Abstract: According to an aspect, an ejector member includes an annular member; a vent arranged at the annular member, the vent having an inlet at a first surface of the annular member, the vent further having an outlet arranged radially inward from a second surface of the annular member; and a vane extending radially inward from the second surface of the annular member.

Abstract: A turbofan engine is provided. The turbofan engine includes a fan comprising a plurality of fan blades; a turbomachine operably coupled to the fan for driving the fan, the turbomachine comprising a compressor section, a combustion section, and a turbine section in serial flow order and together defining a core air flowpath; a nacelle surrounding and at least partially enclosing the fan; an inlet pre-swirl feature located upstream of the plurality of fan blades, the inlet pre-swirl feature attached to or integrated into the nacelle; and a means for directing incoming objects towards an outer portion of the turbofan engine in communication with the inlet pre-swirl feature.

Abstract: An apparatus of amplifying sound waves may include a metamaterial structure having a metamaterial inside thereof, an inlet through which air flows into the metamaterial structure, and a penetration portion formed to penetrate a portion of one side of the metamaterial structure, a membrane member coupled to the penetration portion, and a resonance member surrounding the membrane member and coupled to the metamaterial structure and including a space inside thereof and a discharge port fluidically communicating with an outside thereof and the internal space.

Abstract: The invention relating to a A damper for combustion oscillation damping for a gas turbine, includes a resonator cavity with a box or cylinder shape, a neck in flow communication with the resonator cavity and a combustion chamber. The length Lneck of the neck is equal or greater than a maximum distance lmax that a hot gas ingested from the combustion chamber reaches in the neck. The maximum distance lmax is determined according to the following equation: l max = ? t 1 t 2 ? U - p ^ ? ? ? U ? ? ? ? sin ? ( ? ? ? t ) ? ? d ? ? t . With the solution of the present invention, the damper used to damping combustion oscillation may prevent hot gas ingestion during normal operations by uniquely determining the dimensions of the neck connecting the resonator cavity and the combustion chamber.

Abstract: An aeroengine is provided with a splitter apparatus disposed in a section of an inlet duct. The splitter apparatus can be actuated from a stowed position to a deployed position to allow splitter(s) to selectively move from out of the inlet flow to a position extending into the inlet duct to divide the inlet flow into multiple passages.

Abstract: An aircraft control structure for drag management includes a nozzle structure configured to exhaust a swirling fluid stream. A plurality of swirl vanes are positioned within the nozzle structure, and an actuation subsystem is configured to cause the plurality of swirl vanes to move from a deployed state to a non-deployed state. In the non-deployed state, the plurality of swirl vanes are substantially flush with the inner surface of the nozzle structure. In the deployed state, the plurality of swirl vanes produce the swirling fluid stream.

Abstract: A damper arrangement (10) has a first Helmholtz damper (11) connected in series to a second Helmholtz damper (12). The resonance frequency of the first Helmholtz damper (11) and the resonance frequency of the second Helmholtz damper (12) are shifted from one another in an amount producing a synergic damping effect.

Abstract: In one embodiment, a system includes a variable geometry resonator configured to couple to a fluid path upstream from a combustor of a turbine engine. The variable geometry resonator is configured to dampen pressure oscillations in the fluid path and the combustor.

Abstract: A jet engine adapted for reducing far-field noise levels is disclosed. The jet engine has a plurality of flap assemblies that are disposed around a perimeter of an exhaust port of the jet engine. Each flap assembly is movable between a first position and a second position. The jet engine also includes a plurality of actuators respectively coupled to the plurality of flap assemblies. Each actuator is configured to selectively move the coupled flap assembly between the first and second positions. The jet engine also includes a controller that is coupled to each actuator. The controller is configured to cause at least one actuator to move the coupled flap assembly between the first and second positions at a determined frequency.

Abstract: A speaker with acoustic chamber is provided. The speaker includes a main body and an acoustic chamber fixed to the main body. The acoustic chamber can be converted between a collapsed state and an expanded state. The acoustic chamber is drawn to the expanded state to increase the volume of the acoustic chamber and is collapsed to the collapsed state to decrease the volume of the acoustic chamber. When the acoustic chamber is drawn to the expanded state, the quality of the sound output by the speaker is improved.

