Turbine rotating assembly including annular clamping components

Abstract

A turbine rotating assembly is disclosed, comprising a rotor and a stator. The rotor includes at least two consecutive rotor stages (20a, 20b) and an annular rotor collar (30). The consecutive rotor stages (20a, 20b) are provided with a plurality of movable blades. The annular rotor collar connects the two consecutive rotor stages (20a, 20b). The stator has at least one stator stage (10) disposed between the two consecutive rotor stages (20a, 20b), including a plurality of fixed blades (13), a turbine stator blade root (11), an annular clamping member (50), and a wear-resistant annular support member (40). The root (11) extends radially and is axially clamped between the annular wear-resistant support member (40), and a space (12) separates the radially inner end of the root (11) from the annular wear-resistant support member (40). A turbojet engine (100) includes the rotating assembly as described above.

Description

Technical Field

[0001] This disclosure relates to a turbine assembly, such as a turbine or compressor, wherein a radial clearance is established during operation between a stator component (stationary component) fixed to a turbine housing and a rotor component (moving component) rotatably fixed within the housing. This disclosure focuses primarily on the field of aircraft turbojet engines, but can be more generally applied to any type of turbine. Background Technology

[0002] In a turbine, the rotor is driven by air in a flow path that expands at the height of the rotor blades, thus providing some of its energy to the rotor. However, it is often observed that a portion of the air in the flow path, commonly referred to as the "bypass," bypasses the inner and outer plateaus of the blades and therefore does not expand at the height of the blades, which reduces the turbine's performance.

[0003] To limit this inefficient air circulation that bypasses the blades, rotor blade tips are typically equipped with wipers adapted to cut the path of the wear-resistant material carried by the stator, thus ensuring a seal of the flow path at the blade tip. A similar device is provided for vanes (or distributors): in effect, a shroud called a "labyrinth" shroud is placed between the two vanes, carrying wipers adapted to cut the path of the wear-resistant material carried at the vane root, thus ensuring a seal of the flow path at the vane root.

[0004] However, for the system to be effective, it is important to minimize the radial clearance between the separator and the wear-resistant material. However, the high and uneven temperatures prevalent in turbines can cause differential expansion of some components, altering the clearances between parts, particularly those made of different materials or located more or less near the airflow path, thus subjecting them to varying degrees of high temperatures. For example, the radial displacement of the labyrinth shroud is lower than that of the impeller blades, especially at the root: therefore, a clearance is observed separating the separator carried by the labyrinth shroud from the wear-resistant material carried at the root, with the root expanding differently from the wear-resistant material. Consequently, bypass circulation increases, and turbine performance decreases.

[0005] One drawback of current turbines is that differential expansion between labyrinthine shields or annular supports carrying wear-resistant materials and the components mounted on them (here, the root) generates significant mechanical stress at the interfaces between these components, leading to premature damage and thus shortening their lifespan.

[0006] Therefore, there is indeed a need for a rotating component for turbines that is at least partially free from the inherent defects of the aforementioned known constructions. Summary of the Invention

[0007] This disclosure relates to a rotating assembly for a turbine, comprising: a rotor including: at least two consecutive rotor stages having a plurality of blades; and an annular rotor shroud connecting the two consecutive rotor stages; and a stator including: at least one stator stage disposed between the two consecutive rotor stages each having a plurality of blades, each stator stage including a turbine stator blade root, an annular clamping member, and an annular support member of wear-resistant material, the root extending radially and axially clamped between the annular support member and the annular clamping member, wherein the radially inner end of the root and the annular support member of wear-resistant material are spatially radially separated.

[0008] In this disclosure, the axial direction corresponds to the direction of the rotation axis A of the turbojet engine (or fan disk), and the radial direction is the direction perpendicular to axis A. The azimuth direction corresponds to the direction describing the loop around the axial direction. The three axial, radial, and azimuth directions correspond to directions defined by sides, radii, and angles in a cylindrical coordinate system, respectively. Furthermore, upstream and downstream are defined with respect to the normal flow direction of fluid through the turbojet engine (from upstream to downstream).

[0009] In this application, upstream and downstream are defined with respect to the normal flow direction of fluid through the turbojet engine (from upstream to downstream). Furthermore, the axial direction corresponds to the direction of the fan disk's axis of rotation A, while the radial direction is perpendicular to axis A. Finally, unless otherwise specified, the adjectives "inner" and "outer" refer to the radial direction, such that the inner (i.e., radially inner) portion of the element is closer to axis A than the outer (i.e., radially outer) portion of the same element.

