Abstract: A method includes: obtaining a rotor having a hub and a plurality of blades protruding from the hub, the plurality of blades including first blades and second blades disposed in alternation around a central axis of the rotor, natural vibration frequencies of the first blades different from natural vibration frequencies of the second blades; determining that a difference between a first natural vibration frequency of a first blade of the first blades and a second natural vibration frequency of a second blade of the second blades is below a threshold; and modifying a shape of the first blade until the difference between the first natural vibration frequency and the second natural vibration frequency is at or above the threshold.

Abstract: The present invention relates to a method of manufacturing a wind turbine blade (10). The method comprises arranging one or more shear webs (50, 55, 70) within a first shell half, adhesively joining the one or more shear webs to the first shell half, and adhesively joining the second shell half to the first shell half and to the one or more shear webs. The step of arranging the one or more shear webs within the first shell half comprises arranging at least one telescopic support member (80) between the inside surface (38b) of the first shell half (38) and the lateral surface (62) of at least one of the shear webs (70), wherein the telescopic support member (80) comprises an actuator (82) for adjusting the length of the telescopic support member.

Abstract: An integrally bladed disk is provided that includes a disk and a plurality of rotor blades. The disk has an outer radial hub and is configured for rotation around a rotational axis. Each rotor blade of the plurality of rotor blades has an airfoil that extends chordwise between a leading edge and a trailing edge, and extends spanwise between a base end and a blade tip. Each rotor blade includes a damper pocket, a damper body, and a plug. The damper pocket extends into the airfoil from the base end and has a first tapered configuration. The damper body is disposed within the damper pocket, and has a second tapered configuration. The second tapered configuration of the damper body mates with the first tapered configuration of the damper pocket. The plug is disposed to retain the damper body within the damper pocket.

Abstract: An apparatus is provided for a gas turbine engine. This apparatus includes a bladed rotor rotatable about an axis. The bladed rotor includes a rotor disk and a plurality of rotor blades projecting radially out from the rotor disk. The rotor blades are arranged circumferentially around the rotor disk in an array. The array of the rotor blades are divided into a plurality of sectors including a first sector and a second sector. The rotor blades are disposed in the first sector including a plurality of first rotor blades. Each of the first rotor blades includes a first coating. The rotor blades are disposed in the second sector including a plurality of second rotor blades. Each of the second rotor blades includes a second coating that is different from the first coating.

Abstract: A gas turbine engine includes a ceramic matrix composite (CMC) vane arc segments that are arranged in a circumferential row. Each of the CMC vane arc segments includes an airfoil section that defines first and second side walls, leading and trailing ends, and first and second radial ends. At the first radial end, the airfoil section has a single-sided platform that and the second side wall has a bearing surface. The single-sided platform of each of the CMC vane arc segments in the circumferential row is situated to bear against the bearing surface of the next of the CMC vane arc segments in the circumferential row.

Abstract: A shear web for a wind turbine blade includes a lower flange, an upper flange and a web structure extending between the lower and upper flanges, wherein at least one of the lower flange, upper flange, and the web structure includes an open lattice structure having a plurality of elongate fibrous composite spindles intersecting each other at multiple nodes of the structure. A method of making the shear web using a continuous fiber-reinforced additive manufacturing method is also disclosed.

Abstract: A blower includes a propeller fan, and an enclosure. The propeller fan is configured to rotate around a rotation axis. The propeller fan includes a plurality of blades at unequal pitches. The enclosure houses the propeller fan. The enclosure includes a bell mouth. The enclosure has a depth L. The bell mouth includes a cylindrical part parallel to the rotation axis. 0.14 ? H ? ? 2 H ? ? 0 ? 0.22 ? # A length of the blades is H0 in a rotation axis direction, and a length of the cylindrical part is H2 in the rotation axis direction.

Abstract: A tunable mass damper assembly is attachable to a rotor blade. The tunable mass damper assembly comprises a base configured to be attached to the rotor blade and a pendulum mass structure movably attached to the base and configured to move relative to the base in accordance with a rotational speed of the rotor blade about a rotor axis. The pendulum mass structure is configured to reduce vibratory forces of the rotor blade induced by a rotation of the rotor blade about the rotor axis. An entirety of the pendulum mass structure being configured to be contained within and enclosed by the rotor blade.