Abstract: A Tier 4 ready silencer that can accept both DOCs and DPFs to meet Tier 3 and can interface with an SCR system to meet Tier 4. The invention includes a silencer compartment with empty filter/catalyst banks in the shape of a V. DOCs and DPFs can be added and arranged in the V-shaped banks as needed. Various exhaust fins direct exhaust flow through the filters/catalysts. Multiple exhaust inlets to the device provide the most direct route possible from the engine outlets. A mixing tube and an SCR system can be added to the output port to comply with Tier 4.

Abstract: A ram intake unit mounted on a front portion of a frame structure of a motorcycle includes an acoustic material disposed along an inner wall of a ram air intake duct for absorbing induction noises, which duct forms an induction system through which an incoming wind can be introduced towards a motorcycle combustion engine, and a holder disposed inwardly of the acoustic material for securing the acoustic material to the ram air intake duct.

Abstract: In order to provide noise suppression, bumps or undulations are provided on a nozzle surface in order to vary the convergent-divergent ratio between that surface and an opposed nozzle surface. By such an approach, a circumferential variation in the shock cell pattern is created and the flow is deflected so as to enhance turbulent mixing thereby suppressing noise.

Abstract: The invention uses tubes for the reduction of radiated duct noise. The tubes may be used to attenuate narrow band noise by diverting a portion of the acoustic energy through the tubes back into the duct. Upon reintroducing the diverted flow out of phase with the primary flow, acoustic cancellation is achieved. The frequency at which this occurs is dependent on the difference in the path lengths through the tubes and the separation distance—the distance separating the inlet and outlet of the tube. This invention can be used over varying frequency ranges by using an arrangement of flexible, constant length tubes. The effective frequency range is tailored by varying the separation distance and also allows the varying the angular arrangement of the tubes for more effective attenuation of spinning modes having varying propagation angle.

Abstract: The invention uses tubes for the reduction of radiated duct noise. The tubes may be used to attenuate narrow band noise by diverting a portion of the acoustic energy through the tubes back into the duct. Upon reintroducing the diverted flow out of phase with the primary flow, acoustic cancellation is achieved. The frequency at which this occurs is dependent on the difference in the path lengths through the tubes and the separation distance—the distance separating the inlet and outlet of the tube. This invention can be used over varying frequency ranges by using an arrangement of flexible, constant length tubes. The effective frequency range is tailored by varying the separation distance and also allows the varying the angular arrangement of the tubes for more effective attenuation of spinning modes having varying propagation angle.

Abstract: An acoustic filter is provided with a single flow chamber for exposure of a flexible rubber layer to liquid undergoing flow through the flow chamber with noise producing acoustic energy therein. The flexible rubber layer is supported on a cylindrical drum with slanted holes therein through which the exposure to the liquid in the flow chamber is effected. An axially sectioned drum with dimensionally different diameters, radial thicknesses and slanted holes therein is positioned over the rubber layer within an outer casing to establish a plurality of gas-filled cavities of different axial lengths and separated from each other along the axial length of the liquid flow chamber which is connected at its opposite axial ends by pipe sections to a piping system from which the liquid within the flow chamber is derived.

Abstract: A serviceable muffler (20) has an end plate (34) releasably clamped (36) to an open end (30) of a muffler body (26) and permitting access to an internal catalytic or filter element (28) for removal and replacement. An apertured flange (44) has an outer border with flared rounded portion (46) complemental to flared rounded portions (40 and 42) of each of the end plate (34) and the open end (30) of the body (26), and having an inner border defined by an aperture (48) through which the element (28) is removed and replaced. Servicing and manufacturing methods are provided.

