by the central portion (340) of the body (34) and partially defined by the central portion (360) of the insert (36).

6. The stator stationary blade (20) according to claim 1 or 2, wherein, The central portion (360) of the insert (36) includes a pressure side portion (366) forming a part of the pressure side (230) of the blade (22) and a suction side portion (368) forming a part of the suction side (232) of the blade (22).

7. The stator stationary blade (20) according to claim 6, wherein, The length of the pressure side portion (366) and / or the suction side portion (368) extending from the leading edge (224) is less than or equal to 20% of the chord length of the blade (22).

8. The stator leaf (20) according to claim 7, wherein, The length of the pressure side portion (366) and / or the suction side portion (368) extending from the leading edge (224) is between 5% and 10% of the chord length.

9. The stator stationary blade (20) according to claim 6, wherein, The length of the pressure side portion (366) and / or the suction side portion (368) extending from the leading edge (224) is greater than or equal to 10% of the chord length of the blade (22).

10. The stator stationary blade (20) according to claim 9, wherein, The length of the pressure side portion (366) and / or the suction side portion (368) extending from the leading edge (224) is between 10% and 25% of the chord length.

11. The stator vane (20) according to claim 1 or 2, wherein the stator vane (20) is a solid vane, wherein the pressure side portion (366) and / or the suction side portion (368) includes a retaining element (370) having a shape that facilitates mutual retention between the insert (36) and the body (34).

12. The stator stationary blade (20) according to claim 11, wherein, The retaining element (370) has a dovetail shape.

13. The stator leaf (20) according to claim 1 or 2, wherein the insert (36) is made of a first material and the body (34) is made of a second material different from the first material.

14. The stator vane (20) according to claim 13, wherein the insert (36) is made of steel.

15. The stator vane (20) according to claim 14, wherein the insert (36) is made of steel having a thermal conductivity greater than or equal to 10 W / m / K.

16. The stator stationary blade (20) according to claim 13, wherein, The main body (34) is made of titanium-based alloy or aluminum-based alloy.

17. A method for manufacturing stator vanes (20) according to any one of claims 1 to 16, the method comprising: - The step of manufacturing the insert (36); The step of overmolding the body (34) onto the insert (36).

18. The manufacturing method according to claim 17, wherein, The insert (36) is made of a material with a melting point higher than that of the material used to mold the body (34).

19. An aircraft turbine (1) comprising at least one stator blade (20) according to any one of claims 1 to 16.

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