Abstract: A control surface system is disclosed having at least one body provided on an air vehicle; at least one wing flap for controlling air flow by moving relative to the body located thereon and thus allowing the air vehicle to maneuver; at least one actuator made of an electro-active polymer material located between the body and the wing flap, wherein the actuator changes shape depending on electrical energy and thus triggering the wing flap; at least one holder located on the actuator and attached to the actuator from at least a part; at least one housing on which the holder is removably attached and which can moves together with the holder by way of the action of the actuator.

Abstract: A wind turbine blade includes a profiled contour with a leading edge and a trailing edge, and a chord extending between the leading edge and the trailing edge, along with a blade shell with a pressure side and a suction side, a first main spar cap integrated in the pressure side of the blade shell, a second main spar cap integrated in the suction side of the blade shell, and one or more shear webs connected between the first main spar cap and the second main spar cap. The blade shell includes at least a first load carrying structure arranged at the leading edge or the trailing edge and having a first extension, including a first primary extension on a first side of the chord, where the first primary extension is at least 60% of the first extension.

Abstract: A composite airfoil having a non-metallic leading edge protective wrap is provided. In one aspect, the airfoil has a composite core having a pressure sidewall and a suction sidewall each extending between a core leading edge and a core trailing edge. A leading edge protective wrap protects the core leading edge and includes a trailing wrap and a leading wrap. The trailing wrap wraps around the core leading edge and is connected to the composite core. The leading wrap wraps around the core leading edge and is connected to the trailing wrap. The trailing and leading wraps both have leading edges that are spaced from one another. A filler is positioned between the leading edges of the trailing and leading wraps. A protective nose is connected to the leading edge of the leading wrap. The components of the leading edge protective wrap are formed of non-metallic materials.

Abstract: The present disclosure relates to a rotor assembly including a protective core. The rotor assembly according to an embodiment of the present disclosure includes a disk that is inserted into a rotating shaft and has a plurality of seating grooves in a circumferential direction thereof, a plurality of blades inserted into the seating grooves, respectively, and a protective core which is arranged between the blades and the disk, has a plurality of mounting portions on one surface thereof, and includes a plurality of weights that are attachable to and detachable from the mounting portions.

Abstract: In an impeller comprising a rotatable hub and a plurality of blades provided circumferentially on the rotatable hub at regular intervals, the blades including first blades each having a first vibrational eigenvalue and second blades each having a second vibrational eigenvalue, the first blades and the second blades are circumferentially arranged with a predetermined regularity in a circumferential direction in an alternating manner and with a mistune distribution that does not include a mistune component having a wavenumber twice a number of nodal diameters computed from H+ND=nN where H is a rotational order of resonance under harmonic forced vibration, ND is a nodal diameter number in a traveling wave mode, n is an integer and N is a number of the blades.

Abstract: A lock lug for inhibiting movement of a plurality of rotor blades includes a body and an engagement mechanism. The body is sized and configured to be received within the rim slot of the rotor disk and defines a dovetail receiving aperture. The engagement mechanism extends from the body and has a retracted configuration configured to allow entry and exit of a dovetail of at least one or more of the plurality of rotor blades into and out of the dovetail receiving aperture and an extended configuration configured to block the dovetail from entering the dovetail receiving aperture.

Abstract: A propeller provided with interchangeable blades, and to a method of mounting such interchangeable blades on the propeller. The propeller comprises a hub, fastening fittings, rotation guide devices for guiding the fastening fittings in rotation relative to the hub, locking parts, and blades. The fastening fittings are configured to be assembled into the hub from the inside of the hub, and the locking parts lock respective ones of the fastening fittings onto the hub. The blades are fastened to respective ones of the fastening fittings outside the hub and can thus easily be replaced with other blades without removing the propeller.

