Abstract: An object is to provide a silencing system that can achieve both high ventilation performance and high soundproof performance, can silence a plurality of pieces of resonant sound, and has high general-purpose properties since the silencing system does not need to be designed according to a tubular member.

Abstract: In a sound absorption panel formed by stacking a plate perforated with a hole having a hole size smaller than a fiber length such as expanded metal, a honeycomb material, and felt-like fiber between the perforated plate and the honeycomb material, and joining the perforated plate, the felt-like fiber, and the honeycomb material to each other with an adhesive, the adhesive applied to the perforated plate is permeated into a surface of the felt-like fiber exposed from the hole to fix the fiber on the surface.

Abstract: A suppressor having a body and a first connector half coupled to the body, wherein the first connector half includes a first component that includes at least one channel and a first surface; and wherein the body provides a second surface, wherein a gap between the first surface and the second surface defines at least one track; wherein the gun includes a second connector half comprising at least one protrusion, wherein the protrusion and channel have corresponding shapes that allow the protrusion to be inserted through the channel and into alignment with the track, wherein the first component may be rotated with respect to the protrusion and the body to bring the protrusion out of alignment with the channel so that the first and second surfaces clamp the protrusion to thereby secure the first connector half and second connector half with respect to each other.

Abstract: A sound absorber includes at least one cavity and at least one mouth to communicate the at least one cavity with an outside of the sound absorber. The at least one cavity includes a top surface, a bottom surface, and a side wall. The top surface includes the mouth. The bottom surface opposes the top surface. The side wall is extended to connect the top surface with the bottom surface. At least one of the top surface and the bottom surface is inclined with respect to the side wall.

Abstract: The present application provides a sound adsorbing material, including a microporous material and an adsorbate gas adsorbed in the microporous material. The microporous material includes a zeolite molecular sieve, and the zeolite molecular sieve has a framework and extra-framework cations. An adsorption capacity of the adsorbolite molecular sieve to the adsorbate gas is greater than an adsorption capacity of the adsorbolite molecular sieve to air. The present disclosure further provides a speaker box adopting the sound adsorbing material. Compared with the related art, the sound adsorbing material provided by the present disclosure has good application effects, and the speaker box using the sound adsorbing material has a better low frequency acoustic performance.

Abstract: An apparatus comprises a circuitry and an acoustic-capture tile having a surface that is to face an acoustic source that is to emit a first acoustic wave having a first frequency and a second acoustic wave having a second frequency. The acoustic-capture tile comprises a first acoustic-capture subtile electrically coupled to the circuitry, the first acoustic-capture subtile to resonate at the first frequency, wherein the first acoustic-capture subtile is to capture the first acoustic wave and to convert the first acoustic wave into a first electric current in response to resonance at the first frequency. The acoustic-capture tile also comprises a second acoustic-capture subtile electrically coupled to the circuitry, the second acoustic-capture subtile to resonate at the second frequency, wherein the second acoustic-capture subtile is to capture the second acoustic wave and to convert the second acoustic wave into a second electric current in response to resonance at the second frequency.

Abstract: A panel for machinery enclosure, particularly for turbomachine enclosures. More specifically, a multilayered panel including several different layers each performing a specific function. In particular, the multilayered panel is capable to provide high levels of jet fire and fire/blast protection together with high performances in term of noise abatement with a lighter structure with respect to the panels of the prior art.

Abstract: An aerospace component, for example, used in a gas turbine engine, includes the following structurally-integrated layers: a metallic layer and a composite layer having reinforcing fibers embedded in a matrix material. The aerospace component can also include an insulating layer disposed between the metallic layer and the composite layer where the insulating layer has a thermal conductivity that is lower than a thermal conductivity of the composite layer.

Abstract: A reciprocating piston air compressor includes a programmable logic controller, a tank, a motor, a pump, a variable speed drive, a head unloader and a cooling system. The programmable logic controller and/or variable speed drive are utilized to monitor the operating state of the air compressor and to control various operational variables, such as motor and pump speed. The air compressor can utilize the variable speed drive to operate a three phase motor on single-phase power.

Abstract: A sound absorbing panel for managing acoustic environments with desired durability, stiffness and advantageous characteristics for self-supporting sound-absorbing panels intended to be attached to indoor walls and ceilings of buildings. The sound absorbing panel comprising a height, a width, a length and a cover. The sound absorbing panel comprising materials characterized by an inner core comprising a core density, a core binder and a thickness. The core density is between two and a half and four and a half pounds per cubic-foot. The core binder is between one and three-fourths and two and three fourths percent. The thickness comprises a thickness between 35-45 mm. The cover comprises a cover weight. The cover weight is between one quarter and one half ounces per foot.

Abstract: Described herein is an acoustic ceiling panel comprising: a first air-permeable body comprising a first major surface opposite a second major surface and a side surface extending between the first and second major surfaces, the first body having an NRC value of at least 0.5 as measured between the first and second major surfaces of the first body; and an attenuation coating applied to the second major surface of the body and the side surface of the body, whereby the attenuation coating seals at least a portion of the second major surface and the side surface of the body.

