Abstract: A system and method for controlling noise generated from a wind turbine is disclosed. The method includes selectively adjusting the angle of pitch of the blade in response to an amount of noise generated being above a predetermined amount and maintaining the amount of noise generated at or below the predetermined amount of noise.

Abstract: An exhaust-noise attenuation muffler includes two half-shells, each including an inner shell and an outer shell which are made through deep drawing of a sheet metal blank which can have a thickness between 0.3 mm and 0.5 m. The inner shell or the outer shell is provided with an embossment. After placing the inner shells in corresponding ones of the outer shells to form half-shells, two complementing half-shells are joined together.

Abstract: A method and apparatus for the reduction of sound travelling in a wave-guide in the air above the ground is presented, comprising the provision below the ground of at least a top layer which, at the interface of the top layer and air, has an acoustic impedance which substantially matches the acoustic impedance of the air. Also a cylindrical structure with holes can be used. The method and apparatus may be used for the reduction of aircraft sounds, especially in the range of 15 Hz to 40 Hz, during the first part of take-off, wherein said layer(s) below the ground are provided in a range starting at a lateral side of the runway and extending until at least 100 meters, preferably until at least 300 meters and more preferably until at least 500 meters, from the runway.

Abstract: This noise attenuator for a hydraulic fluid pipe is made of a material porous to the fluid intended to flow through the noise attenuator. More specifically, the material is a synthetic material. As a preference, the synthetic material is porous polytetrafluoroethylene.

Abstract: The present invention relates to a photovoltaic soundproof wall having a plurality of soundproof members each formed by surrounding the edge portions of two transparent sheets with a main frame and a plurality of posts adapted to mount the plurality of soundproof members therebetween, the photovoltaic soundproof wall including: a subframe disposed inside the main frame; a motor disposed inside the subframe for rotating a drive shaft rotatably mounted inside the subframe; a power transmission unit adapted to transmit the rotary force of the motor; a plurality of slats spaced apart from each other vertically between the two transparent sheets in such a manner as to be moved collectively by the power transmitted from the power transmission unit; and a plurality of solar cells attached to the top surface of each of the plurality of slats.

Abstract: A region of air is manipulated to reflect, absorb, or redirect sound energy to prevent the sound energy from reaching a listener separated from the sound source by the region of air. The region of air may be manipulated by directing ultrasonic sound waves with a sound pressure level of at least 140 decibels at the region of air.

Abstract: An exhaust silencer of a combustion engine, comprising a housing (1) that is to be connected to an exhaust pipe, through which housing the exhaust gases are arranged to be conducted and which comprises a reactive part (2) and an absorbing part (3) in the flow direction of the exhaust gases. The reactive part (2) is mainly hollow and comprises, at the inlet thereof, a first exhaust pipe (5) for feeding the exhaust gases to the reactive part (2) and, at its outlet, a second exhaust pipe (6) for directing the exhaust gases from the reactive part (2) to the absorbing part (3), both exhaust pipes (5, 6) being arranged so as to essentially extend inside the reactive part (2) of the housing. The absorbing part (3) comprises an absorbing filling element (7), which essentially fills the absorbing part (3) of the housing and, at the inlet of the absorbing part (3), is shaped so as to direct the exhaust gases to the space (8) between the filling element (7) and the inner lining of the housing (1).

Abstract: An exhaust system for an internal combustion engine, having a first exhaust tract assigned to a first group of cylinders of the internal combustion engine, and having a second exhaust tract assigned to a second group of cylinders of the internal combustion engine, each exhaust tract comprising an exhaust gas purification device, a first silencer arranged on the outlet side of the respective exhaust gas purification device, and a second silencer arranged on the outlet side of the respective first silencer. Each exhaust tract includes a bypass line, it being possible for exhaust gas to be diverted via each bypass line, starting from the respective first silencer, bypassing the second silencers, and the bypass lines and hence the first silencers of both exhaust tracts being connected to one another by a mixing line.

Abstract: The present invention provides an assembly of a tire and a rim, which assembly has on the tire inner cavity side thereof a sound absorbing member capable of effectively suppressing cavity resonance and reducing road noise, while suppressing increase in weight of the tire and increase in volume of the sound absorbing member. In this assembly of a tire and a rim, the sound absorbing member is mounted on the inner cavity side of the tire as a sound absorbing layer for suppressing cavity resonance inside the tire. The sound absorbing member is unwoven cloth made of plural fibers, and the average distance d between fibers constituting the unwoven cloth is within the range of 0.50? to 4.00?.

