Abstract: In some examples, acoustic panels (such as for gas turbine engines) and techniques for forming acoustic panels. In some examples, the acoustic panel including a coversheet including an outer face, an inner face, and a plurality of apertures extend from the outer face to the inner face. The acoustic panel also includes a 3D-printed support layer including a lattice structure formed at least partially of a polymer, the lattice structure defining a plurality of cells of the support layer, wherein a first side of the support layer is coincident with the inner face of the coversheet.

Abstract: A method of a coating by additive manufacturing on a turbomachine casing includes depositing on an internal surface of the turbomachine casing a filament of an abradable material to create a three-dimensional scaffold of filaments. A filamentary material deposition system is positioned from the internal surface of the casing; a first layer of the coating is deposited over 360?; a rotation of the filamentary material deposition system is carried out by a first predetermined angle and the filamentary material deposition system is positioned from the deposited layer; a second layer of coating is deposited on the first coating layer, on a sector of the casing; a displacement is carried out corresponding to the first sector already covered, then for the following sectors until 360° is covered; and after having carried out a rotation of the filamentary material deposition system.

Abstract: A manufacturing method of an abradable coating consisting of depositing, on a substrate surface a filament of a thermosetting material while providing both a relative displacement between the substrate and the filament along a predetermined deposition path and solidification of the filament in order to create a three-dimensional scaffold of filaments, consisting of superimposed layers of which the filaments of a given layer are not contiguous and can be oriented differently from those of an adjacent layer, so as to confer upon it acoustic wave absorption properties, the thermosetting material being a thixotropic mixture free of solvent and consisting of a polymer base and a cross-linking agent in a weight ratio of a polymer base to a cross-linking agent comprised between 1:1 and 2:1, and of a flowing component, typically a petroleum jelly present between 5 and 15% by weight of the total weight of the thixotropic mixture.

Abstract: A co-curable thermoset acoustic liner and method of forming the same includes a sound attenuating core having a plurality of core cells. An inner face sheet having a plurality of face sheet apertures is coupled to the core by an inner thermoset adhesive sheet, which has a plurality of adhesive sheet apertures. Each of the plurality of adhesive sheet apertures is aligned within a corresponding one of the plurality of face sheet apertures so that the plurality of core cells are placed in fluid communication with airflow over the inner face sheet to create a Single Degree of Freedom (SDOF) acoustic liner.

Abstract: The invention relates to an aircraft turbine engine module (10), comprising a degassing tube (14) and an ejection cone (12). The tube and the cone comprise centring means engaging together. The invention also relates to a locating and adjusting tool for assembling said module.

Abstract: A processing apparatus is provided. The processing apparatus includes a processing chamber having a gas outlet. The processing apparatus further includes a pump. The pump communicates with the gas outlet and is configured to exhaust gas from the processing chamber via the gas outlet. The processing apparatus also includes an intersecting module. The intersecting module includes a number of support members and a number of internal ventilating plates. The support members are arranged along a longitudinal direction, and each of the internal ventilating plates has a number of orifices. At least one of the internal ventilating plates is positioned between two of the support members positioned adjacent to each other.

Abstract: A composite structure assembly and method of forming a composite structure assembly is provided. The composite structure assembly includes a composite core including a first cell layer having a plurality of first cells and a second cell layer having a plurality of second cells. The first cell layer is adjacent to the second cell layer. The plurality of first cells are fluidly interconnected with the plurality of second cells.

Abstract: The present disclosure provides a turbocharger which reduces noise generated from the wastegate. The turbocharger includes a turbocharger housing, a rotary assembly, and a wastegate door. The turbocharger housing defines a wastegate opening, a resonator proximate to the wastegate opening, a compressor inlet, a compressor outlet, a turbine inlet, and a turbine outlet. The rotary assembly includes a turbine and a compressor attached to one another by a shaft wherein the rotary assembly is disposed in the turbocharger housing. The wastegate door may be moveably affixed to the turbocharger housing.

