Turbine rotor for a turbomachine
By introducing a serrated cut and optimizing the lip position in the turbine rotor lip design, the problems of uncontrolled leakage flow and rotor lock-up were solved, improving the efficiency and reliability of the turbine.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SAFRAN AIRCRAFT ENGINES SAS
- Filing Date
- 2022-01-18
- Publication Date
- 2026-05-12
AI Technical Summary
In existing turbines, the leakage flow caused by the lip design is unrestricted, and the difference in thermal expansion between the lip and the wearable material ring may cause rotor lock-up, affecting turbine efficiency and reliability.
A serrated cut is introduced into the lip design of the turbine rotor to form front and rear teeth. The front teeth are set on the suction surface of the platform, and the rear teeth are set on the pressure surface. The height and position of the cut edge of the lip are optimized to control the leakage flow density.
It effectively reduces leakage flow, lowers mixing losses, improves turbine efficiency and reliability, and avoids rotor lock-up.
Smart Images
Figure CN116783369B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application lies in the field of turbomachines, in particular in the field of turbomachines for aircraft.
[0002] More precisely, the application relates to a turborotor, to a turbine comprising such a turborotor, and to a turbomachine equipped with such a turbine.
[0003] Preferably, the turbine is a low-pressure turbine. BACKGROUND
[0004] A gas turbine for a twin-spool aircraft successively comprises, from upstream to downstream, a low-pressure compressor, a high-pressure compressor, a combustion chamber, a high-pressure turbine and a low-pressure turbine. In the remainder of the description and in the claims, upstream and downstream are defined with respect to the general direction of the flow of the gas inside the turbomachine and thus inside the turbine (from upstream to downstream).
[0005] The turbine comprises a number of successive stages, each stage comprising a rotor and a stator comprising nozzles provided with fixed blades. The turbine extends along a longitudinal axis corresponding to the axis of rotation of the rotor.
[0006] The rotor comprises a rotor disc which, at its periphery, bears a plurality of blades extending radially or substantially radially from the disc. The radial direction is the direction perpendicular to the axis of the turbine and intersecting the axis.
[0007] Each blade comprises a profiled aerofoil which, at its distal end, i.e. the end furthest from the axis of rotation, extends by a radial outer heel. This radial outer heel comprises a platform which delimits the outer surface of the flow path of the gas circulating between the aerofoils in the turbine, and also comprises an upstream lip and a downstream lip extending radially outwards from said platform and circumferentially from one lateral edge of the platform to the other.
[0008] During rotation of the rotor, the upstream lip and the downstream lip interact by rubbing against fixed abradable elements assembled opposite on the radial inner surface of the casing of the turbine to ensure sealing. These different abradable elements are assembled circumferentially end to end to form an abradable material ring.
[0009] Thus, a labyrinth-type seal is formed which makes it possible to limit the flow of air axially through the space located between the radial outer end of the stator and the rotor, more precisely between the abradable material ring and the radial outer end of the rotor.
[0010] The rotor / stator clearance plays a crucial role in the appropriate efficiency of low-pressure turbines. Limiting this clearance maximizes the flow of air in the rotor and reduces leakage flow. Sealing also minimizes the shear between leaking air flowing radially between the outer heel and the stator and the air flowing through the air path, which produces so-called "mixing" losses.
[0011] However, maintaining a small gap between the lip and the wearable material ring can lead to contact between the lip and the wearable material due to differential thermal expansion. This can even cause rotor lock-up in some cases.
[0012] In the prior art, lips with straight edges are known. In this invention, it is envisioned that a cut be made at the top of the lip, allowing the lip to penetrate the abrasive material with minimal cutting force, thereby avoiding rotor lock-up. However, the risk of using these cuts is that they create additional gaps between the rotor and stator, thus leading to irregular leakage flow.
[0013] Furthermore, the upstream and downstream portions of the platform can have various shapes and include notches, particularly to reduce the weight of the platform and limit the forces generated by centrifugal forces experienced by the platform. According to the invention, the aim is to further reduce weight where these designs are involved.
