Hybrid ultra-wideband sound absorption superstructure and sound absorption module thereof

Abstract

The application discloses a mixed type ultrawideband sound absorption superstructure and a sound absorption module thereof, and relates to the field of acoustic noise reduction.The sound absorption superstructure comprises a resonance unit and a high-porosity sound absorption medium.The resonance unit comprises an outer shell, a rectangular channel and a cover plate.The cover plate is arranged in the outer shell, and divides the cavity in the outer shell into an upper space and a lower space.The rectangular channel is surrounded by two wall plates, the two wall plates are arranged in the lower space, and the top ends of the two wall plates are connected with the cover plate.The high-porosity sound absorption medium is filled in the upper space, the high-porosity sound absorption medium is provided with a sound wave guide channel, and the sound wave guide channel is coaxial with the rectangular channel.A through hole is arranged on the cover plate, so that the rectangular channel is connected with the high-porosity sound absorption medium.The application is applied to the field of acoustic noise reduction, and can overcome the defects of complex configuration, a large number of combined units, long development time, complex processing and installation, high cost and poor reliability of a traditional super material structure scheme for realizing low-frequency and ultrawideband high-efficiency sound absorption.

Description

Technical Field

[0001] This invention relates to the field of acoustic noise reduction technology, specifically a hybrid ultrawideband sound-absorbing superstructure and its sound-absorbing module. Background Technology

[0002] With the acceleration of industrialization and the improvement of urbanization, noise pollution has become one of the important factors affecting the quality of life and working environment. Effective noise control and treatment are of paramount importance in many fields, such as transportation equipment (airplanes, automobiles, high-speed trains), industrial equipment (generators, compressors), built environments (conference rooms, concert halls), and household appliances (air conditioners, refrigerators). The noise generated by these devices during operation not only affects equipment performance but also negatively impacts human health and comfort. Therefore, how to efficiently treat noise has become an urgent problem to be solved. However, existing noise treatment methods still have significant limitations in practical applications. First, the space available for acoustic treatment in practical applications is very limited. Achieving efficient noise absorption, especially low-frequency noise absorption, within this limited space is a major design challenge. Furthermore, noise treatment equipment must not only meet the requirements of efficient sound absorption and noise reduction but also consider the practical needs of mass production, low-cost manufacturing, and installation. This makes it difficult for existing sound absorption technologies to balance performance and cost. In particular, traditional sound-absorbing materials and technologies still face certain bottlenecks in low-frequency and ultra-wideband sound absorption, failing to meet the diverse needs of modern complex acoustic environments.

[0003] In recent years, with the development of acoustic physics and materials science, emerging technologies such as metamaterials and metastructures have provided new approaches to modern complex noise treatment. Metamaterials refer to artificially designed special structures that exhibit acoustic properties that cannot be achieved in nature, such as negative equivalent mass density and negative equivalent modulus. Compared with traditional sound-absorbing materials, metamaterials can achieve extraordinary control of low-frequency sound waves in thin-layer structures. Through the precise design of the internal structure of the material, it can meet the stringent requirements for low-frequency and ultra-wideband noise control within a limited installation space, and has broad application value in the field of vibration reduction and noise reduction.

[0004] Traditional sound absorption technologies mainly include resonant sound-absorbing structures such as micro-perforated panels and Helmholtz resonators, as well as porous sound-absorbing materials such as rock wool and foam. However, resonant sound-absorbing structures are typically effective at specific frequencies, with particularly outstanding low-frequency absorption performance, but their high-efficiency absorption bandwidth is relatively narrow, resulting in significant shortcomings in wide-band noise reduction. Porous sound-absorbing materials achieve energy attenuation through the interaction between sound waves in the air and the pore structure within the material, exhibiting good high-frequency sound absorption effects. However, their low-frequency absorption capacity often requires a large thickness, which contradicts the limited installation space in practical applications. Therefore, traditional sound absorption technologies often exhibit significant limitations when addressing the low-frequency and ultra-wideband sound absorption requirements of modern complex acoustic environments.