Abstract: An acoustically resistive protective cover assembly for an opening in a casing is provided, the casing separates an enclosed space from the ambient space and has an exposed face oriented toward the ambient space and an internal face oriented toward the internal space. The cover assembly comprises an acoustically resistive porous material disposed upon the exposed face of the case and an acoustically resistive water repellant material disposed upon the internal face of the case.

Abstract: A substrate such as a heat shield for a vehicle is provided with a unitary compressed wire mesh bushing or isolator formed in place though a bore in the substrate. The bushing is formed by supporting an uncompressed or partially compressed wire mesh sleeve, optionally including a grommet or spacer, on a mandrel positioned within the bore; the mandrel is surrounded on either side of the bore by outer sleeves forming a molding cavity on each side of the substrate, and a slidable tamp is disposed in each outer sleeve and moved towards each other to compress the mesh within the bore and provide the unitary bushing.

Abstract: An engine and a generator driven by the engine are resiliently supported on a frame. A duct member is integrally attached to the engine and the generator to define a continuous cooling-air passage between the duct member and outer peripheral surfaces of the engine and the generator. A cooling fan is disposed on an inlet side of the cooling-air passage. A silencing plate is integrally attached to the duct member and faces an inlet of the cooling-air passage with a ventilation gap defined therebetween. The silencing plate has an area opposing the inlet that is larger than an opening area of the inlet.

Abstract: The invention relates to a foam part (1), in particular for suspended arrangement in a room, for example for use as a sound absorber (2), with an acoustic region of the foam part which has an outer contour being illuminated by a lighting element (11), further with the lighting element (11) being mounted on the foam part (1) and being disposed within the outer contour of the foam part (1). In particular, the invention also relates to a foam part (1) which is fixed, as a sound absorber (2), in a suspended manner to a room ceiling (3) or room wall, a lighting element (11) which is mounted on the sound absorber (2) and illuminates a subregion of the foam part (1), being provided in said foam part.

Abstract: A protective holder for the iPhone®, iPod Touch™, electronic books, electronic tablet computers and other portable devices having a frontal LCD, OLED, touch screen, or other display that employs a form-fitting backplate with corner frames for cradling the device while leaving the entire frontal aspect unobstructed is disclosed. The holder may include a series of contoured side grippers on each side of the backplate for clamping the device in place without obstructing the LCD screen (or access to it for cleaning or otherwise). The holder may include a fully-adjustable kickstand for upright hands-free viewing of the device at several landscape and portrait angles and the holder may also include a built-in moveable directional sound reflector and noise shield improves audio performance, and a detachable belt clip allows belt wearing. The holder has an extreme slimline folded profile to facilitate pocket insertion, minimize bulk and create an eye-catching aesthetic.

Abstract: An acoustical vibration dampening system for a rotatable blade comprises at least one section of a rotatable blade and a layer of acoustic damping material coupled to a portion of the at least one section of a rotatable blade. A fan blade comprises a first structural section of a fan blade, a second structural section of the fan blade, and a layer of acoustic damping material provided between the first structural section and the second structural section of the fan blade. A method of making a fan blade with acoustic damping comprises forming at least two sections of a fan blade, and disposing an acoustical vibration dampener between the at least two sections of the fan blade.

Abstract: An improved panel section for use in a sound barrier is disclosed and is of the type: having a cementitious body; for use with at least two vertically-extending, ground-mounted I-beam columns, each having two parallel flanges and a transverse web extending therebetween and being positioned with its web substantially parallel to the web of adjacent columns and substantially normal to a line defined by said columns; and disposed, in use, in respective vertically-stacked groupings to form one or more wall panels interleaved between adjacent pairs of columns, each panel having a pair of end edges disposed, one each, in mechanically-engaged relation, between the flanges of a respective pair of adjacent columns. The improvement comprises: the body having defined therethrough an opening; and a glazing element secured to said body to occlude said opening and impede sound passage therethrough. A sound barrier constructed from the improved panel section is also disclosed.