[0014] A turbine rotor extending about a longitudinal axis is also known from document US 2018 / 010467. The rotor includes a blade assembly supporting at least one blade at its outer periphery. The airfoil of the blade is provided with a heel at its radially outer end, the heel including a platform equipped with an upstream lip and a downstream lip.
[0015] The platform has a front lateral edge and a rear lateral edge relative to the normal rotational direction of the rotor about the longitudinal axis, and a suction surface portion extending from the front lateral edge to the suction surface of the airfoil.
[0016] However, these lips do not have a serrated shape, thus defining triangular or truncated rectangular teeth equipped with a front edge perpendicular to the platform and a radially outer end, the radially outer end being straight and sloping backward from the top of the front edge along the direction of the platform.
[0017] Therefore, the leakage flow at the top of the lip is unrestricted. Summary of the Invention
[0018] The purpose of this invention is to limit leakage flow at the top of the lip.
[0019] For this purpose, the present invention relates to a rotor of a turbine extending about a longitudinal axis, the rotor including at least one blade assembly supporting at least one blade at its outer periphery, each blade including an airfoil having a heel at its radially outer end, the heel including a platform having an upstream lip and a downstream lip extending radially outward from the platform, the platform having a front lateral edge and a rear lateral edge relative to the normal rotational direction of the rotor about the longitudinal axis, and a suction surface portion extending from the front lateral edge to a suction surface of the airfoil.
[0020] According to the present invention, the upstream lip and the downstream lip each include a serrated cut to form front teeth and rear teeth relative to the normal rotational direction of the rotor about the longitudinal axis; the front teeth and rear teeth of each lip have a triangular or truncated rectangular shape; the front teeth and rear teeth of each lip are adjacent; the front teeth of the lip have a front edge perpendicular to the platform and a radial outer edge, the radial outer edge being straight and inclined backward from the top of the front edge along the direction of the platform; the rear teeth of the lip have a cut edge perpendicular to the platform and a radial outer edge, the radial outer edge being straight and inclined backward from the top of the cut edge along the direction of the platform; the front teeth of each lip are disposed on the suction surface portion of the platform.
[0021] Due to these features of the invention, particularly the fact that the front and rear teeth are adjacent on each lip, and the front teeth are positioned on the suction side of the platform, the empty space between the radially outer edge of the front teeth and the cutting edge of the rear teeth becomes a location with low leakage flow density, since the pressure at the lip boundary is specified by the air flowing in the air path. The pressure on the suction side of the blade is less than the pressure on the pressure side.
[0022] Conversely, due to the aforementioned features of the present invention, the rear tooth is thus positioned at a location with high leakage flow density.
[0023] Therefore, reduce the leakage flow.
[0024] Other advantageous and non-limiting features, individually or in combination, employed according to the invention:
[0025] - The cutting edge of the posterior teeth of the downstream lip is set closer to the suction surface than the edge near the front lateral side;
[0026] - The cutting edge of the rear teeth of the upstream lip is set to align with the suction surface of the airfoil;
[0027] - The height of the cutting edge of the posterior tooth of the upstream lip is greater than the height of the anterior edge of the anterior tooth of the same upstream lip, and / or, the height of the cutting edge of the posterior tooth of the downstream lip is greater than the height of the anterior edge of the anterior tooth of the same downstream lip.
[0028] - The platform includes an upstream platform portion extending upstream from the upstream lip, the upstream platform portion having a truncated parallelepiped shape, the upstream lip defining one side of the truncated parallelepiped shape;
[0029] - The platform includes a downstream platform portion extending downstream from the downstream lip, the downstream platform portion having a truncated parallelepiped shape, the downstream lip defining one side of the truncated parallelepiped shape.
