Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
  • F01D5/12—Blades
  • F01D5/22—Blade-to-blade connections, e.g. for damping vibrations
  • F01D5/225—Blade-to-blade connections, e.g. for damping vibrations by shrouding
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2220/00—Application
  • F05D2220/30—Application in turbines
  • F05D2220/32—Application in turbines in gas turbines
  • F05D2220/323—Application in turbines in gas turbines for aircraft propulsion, e.g. jet engines
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2240/00—Components
  • F05D2240/80—Platforms for stationary or moving blades
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2260/00—Function
  • F05D2260/96—Preventing, counteracting or reducing vibration or noise
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
  • F05D2300/00—Materials; Properties thereof
  • F05D2300/60—Properties or characteristics given to material by treatment or manufacturing
  • F05D2300/603—Composites; e.g. fibre-reinforced
  • F05D2300/6033—Ceramic matrix composites [CMC]

Definitions

• Bladed turbomachine assembly comprising means of limiting vibrations between platforms
• the invention relates to a bladed turbomachine assembly designed to provide vibration damping of the outer radial ends of moving blades by cooperation with each other.
• the invention aims to replace existing solutions consisting of assembling the blades with pre-tensioning during assembly.
• the blades and more particularly the moving blades, are subject to various vibrations.
• This assembly involves particular shapes of the blade platforms, to fit together in a predefined manner.
• the contact force between the platforms can vary, which can harm to vibration damping.
• the aim of the invention is to propose a bladed turbomachine assembly which is designed to allow damping of vibrations by friction without having to prestress the blades during assembly.
• the invention proposes a bladed turbomachine assembly extending around a main axis A and comprising at least two circumferentially adjacent blades, each blade comprising a blade extending in a direction of radial extension relative to said main axis A and a platform located at a free radial end of the blade, in which the platform of each blade of the bladed assembly is located circumferentially opposite a platform of the other circumferentially adjacent blade of the bladed assembly, in which the bladed assembly comprises an insert arranged circumferentially between the platforms and which cooperates with the platforms, characterized in that each platform comprises a circumferential bearing face against which a circumferential end of the insert is in contact, and in this that the direction of contact between each circumferential bearing face and the insert is oriented circumferentially relative to the main axis A.
• At least one of the two platforms comprises a groove open circumferentially towards the other of the two platforms, one face of the groove forms the circumferential support face and in which said groove, a circumferential end of the insert is received.
• said circumferential bearing face is in the shape of an arc of a circle or is inclined relative to the radial direction.
• the circumferential support face of a platform is parallel to a radial direction relative to the main axis A.
• the circumferential bearing face has a groove.
• the insert has two contact faces, each contact face of which has a shape complementary to the shape of the support face associated with it.
• At least one contact face of the insert is in the shape of a cylinder arc whose axis is parallel to the main direction of the insert.
• each circumferential end of the insert is received with radial play and circumferential play in the groove associated with it.
• each platform has a boss of radial thickness greater than the thickness of the rest of the platform, in which said boss the groove is formed.
• the bladed assembly comprises means for axial retention of the insert between the two platforms.
• the axial retention means comprise at least one finger carried by the insert which extends circumferentially projecting from the insert and which is received in an associated notch formed hollow circumferentially in at least one of the platforms.
• the invention also proposes an aircraft turbomachine comprising a bladed assembly according to the invention.
• FIG. 1 is an end view of a bladed turbomachine assembly in a radial direction relative to a main axis of the bladed assembly.
• FIG. 2 is a section of the bladed assembly shown in Figure 1 along a plane perpendicular to the main axis of the bladed assembly.
• FIG. 3 is a view similar to that of Figure 2, showing another relative position of the insert relative to the platforms in the event of expansion of the latter.
• FIG. 4 is a view similar to that of Figure 1, showing an alternative embodiment of the insert.
• FIG. 5 is a view similar to that of Figure 2, showing a section of the bladed assembly shown in Figure 4.
• FIG. 6 is a section of a bladed assembly taken in a circumferential direction, showing a first embodiment of means for retaining the insert.
• FIG. 7 is a section similar to that of Figure 6, showing another embodiment of the retaining means.
