105 results about "Sound Absorber" patented technology

The invention discloses an underwater sound absorber with low-frequency broadband sound absorption and high pressure bearing performance and a design method of the underwater sound absorber. The sound absorber comprises a plurality of hexagonal honeycomb units which are spliced in sequence. Each honeycomb unit is composed of a hexagonal metal honeycomb framework, a rubber coating, a special-shaped embedded neck part and a cavity. The hexagonal honeycomb framework forms a hexagonal cylindrical cavity, the side wall and the bottom plate of the honeycomb framework are coated with the rubber coating, the acoustic impedance of the rubber coating is matched with the underwater acoustic impedance, and sound wave energy can be effectively absorbed. The special-shaped embedded neck part is embedded into the cavity of the honeycomb framework, and the neck part structure protrudes inwards, so that the vibration velocity and the hot sticking loss of sound waves are remarkably improved. The cavity is formed by a honeycomb framework and a rubber coating and used for storing sound energy and providing a resonance space. Multi-path dissipation and broadband sound absorption of sound energy are achieved through viscoelastic dissipation of the rubber coating and hot viscous loss of the special-shaped embedded neck part, and the composite material has remarkable potential application value in the field of underwater low-frequency noise control.

The invention discloses a bent channel-Helmholtz composite low-frequency broadband sound absorber and a design method thereof. The sound absorber is formed by connecting a plurality of bent channel metamaterial sound absorption units around a Helmholtz resonator unit in parallel in a coupling mode. By controlling the impedance of the Helmholtz neck and the impedance of the bending channel, each unit is in an under-loss state, and then the overall critical coupling is realized by utilizing the area coupling effect, so that the sound absorber has the sound absorption coefficient of more than or equal to 0.5 in the frequency band of 267-382Hz under the thickness of 35mm. According to the sound absorber, broadband efficient sound absorption is achieved through impedance coupling of the Helmholtz resonators and the bent channels, the problems that a traditional structure is narrow in frequency band, difficult to regulate and control and the like are solved, and theoretical and technical supports are provided for low-frequency noise control.

The present application relates to a sound absorber (1) for acoustic shielding, comprising a planar base body in which several strip-shaped sections (2a) are formed parallel to one another, each of the strip-shaped sections (2a) having two opposite edges and at least one recess (4) extending along the strip-shaped section (2a), which projects from the planar base body and through which an opening (5) with side edges (6a, 6b) is formed at each of the opposite edges. The recess (4) has an edge (4a) extending transversely to the strip-shaped section (2a) and is subdivided by the edge (4a) along the strip-shaped section (2a) into a first recess area (4b) with first side edges (6a) and a second recess area (4c) with second side edges (6b). The first side edges (6a) are curved differently than the second side edges (6b).

A laser chamber according to an aspect of the present disclosure includes a container, a first electrode, a second electrode, and a sound absorber. The container is filled with a laser gas. The first electrode is disposed in the container. The second electrode is disposed in the container and faces the first electrode. The sound absorber is disposed on at least one of an upstream side and a downstream side of the laser gas from the first electrode. The sound absorber is configured to cause a propagation speed of an acoustic wave generated in a discharge space between the first electrode and the second electrode to decrease as a distance from the discharge space increases.

The invention discloses a firmly-connected assembly type noise reduction floor, and belongs to the technical field of assembly floors, the firmly-connected assembly type noise reduction floor comprises a vibration reduction panel and a sound absorption base, the vibration reduction panel is mounted at the top of the sound absorption base, the sound absorption base comprises a sound insulation supporting box, and a plurality of first sound absorbers and a plurality of second sound absorbers are arranged in the sound insulation supporting box; the first sound absorbers and the second sound absorbers are evenly distributed in an array mode, sound conducted from bottom to top is absorbed through the first sound absorbers, sound conducted from top to bottom is absorbed through the second sound absorbers, and the vibration reduction panel comprises a first vibration reduction plate. A second vibration reduction plate, a third vibration reduction plate, a fourth vibration reduction plate and a sound insulation supporting plate are sequentially arranged on the lower portion of the first vibration reduction plate from top to bottom, the sound insulation supporting plate and a sound insulation supporting box are mutually clamped and fixed, various scratching and scraping damages in the external environment are borne, various liquid pollutants and solid pollutants are blocked, overall damage and pollution are avoided, and the sound insulation effect is good. And a user can conveniently take care.