[0030] The invention also relates to a turbine extending about a longitudinal axis, the turbine including a housing having a wearable material ring on its radially inner surface. According to the invention, the turbine includes a rotor as described above, the rotor being configured such that the tops of the rear teeth of the upstream and downstream lips are positioned opposite the wearable material ring, such that for each upstream and downstream lip, the space defined by the wearable material ring, the cutting edges of the front and rear teeth is positioned perpendicular to the wearable material ring.
[0031] Finally, the present invention relates to a turbine, particularly for use in aircraft, comprising the turbine described above. Attached Figure Description
[0032] Other features, objects, and advantages of the invention will become apparent from the following description, which is purely illustrative and non-limiting and must be read with reference to the accompanying drawings, in which:
[0033] - Figure 1 A partial longitudinal axial sectional view of the radially outer portion of the low-pressure turbine of the turbine is shown;
[0034] - Figure 2 The illustration shows a possible embodiment of the blades of the turbine rotor according to the present invention in a perspective and partial manner;
[0035] - Figure 3 This is a diagram showing the radial outer heel portion of the blade according to the present invention;
[0036] - Figure 4 It is a schematic cross-sectional view of two adjacent blade sections and their corresponding upstream lips;
[0037] - Figure 5 It is a schematic cross-sectional view of two adjacent blade sections and their corresponding downstream lips. Detailed Implementation
[0038] Figure 1A portion of the low-pressure turbine is shown in a longitudinal sectional view (i.e., along the longitudinal axis X-X' of the low-pressure turbine). As described above, the turbine 1 comprises several consecutive stages. Each stage includes a rotor 2 and a stator, the rotor 2 being provided with blades 20, and the stator including nozzles 3 provided with fixed blades 30.
[0039] If possible Figure 2 As seen above, the rotor 2 includes a rotor disk 21 (blade assembly) (shown in dashed lines), which supports at least one blade 20 at its outer periphery, preferably supporting blades 20 that extend radially or substantially radially from the disk.
[0040] Rotor 2 is driven to rotate about its axis of rotation X-X', and along the normal direction of rotation (by... Figure 2 (Indicated by arrow F) is driven. The term "normal direction of rotation" should be understood as meaning the direction of rotor rotation during turbine operation. Furthermore, the different rotor disks 21 of the turbine are assembled together and driven to rotate about the longitudinal axis X-X'.
[0041] Each blade 20 includes a shaped airfoil 22 and a radially inner root 23, the radially inner root 23 having, for example, a dovetail shape or a similar shape, mounted in a correspondingly shaped recess 210 formed on the outer periphery of the rotor disk 21. The airfoil 22 is separated from the radially inner root 23 by a radially inner root 24. Finally, a radially outer root 25 extends from the radially outer end (or distal end) of the airfoil 22.
[0042] Each airfoil 22 has a suction surface 221 and a pressure surface 222, a front edge 223 and a rear edge 224.
[0043] When different blades 20 are attached to the rotor disk 21, the radially outer heels 25 of these blades 20 are arranged edge to edge to form a rotating circumferential ring that defines a rotating surface around the rotation axis X-X' of the disk.
[0044] More specifically, each radially outer heel portion 25 includes a platform 26, which defines the outer surface of the airflow path of the gas flowing through the turbine between the airfoils 22, and the platform 26 has opposing front lateral edges 260 and rear lateral edges 261. Edge 260 is referred to as the "front lateral edge," and edge 261 is referred to as the "rear lateral edge." In the remainder of the specification and claims, the terms "front" and "rear" are defined relative to the normal direction of rotation of the rotor. It should also be noted that the front lateral edge 260 is the edge located on the suction side of the airfoil 22, and the rear lateral edge 261 is the edge located on the pressure side of the airfoil 22.
[0045] In addition, each radially outer heel portion 25 also includes an upstream sealing lip 27 and a downstream sealing lip 28, which extend radially or substantially radially outward from the platform 26 and circumferentially from the front side edge 260 to the rear side edge 261 of the platform.