[0005] Furthermore, although emerging sound-absorbing metastructures or metastructure technologies have made significant progress and provided new solutions for noise treatment in modern complex acoustic environments, current metamaterial designs still have many shortcomings: First, they suffer from narrow sound absorption bandwidth or poor design flexibility. While some studies have achieved high-efficiency low-frequency sound absorption in thin layers, the absorption mechanism only works in the low-frequency range and cannot meet the high-efficiency sound absorption requirements in the mid-to-high frequencies. Second, the excessive number of constituent units results in a large sound absorber mass, failing to meet the lightweight requirements of most application scenarios. To address the problem of narrow high-efficiency sound absorption bandwidth, existing research on sound-absorbing metamaterials or metastructures mostly involves optimizing the design of sound absorber units with different resonance modes and combining them in parallel to broaden the high-efficiency sound absorption bandwidth. This means that the wider the required sound absorption bandwidth, the more sound absorber units need to be combined, inevitably resulting in a complex and large final sound absorber configuration, making it difficult to achieve engineering applications. Third, the structures are too complex, leading to high manufacturing costs and hindering mass production. Existing research on sound-absorbing metamaterials or metastructures mostly focuses on spatial structures, exhibiting complex spatial configurations and lengthy folded cavities. This limits the achievable manufacturing processes, resulting in high costs and long processing cycles, hindering large-scale application in practical noise control engineering. Furthermore, the complex configurations and processing techniques pose challenges to the durability, stability, and maintainability of the sound absorbers. Therefore, further research into novel sound-absorbing metamaterials or metastructures with simple configurations and the ability to achieve low-frequency ultra-wideband high-efficiency sound absorption in thin-layer structures holds significant research value and application prospects. Summary of the Invention

[0006] To address the shortcomings of the existing technologies, this invention provides a hybrid ultrawideband sound-absorbing superstructure and its sound-absorbing module. By cleverly combining multiple sound absorption mechanisms, it achieves high-efficiency sound absorption performance at low frequencies and ultrawideband speeds in a thin layer. Moreover, it has a simple configuration and low manufacturing cost. Using four or even fewer superstructure units, it can achieve high-efficiency ultrawideband sound absorption with almost no frequency limit while taking into account low frequencies. This overcomes the shortcomings of traditional metamaterial structure solutions in achieving high-efficiency sound absorption at low frequencies and ultrawideband speeds, such as complex configurations, massive number of combined units, long development time, complex processing and installation, high cost, and poor reliability.

[0007] To achieve the above objectives, the present invention provides a hybrid ultrawideband sound-absorbing superstructure, comprising a resonant unit and a high-porosity sound-absorbing medium;

[0008] The resonant unit includes an outer shell, a rectangular channel, and a cover plate. The outer shell is a cylindrical structure with one end open, formed by multiple surrounding walls. The cover plate is located inside the outer shell and divides the cavity inside the outer shell into an upper space and a lower space.

[0009] The rectangular passage is enclosed by two parallel wall panels, which are located in the lower space. The two sides of the two wall panels are connected to the surrounding wall, and the top of the two wall panels are connected to the cover plate.

[0010] The high-porosity sound-absorbing medium fills the upper space, and a sound wave guiding channel is provided on the high-porosity sound-absorbing medium; the sound wave guiding channel is a strip-shaped groove opened at the top of the high-porosity sound-absorbing medium, and the sound wave guiding channel is coaxial with the rectangular channel;

[0011] The two ends of the acoustic wave guiding channel are connected to the corresponding side of the enclosure wall, and the acoustic wave guiding channel may or may not penetrate the high porosity sound-absorbing medium along the axial direction; if the acoustic wave guiding channel penetrates the high porosity sound-absorbing medium along the axial direction, then the hybrid ultra-wideband sound-absorbing superstructure is a unidirectional equal cross-section configuration.

[0012] The cover plate has through holes that are consistent with the cross-section of the rectangular channel, so that the rectangular channel is connected to the high porosity sound-absorbing medium, thereby helping low-frequency sound waves that have passed through the high porosity sound-absorbing medium to enter the resonant unit and achieve efficient energy dissipation.

[0013] In one embodiment, the porosity of the high-porosity sound-absorbing medium is greater than or equal to 60%.

[0014] In one embodiment, the high-porosity sound-absorbing medium is made of one or more of the following: foam-type porous materials, inorganic fiber-type porous materials, organic fiber-type porous materials, and metallic porous materials.

[0015] In one embodiment, the cross-section of the acoustic wave guiding channel is made of one or more combinations of regular symmetrical polygons.

[0016] In one embodiment, the sound-absorbing superstructure further includes a high-transmission layer that covers the opening in the outer shell.

[0017] The high-transmittance acoustic layer is made of one or more of the following: high-permeability fiber cloth, fiber felt, polyester, cotton cloth, wire mesh, and perforated plate.