Abstract: A rotor assembly has: blades having airfoils and roots protruding from platform segments; a rotor disc having a peripheral face defining recesses, and slots, a recess located between two adjacent ones of the slots and bounded by a step; feather seals located radially between the peripheral face and the platform segments, a feather seal having a core extending from a trailing end to a leading end and overlapping a gap defined between two platform segments and tabs protruding from the core, the tabs including: trailing tabs positioned axially outside the recess; and leading tabs, a leading tab extending from a root to a tip and having one or more of: the tip axially positioned outside of the recess; and a fillet at an intersection between the tip and an edge of the leading tab, the edge extending between the tip and the core, and facing the step.

Abstract: A vibration damping system includes a vibration damping element for a turbine nozzle or blade. A body opening extends through the turbine nozzle or blade between the tip end and the base end thereof, e.g., through the airfoil among potentially other parts of the nozzle or blade. A vibration damping element includes a plurality of stacked plate members within the body opening. Each plate member is in surface contact with at least one adjacent plate member to cause friction that dampens vibration of the nozzle or blade. The body opening has an inner dimension, and each plate member has an outer dimension sized to frictionally engage the inner dimension of the body opening to damp vibration. Plate members may each include a central opening therein, and a fixed elongated body or cable may extend through the central openings. The damping element may alternatively include a helical metal ribbon spring.

Abstract: Morphable rotor blades for a turbine engine systems include a root portion and an airfoil portion having a morphable portion including a morphable material that changes shape in response to a stimulus.

Abstract: The present invention relates to a partly assembled structure in the form of a structure comprising a wind turbine tower, a nacelle arranged thereon and a vibration damper attached to the nacelle for damping vibrations of the combined wind turbine tower and nacelle within a selected frequency range, wherein the vibration damper is operatively connected to a main shaft of the nacelle, or wherein the vibration damper is attached to the nacelle via a nacelle transportation interface. The present invention further relates to a method of constructing a wind turbine and a method for damping Vortex induced vibrations of the combined wind turbine tower and nacelle within the selected frequency range.

Abstract: A damper element for a vibration dampening system may be used in a body opening in a rotating blade in a turbine. The damper element includes a base member having an axially fixed position within the body opening, and a spring-suspended bearing member having a spring fixedly coupled to the base member at a first end of the spring and a bearing member coupled to a second end of the spring. With the spring in an elastically extended state under influence of a centrifugal force caused by rotation of the rotating blade at higher than a predefined rotational speed, the bearing member frictionally engages a bearing surface to dampen vibration. The spring-suspended bearing member provides a friction-based vibration dampening interface that experiences a reduced impact of the centrifugal forces of the rotating blade by providing a counteracting force reduction using the spring.

Abstract: The present invention relates to a fan rotor with variable pitch blades, comprising a rotor disc, equipped at its periphery with a plurality of rotary fasteners (16), each fastener (16) comprising a cell (17) for receiving the root (150) of a blade (15).

Abstract: A rotor blade system. The rotor blade system includes a rotor and a plurality of blades coupled to the rotor. The plurality of blades are arranged in an airfoil distribution pattern. The airfoil distribution pattern includes one or more baseline blades and one or more intentionally mistuned blades including an intentional mistuning feature.

Abstract: A gas turbine engine comprising a set of circumferentially adjacent airfoils, the airfoils having an outer wall defining a pressure side and a suction side extending between a leading edge and a trailing edge to define a stream-wise direction, and between a root and a tip to define a span-wise direction, and a set of dimples provide on the outer wall of at least one of the airfoils, the set of dimples spaced in at least one of the stream-wise or span-wise directions.

Abstract: 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.

Abstract: An arrangement reduces oscillation (vibration) of an oscillatory structure. The arrangement has a structure having at least one mode in at least one direction; and an oscillation-reducing device (vibration-reducing device). The oscillation-reducing devices has a housing formed by or provided on the structure, a cavity, and a body configured for making impact contacts with the housing and disposed in the cavity in such a manner that the body is configured to make impact contacts with the housing at least temporarily for as long as the structure is excited in the at least one mode in the at least on direction.