[0046] When different blades 20 are attached to the rotor disk 21, such as Figure 2 As shown, the radially outer platforms 26 of these blades 20 are arranged end to end, such that the rear lateral edge 261 of one platform contacts the front lateral edge 260 of the next platform. Subsequently, different upstream lips 27 (or different downstream lips 28) are also arranged edge to edge to form an upstream rotating ring (or downstream rotating ring) about the axis X-X'.
[0047] If it is possible Figure 1 As seen in the image, the upstream lip 27 and the downstream lip 28 are disposed opposite to the wearable material ring 4, which is attached opposite to the radial inner surface of the housing 10 of the turbine 1 to form a labyrinth-type seal.
[0048] exist Figure 2 In the exemplary embodiment shown, it can be seen that the front lateral edge 260 and the rear lateral edge 261 have a zigzag-shaped profile in the central region of the platform 26, that is, between the two lips 27 and 28. Other shapes are conceivable, as long as the front lateral edge 260 and the rear lateral edge 261 are complementary to each other and allow the above-described assembly.
[0049] Furthermore, platform 26 has a downstream platform portion 262 extending downstream from the downstream lip 28. Similarly, platform 26 has an upstream platform portion 263 extending upstream from the upstream lip 27.
[0050] Figure 2 The upstream and downstream lips of the blade located on the right side of the figure are intentionally avoided being shown as a whole to better observe the shape of the platform 26 and its upstream portion 263 and downstream portion 262. These lips are shown by dashed lines.
[0051] In addition, such as in Figure 2 As can be seen more clearly, platform 26 has a portion called a "suction surface portion" 264 and a portion called a "pressure surface portion" 265. The suction surface portion 264 extends from the front side to the edge 260 to the suction surface 221 of the airfoil 22, and the pressure surface portion 265 extends from the pressure surface 222 of the airfoil 22 to the rear side to the edge 261. Figure 2 In the diagram, the suction surface portion 264 is shown as a shaded area.
[0052] As in Figure 3As can be seen more clearly in one possible embodiment of the invention, the downstream platform portion 262 has a parallelepiped shape and thus includes a downstream edge 2620, a front lateral edge 2621, and a rear lateral edge 2622 located on the downstream side of the platform 26 (see dashed outline). Finally, the last side of the parallelepiped is defined by a downstream lip 28.
[0053] According to one possible embodiment of the invention, the upstream platform portion 263 also has a parallelepiped shape and includes an upstream edge 2630, a front lateral edge 2631, and a rear lateral edge 2632 located on the upstream side of the platform 26 (see dashed outline). Finally, the last side of the parallelepiped is defined by the upstream lip 27.
[0054] According to other possible embodiments of the invention, the parallelepipeds forming the upstream platform portion 263 and / or the parallelepipeds forming the downstream platform portion 262 are truncated and have one or more notches to reduce the weight of the platform 26.
[0055] In the exemplary embodiment shown in the figure, the two portions 263 and 262 are truncated, and an example of the notch is described below.
[0056] Therefore, preferably, the downstream platform portion 262 includes a notch 2623, which is formed at an angle between the downstream edge 2620 and the front lateral edge 2621.
[0057] Preferably, the notch 2623 has a straight edge. The profile may also have other shapes, such as a curved shape, preferably a concave curved shape.
[0058] Preferably, the notch 2623 extends from the front side toward the edge 2621, positioned near the downstream lip 28, to the downstream edge 2620, positioned perpendicular to the rear edge 224 of the airfoil 22.
[0059] Preferably, the upstream platform portion 263 includes two notches, namely a front notch 2633 and a rear notch 2634. The front notch 2633 is formed at a certain angle between the front lateral edge 2631 and the upstream edge 2630, and the rear notch 2634 is formed at a certain angle between the rear lateral edge 2632 and the upstream edge 2630.
[0060] Preferably, the two notches 2633 and 2634 have a curved and concave profile. Other shapes, such as straight shapes, are conceivable.