Abstract: An air filter system for an internal combustion engine of a vehicle can have an indicator for signaling restricted flow of air through a replaceable air filter member mounted to a filter assembly. At least one sidewall can be associated with the replaceable air filter member to be positioned with an air stream passing through the air filter member. A resettable air filter status indicator can provide a visually perceivable signal external of the filter assembly. The resettable air filter status indicator can be integrally formed in the sidewall for indicating if a mounted air filter member requires replacement in response to air intake differential pressure with respect to atmospheric pressure on a downstream side of air flow through the replaceable filter member being above a predetermined threshold value.

Abstract: A window shade system comprising a roller tube, a top casing, and a shade having a first end engaged with the roller tube and a second end engaged with the top casing such that the shade forms a bight between its ends that separates the shade into a front portion and a back portion. A rod is disposed in the bight. A lift mechanism, typically a motor, rotates the roller tube and moves the shade between a raised position where the bight is adjacent the top casing and a lowered position where the bight is distanced from the top casing. When the shade is in the lowered position, the front portion of the shade comprises a decorative fabric layer and the back portion comprises a sound attenuating layer, such as a polymer film with filler material or mass loaded vinyl. The window shade system typically comprises side casings that have channels for receiving the side edges of the shade.

Abstract: The present device is a suppression device for containing sound and germs emanating from a user's cough. A substantially hollow tube forms a gas conduit with a gas-permeable end membrane fixed within the tube across the gas conduit. A layer of a gas-permeable anti-bacterial material is fixed within the tube against the end membrane and a gas-permeable filter material is fixed within the tube against the anti-bacterial material. When a user needs to cough, the user coughs into the suppression device whereby the emanating germs and sound are suppressed as they encounter the filter material, the anti-bacterial material, and the end membrane. The suppression device further includes a lanyard permitting a user to wear the device and a label to write the user's name on the device. The suppression device is primarily comprised of biodegradable materials, allowing the suppression device to be disposable in an environmentally friendly way.

Abstract: A resonator for damping pressure waves or instabilities in a system supported by acoustic energy wherein the resonator adopts the use of counter-bored openings on the downstream side of the resonator within the flow path of the system. The resonator includes a first member and a second member where the second member includes a plurality of openings therethrough with each hole having a counter-bore on its upstream side. The first member has a size substantially smaller than the diameter of said flow path and a first plurality of openings therethrough. The openings are in fluid communication with the flow path. The second member has a size generally equal to the first member and a second plurality of openings therethrough, which openings are in fluid communication with the flow path.

Abstract: An exhaust system includes first and second exhaust components with an inter-pipe that fluidly connects an outlet of the first exhaust component to an inlet of the second exhaust component. A passive valve is mounted within the inter-pipe. The second exhaust component defines an internal cavity that is at least partially packed with a high frequency absorption material and cooperates with the passive valve to effectively attenuate low and high frequency noise.

Abstract: The present invention relates to an acoustic baffle device for sealing a cavity of a vehicle body at a predetermined cross section of the cavity, comprising a piece of sealing material that is formed in a shape corresponding to but being smaller than the shape of the cross section of the cavity. The acoustic baffle device of the invention is characterized in having a flap assembly having a lower neck defining a passage for a flexible tube or a similar device, said lower neck having a flap secured in closed position by a locking device and being connected preferably to the lower end of the lower neck through means that permit the reversible opening of the above-defined passage. Furthermore, the present invention relates to a flap assembly useful for such an acoustic baffle device, and to a process for sealing a cavity of a vehicle body at a predetermined cross section of the cavity.

Abstract: The invention relates to an acoustic panel assembly. There is a need for a simple and inexpensive acoustic panel assembly. An acoustic panel assembly includes a parent panel and an insert panel. The parent panel has a higher density body and a sound reflecting skin. The insert panel is mounted to the parent panel, and includes a sound absorbing body, a lower density rim and a sound transmitting skin. The parent panel includes a border portion which surrounds an opening which engages an outer edge of the insert panel. The border portion and the edge engage each other and form an interlocking joint. The border portion defines an annular groove which receives the outer edge of the insert panel. The body of the parent panel comprises a higher density expanded polypropylene material, and rim body of the insert panel comprises a lower density expanded polypropylene material.