[0010] Therefore, the root can expand freely in the radial direction, taking advantage of the space separating its radially inner end from the annular support of the wear-resistant material. In fact, the clearance provided by this space allows the root to expand freely, as well as the annular support of the wear-resistant material, thus allowing for radial self-adjusting expansion of the different components of the stator stage. This, in turn, improves the seal between the two rotor stages.

[0011] Furthermore, because this space allows for free radial expansion of the root, radial contact between the root and the wear-resistant annular support is prevented, thus eliminating radial stress exerted from the root on the wear-resistant annular support. This improves the lifespan of all components in the stator stage.

[0012] Furthermore, the use of clamping components allows for the simple assembly of the annular support for wear-resistant material onto the root. Moreover, the manufacture of such clamping components is simpler than that of prior art devices known, for example, FR 3027343, for securing annular supports for wear-resistant material to the root.

[0013] It should also be noted that this disclosure focuses more on low-pressure turbines, but it can also be applied to high-pressure turbines or compressors.

[0014] In some embodiments, the clamping member is a ring, distinct from the ring support made of wear-resistant material.

[0015] In this design, the manufacturing of the clamping components is independent of the manufacturing of the wear-resistant material support components. Therefore, the manufacturing of the clamping components is simplified.

[0016] In some configurations, the stator stage comprises multiple sections, each of which includes at least one blade extending from the root.

[0017] In some embodiments, the annular support member of the wear-resistant material includes a wear-resistant portion facing at least one wiper carried by the rotor shroud.

[0018] In this configuration, the sealing between rotor stages is better than when the configuration is reversed, i.e., when the rotor shroud includes a wear-resistant portion and the support member carried by the root includes a wiper.

[0019] In some embodiments, the wear-resistant annular support is made of ceramic matrix composite material.

[0020] This material is lighter than metal, has better heat resistance, and a lower coefficient of thermal expansion. Therefore, the expansion of the annular support component made of wear-resistant material is reduced.

[0021] In some embodiments, the root includes a notch configured to engage with a protrusion disposed in an annular support member of a wear-resistant material.

[0022] In this configuration, the tangential movement of the annular support member made of wear-resistant material relative to the root is restricted. It should also be noted that this protrusion only restricts tangential movement: radial movement, especially radial movement due to expansion, is not restricted.

[0023] In some embodiments, the annular support member of the wear-resistant material includes three protrusions distributed at 120° intervals on the annular support member of the wear-resistant material.

[0024] In this structure, the wear-resistant material support is easily centered. In fact, the entanglement of the wear-resistant material ring support at the root helps to position the wear-resistant material ring support, making it concentric with the root.

[0025] In some embodiments, the wear-resistant material annular support includes a threaded portion, and the clamping member is configured to screw onto the wear-resistant material annular support.

[0026] This construction allows for the simple assembly of clamping components and a ring-shaped support made of wear-resistant material around the root.

[0027] In some embodiments, a ring-shaped support member consisting of a clamping component and a wear-resistant material is assembled around the root by shrink fitting.

[0028] In some embodiments, a ring-shaped support member is assembled around the root by welding a clamping component and a wear-resistant material.

[0029] The aforementioned two configurations allow for the alternative assembly of clamping components and wear-resistant material ring supports around the root.

[0030] The present invention also relates to a turbojet engine comprising a rotating component according to any one of the preceding claims.

[0031] This turbojet engine has the aforementioned advantages. Attached Figure Description

[0032] A better understanding of the invention and its advantages will be gained by reading the following detailed description of various embodiments of the invention, given with the aid of non-limiting examples. This description refers to the accompanying drawings, in which:

[0033] [ Figure 1 ] Figure 1 A turbojet engine including a low-pressure turbine is shown according to one embodiment.

[0034] [ Figure 2 ] Figure 2 A cross-sectional view of a low-pressure turbine according to this embodiment is shown.

[0035] [ Figure 3 ] Figure 3 A view centered on the stator root of the low-pressure turbine is shown, with clamping components omitted.

[0036] [ Figure 4 ] Figure 4 Corresponding to Figure 3 A view cut at the horizontal plane of plane IV. Detailed Implementation

[0037] Figure 1 A cross-sectional view is shown along a vertical plane passing through the main axis A of the turbojet engine 100 according to the invention. The turbojet engine 100 includes a fan 2, a low-pressure compressor 300, a high-pressure compressor 400, a combustion chamber 500, a high-pressure turbine 600, and a low-pressure turbine 700.