[0061] Preferably, the front notch 2633 extends from the front side toward the edge 2631, positioned near the upstream lip 27, to the upstream edge 2630, positioned perpendicular to the front edge 223 (on the suction side), to remove the maximum amount of material from the upstream platform portion while keeping the upstream portion radially above the airfoil 22.
[0062] Preferably, for the same reason, the rear notch 2634 is positioned from the rear side toward the edge 2632 at a point near the upstream lip 27 and extends to the upstream edge 2630 at a point perpendicular to the front edge 223 (located on the pressure side).
[0063] According to the present invention, such as can be Figure 4 and Figure 5 As can be seen more readily, the upstream lip 27 and the downstream lip 28 have serrated cuts to form two adjacent teeth, namely, for the upstream lip 27, the two adjacent teeth are front tooth 271 and rear tooth 272, and for the downstream lip 28, the two adjacent teeth are front tooth 281 and rear tooth 282, the front and rear being defined relative to the normal rotational direction of the rotor about the axis X-X' (arrow F).
[0064] As can be seen in these figures, the front teeth 271 and 281 each have front edges 2710 and 2810, and the rear teeth 272 and 282 each have cutting edges 2720 and 2820. The cutting edges 2720 and 2820 are also oriented forward relative to the direction of rotation and are configured to shear the wearable material ring 4 when in contact with it.
[0065] Preferably, the front teeth 271, 281 or the rear teeth 272, 282 have a triangular shape or a truncated rectangular shape.
[0066] In the exemplary embodiment shown in the figure, the front teeth 271, 281 are triangular, and the rear teeth 272, 282 have a truncated rectangular shape.
[0067] The front tooth 271 has a radial outer edge 2711 that slopes backward from the top of the front edge 2710 along the direction of the platform 26 to the base of the cutting edge 2720 of the rear tooth 272, while the front tooth 281 has a radial outer edge 2811 that slopes backward from the top of the front edge 2810 to the base of the cutting edge 2820 of the rear tooth 282.
[0068] The rear tooth 272 has a radially outer edge 2721, which slopes along the direction of the platform 26 from the top of the cutting edge 2720 to the rear edge 2722 of the rear tooth 272 (in Figure 2(See more clearly in the middle). Similarly, the rear tooth 282 has a radial outer edge 2821 that slopes along the direction of the platform 26 from the top of the cutting edge 2820 to the rear edge 2822 of the rear tooth 282.
[0069] Preferably, the front edges 2710, 2810 and the rear edges 2722, 2822 are perpendicular to or slightly inclined to the plane of the platform 26, such that when the two platforms 26 are placed end to end, the rear edge 2722 of the rear tooth 272 of the upstream lip 27 of one platform contacts the front edge 2710 of the front tooth 271 of the upstream lip 27 of the adjacent platform, ensuring the circumferential continuity of the upstream lip. The same principle applies to the downstream lip 28.
[0070] Preferably, the rear edge 2722 of the upstream lip 27 has the same height H2 as its front edge 2710, such that when the two blades 2 (and therefore the two platforms 26) are placed side by side, the rear edge of one blade is at the same level as the front edge of the other blade. Preferably, the same principle applies to the height H3 of the front edge 2810 and the rear edge 2822.
[0071] Preferably, the cutting edges 2720 and 2820 are perpendicular to the plane of the platform 26.
[0072] Preferably, the cutting edge 2720 of the rear tooth has a greater height than the front edge 2710 of the front tooth 271. For this reason, the cutting edge 2720 will shear the wearable material ring 4 (the height H1 between the top of the cutting edge 2720 and the platform 26 is greater than the height H2 between the top of the front edge 2710 and the platform 26). Similarly, preferably, the height H4 of the cutting edge 2820 of the rear tooth 282 is greater than the height H3 of the front edge 2810.
[0073] In the embodiment just described, the radial outer edges 2711, 2721, 2811, 2821 have a straight profile. However, at least one of these profiles may be slightly curved and convex.