Abstract: An example method for manufacturing a multicellular structure for acoustic damping is described that includes applying a porogen material to a solid support, inserting a multicellular frame into the solid support and through the porogen material so as to fill cells of the multicellular frame with the porogen material, fusing the porogen material, removing the multicellular frame from the solid support, and the multicellular frame contains a suspended fused porogen network attached to walls of the cells of the multicellular frame. The method also includes applying a solution to the suspended fused porogen network in the cells of the multicellular frame to percolate the suspended fused porogen network, curing the solution, and removing the suspended fused porogen network from the multicellular frame resulting in porous septum membranes of the cured solution in cells of the multicellular frame.

Abstract: A sandwich component for a motor vehicle includes a core layer, at least two fiber layers, and at least one layer of matrix material applied onto the upper and/or lower side of at least one of the fiber layers. The matrix material is applied in different ways onto at least two of the fiber layers and/or in different ways onto at least one of the fiber layers along the upper and/or lower side thereof.

Abstract: A method of controlling plume exhaust heat and/or noise radiation from a turbofan engine assembly having a short nacelle. A mixer duct shell is supported such that a downstream edge of the short nacelle overlays an upstream portion of the mixer duct shell. A first portion of fan exhaust may be routed through the mixer duct shell between its inner surface and an outer surface of a core engine shroud. A second portion of fan exhaust may be routed over an outer surface of the mixer duct shell. At least one of the inner surface and an outer surface of the mixer duct shell may have an acoustic lining including a honeycomb core structure.

Abstract: An acoustic device includes a first member; a second member; a cavity formed by joining the first member and the second member together; and a port to communicate the cavity with an outside. The port is disposed at a joint portion between the first member and the second member. The first member includes a bottom plate disposed opposite the second member with the cavity in between and a side wall extending from the bottom plate toward the second member, and an edge face of the side wall, opposite the bottom plate, contacts the second member, to form different cavities. The acoustic device further includes a hole that penetrates the side wall and a material of the second member has a density greater than that of the first member.

Abstract: An exhaust flue includes an exhaust chimney body, and an open end multi-hole area. The exhaust chimney body defines a passage for discharging exhaust gas. The open end multi-hole area is an area in which multiple holes are defined around a total circumference of an open end of the exhaust chimney body.

Abstract: An aircraft auxiliary power unit sound attenuation apparatus includes a perforated body having a center aperture through which exhaust fluid passes, a backing member outwardly offset from the perforated body, a plurality of connecting members coupling the perforated body to the backing member to form a locally reacting sound attenuation member having a plurality of channels spanning outwardly from the perforated body to the backing member, and a bulk absorber disposed in each of the plurality of channels where the bulk absorber is in fluid communication with the exhaust fluid, where the locally reacting sound attenuation member is in fluid communication with an auxiliary power unit of an aircraft so that the plurality of channels are oriented in a direction crossing a pressure drop direction of an exhaust fluid flow passing through the center aperture and each channel circumscribes the center aperture.

Abstract: An inner bypass duct of a gas turbine engine includes a plurality of non-structural front panels arranged circumferentially. Each front panel has an outer surface and an inner surface. The inner surface is at least partially covered by a composite structure. The composite structure includes a fireproof layer and an acoustic layer disposed between the fireproof layer and the inner surface. A non-structural panel for an inner bypass duct and a method of forming such panel are also presented.

Abstract: The invention relates to a damper for reducing pulsations in a gas turbine, which includes an enclosure, a main neck extending from the enclosure, a spacer plate disposed in the enclosure to separate the enclosure into a first cavity and a second cavity and an inner neck with a first end and a second end, extending through the spacer plate to interconnect the first cavity and the second cavity. The first end of the inner neck remains in the first cavity and the second end remains in the second cavity. A flow deflecting member is disposed proximate the second end of the inner neck to deflect a flow passing through the inner neck. With the solution of the present invention, as a damper according to embodiments of the present invention operates, flow field hence damping characteristic in the second cavity constant regardless the adjustment of the spacer plate in the enclosure.