[0038] Figure 2 A cross-sectional view of a portion of a low-pressure turbine 700 according to an embodiment of the present invention is shown along the same axial plane. The low-pressure turbine 700 includes multiple rotor stages. Figure 2Two consecutive rotor stages 20a and 20b are shown surrounding stator stage 10 from upstream to downstream, with rotor stages 20a and 20b located upstream and downstream of stator stage 10, respectively. Each of these rotor stages 20a, 20b and stator stage 10 includes multiple blades and impellers.

[0039] Each rotor stage 20a, 20b includes a corresponding distributor 21a, 21b, on which blades are disposed. The distributors 21a, 21b of two consecutive rotor stages are interconnected by a shroud 30 including a plurality of wipers 31.

[0040] The stator stage 10 includes multiple sections, each section including one or more blades 13 disposed on a stator blade root 11. The root 11 extends in a radial direction, and the group of roots 11 of each section of the stator stage 10 extends about the axis A of the turbojet engine 100. In other words, the group of roots 11 extends in a plane perpendicular to the axis A.

[0041] The stator stage 10 also includes an annular support 40 of wear-resistant material extending about axis A and axially extending downstream and upstream of the root 11. The annular support 40 of wear-resistant material includes a wear-resistant portion 41 disposed facing a wiper 31 of the shroud 30. The wiper 31 contacts the annular support 40, which obstructs airflow at the level of the root 11 of the stator stage 10. Therefore, air preferably flows at the level of the stator stage blades 13.

[0042] The wear-resistant portion 41 is provided by a material with a honeycomb structure, such as an aluminum alloy. This wear-resistant portion is configured to wear down upon contact with the wiper 31 during the use of the turbojet engine 100.

[0043] The wear-resistant ring support is itself made of 3D braided ceramic matrix composite (CMC) material using a weaving method called "braid profile". "Braid profile" is a known technique for weaving fibrous fabrics with axisymmetric shapes, in which the fiber structure is woven on a mandrel using warp yarns, and the mandrel has an outer profile defined by the profile of the fabric fibers to be manufactured.

[0044] The shield 30 can also be made of 3D woven CMC. This construction is also advantageous because it allows the shield 30 and the annular support 40 of the abrasion-resistant material to expand in the same manner.

[0045] The annular support 40 of the wear-resistant material also includes an arm 42 extending in a radial direction. The arm 42 is located upstream of and extends parallel to the root 11. The annular support 40 of the wear-resistant material also includes a first clamping portion 42a extending axially and located at the radially outer end of the arm 42. The clamping portion 42a is in axial contact with the root 11. In this example, the contact with the root 11 is only axial via the clamping portion 42a.

[0046] A clamping member 50, separate from the annular support member 40 of the wear-resistant material, is disposed downstream of the root 11 and includes a body 52 extending radially parallel to the root 11 and the arm 42. The clamping member 50 includes an axially extending base 51 disposed at the radially inner end of the body 52. ​​The base 51 of the clamping member 50 is in radial contact with the annular support member 40 of the wear-resistant material on the downstream side of the root 11.

[0047] The clamping member 50 also includes a second clamping portion 50a, which is disposed at the radially outer end of the main body 52. ​​The second clamping portion 50a is in axial contact with the root portion 11 and is configured to face the first clamping portion 42a. The two clamping portions 42a and 50a generate axial forces on the root portion 11 in opposite directions, so that the root portion 11 is axially clamped between the wear-resistant material annular support member 40 and the clamping member 50.

[0048] Space 12 radially separates the radially inner end of the root 11 from the annular support 40 of the wear-resistant material. In practice, the contact between the root 11 and the annular support 40 of the wear-resistant material is only axial. Space 12 remains above the entire periphery of the root 11 and the annular support 40 of the wear-resistant material.

[0049] Therefore, when the turbojet engine 100 is running, the root 11 can expand radially in the space 12 under the influence of temperature without applying stress to the annular support 40 of the wear-resistant material.

[0050] Furthermore, the root 11 can also be axially separated from the arm 42 of the wear-resistant annular support 40 and the body 52 of the clamping member 50.