Abstract: An arrangement reduces oscillation of an oscillatory structure. The arrangement has: a structure having at least one mode in at least one direction; and an oscillation-reducing device. The oscillation-reducing device includes a housing on the structure; a cavity; and a body. The body is configured to make impact contact with a first surface portion and a second surface portion of an inner wall of the housing and disposed is in the cavity such that the body can make impact contact with the first surface portion and the second surface portion of the inner wall of the housing at least temporarily for as long as the structure is excited in the at least one mode in the at least one direction. The first surface portion or the second surface portion of the inner wall of the housing has a curved profile.

Abstract: A composite platform for a fan of an aircraft turbine engine. The platform includes an elongate wall and is configured to extend between two fan blades. The wall includes an aerodynamic outer surface and an inner surface, on which a fastening tab is located, wherein the fastening tab is configured to be attached to a fan disc. The fastening tab is integrally formed with a metal reinforcement which has a plate having an elongate shape and which extends over more than 50% of the longitudinal extent of the wall, the wall being produced by overmolding a resin on the plate so as to be integrated into the wall.

Abstract: An integrally bladed rotor for a turbomachine, in particular a compressor or turbine stage of a gas turbine, to which at least one separately formed impulse element housing (40; 40?) is fastened by at least one fastening element (30; 30?) which engages for this purpose into an opening (41) of the impulse element housing and into an opening (11) of the rotor, the impulse element housing having at least one cavity (44) in which at least one impulse element (5) is accommodated with play.

Abstract: An aircraft turbomachine rotor has a rotor disc extending transversely with respect to a longitudinal axis X, a plurality of blades, and a damping device. The damping device having: a support ring arranged transversely with respect to the longitudinal axis X and mounted on the outer periphery of the rotor disc, and has a plurality of damping members that are attached to the support ring and project upstream from the support ring, each damping member being configured to extend at least under a platform of a blade so as to exert a radially outward force to dampen the radial movement of the blade when the turbomachine is in operation.

Abstract: A method of disassembling a rotor module of a gas turbine engine. The gas turbine engine having a rotor output shaft. The rotor module having a centre-bolt, a sleeve, at least one rotor stage, at least one stator stage, a casing and an axis. The method having the steps: attaching a fixture to the at least one rotor stage, attaching the fixture to the casing, detaching the centre-bolt from the at least one rotor stage, detaching the sleeve from the output shaft, attaching the fixture to the sleeve, and removing the rotor module and fixture from the rotor output shaft. There is also presented a method of assembling the rotor module to the gas turbine engine and the apparatus used for disassembly and assembly.

Abstract: Rotor blades, vibrational dampening elements, and methods are provided. A rotor blade includes a platform, a shank extending radially inward from the platform, and an airfoil extending radially outward from the platform. One or more fluid chambers are defined within the rotor blade. Glass is disposed within each fluid chamber of the one or more fluid chambers. A mass is disposed within each fluid chamber of the one or more fluid chambers. The mass is movable within the glass relative to the airfoil.

Abstract: An airfoil for use in a gas turbine engine is formed to define a cavity formed in the airfoil. The airfoil further includes at least one obstructing member arranged within the cavity and a shear-thickening fluid disposed in the cavity. A viscosity of the shear-thickening fluid increases in response to the airfoil experiencing an aeromechanic response or vibrations such that the obstruction of the movement of the thicker fluid by the obstructing member dampens the vibrations of the airfoil and reduces negative effects of a dynamic response of the airfoil.

Abstract: Water droplets that are moved on blade surfaces of a rotor blade are effectively guided toward the blade trailing edge while influence on the strength of the rotor blade is suppressed. A steam turbine rotor blade having a tie-boss for joining to adjacent blades at an intermediate position in the blade length direction is provided. The steam turbine rotor blade includes an airfoil part in which a blade surface is partly hollow as viewed in a section obtained by cutting by an orthogonal plane to a rotation center line of a turbine and a recessed blade surface that is this hollow partial blade surface passes through the blade root side of the tie-boss at least in a region on the pressure side and extends in a strip shape in the blade chord length direction.

Abstract: A vibration attenuator is configured for use on an aircraft rotor rotatable about a mast axis and has upper and lower weight assemblies, each comprising a weight with a center of gravity being a radial distance from the mast axis. The weight assemblies are configured for rotation together relative to the rotor at a selected angular rate about the mast axis, the weights being located on opposing sides of the mast axis. A first motor is configured for selective translation of one of the weight assemblies relative to the other weight assembly along the mast axis between a minimum-moment configuration, in which the centers of gravity of the weights revolve about the mast axis in the same plane, and a maximum-moment configuration, in which the centers of gravity of the weights revolve about the mast axis in different planes for producing a whirling moment about the mast axis.