Abstract: A structural panel for an aircraft nacelle may comprise a core between a perforated skin and a septum. A plurality of dividing walls may extend between the septum and a backskin to define a plurality of cavities. Each cavity may be in fluid communication with a plurality of cells in the core through the septum. The cells and the cavities may attenuate noise.

Abstract: A sound generator (1) includes a casing (10) with at least one exhaust gas inlet (11) and at least one exhaust gas outlet (12) that is different from the at least one exhaust gas inlet (11) and at least one electro-acoustical transducer (20). The electro-acoustical transducer (20) is configured to produce sound in dependence on an electrical control signal. The electro-acoustical transducer (20) is located within the casing or directly attached to the casing. An active noise control system (9) includes the sound generator (1). A vehicle (8) with an internal combustion engine (6) includes the active noise control system (9).

Abstract: A bypass turbojet including a fan wheel carrying blades and surrounded by an annular casing, the casing including an air suction mechanism sucking air from an annular clearance formed between the casing and radially outer ends of the blades of the fan wheel. The air suction mechanism includes an inlet including at least one inlet slot formed in an inside wall of the casing and connected to a suction channel extending downstream. The inlet slot of the suction mechanism is situated axially in register solely with upstream portions of chords of the blades of the fan wheel at their radially outer ends.

Abstract: A fume extractor hood is disclosed, comprising a box with a motor-fan assembly and a muffler module comprising a bearing frame defining an air extraction conduit with axis (A), an active noise suppression system comprising at least one electro-acoustic transducer and at least two microphones, a passive noise suppression system comprising a sound absorbent material. Said muffler module comprises at least two electro-acoustic transducers connected to the walls of said bearing frame, in opposite positions, in such manner to leave the central part of said conduit free. The sound beams coming from said at least two electro-acoustic transducers are mutually combined, obtaining a resulting sound beam that can be directed towards a preferred direction by means of beam forming algorithms.

Abstract: A sandwich material having both structural strength and significant acoustic attenuation. In one embodiment, a sandwich is composed of an architected core secured between two facesheets, with a compliant layer forming the connection between the core and the facesheets. The compliant core has a low modulus, resulting in a low speed for elastic shear waves in the sandwich, at low static loads. At high static loads the compliant material stiffens and allows the sandwich to exhibit significant structural strength.

Abstract: An aircraft nacelle including a pipe (32), a peripheral wall (34), a lip (36), and a front frame (38) connecting the peripheral wall (34) and the pipe (32) and forming with the lip (36) a space (50) in which the hot air that is provided for frost treatment can circulate, with the pipe (32) including a coating (44) for the composite material acoustic treatment, is characterized in that the nacelle includes at least one element (52) made of a heat-conducting material inserted between the lip (36) and the pipe (32) ensuring the continuity of the aerodynamic surfaces of the lip (36) and the pipe (32) and the propagation of heat from the space (50) toward the rear of the nacelle, whereby the at least one element (52) includes a coating (54) for acoustic treatment that is made of a heat-resistant material.

Abstract: A high-bypass gas turbine engine includes a variable area fan nozzle with an acoustic system having an acoustic impedance.

Abstract: An exhaust cone for an aircraft turbojet engine includes a front part which has a front end and a rear end. The front end is equipped with a front connecting flange connecting to an outlet of a turbojet engine and the rear end is equipped with a rear connecting flange connecting to a rear part of the exhaust cone. In particular, the front part is further equipped with a sound attenuation structure including an outer skin, and the outer skin overlaps the front connecting flange and the rear connecting flange.

Abstract: A muffler for a vehicle exhaust system includes a first outer shell, a second outer shell that cooperates with the first outer shell to define a muffler interior cavity, and at least one porous partition that separates the muffler interior cavity into at least first and second sub-cavities. In one example, the porous partition is integrally molded with at least one of the first and second outer shells. In one example, an exhaust tube extends through the first sub-cavity and acoustic fiber material is located within the first sub-cavity.