[0051] like Figure 2 and Figure 3 As shown, the annular support 40 made of wear-resistant material may include axially oriented protrusions 43 for axially penetrating into a notch disposed in the root 11. For improved readability, Figure 3 The clamping component 50 is omitted. In this example, the notch extends over the entire axial width of the root 11 and is therefore a through notch. The protrusion 43 can contact the azimuth of the root 11 on either side of its azimuth end.

[0052] The annular support 40 of the wear-resistant material may include a plurality of protrusions 43 distributed along its entire azimuth dimension. Specifically, the annular support 40 of the wear-resistant material may include three protrusions 43 distributed at 120° intervals around the annular support 40 of the wear-resistant material, which allows for greatly improved alignment of the annular support 40 of the wear-resistant material with the root 11. In this configuration, the root 11 includes three recesses corresponding to the three protrusions 43.

[0053] Figure 4 Corresponding to Figure 3 The cross-sectional view at plane IV, which is a plane along both the radial and axial directions, intersects the annular support of the wear-resistant material at the level of protrusion 43 by 40. At the level of protrusion 43, there is also a space 12 that radially separates the annular support 40 of the wear-resistant material and the root 11. In other words, space 12 radially separates the radially inner end of the root 11 and the radially outer end of the protrusion 43.

[0054] The clamping component 50 and the wear-resistant annular support 40 are mounted around the root 11 via a contractile fit. However, in some configurations, the clamping component 50 may be welded or screwed onto the wear-resistant annular support 40.

[0055] In the case where the wear-resistant material annular support 40 and clamping member 50 are assembled around the root 11 by screwing, the wear-resistant material annular support 40 includes a threaded portion that is configured to allow the clamping member 50 to be screwed.

[0056] Although the invention has been described with reference to specific exemplary embodiments, it will be apparent that modifications and alterations can be made to these examples without departing from the overall scope of the invention as defined by the claims. Specifically, features of the different embodiments illustrated / mentioned can be combined in other embodiments. Therefore, the specification and drawings should be considered in an illustrative rather than restrictive sense.

[0057] It is equally evident that all features described by the reference method can be applied individually or in combination to the apparatus, and conversely, all features described by the reference device can be applied individually or in combination to the method.

Claims

1. A rotating component for a turbine, comprising: Rotor, the rotor comprising: At least two consecutive rotor stages (20a, 20b), each consecutive rotor stage having multiple blades, and An annular rotor guard (30) connects the two consecutive rotor stages (20a, 20b). Stator, the stator comprising: At least one stator stage (10), said stator stage being disposed between the two consecutive rotor stages (20a, 20b), comprising: Multiple blades (13), each blade including the root of the turbine stator blade (11). Annular clamping component (50), and A ring-shaped support component made of wear-resistant material (40). The root (11) extends radially and is axially clamped between the annular support (40) and the annular clamping member (50) of the wear-resistant material, and The space (12) radially separates the radially inner end of the root (11) from the annular support (40) of the wear-resistant material, and The root (11) includes a notch configured to be fitted by interlocking with a protrusion (43) disposed in an annular support (40) of the wear-resistant material.

2. The rotating assembly according to claim 1, characterized in that, The clamping component (50) is a ring different from the annular support (40) of the wear-resistant material.

3. The rotating assembly according to claim 1 or 2, characterized in that, The stator stage (10) includes multiple segments, each segment including at least one blade (13) extending from the root (11).

4. The rotating assembly according to claim 1, characterized in that, The wear-resistant material annular support (40) includes a wear-resistant portion (41) facing at least one wiper (31) carried by the rotor cover (30).

5. The rotating assembly according to claim 1, characterized in that, The wear-resistant material ring support (40) is made of ceramic matrix composite material.

6. The rotating assembly according to claim 1, characterized in that, The wear-resistant material annular support (40) includes three protrusions (43), which are distributed at 120° intervals on the wear-resistant material annular support (40).

7. The rotating assembly according to claim 1, characterized in that, The wear-resistant material annular support (40) includes a threaded portion, and the clamping member (50) is configured to be screwed onto the wear-resistant material annular support (40).

8. The rotating assembly according to claim 1, characterized in that, The clamping component (50) and the wear-resistant material ring support (40) are assembled around the root (11) by shrink fitting.

9. The rotating assembly according to claim 1, characterized in that, The clamping component (50) and the annular support (40) of the wear-resistant material are assembled by welding around the root (11).

10. A turbojet engine (100) comprising a rotating assembly according to any one of claims 1 to 9.

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