Abstract: A yaw control system for a helicopter having an airframe that includes a tailboom includes one or more tail rotors rotatably coupled to the tailboom and a flight control computer implementing an airframe protection module. The airframe protection module includes an airframe protection monitoring module configured to monitor one or more flight parameters of the helicopter and an airframe protection command module configured to modify one or more operating parameters of the one or more tail rotors based on the one or more flight parameters of the helicopter, thereby protecting the airframe of the helicopter.

Abstract: A damper position-limiting device is provided, which is mounted in a tower to limit the swing amplitude of a damper installed in the tower. The damper position-limiting device includes at least one web and a position-limiting ring. The web is provided with a mounting hole and at least one stress relief hole. A first side wall of the web has a first specified length along a circumferential direction of the inner wall of the tower, and is connected to the inner wall of the tower. The position-limiting ring is positioned within the mounting hole and connected to the mounting hole and is configured to accommodate an impacting plate of the damper.

Abstract: Blades including integrated damping structures are disclosed herein. An airfoil to be disposed within a flow path of a gas turbine engine, the gas turbine engine defining an axial axis, a radial axis and a circumferential axis comprising an airfoil body including a first face, a second face and a recessed portion formed in the second face, and an airfoil cap having a first surface, the airfoil cap disposed within the recessed portion, the first surface substantially flush with the second face.

Abstract: A vibration damping system for a turbine nozzle or blade includes a body opening extending through a body of the turbine nozzle or blade between a tip end and a base end thereof. Elongated vibration damping element is disposed in the body opening and includes an elongated body having a first, free end and a second end fixed relative to one of the base end and the tip end. At least one wire mesh member surrounds the elongated body. The wire mesh member(s) frictionally engage with an inner surface of the body opening to damp vibration. A related method is also disclosed.

Abstract: A bottom-mounted whole house fan assembly includes an intake plenum mounted over an opening in a ceiling of a building. The intake plenum is supported on the ceiling in the attic of the building. One end of a flexible duct is connected to the intake plenum and the other end of the duct is connected to a fan so that the fan draws air in the building through the intake plenum and duct and exhausts the air in the attic from whence the air is vented to atmosphere. The fan is supported by at least one vertical strut that is connected to the ceiling at the lower end of the strut and to a housing of the fan at the upper end of the strut. A sound dampener is interposed between the strut and the fan housing and/or the ceiling beam to which the strut is attached.

Abstract: A vibration damping system for a turbine nozzle or blade includes a vibration damping element including a plurality of contacting members including a plurality of damper pins. Each damper pin includes a body. A wire mesh member surrounds the body of at least one of the plurality of damper pins. The wire mesh member has a first outer dimension sized for frictionally engaging within a body opening in the turbine nozzle or blade to damp vibration. Spacer members devoid of a wire mesh member may also be used. The damper pins can have different sizes to accommodate contiguous body openings of different sizes in the nozzle or blade. The body opening can be angled relative to a radial extent of the nozzle or blade.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed. An inner shroud damper for a gas turbine engine includes: at least one carrier including a joint to couple to an inner shroud, the at least one carrier having a first side and a second side, and at least one mass damper coupled to the at least one carrier.

Abstract: A gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a propulsor section including a propulsor, a turbine section including a first turbine and a second turbine, a compressor section driven by the turbine section, the compressor section including a first compressor and a second compressor, and a geared architecture driven by the first turbine. The propulsor is driven by the first turbine via the geared architecture. At least one stage of the turbine section includes an array of rotatable blades and an array of vanes. A ratio of the number of vanes to the number blades is greater than or equal to 1.55. A mechanical tip rotational Mach number of the blades is configured to be greater than or equal to 0.5 at an approach speed.