• FIG. 8 is a partial view of a turbomachine rotor element equipped with a bladed assembly according to the invention.
• the figures show a part of a bladed assembly 10 of a turbomachine comprising two circumferentially adjacent blades 12.
• the turbomachine comprising the bladed assembly 10 is an aircraft turbomachine.
• This bladed assembly 10 is preferably a component belonging to a rotor disk of the turbomachine such as the rotor disk DR, part of which is shown in Figure 8.
• the blades 12 can then be mounted by their feet in corresponding cells of this disk DR by constituting a crown of blades 21a, 21b which surround the disk DR while being carried by it.
• the blades 12 are moving blades of a low pressure turbine of a turbomachine. It will be understood that the invention is not limited to this embodiment and that it may also relate to moving blades of other modules of the turbomachine or fixed blades.
• the bladed assembly 10 has a main axis A which is intended to coincide with, or coaxial with, the main axis of the turbomachine when the bladed assembly 10 is mounted therein.
• Each blade 12 comprises a blade 14 extending in a radial direction relative to the main axis, a first radial end part 15 called the root which is connected to a first radial end of the blade 14 and a second part of the radial end 16 called platform, which is connected to a second radial end of the blade 14.
• the platform 16 is connected to the free radial end of the blade 14, that is to say the radial end of the blade 14 which is not fixed to a rotating element supporting the blades 12.
• the platform 16 is located at the outer radial end of the blade 14.
• the inner radial end of the blade 14 carries the root 15 of the blade 12, by which the blade is mounted on the support element.
• the foot 15 of the blade 12 is mounted in a cell 17 of the disk of the rotor DR of the turbomachine.
• the outer radial end of the blade 12, which is opposite the foot 15 for fixing the blade 12 to the rotor, further comprises sealing lips (not shown).
• the bladed assembly 10 shown in the figures consists of two blades 12 which are circumferentially adjacent in the turbomachine.
• the platforms 16 of the blades 12 are located close to each other in a circumferential direction.
• Each platform 16 has a side face 18 which is located circumferentially opposite and at a distance from a side face 18 of the platform 16 of the circumferentially adjacent blade.
• the two lateral faces 18 facing each other are parallel to each other and are inclined relative to a plane passing through the main axis of the bladed assembly 10.
• the bladed assembly 10 also comprises an insert 20 which is arranged circumferentially between the platforms of the two circumferentially adjacent blades 12 and which cooperates with the two platforms 16 simultaneously, so that when vibrations are produced on the blades 12, friction occurs between the insert 20 and the platforms 16 to reduce the amplitude of the vibratory movements of the platforms 16.
• the insert 20 cooperates with the platforms 16 to reduce vibrations.
• each side face 18 of one of the two platforms 16 has a support face 32 against which the insert 20 rests.
• the support of the insert 20 on the support face 32 is oriented at least partly circumferentially relative to the main axis A.
• At least one bearing face 32 against which the insert 20 bears is inclined relative to the radial direction.
• the side face 18 of at least one platform 16 includes a groove 22 receiving a circumferential end of the insert 20 associated with it.
• This groove 22 has a face forming the support face 32 of the platform and it opens in the circumferential direction towards the platform 16 of the other blade 12.
• the bearing face 32 is the radially external face of the groove 22, which is oriented partly radially inwards, that is to say towards the main axis A, and partly circumferentially towards the other platform 16.
• the support face 32 of one of the two platforms 16, here the platform 16 on the right extends in a plane parallel to the radial direction.
• the support of the insert 20 against this support face 32 is oriented entirely circumferentially relative to the main axis A.
• only the support face 32 of the other platform 16, that is to say here the platform 16 on the left, has a groove 22 comprising a support face 32.
• the insert 20 is both compressed circumferentially between the two supporting faces 32 of the two platforms 16 and it bears radially outwards against the supporting face 32 of the platform on the left, partly delimiting the groove 22.
• the support of the insert 20 against the inclined support face 32 causes a support of the insert 20 against the other support face 32, which is oriented radially, in the circumferential direction.
• the inclination of a support face also makes it possible to compensate for the dimensional variations of the blades 12 caused by their expansion.
• the circumferentially adjacent platforms 16 are caused to deviate circumferentially from each other. Since at least one support face 32 is inclined relative to the radial direction, even if the platforms 16 deviate circumferentially from each other, that is to say that the support faces 32 deviate circumferentially from each other, the insert 20 moves radially relative to the main axis A, while remaining in contact with the two supporting faces 32.