The present invention discloses a subwavelength ventilated asymmetric sound absorber, which is composed of one or more absorption cells. The absorption cell includes a metamaterial resonator and a backing impedance boundary. The backing impedance boundary includes a rear panel, a top panel, a bottom panel, a long plate and a short plate, which together form an L-shaped structure; a flow port is provided on the upper portion of the rear panel to facilitate airflow; the bottom of the metamaterial resonator is placed on the short plate of the backing impedance boundary, and a channel is left between it and the bottom plate of the backing impedance boundary; the back of the metamaterial resonator is fixedly connected to the side of the long plate of the backing impedance boundary, and a channel is left between it and the rear panel of the backing impedance boundary. The deep subwavelength absorber of the present invention can almost perfectly absorb the sound energy incident from the loss end and almost perfectly reflect the sound energy incident from the opposite end, has a good suppressive effect on broadband noise, and can achieve ventilation and heat dissipation functions while controlling noise.

The invention relates to a vehicle pneumatic tire comprising at least one sound absorber adhesively attached to an internal surface opposite the tread inside the tire, wherein the at least one sound absorber is adhered to an adhesive, and to an adhesive composition for fixing at least one sound absorber to the surface of a vehicle pneumatic tire. The adhesive contains at least the following ingredients: - from 10% to 80% by weight of at least one rubber, and - from 11% to 80% by weight of at least one polyolefin, and - from 2% to 20% by weight of at least one hydrocarbon resin. The adhesive has optimized flow characteristics and optimized tackiness.

The utility model discloses a composite absorption device for enhancing low frequency sound absorption, which belongs to the technical field of pipeline acoustics black holes, and comprises a sound tube, a plurality of micro-perforated plates and a Helmholtz sound absorber, the micro-perforated plates are distributed at equal intervals along the axial direction of the inlet end of the sound tube and are arranged from large to small according to the perforated distribution area, and the Helmholtz sound absorber is arranged on the sound tube. Micro-pores are uniformly distributed in each micro-perforated plate; every two adjacent micro-perforated plates are connected through a separation ring; the Helmholtz sound absorbers are distributed at equal intervals in the axial direction of the outlet end of the sound tube, the diameters of the gradually-changed embedded necks are gradually reduced, the center of each Helmholtz sound absorber is provided with a gradually-changed embedded neck, and the inner diameter of each gradually-changed embedded neck is gradually reduced from the inlet end to the outlet end; every two adjacent Helmholtz sound absorbers are connected through a sound absorber cavity. According to the utility model, through the combination of the composite gradually-changed micro-perforated plate and the gradually-changed cascaded Helmholtz sound absorbers which are embedded in the neck part, low-frequency sound absorption and medium-high frequency broadband sound absorption are realized under the sub-wavelength length.

The application discloses a low-frequency broadband sound absorber, which comprises a resonator, the outer part of the resonator is covered with a porous material layer, one side of the porous material layer is connected with a rigid backing, and the side opposite to the rigid backing is an incident surface; the resonator comprises an inner shell and an outer shell, the inner shell is located inside the outer shell; a first opening is arranged at the center of one side of the outer shell close to the sound wave incident surface, a second opening is arranged at the center of one side of the inner shell close to the rigid backing, and the first opening and the second opening are oppositely arranged. The application can efficiently absorb sound waves in a wide band range of low-frequency waves, and the high-efficiency absorption effect is hardly affected by the sound wave incident angle.

This invention discloses a broadband duct silencing structure combining perforated tubes and cavities. The structure uses a galvanized housing as its main body, with perforated tubes coaxially arranged inside. A perforated partition divides the structure into front and rear silencing chambers. The front silencing chamber contains a first sound absorber and an air layer, forming a Helmholtz resonant cavity to efficiently eliminate low-frequency fan noise. The rear silencing chamber is filled with a second sound absorber and is equipped with perforated tubes, micro-perforated tubes, and micro-perforated inserts with progressively smaller apertures, forming a gradient microporous structure to achieve broadband absorption of mid-to-high frequency noise. The structure utilizes the airflow in the duct to drive the impeller to rotate, which in turn drives a bidirectional reciprocating screw via bevel gear transmission. This drives a delivery rod and a one-way valve to form a directional airflow circulation. The sound absorber is automatically purged through the air duct and comb-shaped air duct to remove fiber dust, preventing secondary pollution and stabilizing acoustic performance. This invention combines the advantages of low-frequency resonance silencing and mid-to-high frequency gradient microporous sound absorption, featuring a compact structure, wide silencing bandwidth, and stable and reliable operation.

