Abstract: An impeller includes: a disk that has a disk shape and is configured to rotate around an axis; and a plurality of blades that are provided at intervals in a circumferential direction on a side of a surface of the disk toward a direction of the axis and extend to a rear side in a rotation direction as the plurality of the blades go toward an outer side in a radial direction. Each of the plurality of the blades has: a primary blade which extends to the rear side in the rotation direction as the primary blade goes from an inner side toward the outer side in the radial direction, and a secondary blade which is provided at intervals on a side in front of the primary blade in the rotation direction to correspond to the primary blade.

Abstract: A vane configured to be placed with a plurality of identical vanes so as to form a vane wheel for an aeroengine, the vane wheel defining an axis, the vane having an airfoil presenting a leading edge and a trailing edge, the leading-edge curve describing the shape of the leading edge of the airfoil in a view perpendicular to the airfoil presenting at least one leading-edge undulation, said at least one leading-edge undulation extending over less than 30% of a length of the airfoil from the first end of the airfoil.

Abstract: A variable nozzle unit includes a variable nozzle vane which is disposed between a hub wall surface and a shroud wall surface and is rotatable around a rotation axis parallel to a rotation axis of a turbine impeller inside a gas flow passage. The variable nozzle vane includes a leading edge, a trailing edge, and an outer vane surface connecting the leading edge and the trailing edge and facing a radial outside of the rotation axis. A concave portion at least in a range of a leading edge side in relation to the rotation axis is formed at the hub wall surface side of the outer vane surface.

Abstract: A mixed-flow impeller for an electric submersible pump can include a lower end and an upper end; a hub that includes a through bore that defines an axis; blades that extend at least in part radially outward from the hub where each of the blades includes a leading edge and a trailing edge; an upper balance ring that includes a radially inward facing balance chamber surface and a radially outward facing diffuser clearance surface; and an upper guard ring disposed radially outwardly from the upper balance ring where the upper guard ring includes an axially facing diffuser clearance surface that is disposed axially between the trailing edges of the blades and the upper end.

Abstract: A height-adjustable fan fixing structure and a height adjustment method are provided. The height-adjustable fan fixing structure includes a fan box rear cover and a fan box front cover, the fan box rear cover and the fan box front cover cooperating to fix a fan; and further includes a height adjustment block, the height adjustment block being adjustably mounted on a whole piece formed by connection of the fan box rear cover and the fan box front cover, the lower end of the two side surfaces of the height adjustment block being provided with trunkings, each of the trunkings being provided with a rotatable wire screw, positions, corresponding to the two ends of each wire screw, on the fan box rear cover and the fan box front cover being provided with clamping holes, the two ends of the wire screw being inserted into the clamping holes.

Abstract: A rotor hub is presented that uses a low profile and frontal area design that reduces drag and combines the advantages of utilizing a virtual flapping hinge and a soft in-plane rotor hub.

Abstract: An inlet guide vane includes: a movable vane that has a vane main body and a shaft portion disposed in an end portion of the vane main body; a frame that has an insertion hole into which the shaft portion is to be inserted; a plurality of bearing portions that are arranged inside the insertion hole at an interval in a direction of a central axis of the shaft portion and that support the shaft portion to be rotatable around the central axis with respect to the frame; and a seal portion that is located inside the insertion hole between the plurality of bearing portions in the direction of the central axis and that seals an area between the insertion hole and the shaft portion.

Abstract: A gas turbine engine includes rotor having a hub, and a plurality of blades extending generally radially from the hub. Each of the blades has an airfoil portion. The airfoil portion has a leading edge and a trailing edge defining a chordwise direction, and a root and a tip defining a spanwise direction. Only a sub-set of the blades has a cutback at at least one of the trailing edge and the leading edge. A method of designing and a method of assembling a rotor having noise reduction properties in a gas turbine engine is also presented.

Abstract: An air seal may comprise an annular ring defined by at least a proximal surface, a distal surface, an aft side and a forward side. A channel may be disposed in the forward side of the air seal and/or the aft side of the air seal and may extend between the proximal surface and the distal surface. An additional channel extending from at least one of the forward side or the aft side may be disposed in the distal surface. The channel and the additional channel may be circumferentially in line. The channels may define a flow path for direction cooling air from a proximal side of the air seal to a distal side of the air seal. The radial channel may interface with the axial channel at an edge of the air seal.