• each platform 16 has a groove 22 receiving a circumferential end of the insert 20 which is associated with it.
• This groove 22 has a face forming the support face 32 of the platform and it opens in the circumferential direction towards the platform 16 of the other blade 12.
• the bearing face 32 is the radially external face of the groove 22, which is oriented partly radially inwards, that is to say towards the main axis A, and partly circumferentially towards the other platform 16.
• the insert 20 comprises contact faces 34 which are intended to come into contact with the support faces 32 of the platforms 16.
• Each contact face 34 has a shape complementary to the shape of the support face 32 which is attached to it. associated.
• the contact face 34 and the support face 32 associated with it being arranged circumferentially facing each other.
• a contact face 34 is partly oriented radially outwards, that is to say which moves away from the main axis A, and partly circumferentially in the direction of the platform 16 associated with the contact face 34.
• the other contact face 34 extends in a plane parallel to the radial direction so that the support of the insert 20 against the support face 32 associated is oriented entirely circumferentially relative to the main axis A.
• each of the two contact faces 34 is partly oriented radially outwards, that is to say which moves away from the main axis A, and partly circumferentially towards the platform 16 associated with the contact face 34.
• the insert 20 in order to allow relative movement of the platforms 16 relative to each other, in particular due to the expansion of the blades 12, the insert 20 is received with clearance in the groove 22 or the two grooves 22.
• each circumferential end of the insert 20 is received with a radial clearance and a circumferential clearance in each of the two grooves 22
• each groove 22 the radial dimension as well as the depth, measured circumferentially, of each groove 22 is greater than the radial thickness of the insert 20 and the circumferential length of the part of the insert which is received in each groove 22.
• the contact face 34 of the insert 20 is curved radially outwards.
• the contact face 34 of the insert 20 is in the shape of a cylinder arc whose axis is parallel to the substantially axial main direction of the insert 20.
• the bearing face 32 of each groove 22 is also convex and forms a cylinder arc whose axis is parallel to the substantially axial main direction of the lateral face 18.
• the radius of the cylinder associated with each bearing face 32 of a groove 22 is greater than the radius of the cylinder associated with the contact face 34 of the insert 20.
• a platform 16 To receive each groove 22, a platform 16 has a boss 28, that is to say a radial extra thickness. This extra thickness results in an increase in the mass of the platform 16. Thus, the greater the length of the insert 20, or the associated grooves 22, the greater the mass of the platform 16.
• the bladed assembly 10 comprises means for axial retention of the insert 20 between the two platforms 16.
• the axial length of the insert 20 and the groove 22 associated with it is less than the axial length of the platform 16 and the groove 22 does not open into each axial end of the platform 16.
• the insert 20 is able to abut axially against an axial end of the groove 22 in which it is partly received.
• these axial retention means consist of fingers 36 which project circumferentially relative to the rest of the insert 20 and which are received in associated notches 38 formed in the platforms 16.
• the fingers 36 and notches 38 are designed to allow relative movement of the insert 20 relative to the platforms 16 in the radial direction.
• the platform 16 and the functional surfaces thereof, that is to say the boss 28, the side face 18 and the walls of the groove 22 are made of CMC, that is to say say in Ceramic Matrix Composite, by weaving, molding then possibly machining the functional parts.
• the insert 20 is for example made of a refractory metallic material based on nickel or cobalt or else in a monolithic or fiber reinforced ceramic material. It will be understood that the material constituting the insert is not limited to these examples and that other materials can be used so as to adapt to the chosen application, in terms of resistance to temperature and reduction of mass while respecting the maintenance of the insert 20 and generate the desired level of damping.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)
• Turbine Rotor Nozzle Sealing (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=83355737

Family Applications (1)

Country Status (5)

Family Cites Families (12)

• 2022
  • 2022-06-22 FR FR2206148A patent/FR3137127B1/fr active Active
• 2023
  • 2023-06-12 WO PCT/FR2023/050847 patent/WO2023247856A1/fr not_active Ceased
  • 2023-06-12 CN CN202380045431.7A patent/CN119452151A/zh active Pending
  • 2023-06-12 EP EP23736430.2A patent/EP4544153A1/de active Pending
  • 2023-06-12 US US18/869,432 patent/US12595743B2/en active Active

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