Abstract: Sound attenuation panel for aircraft having a combination of acoustic attenuation properties. The acoustic panel includes an acoustic structure having a cellular structure and a resistive skin and a backing skin, the acoustic panel also including at least one auxiliary acoustic device with cavities that is configured to produce additional acoustic absorption, the auxiliary acoustic device with cavities being attached to the acoustic structure and including adjacent chambers or cavities separated by shared walls, each of the chambers or cavities having perforations and being adapted to produce acoustic absorption. The combination of the acoustic structure and the auxiliary acoustic device with cavities enables combination of the acoustic absorption properties of these two types of element and an increased range of frequencies of the noise that can be attenuated by the acoustic panel without increasing its overall size.

Abstract: Apparatuses and methods for tuning a muffler. An apparatus comprises a housing for a muffler, a first inlet pipe, and a second inlet pipe. The housing includes a coupling chamber. The first inlet pipe has a first set of physical features and carries exhaust to the coupling chamber. The second inlet pipe has a second set of physical features and carries the exhaust to the coupling chamber. The first set of physical features varies from the second set of physical features with respect to at least one physical feature such that a first sound waveform passing through the first inlet pipe and a second sound waveform passing through the second inlet pipe are uniquely tuned to thereby tune an overall sound waveform emitted by the muffler.

Abstract: A sound absorber for an engine of an aircraft, the sound absorber comprising: a base body having a bottom plate, a wall enclosing the bottom plate and an opening enabling entry of air into the base body; and a porous tongue having a fixed end connected to the wall and a free end; wherein the tongue is porous.

Abstract: Acoustic honeycomb structures that include cells in which a friction-locking insertion process is used to locate acoustic barriers within honeycomb cells to provide multiple degree of freedom (MDOF) acoustic liners having a variety of acoustic resonator depths. Solid polymer films are formed into acoustic barrier caps. The acoustic barrier caps are friction-locked and bonded to cell walls at one or more cell depths to form acoustically reflective hard walls that form effective bottom ends for acoustic resonators.

Abstract: An exhaust muffler for an internal combustion engine includes a housing. A plurality of partitions are disposed within the housing, defining a plurality of chambers. An inlet pipe and an outlet pipe are also disposed within the housing and both the inlet and outlet pipes include a perforated region. The perforated region permits fluid communication between the inlet pipe, outlet pipe and the plurality of chambers. To attenuate engine noise, the perforated regions of the inlet and outlet pipes are positioned at opposite ends of the housing, forcing the exhaust gas to pass through each of the plurality of partitions and chambers, thereby damping the sound waves with minimum effect on engine back pressure levels. Alternatively, the perforated regions of the inlet and outlet pipes may be aligned in a cross-flow chamber.

Abstract: An acoustic liner may include an acoustic core having an array of resonant cells, and an acoustic screen disposed across the array of resonant cells. The resonant cells include a plurality of cell walls and a resonant space defined by the plurality of cell walls. The acoustic core may include a folded acoustic core. Additionally, or in the alternative, at least some of the resonant cells may include an oblique polyhedral cellular structure and/or a multitude of sound-attenuating protuberances. The acoustic screen may include a reticulate membrane and a support lattice.

Abstract: The present invention discloses a sound-absorbing piece and a preparation method thereof. The preparation method of the sound-absorbing piece comprises: preparing perforated sound-absorbing cotton matched with a preset cavity in shape; mixing sound-absorbing material powder with a solvent and a template agent to prepare a sound-absorbing slurry; impregnating the perforated sound-absorbing cotton with the sound-absorbing slurry for a preset period; and drying the perforated sound-absorbing cotton impregnated with the sound-absorbing slurry to remove a liquid in the perforated sound-absorbing cotton.

Abstract: A sound absorbing filter for a dust collector system is attached downstream of the system air blower and ahead of the cylindrical HEPA filter cartridge. The sound filter is formed of a cylindrical barrel or shell, favorably steel, another metal, plastics, or composite with end-caps bonded on. The cylindrical shell interior is lined with plural annular layers of sound absorbing materials. The sound absorbing elements are retained with two or more thin retainer plates The lining can comprise a radial outer layer of compressed fiber batting, and a radial inner layer of convoluted acoustic polyurethane foam 1 to 2 inches thick. The foam lining protects the fiberglass from the air flow reducing fiber shedding, and also absorbs higher frequencies, with the fiberglass being more absorptive of lower frequencies.

Abstract: The disclosure relates to acoustic panels and methods for preparing them. The disclosure relates more particularly to panels having a porous facing and to methods for making such panels. One aspect of the disclosure is an acoustic panel comprising a base structure. The base structure has one or more edges, an outward major surface having a total area, and an inward major surface opposing the outward major surface. The base structure has a noise reduction coefficient (NRC) of at least about 0.3. The panel includes a coating layer directly disposed on the outward major surface of the base structure, the coating layer being formed of an open-cell foam. The coating layer has an exterior major surface opposing the outward major surface of the base structure. The coating layer is substantially scattering for light in the wavelength range of 380 nm to 780 nm, and has an absorption coefficient of less than 0.5 for acoustic frequencies in the range of 100 Hz to 10,000 Hz.