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
  • F01D5/14—Form or construction
  • F01D5/16—Form or construction for counteracting blade vibration
• • 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
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T50/00—Aeronautics or air transport
  • Y02T50/60—Efficient propulsion technologies, e.g. for aircraft

Definitions

• This presentation concerns the field of bladed elements, and finds in particular a particular application for bladed wheels, in particular within the framework of a turbomachine rotor.
• Bladed wheels are indeed elements subject to vibration phenomena that can have a significant impact on the operation of a system.
• the asynchronous phenomena correspond to a purely aerodynamic excitation: the frequency is independent of the speed of rotation.
• the latter can be particularly destructive for blades if it is self-induced, for example in the case of flutter.
• the present presentation thus aims to respond at least partially to these problems.
• a turbomachine rotor comprising a body extending around a central axis, the body having an outer surface from which extend a plurality of blades, each of said blades having a blade root and a blade tip, defining an inner radial end and an outer radial end of the blade with respect to the central axis, said blades having the same blade height measured radially with respect to the axis central, characterized in that each of the blades is connected to the body by its blade root via a connection having a non-zero connection height, so that for all of said blades, the connection height of two successive blades is distinct .
• connection has a connection height of between 2% and 13% of the blade height.
• the difference between the connection heights of the connections of two successive blades is between 1% and 5% of the blade height.
• the difference between the connection heights of the connections of two successive blades is between 2% and 3% of the blade height
• the height of connection of the blades to the body varies according to a sinusoidal profile.
• the height of connection of the blades to the body varies according to a triangular profile.
• the body is an annular body having a central recess. [0015]according to one example, for each blade, the connection between the body and the blade root is made with a rounding having a section of a portion of a circle.
• connection between the body and the blade root is made so as to have a variable radius of curvature.
• the body and the blades form a one-piece bladed disc.
• This presentation also relates to a turbomachine comprising a turbomachine rotor as defined previously.
• Figure 1 is a view of a one-piece blisk according to an example application of the invention.
• Figure 2 is another view of a one-piece blisk according to an example application of the invention.
• FIG. 3 is a graph representing an example of evolution of the minimum radius of curvature of an assembly according to one aspect of the invention.
• FIG. 4 is a graph representing another example of evolution of the minimum radius of curvature of an assembly according to one aspect of the invention.
• Figure 5 schematically shows the definition of the connection height.
• Figures 1 and 2 are two views of an assembly 1 according to one aspect of the invention, which is shown here in the form of a one-piece bladed disc 1.
• the one-piece bladed disc 1 as shown is an example of application of the invention, in particular in the context of a turbomachine rotor. As will be understood on reading the description, the invention can be applied more generally to a component comprising a body having a plurality of blades, and being subjected to vibratory phenomena.
• the one-piece bladed disc 1 comprises 10 and a plurality of blades 20.
• the vanes 20 extend radially relative to the central axis X-X, from the outer face 14 of the body 10.
• connection between the blades 20 and the body 10 has a connection 30, so as to avoid sharp angles which generate stress concentrations.
• connection height corresponds to the distance measured in the radial direction, between the external radial end of the connection and its projection in the radial direction onto the internal vein.
• FIG. 5 schematizes an example of definition of connection height H with respect to a connection 30 and its projection 30P.
• connection height corresponding to the connection 30 considered changes according to the angular position of the associated blade 20 with respect to the central axis XX.
• the connection height corresponds to the height of the connection 30 considered measured in the radial direction with respect to the central axis XX. More specifically, the connection height of the connections 30 linking the roots of the blades 20 is not constant over the entire periphery of the body 10.
• this variation of the connection height is achieved by varying the minimum radius of curvature of the connections 30 linking the roots of the blades 20.
• connections 30 form roundings having a section of a portion of a circle, the minimum radius of curvature is then equal to the radius of the rounding, and the connection height is then typically equal to the radius of the round.
• Figures 3 and 4 illustrate two examples of evolution of the connection height via the evolution of the minimum radius of curvature for the different blades 20, the value of the minimum radius of curvature here being measured with respect to the height H of the blades 20, that is to say the maximum distance between the blade root 22 and the blade tip 24 for a given blade 20, the blades 20 typically having an identical height.
• connection height for the various blades 20 form patterns indicated in FIGS. 3 and 4 which are referred to as detuning patterns.
• connections 30 form a sinusoidal pattern.
• the connections 30 form a triangle pattern. It will be understood that the patterns are adapted in particular according to the number of blades 20 and the number of distinct values which are retained for the detuning pattern considered. It is also understood that these examples of patterns are not limiting.
• connection heights or typically the minimum radii of curvature for the various connections 30 typically have a value of between 2% and 13% of the height H, or even between 5% and 13% of height H.
• minimum connection height values or, where appropriate, minimum radius of curvature, are defined for each connection pattern.
• the present presentation thus makes it possible to achieve detuning by modifying the geometry of the connections 30 between the blades 20 and the body 10.
• the variation of the connection heights or, where appropriate, of the radii of curvature minimums of the various connections 30 as proposed makes it possible to have a frequency difference between the adjacent blades that is sufficiently constant to ensure asynchronous vibrational stability while gaining in robustness for the synchronous responses.
• the invention as proposed can for example be applied to a turbomachine component such as a one-piece bladed disc, or more generally to any component comprising a body having a plurality of blades, and being subjected to phenomena vibratory.

Landscapes

• 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)

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ID=74860303

Family Applications (1)

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Family Cites Families (4)

• 2021
  • 2021-02-10 FR FR2101263A patent/FR3119642B1/fr active Active
• 2022
  • 2022-02-01 EP EP22705447.5A patent/EP4291755A1/de active Pending
  • 2022-02-01 US US18/264,343 patent/US20240035385A1/en active Pending
  • 2022-02-01 WO PCT/FR2022/050188 patent/WO2022171946A1/fr active Application Filing
  • 2022-02-01 CN CN202280014222.1A patent/CN116848314A/zh active Pending

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