[0074] According to the invention, cuts are formed in the upstream and downstream lips such that the front and rear teeth are positioned on the platform 26 at points that enable compensation for irregularities in leakage flow.
[0075] The air pressure flowing in the air path and thus between platform 26 and wearable material ring 4 is higher upstream than downstream, which allows air to flow in turbine 1. In addition, the pressure applied to pressure surface 222 is greater than the pressure applied to suction surface 221 of airfoil 22, causing rotor 2 to rotate.
[0076] Therefore, the pressure P exerted by the leaked air on the upstream lip 27 on the suction side上游吸力 Greater than the pressure P applied to the upstream lip 27 on the pressure surface side 上游压力 The pressure P 上游压力 It is greater than the pressure P exerted by the leaked air on the downstream lip 28 on the suction side. 下游吸力 The pressure P 下游吸力 It is greater than the pressure P exerted by the leaked air on the downstream lip 28 on the pressure side. 下游压力 The term "leaked air" should be understood to mean the air flowing between platform 26 and the wearable material ring 4.
[0077] In addition, Figure 4 and Figure 5 In the right half, the mixing line shows the level 40 where the wearable material ring 4 is located when the rotor 2 is assembled in the turbine 1.
[0078] A cut is formed on the upstream lip 27, so that the anterior teeth 271 are positioned on the suction surface portion 264 of the platform 26. Therefore, as can be Figure 4 As seen in the diagram, the space E1 defined by the cutting edges 2720 of the wearable material ring 4, the front tooth 271, and the rear tooth 272 is thus positioned perpendicular to the suction surface portion 264 of the platform 26, i.e., located at a lower leakage flow rate. Furthermore, since the height H2 of the front tooth 271 is preferably smaller than the height H1 of the rear tooth 272, the space E1 is larger overall.
[0079] Conversely, given the adjacency of the front tooth 271 and the rear tooth 272, the rear tooth 272 is thus positioned primarily on the pressure surface portion 265 of the platform 26, at a location with higher leakage flow, thereby limiting leakage. The reduced surface area of the space E2 extending between the rear tooth 272 and the wearable material ring 4 (horizontal 40) further limits the leakage flow at that location.
[0080] Preferably, the teeth are positioned such that the cutting edge 2720 of the rear tooth 272 is positioned closer to the suction surface 221 of the airfoil 22 than the front lateral edge 260; and preferably, the cutting edge 2720 of the rear tooth 272 is aligned with the suction surface 221 of the airfoil 22. Therefore, the space E1 above the suction surface portion 264 is maximized.
[0081] Compared with existing technologies, the total leakage portion (i.e., the sum of spaces E1 and E2) remains unchanged, but the leakage flow rate is reduced.
[0082] Similarly, a cut is formed on the downstream lip 28, so that the anterior teeth 281 are positioned on the suction surface portion 264 of the platform 26. Therefore, as can be Figure 5As seen in the image, the space E3 defined by the cutting edges 2820 of the wearable material ring 4, the front tooth 281, and the rear tooth 282 is thus positioned perpendicular to the suction surface portion 264 of the platform, i.e., at a location with lower leakage flow.
[0083] Preferably, the teeth are positioned such that the cutting edge 2820 of the rear tooth 282 is positioned closer to the suction surface 221 than the front lateral edge 260.
[0084] Compared with existing technologies, the total leakage portion (i.e., the sum of spaces E3 and E4) remains unchanged, but the leakage flow rate is reduced.
[0085] If platform 26 is not truncated, a reduction in leakage flow is observed, and this improvement is further enhanced if platform 26 has notches, such as the notches 2623, 2633 and 2634 mentioned above.
