Abstract: A turbomachine casing forming a continuous annular ring extending over 360° around a bladed wheel and serving as a propagation medium for rotating waves, each rotating wave being generated by two standing waves of the same frequency, and the casing including at least one longitudinal stiffener at its outer periphery that is dimensioned and positioned in such a manner as to separate the frequencies of the two standing waves of at least one given rotating wave.

Abstract: An impeller including a blade, a support of the blade which extends substantially radially, at least one intermediate part extending, in a substantially axial direction, between the blade and the support of the blade, and at least one damping device placed on at least one face of the intermediate part is disclosed. The damping device is segmented in an axial and/or circumferential direction into at least two elementary damping devices.

Abstract: A lever for rotating about its pivot a turbomachine variable-pitch stator vane: including a first zone for attachment to a lever drive member, a second zone for attachment to the variable-pitch stator vane, and a third zone of elongate shape between the first zone and the second zone is disclosed. A vibration-damping laminate is applied to at least one surface portion of at least one of the zones of the lever. The laminate includes at least one layer of viscoelastic material in contact with the surface portion and a backing layer of rigid material.

Abstract: A cylindrical casing for a turbomachine that is suitable for receiving a rotor fitted with at least one bladed wheel is disclosed. The casing includes a device for preventing instability during contact between the casing and the bladed wheel. The device includes a succession of elements disposed around the circumference of the casing, and presenting different stiffnesses between two adjacent elements. The number of elements having the same stiffness not being equal to a multiple of the wave number of the vibratory mode of the bladed wheel that is to be inhibited. The invention is applicable to a compressor, a turbine, or a fan.

Abstract: A turbomachine stator forming a stator vane ring or upstream guide vane element including a plurality of vanes placed radially between a first inner ring and a second outer ring is disclosed. The two rings are concentric and the second ring has a cylindrical outer surface portion. The stator is characterized in that, on the outer surface portion, at least one vibration-damping laminate is attached. The laminate includes at least one layer of viscoelastic material in contact with the surface portion and one counterlayer of rigid material.

Abstract: The invention relates to a turbomachine thermomechanical part forming a body of revolution about a longitudinal axis, and including at least one abradable ring for a labyrinth seal. In characteristic manner, the abradable ring is made up of angular sectors that present different stiffnesses between adjacent pairs of sectors. The invention is applicable to a compressor, a turbine, or to a rotor and stator assembly.

Abstract: A hollow shaft of a turbomachine including a cylindrical wall with an inner surface portion and at one end a member for attachment to a rotor disk of the turbomachine is disclosed. The shaft also includes a damping device wherein at least one vibration-damping laminate is attached to the inner surface portion. The laminate includes at least one layer of viscoelastic material in contact with the surface portion and a counterlayer of rigid material.

Abstract: A turbomachine casing forming a continuous annular ring extending over 360° around a bladed wheel and serving as a propagation medium for rotating waves, each rotating wave being generated by two standing waves of the same frequency, and the casing including at least one longitudinal stiffener at its outer periphery that is dimensioned and positioned in such a manner as to separate the frequencies of the two standing waves of at least one given rotating wave.

Abstract: The invention relates to a turbomachine thermomechanical part forming a body of revolution about a longitudinal axis, and including at least one abradable ring for a labyrinth seal. In characteristic manner, the abradable ring is made up of angular sectors that present different stiffnesses between adjacent pairs of sectors. The invention is applicable to a compressor, a turbine, or to a rotor and stator assembly.

Abstract: A sector of a compressor guide vanes assembly or a sector of a turbomachine nozzle assembly. It comprises an inner ring sector (4), an outer ring sector (6) and a multitude of blades (8) connecting the inner ring sector (4) to the outer ring sector (6). The outer ring sector (6) or the inner ring sector (4) comprises radial cuts (10) situated between two consecutive blades (8) in such a way as to split them into the same number of elementary sectors as there are blades. Housings (14) are provided, secant to the radial cuts (10), damping inserts (16) being positioned in said housings.

Abstract: The invention relates to a cylindrical casing for a turbomachine that is suitable for receiving a rotor fitted with at least one bladed wheel, the casing including a device for preventing instability during contact between the casing and the bladed wheel. In characteristic manner, said device comprises a succession of elements disposed around the circumference of the casing, and presenting between two adjacent elements, different stiffnesses, the number of elements having the same stiffness not being equal to a multiple of the wave number of the vibratory mode of the bladed wheel that is to be inhibited. The invention is applicable to a compressor, a turbine, or a fan.

Abstract: The present invention relates to a lever for rotating about its pivot a turbomachine variable-pitch stator vane comprising three zones: a first zone for attachment to a lever drive member, a second zone for attachment to said variable-pitch stator vane, and a third zone of elongate shape between the first zone and the second zone, wherein a vibration-damping laminate is applied to at least one surface portion of at least one of said zones of the lever, the laminate comprising at least one layer of viscoelastic material in contact with said surface portion and a backing layer of rigid material.

Abstract: The present invention relates to a hollow shaft of a turbomachine comprising a cylindrical wall with an inner surface portion and at one end a member for attachment to a rotor disk of the turbomachine. The shaft also comprises a damping device wherein at least one vibration-damping laminate is attached to said inner surface portion, the laminate comprising at least one layer of viscoelastic material in contact with said surface portion and a counterlayer of rigid material.

Abstract: The impeller comprises a blade and a support of said blade which extend substantially radially. It also comprises at least one intermediate part extending, in a substantially axial direction, between said blade and said support of the blade, and at least one damping means placed on at least one face of said intermediate part. The damping means is segmented in an axial and/or circumferential direction into at least two elementary damping means.

Abstract: The present invention relates to a turbomachine stator forming a stator vane ring or upstream guide vane element comprising a plurality of vanes placed radially between a first inner ring and a second outer ring, the two rings being concentric, the second ring having a cylindrical outer surface portion. The stator is characterized in that, on said outer surface portion, at least one vibration-damping laminate is attached, the laminate comprising at least one layer of viscoelastic material in contact with said surface portion and one counterlayer of rigid material.

Abstract: A sector of a compressor guide vanes assembly or a sector of a turbomachine nozzle assembly. It comprises an inner ring sector (4), an outer ring sector (6) and a multitude of blades (8) connecting the inner ring sector (4) to the outer ring sector (6). The outer ring sector (6) or the inner ring sector (4) comprises radial cuts (10) situated between two consecutive blades (8) in such a way as to split them into the same number of elementary sectors as there are blades. Housings (14) are provided, secant to the radial cuts (10), damping inserts (16) being positioned in said housings.