The invention relates to a curable and preferably polymer composition that is useful as a sealant, an adhesive (e.g., structural adhesive), a reinforcement, a dampener, a sound absorber or any combination thereof. The composition preferably comprises one or more ethylene polymers, tackifier, curing agent, and rheology modifier. The invention also relates to extrusion of the composition onto an article surface, e.g. through a robotically mounted extrusion die, and subsequent activation for curing by an external stimulus.

The utility model relates to a mounting structure of an array type silencer, which comprises a shell, an accommodating space is arranged in the shell, the front end and the rear end of the accommodating space are respectively provided with an opening, and a fixing frame is arranged on the outer side of the shell in a surrounding manner; the silencer assembly is arranged in the shell and comprises sound absorbers and flow guide covers, the flow guide covers are fixedly arranged at the two ends of the sound absorbers, the sound absorbers are arranged in the containing space in an array mode, and the flow guide covers are fixedly connected with the shell; the longitudinal section of the sound absorber is wave-shaped; the supporting rod is arranged in the shell, a through hole penetrating through the upper end face and the lower end face is formed in the flow guide cover, the supporting rod penetrates through the through hole and is connected with the fixing frame, and the supporting rod is fixedly connected to the flow guide cover. By adopting the structure, the effective length of the sound absorber is increased, so that the silencing effect of the silencer is effectively improved.

The present technology relates to an information processing apparatus, method, and program that enable sound field control having a higher degree of freedom. The information processing method of the present invention involves an information processing apparatus performing the following: identifying a parameter relating to the complex acoustic impedance of a resonator, or a sound absorber that uses the resonator, installed on a surface forming a target space, said parameter being identified on the basis of a target sound pressure frequency characteristic at an evaluation point in the target space and an acoustic analysis model for obtaining the sound pressure frequency characteristic at any point in the target space; and identifying the shape of the sound absorber on the basis of the parameter. The present technology can be applied to an acoustic metamaterial.

Example implementations relate to a method and system of cooling a computing system, while simultaneously absorbing airborne noise in the computing system. The computing system includes a chassis having a base and a pair of walls coupled to a peripheral side of the base, and a plurality of rotational drives disposed in the chassis. The computing system includes a frame having a plurality of first openings, and a first acoustic absorber having a plurality of second openings, coupled to the frame to form an acoustic absorber frame. The acoustic absorber frame extends along a lateral direction, disposed downstream relative to the plurality of rotational drives, and coupled to the pair of walls. Each second opening is concentrically aligned to a respective first opening. The computing system includes a plurality of fans coupled to frame and disposed downstream relative to the frame, and aligned to the respective first opening.

According to the complex closed space global low-frequency noise reduction method based on the active micro-perforated plate sound absorber, an active control technology is introduced into a small-size MPPA, the low-frequency acoustic reactance of a cavity of the MPPA is reduced by offsetting the sound field of the cavity of the MPPA, and the sound energy dissipation performance of the MPP is improved by breaking the waveform matching of the sound fields on the two sides of the MPP; the noise of the whole complex closed space is reduced in an active sound absorption mode, and meanwhile the problem that the noise reduction performance of some medium-high frequency resonance frequency points is weak due to coupling of a closed space sound field and an MPPA cavity sound field can be solved. The invested active control measure is low in cost, and the low-frequency noise reduction performance of the complex closed space is remarkable, so that the method has important engineering application value.

The present invention relates to the field of noise control and specifically provides a composite broadband noise reduction superstructure, comprising a mid-high frequency noise reduction body and a low-frequency broadband noise reduction body; the mid-high frequency noise reduction body comprises an incident perforated plate and a second sound absorber; the low-frequency broadband noise reduction body comprises a plurality of parallel sound absorbing units, each comprising a top perforated plate, a back closed plate, a side closed plate, and a closed partition; at least one internal perforated plate is disposed within the cavity of the sound absorbing unit, the top perforated plate being connected to the second sound absorber of the mid-high frequency noise reduction body; the internal perforated plate divides the sound absorbing unit into two or more series-connected sound absorbing chambers, each of which is provided with a first sound absorber; the sound absorbing chambers comprise a rearmost sound absorbing chamber and a front sound absorbing chamber, into which sound waves enter via the incident perforated plate, the second sound absorber, and the top perforated plate. This solution is applicable to broadband noise sources of various frequency domains or multi-order harmonic noise sources, can reduce the effective sound absorption frequency, and achieve full-band noise reduction through the composite mid-high frequency noise reduction body and low-frequency broadband noise reduction body superstructure.