Abstract: An impeller includes Z blades, where Z is an integer equal to 5 or more, arranged in a circumferential direction of the impeller and extending radially, and pitch angles between adjacent blades are all different. In terms of an arbitrary pitch angle ?, when a pitch angle ?1 adjacent to the pitch angle ?, and a pitch angle ?2 adjacent to the pitch angle ?, different from the pitch angle ?1, satisfy a relation, ?1<?2, a pitch angle ?1 different from the pitch angle ? adjacent to the pitch angle ?1 and a pitch angle ?2 adjacent to the pitch angle ?2, different from the pitch angle ?, satisfy a relation, ?2<?1.

Abstract: A rotor for a hover-capable aircraft is described, comprising: a hub rotatable about an axis and, in turn, comprising a plurality of blades; a mast connectable to a drive member of the aircraft and operatively connected to the hub to drive the hub in rotation about the axis; and damping means for damping vibrations transmitted to the mast, which comprise a mass designed to oscillate in a plane transversal to the axis so as to contain flexural vibrations of the mast generated by rotation of the blades; the damping means also comprise elastic means having a desired stiffness along the axis and operatively connected to the mass to contain vibration of the mast along the axis.

Abstract: A turbine blade includes an internal vibration damping system having a plurality of unit cells. Each unit cell includes: an impacting structure; and a cavity encapsulating the impacting structure. The cavity, which includes a first hemisphere and a second hemisphere, is disposed within a substrate, which forms an outer casing of the cavity. At least one fluid is disposed in each of the first and second hemispheres between the impacting structure and the outer casing.

Abstract: A turbine wheel is provided with a groove having a bottom surface and a pair of side wall surfaces. The turbine wheel includes: a balance weight that is arranged in the groove, is insertable from any circumferential position of the opening of the groove, and has a through-hole opened toward one of the pair of side wall surfaces; and a retaining member that contacts the one of the pair of side wall surfaces in a state of being inserted in the through-hole of the balance weight, to thereby cause the balance weight to abut against the other one of the pair of side wall surfaces and be retained in the groove. The groove has engagement recesses provided at intervals in a circumferential direction at the bottom surface or an engagement protrusion fitted to one of fitting recesses provided at intervals in the circumferential direction at the bottom surface and protruding from the bottom surface.

Abstract: A rotor blade attached to a rotor shaft rotatable around an axis includes: a blade body extending in a radial direction with respect to the axis and having a blade-shaped cross section orthogonal to the radial direction; a shroud provided at an end of the blade body on a radial outer side, and a seal fin protruding from the shroud toward an outer circumferential side, and the seal fin includes: a seal fin body extending in a plate shape in a circumferential direction; and a reinforcing portion provided on at least one plate surface of the seal fin body to increase a thickness of the seal fin, the reinforcing portion gradually increasing in dimension in the radial direction toward the center in the circumferential direction.

Abstract: The invention relates to a torque transmitting device comprising a torque input element (17a, 17b) and a torque output element (8) able to pivot about a shaft (X) with respect to one another, at least one elastic leaf (22), rotationally coupled to the torque output element (8) or to the torque input element (17a, 17b) respectively, the elastic leaf (22) being able to be elastically and radially supported by a supporting member (18) carried by the torque input element (17a, 17b) or the torque output element (8) respectively, the elastic leaf (22) being able to bend upon rotation of the torque input element (17a, 17b) with respect to the torque output element (8).

Abstract: A blade (1) for a turbomachine, including a turbine blade (1.1) which has a channel (1.5), an impact chamber (2) having a constricted cross section being situated in the channel for the purpose of accommodating a single impulse body (3) is provided.

Abstract: An online real time steam or gas turbine engine rotor balancing system is incorporated in a rotor balance plane. A selectively displaceable balancing weight is coupled to the rotor and is selectively displaced by a motor that is coupled to the balancing weight. The motor selectively displaces the balancing weight along a displacement path that is in the balance plane. A turbine engine rotor vibration monitoring system monitors rotor vibration in real-time. A control system is coupled to rotor vibration monitoring system and the motor, for determining in real time a desired balance weight displacement position to counteract the monitored rotor vibration. The controller selectively causes the motor to displace the balancing weight to the desired displacement position. The motor power source is an inductive power source or a permanent magnet generator.