Abstract: An array of discrete sound absorbers (20a, 20b) is attached to an inner surface (122) of an annular tread portion (12) of a pneumatic tire (10) or an annular rim surface (34) of a wheel rim (30) to reduce tire cavity noise. Each sound absorber (20a, 20b) includes a flexible sheet-like base material (54), a sheet-like screen material (52), and a sound absorbing material (56) disposed in a closed space formed by the sheet-like base material (54) and the sheet-like screen material (52).

Abstract: A rotary acoustic horn. The rotary acoustic horn includes a shaft having an axial input end and an axial output end; and at least one welding portion; wherein the welding portion comprises an outer weld face that expands and contracts with the application of acoustic energy; wherein the welding portion comprises a first opposing end portion and a second opposing end portion; wherein the welding portion comprises through holes extending substantially along an axial direction of the welding portion from the first opposing end portion to the second opposing end portion; and wherein the through holes are located between the weld face and the shaft.

Abstract: An assembly includes an enclosure including first and second regions spaced apart along a first direction, and a plurality of spaced apart acoustic baffles arranged along a second direction different from the first direction and disposed in the enclosure between the first and second regions. The plurality of spaced apart acoustic baffles includes adjacent first and second acoustic baffles. Each of the first and second acoustic baffles include an acoustically absorptive layer disposed on a sheet having a specific airflow resistance greater than 200 MKS Rayl. The first and second acoustic baffles define a channel therebetween. At least a portion of the channel extends along a longitudinal direction making an oblique angle with the first direction.

Abstract: Provided are conduits for air flow that are capable of reducing noise and related methods. The provided conduits include a first section that is tubular and substantially non-perforated and a second section with at least a portion having a multiplicity of microperforations that provide an average flow resistance of from 50 MKS Rayls to 8000 MKS Rayls therethrough. The second section is either (a) tubular and connected in series with the first section, with an outer surface of the second section being in fluid communication with an outer surface of the conduit, or (b) disposed within the first section.

Abstract: A multilayer damping material for damping a vibrating surface comprising: at least one constraining layer; at least one dissipating layer; and at least one kinetic spacer layer comprising multiple spacer elements. The kinetic spacer layer is arranged between the constraining layer and the vibrating surface, when used for damping the vibrating surface. Each spacer element has opposite ends. At least one end of each of the multiple spacer elements is embedded in, bonded to, in contact with, or in close proximity to the dissipating layer, such that energy is dissipated within the multilayer damping material, through movement of the at least one end of each of the multiple spacer elements.

Abstract: Multilayer damping material for damping a vibrating surface (10) including: at least one constraining layer (4); at least one dissipating layer (1, 3); at least one kinetic spacer layer (2) including multiple spacer elements (2b), the kinetic spacer layer being arranged between the constraining layer and the vibrating surface, when used for damping the vibrating surface, wherein each spacer element has opposite ends, at least one end of each of the multiple spacer elements is embedded in, bonded to, in contact with or in close proximity to the dissipating layer, such that energy is dissipated within the multilayer damping material, through movement of the at least one end of each of the multiple spacer elements; absorbing material as at least one additional layer (12) or within at least one of the above layers.

Abstract: Provided are conduits for air flow that are capable of reducing noise and related methods. The provided conduits include a first section that is tubular and substantially non-perforated and a second section with at least a portion having a multiplicity of microperforations that provide an average flow resistance of from 50 MKS Rayls to 8000 MKS Rayls therethrough. The second section is either (a) tubular and connected in series with the first section, with an outer surface of the second section being in fluid communication with an outer surface of the conduit, or (b) disposed within the first section.

Abstract: Articles and methods of making and using the articles are provided. The articles include inorganic agglomerates having an average dimension in a range from about 50 microns to about 2 mm. The porous agglomerates each include a network of carbon or silica, and metal oxide particles embedded in the network. Some agglomerates are capable of lowering a resonant frequency of an acoustic device when the resonant frequency is in a range from about 50 Hz to about 1500 Hz.

Abstract: Provided acoustic devices include an external housing defining an expansion chamber and a wall extending through and partitioning the expansion chamber into a central chamber and a peripheral chamber adjacent the central chamber, wherein an inlet and outlet communicate with the central chamber, and wherein the wall includes a plurality of apertures formed therethrough to allow air movement to and from the central and expansion chambers, the plurality of apertures sized to provide an average flow resistance ranging from 100 MKS Rayls to 5000 MKS Rayls. The acoustic devices advantageously show significant sound attenuation while streamlining air flow to reduce pressure drop across the expansion chamber.

Abstract: Panels comprising first and second layers and a core disposed there between, wherein the core has a plurality of walls providing a series of connected cells, wherein some of the cell walls have openings providing fluid communication between a series of at least 3 cells, and wherein the opening in a cell wall has an area that is at least 50 percent of the area of a side of that cell wall. Exemplary embodiments of panels described herein can be formed articles such as panels, walls, or other parts with curved surfaces. In one exemplary method, panels are shaped via thermoforming. In another exemplary method, panels are shaped via insert molding to provide the article. In another exemplary method, panels are shaped via compression molding to provide the article. The panels are useful for absorbing sound in a designed frequency range.