Abstract: A sound attenuating chimney element for a turbomachine system includes a high density outer body having an external surface and an internal surface, and one or more acoustic attenuation layers provided on the external surface of the outer body. The one or more acoustic attenuation layers include an outer surface portion and an inner surface portion. A structural layer is provided on the outer surface portion of the one or more acoustic attenuation layers. The structural layer includes an external surface that defines a duct configured and disposed to pass gases from the turbomachine system.

Abstract: An acoustic panel includes a first cellular layer with cells having a first axis, a second cellular layer with cells having a second axis, and a perforated septum layer separating the first layer and the second layer. The cells of both layers have an end distal to the septum layer and an end which meets the septum layer, and the maximum diameter of the cells of the first layer is less than the maximum diameter of the cells of the second layer.

Abstract: An engine-driven power generator apparatus, which includes, within a case, an engine and a power generator drivable with the engine, and in which an operation panel is provided on a front cover and an air intake louver for introducing air into the case is provided within the case, includes: a waterproof cover covering the operation panel and the air intake louver; an air guide passage of a labyrinth shape provided within the waterproof cover and communicating the outside of the waterproof cover with the air intake louver; and a brush-shaped water separation unit provided in the air guide passage and having a plurality of pins projecting in a direction intersecting flows of air in the air guide passage.

Abstract: The invention relates to an acoustic skin (22) for an aircraft nacelle acoustic panel, said skin including a plurality of layers (105, 106) stacked with composite planar bands (102) that are each directed by the direction-defining longitudinal axis (107) thereof, the longitudinal axes (107) of the bands (102) of a single layer (105, 106) being parallel therebetween, said bands (102) of said single layer (105, 106) being spaced from each other so as to have acoustic openings within the acoustic skin. The invention relates to a panel including such a skin, to a method for manufacturing said skin, and to a drape-forming head for implementing the method.

Abstract: The invention relates to an acoustic panel (20) for an ejector nozzle (10) comprising the following main components: an external skin (22) containing acoustic holes (29); an internal skin (23); an acoustic structure (21) comprising alveolar-core cells (27) between the internal skin (23) and the external skin (22). At least one main component selected from the external skin (22), the internal skin (23) and the acoustic structure (21) is formed by a composite material and the acoustic structure (21) is held in contact with either or both of the internal (23) and external (22) skins by compression by elastic means and/or by fixing by mechanical fixing means (24). The invention also relates to an injector nozzle (10) and a nacelle (1) comprising such an acoustic panel (20).

Abstract: A filter silencer is disclosed. In a particular embodiment, the silencer includes a housing, a silencer chamber disposed inside the housing, and a filter chamber disposed between a sidewall of the housing and the silencer chamber. An intake port is in communication with the filter chamber and ambient air. The filter chamber also includes a filter chamber outlet that is in communication with a compressor or air blower, for example. A silencer chamber inlet is in communication with an exhaust of the compressor or air blower, where an air flow is forced through the silencer and out a discharge port. The discharge port and the intake port are at opposing ends of the silencer. In addition, the silencer includes at least one baffle secured within the silencer chamber, where the baffle is configured to generate a non-directional interference with the air flow to assist in silencing the discharge.

Abstract: An intake silencer of a gas turbine capable of efficient noise reduction in which a high frequency sound-absorbing splitter group composed of a plurality of sound-absorbing splitters capable of reducing highfrequency component noise and a middle/low sound-absorbing splitter group composed of a plurality of sound-absorbing splitters capable of reducing middle/low frequency component noise are disposed separately in a gas flow direction. High frequency component noise is reduced by the high frequency sound-absorbing splitter group, and middle/low frequency component noise is reduced by the middle/low sound-absorbing splitter group.

Abstract: Honeycomb sections are bonded together with seams made up of an adhesive that is carried by a honeycomb seam support or a linked-segment seam support. The seams are particularly useful for splicing together curved honeycomb sections that contain acoustic septum. The curved acoustic honeycomb sections are spliced or seamed together to form engine nacelles and other acoustic dampening structures.