Abstract: Aspects of the invention are directed to a system for improving the damping performance of an acoustic resonator. According to aspects of the invention, a resonator, such as a Helmholtz resonator, can be attached to a surface of a combustor component in a turbine engine. The combustor component includes a region in which a plurality of passages extend through the thickness of the component. The resonator is attached to the component so as to enclose at least some of the passages. The passages are in fluid communication with a cavity defined between the component surface and the resonator. Resonator performance is a function of the length of the passages in the component. According to aspects of the invention, resonator performance can be improved by reducing the length of the passages in the component by reducing the thickness of the component in a region that includes the plurality of passages.

Abstract: Aspects of the invention are directed to an acoustic resonator with improved impingement cooling effectiveness. The resonator includes a plate with an inside face and an outside face. A plurality of passages extend through the plate. The resonator includes a side wall that extends from and about the plate. A plurality of cooling tubes are attached to the resonator plate such that an inner passage of each cooling tube is in fluid communication with a respective passage in the resonator plate. The resonator can be secured to a surface of a turbine engine combustor component to define a closed cavity. The ends of the cooling tubes are spaced from the surface. Thus, a coolant can enter the passages in the plate and can be directed to the surface so as to impingement cool the surface. The cooling tubes can minimize coolant loss by dispersion in the cavity.

Abstract: A system for the noise reduction of wind turbines comprises at least one acoustic sensor provided at the wind turbine, a detection unit and a control unit, wherein said detection unit is adapted to detect tonal components in a signal of said sensor, and wherein said control unit is adapted to control wind turbine operating parameters in dependence of an amplitude of a tonal component.

Abstract: A door guard for hotel/motel doors comprises two articles, one article to be attached to a door, and another article to be attached to a door frame. One article is attached to the door, including a hook element adapted to receive a latch member of the door guard and attached to an inside surface of the door; and a damping element, composed of a sound dampening material, attached to an outside surface of the door. Another article is attached to the door frame, including a hinge element for connecting the article to the door frame; and a latch member pivotally connected to the hinge element. Another sound damping element, also composed of a sound dampening material, is disposed between the hinge element and the latch member. When the door guard is released and the door closes, the attached articles reduce the sound and/or vibrations, which are disturbing to hotel/motel guests, that occur when the closing door impacts the door guard and door frame.

Abstract: An engine and a generator driven by the engine are resiliently supported on a frame. A duct member is integrally attached to the engine and the generator to define a continuous cooling-air passage between the duct member and outer peripheral surfaces of the engine and the generator. A cooling fan is disposed on an inlet side of the cooling-air passage. A silencing plate is integrally attached to the duct member and faces an inlet of the cooling-air passage with a ventilation gap defined therebetween. The silencing plate has an area opposing the inlet that is larger than an opening area of the inlet.

Abstract: Repairs and overhaul procedures are scheduled and implemented with a surprisingly low frequency. Repair and overhaul procedures are implemented wherein conventional noise suppression exhaust sound attenuation systems receive structural and functional enhancements for promoting longevity of efficient system operations. Degradation deficiencies of conventional configurations of sound attenuation systems for exhaust augmenters and deflector panels are avoided or prevented so that insulation re-packing rates may be minimized. Apparatus and associated methodology establish and implement maintenance protocols for installing specially-designed kits in existing sound attenuation systems.

Abstract: Methods and apparatus are provided for an exhaust duct having an externally replaceable acoustic liner. The exhaust duct includes a forward section that is configured to be axially coupled with a bulkhead collar on the aircraft, a body section that is coupled to the forward section and a stinger cap that includes the replaceable acoustic liner. The replaceable acoustic liner is configured to be slideably received by the body section.

Abstract: A silencer for silencing and also for filtering exhaust gases, contains at least one acoustic resonator chamber (13, 14, 15, 16) (Helmholtz frequency), at least one porous body (7, 8) the porous body (7, 8) occupying at least part of the chamber and at least one connecting passage (17) for leading gas from each one of the acoustic chamber wherein the connecting passage (17) extend along the outher surface of the porous body, so as to lead along a helical flow path (19).

Abstract: A method and system for attenuating noise including arranging a plurality of accumulators (210, 310) to form a transmittance path for compressible flow mass and noise between a noise source (212, 312) and the external environment (218, 318), and selectively accumulating and confining compressible flow mass and noise within at least one of the plurality of accumulators, and attenuating noise confined within the at least one accumulator by ringdown. The system may include a plurality of interruptors/valves (220, 320) which are operated at respective timings for periodically accumulating and confining compressible flow mass and noise in at least one of the plurality of accumulators.

