Abstract: A method for cutting a preform usable for production of a turbomachine part and including a weaving of a plurality of threads, the threads including single threads that are visually identifiable, along a cutting contour calculated based on a preform model in which the threads have a reference arrangement, the method including: taking an image of the preform; processing the image to determine a deviation in an arrangement of the threads which are visually identifiable relative to the reference layout; correcting the cutting contour according to the deviation; and cutting the preform along the corrected cutting contour.

Abstract: A heat exchanger for an air circulation channel of a turbomachine, with the heat exchanger being configured to be passed through by a fluid to be cooled, is provided. The heat exchanger includes a plurality of fins protruding with respect to a support surface, each fin extends axially over a length in the direction of the circulation of air and includes a leading edge and a trailing edge. Each fin further includes a central body, between the leading edge and the trailing edge, with the central body having, in a plane parallel to the support surface, a curved central profile.

Abstract: A method for reducing the noise level generated by a fan of a turbomachine including a plurality of vanes, said method further including, when the turbomachine is operating and under given flight conditions, the following steps measuring an operational pitch angle for each of the vanes, calculating an offset between the operational pitch angle of each of the vanes and a predetermined reference pitch angle for the given flight conditions so as to produce a controlled noise level at multiple rotation frequencies of the fan, correcting the orientation of the vanes so as to compensate their operational pitch angles depending on the offsets thus calculated.

Abstract: The invention proposes a casing (30) of an aircraft turbine (16), intended to support a set of ring sectors (28) which partly delimits a channel for the passage of a gas stream through the turbine (16), where the casing (30) includes means for dynamic adjustment of the radial position of the ring sectors (28) by controlled injection of an air stream on to portions (36) of an annular wall (34) of the casing (30), where the casing (30) includes an upstream radial tab (38) which connects an upstream end of each ring sector (28), in the flow direction of the gas stream, to the casing (30), and a downstream radial tab (40) which connects a downstream end of each ring sector (28) to the casing (30), where both upstream and downstream radial tabs (38, 40) are made from a single piece with the casing (30), characterized in that each radial tab (38, 40) is made as two portions (42, 44) from different materials.

Abstract: A gearbox for driving equipment of a turbomachine, including a substantially V-shaped box having two arms joined together by a joining part, the arms containing gear trains joined together at the joining part, and an attachment to the turbomachine. The attachment include a mechanism for insetting and/or for attaching the joining part and a suspension device of the arms.

Abstract: A method for unscrewing a link nut of an HP rotor of a twin-spool turbine, including a front fan, an intermediate casing, a HP module with a HP rotor, and a LP turbine module, the intermediate casing including a support bearing for the HP rotor, the rotor being retained in the bearing by the link nut, the method including: placing an unscrewing tool in front of the link nut after having removed the fan and released access to the nut from the front; with rotation of the HP rotor locked and the frontal unscrewing tool including a socket spanner including teeth having a shape that complements that of teeth of the link nut, attaching a mounting for the socket spanner to the intermediate casing, the socket spanner being rotatably mounted on the mounting, and applying an unscrewing torque to the socket spanner. An unscrewing tool implements the method.

Abstract: A fuel dosing device for a fuel injector of an aircraft turbomachine, including an opening, a movable member for sealing the opening, and elastic return, with the member able to be displaced under the effect of the fuel pressure. The device includes a first outlet communicating with a primary circuit of the injector as well as a second outlet communicating with a secondary circuit. In addition, it is designed such that up to a defined level of displacement of the sealing member, the latter allows the fuel coming from the opening to reach the first outlet and, only beyond the defined level of displacement, the member allows the fuel coming from the opening to reach the second outlet.

Abstract: A method for inspecting an object by ultrasound transmission, including sweeping an ultrasound beam over a reference part that has the same geometry as the object to be inspected, and measuring the amplitude transmitted through the part to obtain a mapping thereof. The ultrasound beam is amplified with a reference gain. The method further includes determining gain corrections to be added to the reference gain at certain points during the sweeping of the reference part to obtain an ultrasound beam amplitude transmitted through the part which is constant at each point of the mapping, and sweeping an ultrasound beam over the object to be inspected and measuring the transmitted amplitude. The gain applied to the various points during the sweeping corresponds to the reference gain corrected on the basis of said corrections.

Abstract: A fiber structure includes a blank portion formed as a single part by three-dimensional weaving between a first plurality of yarn layers and a second plurality of yarn layers, the blank portion corresponding to all or part of a fiber reinforcement preform for a part made of composite material. Outside the blank portion, the fiber structure includes one or more two-dimensional fabric layers, each two-dimensional fabric layer grouping together the yarns of a single layer belonging to at least the first plurality of yarn layers and situated outside the blank portion.