Abstract: The present invention relates to improvements in or relating to pump installations, It has particular relevance in the field of reciprocating piston pumps, such as condensate removal pumps which are used to remove condensate from air conditioning installations. We describe a liquid pulse damping device (20) comprising a body (21) having an inlet (22) and an outlet (23) in fluid communication. Intermediate the inlet and outlet is at least one liquid flow direction changing element (24, 25). Preferably, the at least one flow direction changing element (24, 25) is in the form of an elongate element having a closed end (30, 31) and a side wall, suitably a cylindrical side wall, having at least one bore (40) formed therethrough.

Abstract: The present invention provides an acoustic attenuation based on sound ray deflection theory and a muffler. The method of the present invention provides a temperature gradient between the interior and the exterior of the chamber of the muffler through the low temperature refrigeration system, in which the temperature inside the pipe wall is higher than that outside the pipe wall. The said temperature gradient may deflect the acoustic ray towards the low temperature direction, so as to capture and reduce the noise.

Abstract: A muffler having an inlet and an outlet, through which exhaust gas flows; a tubular main body; a heat exchanger inside the main body; a noise-deadening first conduit, which extends at least partly inside the main body, from a fork region located directly downstream from the inlet, to a converging region directly upstream from the outlet; a second conduit, which extends through the heat exchanger and at least partly inside the main body, from the fork region to the converging region and parallel to the first conduit; and a regulating valve located outside the main body, to selectively direct exhaust gas flow along the first conduit or the second conduit.

Abstract: A flexible muffler for use in an aircraft environmental system includes a flexible body having a porous inner layer and an air impervious outer layer both supported by a helically wound adhesively attached reinforcing cord. The flexible body includes a pair of connecting end caps at opposed ends thereof which are joined to the flexible body in an air tight attachment. The resulting muffler provides acoustic energy absorptive and is readily flexed and bent to accommodate space restrictions within the environmental control system of the aircraft.

Abstract: The present invention relates to an exhaust gas treatment unit for an exhaust system of a combustion engine, in particular of a motor vehicle, includes a housing, a plurality of exhaust gas treatment elements, which are arranged in the housing and through which a parallel flow is possible. The unit further includes an outlet nozzle, which penetrates a side face of the housing, and an outlet space disposed in the housing, whereby the outlet of at least one of the exhaust gas treatment elements opens into the outlet space. The rigidity and/or effectiveness of the exhaust gas treatment unit can be improved by means of a funnel body disposed in the outlet space, and comprising a funnel surface which is permeable to exhaust gas. The funnel body connects an outlet end of one of the exhaust gas treatment elements with the outlet nozzle.

Abstract: The invention relates to an acoustic skin (22) for an aircraft nacelle acoustic panel, said skin including a plurality of layers (105, 106) stacked with composite planar bands (102) that are each directed by the direction-defining longitudinal axis (107) thereof, the longitudinal axes (107) of the bands (102) of a single layer (105, 106) being parallel therebetween, said bands (102) of said single layer (105, 106) being spaced from each other so as to have acoustic openings within the acoustic skin. The invention relates to a panel including such a skin, to a method for manufacturing said skin, and to a drape-forming head for implementing the method.

Abstract: Methods and devices for increasing the sound attenuation properties of a noise suppression device are provided. In some embodiments, a sound attenuating conduit has an improved shape that provides increased sound attenuation properties. In other embodiments, the sound attenuating conduits are stacked together, and shaped to increase the air flow cross-section. Still other embodiments provide machinery that includes the improved sound attenuating conduits.

Abstract: A sound damper for compressed air systems of vehicles includes a housing, an insulator and at least one web. The housing has an air inlet and an air outlet. The insulator is located in the housing, and the web is located in the housing such that it protrudes at least partially into the insulator. Air that flows through the housing from the air inlet to the air outlet is conducted by the web into the insulator.