Abstract: An arrangement having an auxiliary heater, a catalytic converter (12) for catalytic post-combustion of exhaust gas from the heater, a muffler (14) for damping of the noise caused by the exhaust gas, and an exhaust line for removing exhaust gas from the auxiliary heater. In order especially to devise an auxiliary heater in which the muffler and the catalytic converter can be installed relatively easily, the muffler (14) and the catalytic converter (12) are combined in sing module (10) that can be located on the exhaust line.

Abstract: The invention concerns a suction muffler for a hermetically enclosed compressor with a housing that has at least a first and a second chamber, separated from each other by means of a division wall and connected with each other by means of a throttling channel, which is designed to allow flow from the first to the second chamber. The throttling channel includes a lateral opening, which opens into a chamber via a branch channel.

Abstract: A vehicle (1) having a sound-radiating element (10) for emitting sound waves into a passenger compartment (2) and having an air duct (6) for the air conditioning of the passenger compartment (2), the air duct (6) having an air duct inner wall (7) facing the passenger compartment (2). To reduce the installation space for the sound-radiating element and to simplify the assembly, the sound-radiating element (10) has the air duct inner wall (7) and an oscillation exciter (9) arranged on the air duct inner wall (7), for exciting oscillation of the air duct inner wall (7).

Abstract: A device to muffle and purify the exhaust gases from an internal combustion engine. A housing is divided into several chambers with the exhaust gases passing from one chamber to another, each successive chamber diverting the gas flow into an opposing direction. The first chamber is well insulated and contains a series of interconnected axial and equatorial tubes which provide multiple passageways with a large surface area which encourages repeated collisions of the gas molecules with the walls of the passages and with other molecules. While in this chamber the kinetic energy is greatly increased as is the temperature of the exhaust gases causing a break down of polluting molecules. Thereafter, the gases are directed alternately forward and rearward through several open chambers of increasing size which enable expansion and cooling of the gases and reduction of the associated noise. Finally the purified and cooled gases exit the last chamber into the atmosphere and pose no threat to the environment.

Abstract: An aircraft includes a spike projecting forward from the leading end of the fuselage and/or rearward from the trailing end of the fuselage. The spike can include a single section or two or more sections of varying cross-sectional area. Transition regions between sections of varying cross-sectional area are located and shaped to reduce coalescence of shock waves created thereby during supersonic flight. The spike can be collapsible and can be retracted into the fuselage. The spike can have a cross-sectional shape wherein the nose thereof lies on a line formed by the intersection of the bottom of the spike with a plane tangent to the bottom of the spike. A spike thus shaped causes an asymmetric pressure distribution during supersonic flight, wherein the ground-directed pressure contour is of lesser magnitude than the pressure contour propagating in other directions.

Abstract: An arrangement having an auxiliary heater, a catalytic converter (12) for catalytic post-combustion of exhaust gas from the heater, a muffler (14) for damping of the noise caused by the exhaust gas, and an exhaust line for removing exhaust gas from the auxiliary heater. In order especially to devise an auxiliary heater in which the muffler and the catalytic converter can be installed relatively easily, the muffler (14) and the catalytic converter (12) are combined in sing module (10) that can be located on the exhaust line.

Abstract: A vehicle seat cover is designed to facilitate acoustic energy absorption by forming in the cover an optimal size and arrangement of perforations based on a target noise frequency range, the perforations allowing the noise to pass through the cover into the interior structure of the seat where the acoustic energy is dissipated in the form of heat.

Abstract: A portable information terminal device has a plurality of casings providing a front surface and a rear surface, respectively. The casings have walls defining spaces in which speakers are housed and thicker than walls thereof that define a space in which a component including an internal circuit is housed. The walls defining the spaces in which speakers are housed are prevented from causing resonance due to vibrations of the speakers. The walls that define the space in which the component including the internal circuit is housed may be of a minimum thickness required irrespective of resonance caused by vibrations of the speakers. With the above arrangement, the portable information terminal device is small in size and weight.