Abstract: An assembly useful in reducing aircraft engine noise such as turbofan engine noise (730) comprises: (i) at least one tube “H-Q” having an inlet end (738), an outlet end (740) and a central tube portion therebetween; and (ii) at least one actuator operatively interconnected to at least one tube, wherein the actuator is capable of causing dynamic response by the tube. The assembly of this invention may be used in a method for reducing noise, the method comprising: (a) providing means for generating non-uniform noise energy about an inner surface and within a disclosure having at least an inlet; (b) providing an assembly for reducing noise comprising; (i) at least one having an inlet end, an outlet end and a central tube portion therebetween, and (ii) at least one actuator operatively interconnected to at least one tube, wherein the actuator is capable of causing dynamic response by the tube; and (c) directing at least a portion of the non-uniform noise into the assembly.

Abstract: The tunable resonator is coupled to the engine speed control such that the resonator is set to a different frequency range when the engine speed is changed. The frequency range is changed by opening and closing necks and/or changing the effective volume of the resonator.

Abstract: A device for noise structuring in a motor vehicle has a plurality of gas-carrying lines connected to an internal combustion engine. At least two of the gas-carrying lines are acoustically linked together by at least one connection.

Abstract: An exhaust processor comprises a Helmholtz resonance chamber with a variable tuning throat. The tuning frequency of the exhaust processor changes as the outlet opening from the variable tuning throat into the Helmholtz resonance chamber changes.

Abstract: A muffler arrangement includes an exhaust-gas muffler, which is subdivided into an inlet space and an outlet space. An exhaust-gas stub of an internal combustion engine opens into the inlet space. Exhaust gas is conducted from the outlet space into an air channel via an exhaust-gas outlet. The air channel is formed between the housing of the exhaust-gas muffler and an outer cover and extends along a side of the exhaust-gas muffler. A cooling-air component flow is branched from a cooling-air flow of a cooling-air blower and enters at a first end of the air channel. The cooling-air component flow exits again at the second end of the air channel.

Abstract: An exhaust processor has an exhaust tube and a cover mounted for rotation at least partially around the exhaust tube to adjust the tuning frequency of the exhaust processor. A method of operating the exhaust processor is also disclosed.

Abstract: In order to reduce noise effectively and to provide a light-weight noise reducing apparatus and an exhaust nozzle for a jet engine, a mixer for mixing an exhaust gas and an external air is disposed behind an engine, a flow channel for accelerating an exhaust gas toward a mixer and a flow channel for introducing an external air to a mixer are formed by a flow channel forming section in a noise reducing mode.

Abstract: An elliptical speaker system is provided for in-wall/in-ceiling mounting. The speaker system comprises an elliptical speaker frame or bracket defining a speaker front plane having a generally arcuate inner surface. First and second speaker components are mounted within the speaker frame, on opposing sides of the speaker inner surface. At least one of the speaker components may be translatable within the speaker frame.

Abstract: An exhaust processor comprises a Helmholtz resonance chamber with a variable tuning throat. The tuning frequency of the exhaust processor changes as the outlet opening from the variable tuning throat into the Helmholtz resonance chamber changes.

Abstract: A sound level adjustable muffler has a pop-up mechanism working in parallel pairs used for lifting the tabletop part of a piece of furniture has a pair of cantilever arms joined together by an upper oblong member and a lower oblong member, both said upper oblong member and lower oblong member being parallel relative to each other and each being rotationally attached to opposite ends of said pair of cantilever arms.

Abstract: An apparatus for damping acoustic vibrations in a combustor as well as a corresponding combustor arrangement with the apparatus. The apparatus includes a Helmholtz resonator (4) that can be connected via a connecting channel (2) with a combustor (1). The Helmholtz resonator (4) contains a hollow body (6) the volume of which can be changed by adding or draining a fluid via a supply line (5), or is located adjacent to such a hollow body in such a way that the resonance volume (3) of the Helmholtz resonator (4) is changed when the volume of the hollow body (6) is changed. This apparatus makes it possible to adjust the resonance frequency of a Helmholtz resonator arranged inside a pressure container in accordance with the respective current operating point of the combustor to be damped, without having to pass movable components through the pressure container.