Abstract: Articles and methods of making and using the articles are provided. The articles include inorganic agglomerates having an average dimension in a range from about 50 microns to about 2 mm. The porous agglomerates each include a network of carbon or silica, and metal oxide particles embedded in the network. Some agglomerates are capable of lowering a resonant frequency of an acoustic device when the resonant frequency is in a range from about 50 Hz to about 1500 Hz.

Abstract: Sound insulation constructions, multilayer constructions for acoustically insulating a source of sound from a receiver that include one or more sound insulation constructions, structures comprising one or more sound insulation constructions and/or multilayer constructions, and a method for acoustically insulating a source of sound from a receiver. In some embodiments, the sound insulation construction includes a first layer and a second layer. The first layer can include a bonded fiber nonwoven web exhibiting a work of compression of at least about 0.7 kJ/m3 and an airflow resistance of no greater than 10,000 Rayls/m. The second layer can exhibit an airflow resistance of greater than 10,000 Rayls/m. In some embodiments, the method includes coupling the first layer to a surface of a vehicle to attenuate sound in at least a portion of the vehicle.

Abstract: A multilayer damping material for damping a vibrating surface comprising: at least one constraining layer; at least one dissipating layer; and at least one kinetic spacer layer comprising multiple spacer elements. The kinetic spacer layer is arranged between the constraining layer and the vibrating surface, when used for damping the vibrating surface. Each spacer element has opposite ends. At least one end of each of the multiple spacer elements is embedded in, bonded to, in contact with, or in close proximity to the dissipating layer, such that energy is dissipated within the multilayer damping material, through movement of the at least one end of each of the multiple spacer elements.

Abstract: Sound insulation constructions, multilayer constructions for acoustically insulating a source of sound from a receiver that include one or more sound insulation constructions, structures comprising one or more sound insulation constructions and/or multilayer constructions, and a method for acoustically insulating a source of sound from a receiver. In some embodiments, the sound insulation construction includes a first layer and a second layer. The first layer can include a bonded fiber nonwoven web exhibiting a work of compression of at least about 0.7 kJ/m3 and an airflow resistance of no greater than 10,000 Rayls/m. The second layer can exhibit an airflow resistance of greater than 10,000 Rayls/m. In some embodiments, the method includes coupling the first layer to a surface of a vehicle to attenuate sound in at least a portion of the vehicle.

Abstract: Provided acoustic devices include an external housing defining an expansion chamber and a wall extending through and partitioning the expansion chamber into a central chamber and a peripheral chamber adjacent the central chamber, wherein an inlet and outlet communicate with the central chamber, and wherein the wall includes a plurality of apertures formed therethrough to allow air movement to and from the central and expansion chambers, the plurality of apertures sized to provide an average flow resistance ranging from 100 MKS Rayls to 5000 MKS Rayls. The acoustic devices advantageously show significant sound attenuation while streamlining air flow to reduce pressure drop across the expansion chamber.

Abstract: The invention is a mounting system for a vibrational element. The vibrational element has a longitudinal axis, an outer surface and an axial displacement node. The mounting system includes an isolation member which has an isolation surface, an isolating body, and an engaging portion. The engaging portion is immovably secured to the isolation member and extends radially inward from the isolation body at a point radially opposite the isolation surface. The engaging portion is disposed so as to engage the outer surface of the vibrational element. Radial displacements of the vibration element are substantially decoupled from the isolation surface through the engaging portion.

Abstract: An acoustic system for applying vibratory energy including a horn connected to an ultrasonic energy source. The horn defines an overall length and wavelength, and at least a leading section thereof is comprised of a ceramic material. The leading section has a length of at least ? the horn wavelength. In one preferred embodiment, an entirety of the horn is a ceramic material, and is mounted to a separate component, such as a waveguide, via an interference fit. Regardless, by utilizing a ceramic material for at least a significant portion of the horn, the ultrasonic system of the present invention facilitates long-term operation in extreme environments such as high temperature and/or corrosive fluid mediums. The present invention is useful for fabrication of metal matrix composite wires.

Abstract: An acoustic system for applying vibratory energy including a horn connected to an ultrasonic energy source. The horn defines an overall length and wavelength, and at least a leading section thereof is comprised of a ceramic material. The leading section has a length of at least ? the horn wavelength. In one preferred embodiment, an entirety of the horn is a ceramic material, and is mounted to a separate component, such as a waveguide, via an interference fit. Regardless, by utilizing a ceramic material for at least a significant portion of the horn, the ultrasonic system of the present invention facilitates long-term operation in extreme environments such as high temperature and/or corrosive fluid mediums. The present invention is useful for fabrication of metal matrix composite wires.

Abstract: An acoustic system for applying vibratory energy including a horn connected to an ultrasonic energy source. The horn defines an overall length and wavelength, and at least a leading section thereof is comprised of a ceramic material. The leading section has a length of at least ? the horn wavelength. In one preferred embodiment, an entirety of the horn is a ceramic material, and is mounted to a separate component, such as a waveguide, via an interference fit. Regardless, by utilizing a ceramic material for at least a significant portion of the horn, the ultrasonic system of the present invention facilitates long-term operation in extreme environments such as high temperature and/or corrosive fluid mediums. The present invention is useful for fabrication of metal matrix composite wires.

Abstract: A resonant, nodal mount suitable for linear horns.