Abstract: A method detects a failure in a fuel return valve of an aircraft engine fuel circuit. A fuel system is connected to a fuel tank of the circuit and includes a high-pressure pump delivering a flow rate to an actuating cylinder, a cutoff valve capable of feeding the actuating cylinder disposed in a feed pipe of the engine; a fuel return pipe; a fuel return valve arranged to switch between an open position and a closed position. The method includes starting the engine at an engine speed; increasing the engine speed until a flow rate reaches a predefined value sufficient for opening the cutoff valve; measuring the position of the actuating cylinder and an engine speed corresponding to the opening of said cutoff valve.

Abstract: A method for cutting a preform usable for production of a turbomachine part and including a weaving of a plurality of threads, the threads including single threads that are visually identifiable, along a cutting contour calculated based on a preform model in which the threads have a reference arrangement, the method including: taking an image of the preform; processing the image to determine a deviation in an arrangement of the threads which are visually identifiable relative to the reference layout; correcting the cutting contour according to the deviation; and cutting the preform along the corrected cutting contour.

Abstract: The invention relates to a replacement device (1) for replacing machining inserts (900) on a tool (800) comprising a body (810) and a head (820) carrying at least one machining insert (900), each insert being held on the head (820) by a screw.

Abstract: An air and fuel injection system for a turbine engine combustion chamber dome, including at least two fuel injection devices including a central injector and a peripheral annular injector arranged around the central injector, and an inner annular air inlet channel into which the central injector opens up to enable mixing between the fuel from the central injector and the air inlet into the inner annular channel, and at least one outer annular air inlet channel to enable enrichment of this mix with air and to stabilize the pilot combustion zone, wherein the inner annular channel and at least one outer annular channel are separated by an intermediate annular wall extending around the central injector and having a convergent inner profile.

Abstract: Aircraft turbomachine comprising at least one heat exchanger (40) and a gearbox (10) in a V-shaped overall configuration and comprising two lateral arms (20) joined together by a central joining piece, the heat exchanger being mounted between the arms of the gearbox.

Abstract: A propeller blade extending radially between a blade root and a blade tip and having a leading edge and a trailing edge, together with a pressure side face and a suction side face. Along the leading edge, the angle (?) between the radial direction and a tangent to the leading edge passes through a local maximum zmax situated in the range 60% to 80% of the height of the blade. Furthermore, the suction side face of the blade includes an indentation extending axially from the leading edge to the trailing edge and located at a height of the blade between the local maximum zmax and the blade tip.

Abstract: The present invention relates to a rotor for a turbomotor impeller, with variable-pitch blades, comprising blade roots capable of rotating in a blade supporting structure and a device for feathering the blades. Said feathering device comprises at least one flyweight secured to a crank connected by a gear set to at least one of said blade roots.

Abstract: A device for circulation of air for a turbomachine, the device including an inlet provided to receive incident airflow, air circulation ducts connected to the inlet, a central part including side walls, peripheral walls arranged at a distance from the central part, so as to form the air circulation ducts, each duct being arranged between one of the side walls of the central part and one of the peripheral walls, each peripheral wall including an upstream end portion delimiting with one of the side walls an inlet orifice of one of the ducts and a downstream end portion delimiting with one of the side walls an outlet orifice of one of the ducts, at least one member mobile in translation relative to the peripheral walls, the at least one mobile member being formed in the central part and arranged so that its displacement varies a section of each of the inlet orifices and a section of at least one of the outlet orifices.

Abstract: An afterbody for a turbojet engine having a central axis, provided with a nozzle comprising two doors facing each other between two lateral beams. The doors pivot around axes defining a pivot direction, between a retracted position, in which a middle portion of the downstream edge of the doors forms the edge of the outlet section of the nozzle combined with the downstream edges of the two lateral beams, and a deployed position, in which the middle portions of the downstream edges of the pivoting doors come together so as to block the channel between the two lateral beams in order to reverse the thrust of the turbojet engine gases. The edge of the outlet section of the nozzle further having a crown of noise-reducing chevrons alternating with indentations and the afterbody.

Abstract: This module (5) serves to filter a raw setpoint (N1_CMD_OP) for a corrector network (6) in a system (20) for regulating an engine. It comprises: a module (54) for detecting a filtering condition for filtering said raw setpoint; and means for supplying said corrector network with a filtered setpoint (N1_CMD_LIM) instead of said raw setpoint when the filtering condition is detected.

Abstract: A gas turbine engine for propulsion of an aircraft, the engine extending axially from upstream to downstream and including a composite part, a metal part, and a device for flexible fixing of the parts, the fixing device including: a flexible connecting element including a first fixing portion connected to the metal part by an axial connection and a second fixing portion connected to the composite part by an axial connection, the connecting element including an axially extending free end; and a rigid locking element including a fixing portion connected to the metal part by an axial connection and an axially extending free end, the free end of the locking element being aligned radially with the free end of the connecting element to limit deformation of the connecting element while the engine is in operation.