The utility model relates to a ventilation equipment technical field especially a noise reduction type fan box device. The device includes the fan cabinet and sets up in its fan assembly, the inner wall of fan cabinet is attached with composite sound absorption cotton board to constitute primary sound absorption structure, the air outlet of fan assembly is connected with sound absorption assembly through hose joint, the sound absorption assembly includes the sound absorber and several character shape flow channel sound absorption box connected in proper order, constitutes secondary sound absorption and tertiary sound absorption structure. The utility model through in the inner wall, air outlet and export flow channel carry out multistage, compound type sound absorption and damping design, effectively widened the noise reduction frequency band, especially significantly reduced low frequency noise, guaranteed good ventilation performance simultaneously, compact structure, maintenance is convenient, effectively solved the problem that the frequency band is limited, the volume is heavy and the durability is poor in the existing fan box noise reduction technology.

To construct a sound absorber with excellent designability capable of easily changing an indoor sound environment, and improve comfort of a room using the sound absorber.SOLUTION: A sound absorber 10 comprises: a self-supporting rectangular frame body 11 with a part of an outside surface serving as a bottom part; a first membrane body 12 closing a first opening 11a on one end side of the frame body 11; a second membrane body 13 closing a second opening 11b on the other end side of the frame body 11; and a sound absorption material 14 made of a porous material, which is arranged inside the frame body 11. The first membrane body 12 and the second membrane body 13 are made of different materials. The first and second membrane bodies 12, 13, together with the first and second openings 11a, 11b, integrally cover front end surfaces 15a, 16a and outside surfaces 15b, 16b of first and second frame members 15, 16, and their peripheral edge parts extend to inside surfaces 15d, 16d of the first and second frame members 15, 16, and are fixed to the inside surfaces 15d, 16d.SELECTED DRAWING: Figure 2

The invention relates to the technical field of automobile sound-absorbing cotton detection, and particularly discloses a stretching detection device for automobile sound-absorbing cotton processing, which comprises an identification structure, a stretching device and a fixing device, and is characterized in that the identification structure is used for detecting the offset of the automobile sound-absorbing cotton after stretching; the stretching device is arranged at the front end of the top face of the bottom of the recognition structure and can synchronously stretch the two ends of the automobile sound-absorbing cotton. The number of the fixing devices is two, the two fixing devices are symmetrically arranged at the two output ends of the stretching device correspondingly, the two fixing devices can fix the two ends of the automobile sound-absorbing cotton, and the fixing devices have universality and can be suitable for automobile sound-insulating cotton of different thicknesses; the fixing device can be matched with the stretching device to carry out cotton stretching detection on automobile sound absorbers with different thicknesses; according to the invention, the stability, the detection precision and the detection quality of automobile sound-absorbing cotton detection data are effectively improved, and a reliable basis is provided for sound-absorbing cotton processing quality judgment.

The invention relates to a heat activatable, volume expandable and curable polymer composition for use as a sealant, an adhesive, a reinforcement, a dampener, and / or a sound absorber, preferably for automotive vehicles. The polymer composition is preferably pumpable and / or extrudable and has a high degree of volume expansion upon heat activation. The polymer composition is capable of bridging large gaps between substrates and filling cavities of large volume, respectively. The invention further relates to a method of producing an automotive vehicle assembly wherein a bead of the polymer composition is directly applied onto a surface of a vehicle component by means of an applicator, preferably a pump or an extruder, more preferably a pneumatic- or electric driven piston gun and optionally dispensing equipment. After immersing the vehicle component with the applied bead on its surface in one or more liquid baths and subsequently removing from said baths, the polymer composition is heated to an elevated temperature to induce curing and volume expansion of the polymer composition providing a cured foam with a low foam density.

The utility model provides a chemical silencer for multi-frequency noise suppression, which relates to the technical field of silencers and comprises a main body, an external silencing pipe arranged at the top of the main body, a connecting pipe arranged at the bottom of the main body, supporting legs arranged at the bottom of the outer side of the main body, a supporting base arranged at the bottoms of the supporting legs, and a resonance sound absorber arranged at the top end in the main body. A cavity is formed in the main body, a built-in silencing barrel is arranged in the center of the cavity, a sound insulation plate is arranged on the outer side of the silencing barrel, a damping spring is arranged at the bottom of the sound insulation plate, multiple pieces of silencing cotton, a filtering layer, the silencing barrel, a sound absorber and a silencing pipe are adopted, multi-layer inhibition on multi-frequency noise is achieved, and noise is simply and effectively reduced.

