A preform for a turbine engine blade, comprising a main fiber preform obtained by three-dimensional weaving and comprising: a first longitudinal segment, suitable for forming a blade root; a second longitudinal segment, extending upwards from the first longitudinal segment and suitable for forming an airfoil portion; and a first transverse segment, extending transversely from the junction between the first and second longitudinal segments to a substantially linear distal edge and suitable for forming a first platform; the preform further including at least one attachment tab provided under the first transverse segment at its distal edge, suitable for forming an attachment portion of the platform.

A preform for a turbine engine blade, comprising a main fiber preform obtained by three-dimensional weaving and comprising: a first longitudinal segment, suitable for forming a blade root; a second longitudinal segment, extending upwards from the first longitudinal segment and suitable for forming an airfoil portion; and a first transverse segment, extending transversely from the junction between the first and second longitudinal segments to a substantially linear distal edge and suitable for forming a first platform; the preform further including at least one attachment tab provided under the first transverse segment at its distal edge, suitable for forming an attachment portion of the platform.

A seal support structure is provided for a circumferential seal. In one embodiment, the seal support structure includes an engine support structure, a seal support, and a shoulder joining the engine support and seal support. The shoulder offsets the engine support from the seal support, and the shoulder and the seal support structure are configured to dampen vibration for the circumferential seal. The seal support structure may employ one or more dampening elements or materials to interoperate with a seal support structure to dampen vibration to a seal system.

A seal support structure is provided for a circumferential seal. In one embodiment, the seal support structure includes an engine support structure, a seal support, and a shoulder joining the engine support and seal support. The shoulder offsets the engine support from the seal support, and the shoulder and the seal support structure are configured to dampen vibration for the circumferential seal. The seal support structure may employ one or more dampening elements or materials to interoperate with a seal support structure to dampen vibration to a seal system.

A rotary machine includes a rotary shaft that rotates around an axis, a plurality of rotor blades arranged on an outer peripheral side of the rotary shaft in a circumferential direction in which the rotor blade has a blade root, a platform, and a blade main body; and each damper member provided radially inward of the platform, in which the platform includes a first end surface that faces one side in the circumferential direction, and a second end surface that faces the other side in the circumferential direction so that the second end surface faces the first end surface of the adjacent other platform, and the damper member includes a first damper provided on the first end surface and having a first abutting surface, a second damper that has a second abutting surface slidably abutting the first abutting surface of the first damper and is abuttable on the second end surface, and an elastic member that bonds together the first damper and the second damper.

A method for producing a vibration-damping structure combination for damping vibrations for movable masses, having a first structure and a further structure, the further structure movable within a stop surface defined by a first structure surface of the first structure. The method includes a) providing the first structure, having the first structure surface and which defines a coating surface of a coating at least in some sections; b) coating the first structure surface of the first structure with the coating, the coating surface of the coating being applied such that a cavity is formed; c) filling the cavity with the filler; d) curing the filler until the further structure having a further structure surface is formed, which lies against the coating surface; and e) removing the coating, the further structure thus being movable relative to the first structure within the stop surface defined by the first structure surface.

A unit cell (26) for use in a damping system (24) includes: an impacting structure (34); a cavity (32) encapsulating the impacting structure (34), the cavity (32) including a first hemisphere (32A) and a second hemisphere (32B), the cavity (32) disposed within a substrate (28), the substrate (28) forming an outer casing of the cavity (32); and at least one fluid (36) disposed in each of the first and second hemispheres (32A, 32B) between the impacting structure (34) and the outer casing (28).

A unit cell (26) for use in a damping system (24) includes: an impacting structure (34); a cavity (32) encapsulating the impacting structure (34), the cavity (32) including a first hemisphere (32A) and a second hemisphere (32B), the cavity (32) disposed within a substrate (28), the substrate (28) forming an outer casing of the cavity (32); and at least one fluid (36) disposed in each of the first and second hemispheres (32A, 32B) between the impacting structure (34) and the outer casing (28).

Provided is a jig for a vibration test of a rotor blade, for use in the vibration test for evaluating high cycle fatigue characteristics of the rotor blade for an aircraft engine, and the jig is provided with a jig body holding a dovetail portion of a fan blade and fixed onto an excitation table of a shaker, and a hydraulic jack that applies a load in a blade span direction to the fan blade to fix the fan blade to the jig body. Consequently, in the vibration test for evaluating the high cycle fatigue characteristics of the rotor blade, a test simulating an actual operation state can be carried out, the rotor blade can be efficiently excited to reach a large deformation region, and high cycle fatigue failure can occur without any increase in test cost.

Provided is a jig for a vibration test of a rotor blade, for use in the vibration test for evaluating high cycle fatigue characteristics of the rotor blade for an aircraft engine, and the jig is provided with a jig body holding a dovetail portion of a fan blade and fixed onto an excitation table of a shaker, and a hydraulic jack that applies a load in a blade span direction to the fan blade to fix the fan blade to the jig body. Consequently, in the vibration test for evaluating the high cycle fatigue characteristics of the rotor blade, a test simulating an actual operation state can be carried out, the rotor blade can be efficiently excited to reach a large deformation region, and high cycle fatigue failure can occur without any increase in test cost.