Abstract: This invention relates to an acoustic liner for attenuating noise and consisting of a plurality of cells formed in a plate in a manner to form an array of resonators, and a fluid processing device and method incorporating same.

Abstract: A noise reducer for construction machinery, which efficiently reduces noise at low cost with durability, is provided. For this purpose, lamination plates (8) which are the plates being laminated are bonded, discretely at a predetermined interval (a1), to a part of or the entire of a noise generating element. Lamination plates (8A, 8E) may be bonded discretely at a plurality of kinds of bonding intervals (a1, a2). The lamination plates (8) with the different number of laminations may be bonded according to a noise generating element.

Abstract: A noise insulating member having a low degree of water absorbency and a low degree of oil absorbency. The noise insulating member includes a polyurethane foam obtained by reaction of an organic polyisocyanate component and a polyol component in the presence of a fluorine-containing surfactant, and having a cellular network having cells and communication holes which communicate with said cells. The communication holes have respective diameters each of which is not larger than 60 &mgr;m.

Abstract: The invention relates to a heat shield with acoustic insulation, comprised of a heat-shielding sheet which bears, on its side facing the heat- and acoustic noise-emitting source, a supporting sublayer bearing an acoustic absorption layer affixed to said sublayer, wherewith said supporting sublayer is disposed such that a defined air gap remains between the heat-shielding sheet and the supporting sublayer.

Abstract: A noise reducing diffuser which reduces the sound energy created by a pressurized gas while it is being expelled through a nozzle. The diffuser consists of an elongated enclosure with openings at each end that is attached to the output of the gas nozzle. The dimensions of the enclosure, particularly its distance from the sound source, effective diameter and length, are chosen to specifically eliminate audible noise created by the escaping gas by conversion of a portion of the longitudinal component of the sound energy to an increased radial component that can then be dissipated by repeated contact with the wall of the elongated enclosure.

Abstract: A combination comprises a muffler and a mounting band constructed and arranged to secure the muffler in a hanging orientation. The mounting band includes a continuous, arcuate metallic strap having first and second ends. The metallic strap is positioned in extension circumferentially around the muffler. The first and second ends of the metallic strap are welded to one another to retain the metallic strap as a continuous band around the muffler. The hanger is secured to a continuous portion of the metallic strap. The hanger is centered radially along the strap, at a location about 150.degree.-210.degree. from the weld of the strap ends.

Abstract: A heat shield apparatus, particularly for motor vehicle exhaust systems, which is coupled to and closely spaced from the heat source. The particular structure of the invention enables the mounting to be connected directly to the heat source while being behind the heat shield itself from the viewpoint of the heat source. The mounting is connected to the heat shield at positions where the temperature of the heat shield is substantially below its highest value.

Abstract: A plate-like body structure for a sound insulation wall having a built-in solar battery constituted by the combination of a built-in solar battery structure having a gentle convex arcuate shape so as to be installed on the top end portion of a sound insulation wall in the form of a head piece, and a built-in solar battery structure having a built-in solar battery plate-like body held by transparent plate-like materials from its opposite sides and inserted into a window-like opening portion or a wall holding frame portion formed in the sound insulation wall.

Abstract: A shield for mounting on a vehicle intermediate the passenger compartment and the exhaust system is formed as a sandwich of a fibrous layer between two heat reflecting layers. During the manufacturing process a hardenable resin impregnates the periphery of the fibrous layer and hardens in place to serve as an adhesive for bonding the layers together and providing a hard rigid mounting bracket. The fibrous layer intermediate its peripheral edges is relatively loosely held in place to serve as a sound absorbing barrier.

Abstract: A vertical exhaust system for an internal combustion engine that incorporates a provision for receiving and trapping water, such as rain, that may enter the open upper end of the exhaust conduit. The exhaust system includes a vertical outer body and a perforated tube is disposed within the outer body and spaced therefrom to provide an annular chamber therebetween. A plug or closure is secured within the tube and is spaced from the lower end of the tube, thus closing off the tube. An annular flange interconnects the inner tube with the outer body and is spaced longitudinally below the plug, to thereby enclose the lower end of the chamber. A drain hole extends through the outer body and connects the chamber with the exterior. The drain hole is spaced above the flange, so that the space between the flange and the drain hole comprises a trap to collect water that may enter the upper end of the exhaust system.