Abstract: A silencer is disclosed with a bypass resonator (4; 9, 12) connected by at least one tubular connection (3a, 3b; 7, 8; 13) to a sound-transmitting channel (1). The tubular connection (3a, 3b) can have various lengths (La, Lb), tubular connections (7, 8) of different thicknesses can be connected, or the volume (V1, V2, Vn) of the bypass resonator (13) can be variable.

Abstract: A apparatus and method for augmenting the thrust of a jet engine while reducing the noise generated thereby, including extending the thrust reverser sleeve, exposing the cascades while retaining the thrust reverser doors or buckets in their stowed position.

Abstract: A sound adjustable tail pipe structure includes an adjuster secured in a rear section of a tail pipe which defines a first oblong slot. The adjuster includes a tube having a first end provided with a first positioning base and a second end provided with a second positioning base, and an adjusting base rotatably mounted in the second positioning base. The first positioning base defines a first through hole connecting to the tube and has a wall defining a plurality of first guide holes. The second positioning base defines a second through hole connecting to the tube and has a wall defining a plurality of second guide holes, and a peripheral wall defining a second oblong slot. The adjusting base defines a third through hole connecting to the second through hole and has a wall defining a plurality of third guide holes aligning with each of the second guide holes, and a peripheral wall defining a screw hole.

Abstract: A method of reducing noise from a jet engine at a distance D from the engine comprising the step of up-shifting frequencies of noise from the jet engine to higher frequencies to cause increased noise fall-off in the distance D. Where the jet engine has an exhaust nozzle for exhaust gases carrying the noise of minimum cross-sectional area A, the method comprises, disposing a frequency shifting plate containing a plurality of small openings therethrough of total cross-sectional area A across the exhaust nozzle and passing all exhaust gases from the jet engine through the frequency shifting plate. Each of the plurality of small openings has an individual cross-sectional area which up-shifts frequencies of noise from the jet engine passing therethrough to higher frequencies. Various embodiments of apparatus to perform the method are disclosed.

Abstract: A noise suppression system for a jet engine of an aircraft having a device for blocking a flow of exhaust gases down the exhaust nozzle of the engine, and a device for separating the exhaust gases into a plurality of exhaust streams spaced a predetermined distance apart and having a smaller cross-sectional area than that of the original flow of exhaust gases. The separating device also directs the exhaust streams into the ambient air from points outside the periphery of a nacelle covering the engine. The aforementioned predetermined distance separating the exhaust streams, and the cross-sectional area of the exhaust streams, are chosen so that engine noise is shifted to a higher frequency spectrum than that of the original flow of exhaust gases, and then substantially dissipated within a short distance of the aircraft.

Abstract: A gas turbine engine flow mixer includes at least one chute having first and second spaced apart sidewalls joined together at a leading edge, with the sidewalls having first and second trailing edges defining therebetween a chute outlet. The first trailing edge is spaced longitudinally downstream from the second trailing edge for defining a septum in the first sidewall extending downstream from the second trailing edge. The septum includes a plurality of noise attenuating apertures.

Abstract: A jet engine noise suppressor particularly adapted for supersonic aircraft. The nozzle (10) has an internal wall surface (70) around a generally centrally positioned body (50) and an annular area (62) extending between the wall and the body. In this area there are separate gas and air flow ducts (64, 66) having entrance ends (82, 80) and exit ends (76, 78), the entrance ends of the gas ducts extending annularly around the body (50) to receive gas exhaust from the engine and the air ducts have entrance ends annularly outwardly of the gas ducts along the wall (70). There are openings (26) in a wall (14) upstream of the ducts to supply ambient air to the entrance ends (80) of the air ducts. There are doors (20) and actuators (24) operable to open and close the openings (26).

Abstract: Apparatus for internally mixing fan exhaust with primary exhaust forward of the nozzle exit plane of a turbofan engine having an outer engine cowling, a splitter wall structure and a tail plug disposed in mid engine upstream of the nozzle exit plane is provided by a plurality of struts disposed radially between the engine tail plug and the outer engine cowling upstream of the nozzle exit plane and a plurality of vortex generating means disposed on the struts for generating vorticies across the entire engine exhaust area.