A set of compression stage(s) of a turbomachine, forming an annular fluid passage and comprising at least one annular stator platform and/or at least one annular rotor platform having an outer longitudinal profile inclined (I.sub.Si/I.sub.Ri) inwards and upstream with respect to a nominal profile of the fluid stream, where the inclination (I.sub.Si/I.sub.Ri) of the outer longitudinal profile of the or each of the annular platforms, relative to the nominal profile of the fluid stream, oscillates along the circumference of the annular platform or platforms, between a maximum value in front of the blades of the annular platform and a minimum value between each pair of adjacent blades of the annular platform.

A fan blade unit and a fan impeller structure thereof. The fan blade unit includes a main body having a root section and an end section. The root section is connected with a hub. The end section extends in a radial direction away from the hub. The end section defines a first direction and a second direction. Multiple protrusion bodies are disposed at the end section and at least one channel is formed between the protrusion bodies. The channel extends in the first direction. The fan blade unit is applied to the fan impeller structure. When the fan impeller rotates, a high-pressure area is created between the channel and the wall of the outer frame of the fan, whereby the airflow is restrained from turning over from the lower wing face to the upper wing face to generate wingtip vortex.

An air-sending device includes a propeller fan to rotate about a rotational axis, and a ducted bell mouth surrounding an outboard area of the propeller fan. The propeller fan includes a plurality of blades. Each of the blades includes, in its outboard portion, a reflexed part bent upstream of an airflow that is generated in the direction of the rotational axis by rotation of the propeller fan. In the propeller fan, within an area that is closer to the trailing edge than is the near mid-chord area, the propeller fan is inclined downstream of the airflow from the inboard edge to the reflexed part. In at least a portion of an area where the cylindrical part of the bell mouth and the outboard edge of each blade face each, the reflexed part has a reflex angle of greater than or equal to 90 degrees.

A cooling fan has a fan shroud with a fan wheel recess surrounded by a shroud ring and a fan wheel rotatably mounted in the fan wheel recess for conveying the air flow along a conveying direction from a shroud upper side to a shroud underside. The fan wheel has a central hub cup with radially orientated blades and an outer ring connecting the blades at the blade tip ends. A circumferential ring gap is formed between the outer ring and the shroud ring. A rib structure in the ring gap reduces swirl in a gap flow orientated against the conveying direction. A shroud ring section of the shroud ring extends axially beyond the outer ring on the shroud underside. The shroud ring section is orientated parallel or at an angle of inclination and radially inwards relative to the conveying direction.

A fan blade comprising a blade body spanning from a blade root to a blade tip in a longitudinal direction and a fluid passageway formed within the blade body and extending from the blade root to the blade tip. The blade body spanning from a leading edge to a trailing edge in a lateral direction. The fluid passageway allowing fluid to flow out of the blade.

A blisk 10 for a gas turbine includes a rotor blade row 12 extending around a central axis X and, axially spaced therefrom and extending coaxially therewith, at least one annular sealing fin 11. The sealing fin has a radially outer annular portion 111 that is thickened as compared to a radially more inward annular portion 113. A compressor 1 includes a rotor and a casing 30. The casing includes at least one stator vane row having at least one abradable liner. The rotor includes at least one blisk 10, whose at least one sealing fin 11 at least partly engages in the abradable liner. A turbine is constructed analogously. A method for manufacturing a blisk 10 for a gas turbine includes producing a blisk 10 having least one annular sealing fin 11, as well as applying a coating 116 to a radially outer surface 115 of a thickened annular portion 111 of sealing fin 11.

A ventilation device has a holder, in particular a ventilation frame, with a substantially circular continuous opening for receiving a ventilation wheel rotating about the central axis, thereof. The opening is bordered by an edge face running substantially cylinder-symmetrically about the central axis. As the edge face in two separate, diametrically opposed peripheral sections the radius is at least partly enlarged in comparison to the cylinder-symmetrical form in the remaining peripheral sections, and/or a circular projection of she edge face, which projection projects radially inwards, is axially offset away from a space provided for the ventilation wheel. Because of she corresponding shaping of the edge face of the opening, contact and/or development of noise between the ventilation wheel and the edge of the opening is prevented in the ventilation frame in the event of a yawing of the ventilation wheel.

The invention relates to a casing, particularly of an axial turbomachine compressor. This casing comprises a support of cylindrical overall shape made of composite material, a metal ring fitted by bonding to the internal surface of the support, and a layer of abradable material fitted by plasma spray onto the internal surface of the metal ring. The metal ring is preferably made of stainless steel and is preferably perforated. The perforation allows better keying of the adhesive and allows the degassing thereof. The external surface of the metal ring is preferably sandblasted prior to bonding. Its internal surface is also preferably sandblasted prior to the plasma spraying of the abradable material.

A blowing device includes an axil fan having a plurality of blades and causing an air to flow through the blowing device, and a fan shroud rotatably supporting the fan. The fan shroud includes a ring portion surrounding a circumference of the fan, and an air guide portion connecting an outer rim of the fan shroud and an inner rim of the ring portion. The fan shroud includes a specific rim portion that is a part of the outer rim of the fan shroud, a distance from the specific rim portion to the inner rim of the ring portion being shorter than other parts of the outer rim. The fan shroud includes a counter flow introduction passage provided in the air guide portion and extending from a position located inward of the specific rim portion. The blowing device is capable of limiting a rotation noise of the fan.

A coated substrate comprises: a metallic substrate; a bondcoat atop the substrate; and a ceramic barrier coat atop the bondcoat. The bondcoat has a combined content of one or more of molybdenum, chromium, and vanadium of at least 50 percent by weight.