Abstract: A wind power installation with a tower, an aerodynamic rotor, wherein the aerodynamic rotor can be operated with a variable rotor speed and has a number of rotor blades respectively with an adjustable rotor blade angle, a generator for generating an electrical output power, wherein for operating the wind power installation an operating characteristic, which indicates a relationship between the rotor speed and the output power, is specified and a controller, which sets the output power in a way corresponding to the operating characteristic in dependence on the rotor speed, is provided, wherein selectable as the operating characteristic is a reduced-tonality operating characteristic, which is designed such that an excitation of a system resonance of the wind power installation is reduced as compared with an optimum-power operating characteristic, without however excluding a speed that excites this system resonance.

Abstract: A wind turbine comprising a pod and an aerodynamic rotor having a rotor head or a spinner. The rotor head or spinner is arranged in that case in the afflux flow direction of the wind in front of the rotor blade plane. Provided in or at the rotor head or the spinner of the rotor is a mist eliminator which rotates with the rotor head or spinner. The mist eliminator has an end which is in the form of an opening in the rotor head or the spinner. Air can enter through that end and flow through the mist eliminator in such a way that substantially water droplet-free air is present at the outlet of the mist eliminator, and can be used for cooling the generator.

Abstract: Controller for controlling a bleed valve including a first body with an internal cavity connected to an air inlet port and an air outlet port, a second body including a chamber, a mobile member in the cavity and in the chamber, connecting the two bodies. The member is mobile between a position whereby the ports fluidly communicate and a position whereby the ports are isolated, the member further including two pistons housed in the chamber and defining in this chamber at least two spaces. The controller also includes a fluid supply for at least one of the spaces for the purpose of moving the pistons in the chamber.

Abstract: A wind turbine blade is provided with two shell parts each at least partly made of a sandwich structure including an inner skin (76), an outer skin (74), and an intermediate core material (75, 77), wherein the shell parts are bonded together at least along their respective leading edges (18). The blade also comprises a longitudinally extending spacing section in which the respective trailing edges (58a, 58b) of the pressure side shell part and the suction side shell part are spaced apart, wherein a trailing edge shear web (45) is arranged between and connected to the sandwich structure of the suction side shell part (84, 86, 87) and the sandwich structure of the pressure side shell part (74, 76, 77).

Abstract: Provided is a centrifugal compressor impeller that includes: a hub; a plurality of full blades that are arranged on the hub in a circumferential direction of rotation; and splitter blades provided between the full blades. There is a line-of-sight direction which is a direction parallel to a virtual plane perpendicular to a rotation axis and in which an entire suction surface of the full blade adjacent to a front side of the splitter blade in a rotational direction, an entire pressure surface of the full blade adjacent to a rear side of the splitter blade in the rotational direction, and an entire surface of the splitter blade are visible.

Abstract: An air seal for a jet turbine engine with an upper stator, lower stator and finned turbine disk. The thermal expansion of the stators may be regulated by a control ring, which has a lower rate of thermal expansion that the stators, to prevent rubbing between the stator and fins.

Abstract: A small gas turbine engine with a ceramic turbine to allow for higher turbine inlet temperatures, where a metallic compressor is secured to a ceramic shaft extending from a ceramic turbine to form a single piece ceramic shaft and turbine, where a threaded nut secures a split ring retainer on the compressor end of the ceramic shaft. A hollow thrust runner is compressed between the compressor disk and the turbine disk by the threaded nut to secure rotor together. A centering spring forms a tight fit between the metallic thrust runner and the ceramic shaft on the turbine side.

Abstract: The invention concerns a transition duct for a multi-stage compressor of a gas turbine engine. Regions of the inner surface of the duct are provided with a predetermined and dissimilar surface roughness to optimise gas flow efficiency within the duct.

Abstract: An airfoil and shroud assembly includes an airfoil including a root end, a free end and a tenon extending from the free end, the tenon including a base and an externally threaded stud extending from the base. A shroud includes an opening configured to receive the base of the tenon. A nut is configured to be threadably coupled to the externally threaded stud on the tenon on the airfoil to couple the shroud to the airfoil.

Abstract: A pressure relief arrangement for a gas turbine engine comprises a hinged door and a mount. A plastically deformable member is provided between and coupled to the hinged door and the mount. The deformable member is configured to deform between a non-deformed state when the door is in a closed position and an elongated deformed state when the door is in an open position.

Abstract: A centrifugal compressor includes: a rotor that includes a shaft rotatably disposed inside a casing and impellers fixed to an outer periphery of the shaft; a diaphragm that surrounds the impellers from an outer peripheral side; a suction-side casing head disposed separately from the diaphragm on a side on which fluid is sucked; a temperature controlling mechanism that is provided inside the suction-side casing head and is configured to control ambient temperature through flow of a heating medium; a heat insulating body disposed between the suction-side casing head and the diaphragm; and a locking structure that locks the heat insulating body and the suction-side casing head with each other to be relatively displaceable in a radial direction.