The plate-type sound absorber with shock-absorbing function comprises a top plate and a bottom plate, a partition plate is arranged between the top plate and the bottom plate, through holes are arranged on the top plate, the bottom plate and the partition plate, upper sound absorbing cotton is arranged between the top plate and the partition plate, lower sound absorbing cotton is arranged between the bottom plate and the partition plate, a damping pad is arranged at the bottom of the lower sound absorbing cotton, and a shock-absorbing plate is arranged between the damping pad and the lower sound absorbing cotton. The plate-type sound absorber adopts the structure of top plate-upper sound absorbing cotton-partition plate-lower sound absorbing cotton-damping pad-bottom plate, thereby enhancing the sound absorption effect of the plate-type sound absorber. In addition, the shock-absorbing plate is additionally arranged between the lower sound absorbing cotton and the damping pad, so that the plate-type sound absorber has the shock-absorbing function, thereby avoiding damage of the plate-type sound absorber due to collision and prolonging the service life of the plate-type sound absorber.

The invention discloses a fan cavity noise reduction device, a control method and an air conditioner, the fan cavity noise reduction device is applied to a fan cavity, and the fan cavity noise reduction device comprises a micro-perforated plate arranged in the fan cavity, and the micro-perforated plate comprises a back cavity. The micro-perforated plate can be regarded as an acoustic element with acoustic resistance and acoustic quality, the micro-perforated plate is installed in front of the back cavity, a certain cavity is reserved behind the back cavity, in this way, a resonance sound absorber can be formed, and noise reduction is conducted on the fan cavity through the resonance sound absorption effect. In addition, different micro-perforated plate specification parameters such as the thickness, the hole diameter and the back cavity depth of the micro-perforated plate can be set based on the actual situation, the specification parameters can influence the sound absorption coefficient of the structure, and therefore the micro-perforated plate specification parameter most conforming to the actual scene is selected, and the fan noise control effect is improved.

The invention relates to a vehicle tyre (100) comprising: - a tyre inner side (101) which surrounds a tyre cavity (102), - a sound absorber (120), - an adhesive bond (140), wherein the sound absorber (120) is fastened to the tyre inner side (101) by means of the adhesive bond (140), and wherein the adhesive bond (140) has a reinforcing structure (141), - a grip region (150) which is coupled to the reinforcing structure (141) in order to release the adhesive bond (140) from the tyre inner side (101) by means of a movement of the grip region (150).

The invention discloses a micropore integrally-formed acoustic diffusion sound absorber and a preparation method. The micropore integrally-formed acoustic diffusion sound absorber comprises a sound absorption functional layer; the sound absorption structure comprises a base supporting layer, a sound absorption functional layer and a micropore diffusion layer, the sound absorption functional layer is arranged on the base supporting layer, the micropore diffusion layer is arranged at the bottom of the sound absorption functional layer, and a plurality of through diffusion holes are formed in the micropore diffusion layer, and the sound absorption structure has the following beneficial effects that through the sound absorption functional layer, the micropore diffusion layer and the base supporting layer, the sound absorption structure is integrally formed by multiple layers of composite materials; the three layers are a basic supporting layer, a micropore diffusion layer and a sound absorption function layer, all the layers are tightly combined through a specific technology to form an integrated structure, when sound waves are incident, diffusion holes can enable the sound waves to generate multiple times of reflection and scattering, sound amplification and gradient aperture design are carried out to promote uniform diffusion of sound wave energy, and the sound absorption function layer effectively converts the diffused sound energy into heat energy. Progressive attenuation of sound energy is formed by the whole structure, and it is guaranteed that the sound absorption structure can have the dual functions of sound wave diffusion and absorption at the same time.

For the purpose of providing a transducer (203) capable of improving assemblability, a plurality of transceiver units (1), each of the transceiver units (1) comprises a sound absorber (52, 53), a plurality of transducer elements (2) arranged on the sound absorber (52, 53) in an arcuate shape and with the transmitting and receiving surfaces facing outward in the arcuate radial direction, and a flexible substrate (3, 4) having a plurality of junctions (33, 43) connected to the first connection surfaces (22) of a pair of connection surfaces facing the arcuate axial direction of the plurality of transducer elements (2).