Claims
1. A rotor (2) of a turbine (1) extending about a longitudinal axis (X-X'), the rotor comprising at least one blade assembly supporting at least one blade (20) at its outer periphery, each blade (20) comprising an airfoil (22) having a heel (25) at its radially outer end, the heel (25) comprising a platform (26) having an upstream lip (27) and a downstream lip (28) extending radially outward from the platform (26), the platform (26) having a front lateral edge (260) and a rear lateral edge (261) relative to the normal rotational direction of the rotor (2) about the longitudinal axis (X-X'), and a suction surface portion (264) extending from the front lateral edge (260) to the suction surface of the airfoil (22), characterized in that, The upstream lip (27) and the downstream lip (28) each include a serrated cut to form front teeth (271, 281) and rear teeth (272, 282) relative to the normal rotational direction of the rotor (2) about the longitudinal axis (X-X'); the front teeth (271, 281) and rear teeth (272, 282) of each of the upstream lip (27) and the downstream lip (28) have a triangular or truncated rectangular shape; the front teeth (271, 281) and rear teeth (272, 282) of each of the upstream lip (27) and the downstream lip (28) are adjacent; the front teeth (271, 281) of each of the upstream lip (27) and the downstream lip (28) have a front edge (2710, 2810) perpendicular to the platform (26) and a radial outer edge (2711). , 2811), the radial outer edges (2711, 2811) of the front teeth are straight and slope backward from the top of the front edges (2710, 2810) along the direction of the platform (26); the rear teeth (272, 282) of each of the upstream lip (27) and the downstream lip (28) have cutting edges (2720, 2820) perpendicular to the platform (26) and radial outer edges (2721, 2821) as follows, the radial outer edges (2721, 2821) of the rear teeth are straight and slope backward from the top of the cutting edges (2720, 2820) along the direction of the platform (26); the front teeth (271, 281) of each of the upstream lip (27) and the downstream lip (28) are disposed on the suction surface portion (264) of the platform (26).
2. The rotor (2) according to claim 1, characterized in that, The cutting edge (2820) of the rear tooth (282) of the downstream lip (28) is set closer to the suction surface (221) of the airfoil (22) than the front lateral edge (260).
3. The rotor (2) according to claim 1 or 2, characterized in that, The cutting edge (2720) of the rear tooth (272) of the upstream lip (27) is configured to align with the suction surface (221) of the airfoil (22).
4. The rotor (2) according to claim 1 or 2, characterized in that, The height (H1) of the cutting edge (2720) of the posterior tooth (272) of the upstream lip (27) is greater than the height (H2) of the front edge (2710) of the anterior tooth (271) of the same upstream lip (27), and / or the height (H4) of the cutting edge (2820) of the posterior tooth (282) of the downstream lip (28) is greater than the height (H3) of the front edge (2810) of the anterior tooth (281) of the same downstream lip (28).
5. The rotor (2) according to claim 1 or 2, characterized in that, The platform (26) includes an upstream platform portion (263) extending upstream from the upstream lip (27), the upstream platform portion (263) having a truncated parallelepiped shape, the upstream lip (27) defining one side of the truncated parallelepiped shape.
6. The rotor (2) according to claim 1 or 2, characterized in that, The platform (26) includes a downstream platform portion (262) extending downstream from the downstream lip (28), the downstream platform portion (262) having a truncated parallelepiped shape, the downstream lip (28) defining one side of the truncated parallelepiped shape.
7. A turbine (1) extending about a longitudinal axis (X-X'), comprising a housing (10) having a wearable material ring (4) on its radially inner surface, characterized in that, The turbine includes a rotor (2) according to any one of claims 1 to 6; the rotor (2) is configured such that the tops of the rear teeth (272, 282) of the upstream lip (27) and the downstream lip (28) are positioned opposite to the wearable material ring (4), such that for each upstream lip (27) and each downstream lip (28), the space (E1, E3) defined by the wearable material ring (4), the cutting edges (2720, 2820) of the front teeth (271, 281) and the rear teeth (272, 282) is positioned perpendicular to the wearable material ring (4).
8. A turbine, characterized in that, The turbine includes the turbine (1) according to claim 7.
9. The turbine according to claim 8, characterized in that, The turbine in question is a turbine used in aircraft.