Abstract: A sonic absorption device for an air pipeline of an aircraft, which sonic absorption device comprises at least one curved pipe section whose respective interior wall is clad with a sound absorption material, wherein within the curved pipe section at least one air guidance means is arranged for a flow optimization, wherein for further weight-neutral sound absorption the air guidance means arranged within the curved pipe section comprises a microperforation on at least one side surface.

Abstract: A composite structure and an associated exhaust washed structure are provided which may be formed of ceramic matrix composite (CMC) materials. A method of fabricating a composite structure which may include the CMC material is also provided. A composite structure may include a corrugated septum extending in a lengthwise direction. The composite structure may also include a flute within which the corrugated septum is disposed to form, for example, a partitioned flute assembly.

Abstract: The invention relates to an acoustic panel (20) for an ejector nozzle (10) comprising the following main components: an external skin (22) containing acoustic holes (29); an internal skin (23); an acoustic structure (21) comprising alveolar-core cells (27) between the internal skin (23) and the external skin (22). At least one main component selected from the external skin (22), the internal skin (23) and the acoustic structure (21) is formed by a composite material and the acoustic structure (21) is held in contact with either or both of the internal (23) and external (22) skins by compression by elastic means and/or by fixing by mechanical fixing means (24). The invention also relates to an injector nozzle (10) and a nacelle (1) comprising such an acoustic panel (20).

Abstract: A duct 26 has circumferentially distributed features capable of scattering acoustic energy associated with fluid dynamic shocks 34 extending in a shock orientation direction D. Each feature is oriented, over at least a portion of its length, substantially perpendicular to the shock orientation direction. The features may be splices 42 used to connect segments of an acoustic liner 30, partitions 56 in a stability enhancing casing treatment 32, or other features capable of scattering acoustic energy associated with shocks.

Abstract: An acoustic inner barrel for an aircraft engine nacelle inlet is constructed from a composite material and is formed as a single, 360-degree annular segment. The barrel includes an inner skin, an outer skin, a cellular core disposed between the inner skin and the outer skin, and at least one crack and delamination stopper extending radially from the inner skin to the outer skin.

Abstract: A silencer for a CPAP device comprises a housing assembly defining a flow path passing therethrough and including at least one of an inlet chamber, an acoustic chamber and a blower chamber. Each of the chambers has an inlet and an outlet for fluid communication therebetween. The silencer includes a combination of reactive components, resonators and dissipative elements disposed within the inlet, acoustic and blower chambers. The reactive component may be configured as a compliant-walled reactive tube. The resonator may be configured as a perforated plate defining a cavity volume. The dissipative element may comprise porous material substantially occupying the cavity volume bounded by the perforated plate in the chamber walls.

Abstract: A process for the production of an acoustically resistive structure that can be inserted in an alveolar structure so as to obtain a coating for the acoustic treatment, whereby the acoustically resistive structure includes at least one porous layer (34) and at least one reinforcement structure (36) assembled by gluing, the process including: applying an amorphous-type adhesive on the at least one reinforcement structure (36), perforating or micro-perforating the reinforcement structure (36) after the application of the amorphous-type adhesive, and applying the at least one porous layer against the face of the reinforcement structure (36) that is coated with amorphous-type adhesive.

Abstract: The invention relates to a method for reducing the noise missions from the rear of a turbo engine, and a turbo engine improved by said method. According to the invention, the nozzle for the cold flow (9) is modified by a transverse expansion and a lengthening thereof such as to be able to increase the length of the acoustic damping coating (14) supported on the inside of said nozzle.

Abstract: The invention relates to a method for making an acoustic absorption panel in particular for the nacelle of an aircraft engine, the panel being of the type comprising a cellular core covered on one side with a so-called outer air-permissive skin and on the other side with a so-called inner perforated skin, the cellular core being formed by the edge-to-edge junction of a plurality of blocks with a cellular core (B1, B2). The method comprises the following steps: a) before the edge-to-edge junction of blocks with a cellular core (B1, B2), opening the cells (A1, A2) located on the edges of the blocks to be joined; and b) edge-to-edge dry joining the blocks (B1, B2) so that the open cells (A1, A2) engage into one another.