The utility model discloses a rock wool space sound absorber with a composite structure, and belongs to the technical field of sound absorption structures, the rock wool space sound absorber with the composite structure is characterized by comprising an outer frame, and a composite sound absorption assembly is arranged in the outer frame. The interception structure reflects sound waves in a specific frequency band and converts part of sound energy into heat energy to be consumed according to the unique design of the interception structure and the reflection sound reduction principle, the high-frequency noise is remarkably weakened, the rock wool layer located in the outer frame gives full play to the porous sound absorption characteristic of the rock wool layer, sound shuttles among fiber pores of the rock wool layer, and the sound absorption effect is improved. Due to the effects of friction, viscosity and the like, a large amount of sound energy is converted and absorbed, the sound energy does not release any absorbable sound energy like a layer-by-layer filter screen, the sound energy and the sound energy supplement each other, and both high-frequency sharp noise and low-frequency dull roar can be effectively intercepted.

The pipeline silencer comprises a shell and a silencing assembly arranged in the shell, the silencing assembly comprises a first silencing section, a second silencing section and a third silencing section which are connected with one another, the first silencing section comprises a first silencing cylinder and a plurality of silencing pieces obliquely arranged in the first silencing cylinder, and the third silencing section comprises a second silencing cylinder and a plurality of silencing pieces obliquely arranged in the second silencing cylinder. The second silencing section comprises a first connecting cylinder, a second silencing cylinder and a second connecting cylinder which are connected with one another, the diameter of the second silencing cylinder is larger than that of the first silencing cylinder, the third silencing section is made of a third silencing cylinder, and a plurality of silencing holes are formed in the cylinder wall of the third silencing cylinder. According to the pipeline silencer, the silencing assembly is arranged, the silencing cotton is arranged on the inner cylinder wall of the first silencing cylinder, and the silencing sheet is obliquely arranged on the pipe wall of the first silencing pipe, so that the contact time of airflow and the sound absorption structure is longer, and the utilization rate of the sound absorption structure is higher; therefore, the sound absorption efficiency in the cavity of the whole sound absorber is high.

The invention discloses a 3D (three-dimensional) hollow composite roof applied to a large-span railway vehicle, which sequentially comprises an outer skin layer, an upper bearing layer, a three-dimensional hollow woven core layer, a lower bearing layer and an interior base layer from outside to inside, and is characterized in that the three-dimensional hollow woven core layer is formed by integrally weaving Z-direction penetrating fiber columns and X-direction or Y-direction space rib belts; a hollow cavity with a variable aperture can be formed, and aerogel, a micropore sound absorber, a phase change temperature control material, flame-retardant ceramic fibers or electromagnetic shielding metal fibers can be filled in the cavity according to requirements. The top plate is integrally formed by adopting a three-stage resin injection curing process, so that fibers are continuously penetrated in three directions, and the interlayer stripping risk is thoroughly eliminated. Through the synergistic effect of the three-dimensional overall structure design and the functional materials, remarkable light weight, excellent bending and shearing strength and good sound insulation and heat insulation performance are achieved, and the requirements for flame retardance and electromagnetic shielding can be met. The process can form a large-size integral top plate, and has the advantages of high structural reliability, high function integration level and the like.

The application relates to a combined acoustic black hole sound absorption body structure and a design method. The structure comprises a cross-shaped partition plate, a cylindrical cavity, a bottom plate, four groups of 1 / 4 annular thin plate arrays, the number ratio of the four groups of 1 / 4 annular thin plate arrays is 30:25:20:17, the plate thickness and the interval are equal, the cross-shaped partition plate divides the cylindrical cavity into four independent 1 / 4 cylindrical cavities with equal volumes, the four groups of 1 / 4 annular thin plate arrays are respectively located in the four 1 / 4 cylindrical cavities, and the bottom plate is located at one end of the 1 / 4 annular thin plate without an annular partition plate with the smallest inner diameter and seals the end. The application calculates the sound absorption coefficient of the combined acoustic black hole sound absorption body by constructing a transfer matrix model of a single 1 / 4 acoustic black hole sound absorption body, and optimizes the structure length of the single 1 / 4 acoustic black hole sound absorption body and the number of 1 / 4 annular thin plates, so that the structure can stably absorb the medium and high frequency noise. The application has the advantages of simple structure, low cost and stable wideband sound absorption.