[0018] In one embodiment, the enclosure or the wall panel is made of one or more of the following: plastic board, gypsum board, metal board, plywood, hard fiberboard, acrylic board, tempered glass board, and composite material board.

[0019] To achieve the above objectives, the present invention also provides a hybrid ultra-wideband sound-absorbing module, comprising two or more of the above-mentioned hybrid ultra-wideband sound-absorbing superstructures, wherein each of the hybrid ultra-wideband sound-absorbing superstructures is combined in parallel.

[0020] In one embodiment, each of the hybrid ultrawideband sound-absorbing superstructures has different low-frequency resonance modes to achieve the low-frequency and ultrawideband high-efficiency sound absorption performance of the hybrid ultrawideband sound-absorbing module through coupling.

[0021] In one embodiment, on two adjacent hybrid ultrawideband sound-absorbing superstructures, the two high-porosity sound-absorbing media are separated by the enclosure wall, or the two high-porosity sound-absorbing media are integrally formed.

[0022] Compared with the prior art, the present invention has the following beneficial technical effects:

[0023] 1. This invention constructs a hybrid ultrawideband sound-absorbing superstructure through a multi-mechanism hybrid synergistic design, utilizing the ingenious structural design and efficient coupling with other high-efficiency sound-absorbing materials:

[0024] On the one hand, through ingenious collaborative design, the efficient coupling of two typical sound absorption mechanisms, resonant sound absorption and porous material sound absorption, is achieved. The reasonable layout of the porous material layer not only dissipates high-frequency sound waves significantly, but also allows low-frequency sound waves to freely penetrate to the resonant unit, significantly broadening the frequency band of efficient sound absorption, and achieving efficient sound absorption that optimizes low frequencies while taking into account mid and high frequencies.

[0025] On the other hand, by arranging the acoustic wave guiding channel and carrying out the coupling mechanism combination design with the interpolated rectangular channel, the acoustic wave is guided into the high porosity sound-absorbing medium and the low-frequency resonant unit, which reduces the reflection and dissipation of the acoustic wave into the environment and helps the acoustic energy to be fully dissipated in the high porosity sound-absorbing medium and the resonant unit. Among them, the acoustic wave guiding channel further increases the acoustic impedance to match the air acoustic impedance, balances energy loss and energy leakage, and greatly improves the low-frequency sound absorption performance of the sound-absorbing superstructure, achieving the goal of high-efficiency sound absorption at low frequencies and ultra-wideband under thin layers.

[0026] Furthermore, in the preferred embodiment, the hybrid ultra-wideband sound-absorbing superstructure of the present invention can be configured as a unidirectional equal cross-section structure. Depending on the limitations of the actual installation space or the needs of modular design, its length along the direction perpendicular to the equal cross-section can be designed to be any required length, so that the resonant unit therein can be manufactured using low-cost and reliable integrated molding processes such as extrusion molding and sheet metal bending, thereby achieving low-cost, large-scale, rapid, and efficient manufacturing.

[0027] 2. The hybrid ultrawideband sound-absorbing superstructure designed in this invention cleverly combines multiple sound absorption mechanisms to achieve high-efficiency sound absorption performance at low frequencies and ultrawideband under thin layers. Moreover, the configuration is simple and easy to develop. Using four or even fewer superstructure units, it is possible to achieve high-efficiency ultrawideband sound absorption with almost no frequency upper limit while taking into account low frequencies. This significantly reduces the number of couplings of ultrawideband sound-absorbing modules, simplifies the structural composition, and further reduces the structural manufacturing cost. It is beneficial to realize large-scale engineering applications and can effectively overcome the shortcomings of traditional metamaterial structural solutions in achieving high-efficiency sound absorption at low frequencies and ultrawideband, such as complex configuration, massive combination of units, long development time, complex processing and installation, high cost, and poor reliability. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0029] Figure 1 This is an isometric view of the sound-absorbing superstructure in Embodiment 1 of the present invention;

[0030] Figure 2 This is a perspective view of the sound-absorbing superstructure in Embodiment 1 of the present invention;

[0031] Figure 3 This is a cross-sectional view of the sound-absorbing superstructure in Embodiment 1 of the present invention;

[0032] Figure 4This is a schematic diagram of another embodiment of the sound-absorbing superstructure in Embodiment 1 of the present invention;

[0033] Figure 5 This is an isometric view of the sound-absorbing module in Embodiment 2 of the present invention under one implementation method;

[0034] Figure 6 This is an isometric view of the sound-absorbing module in Embodiment 2 of the present invention under another implementation method;

[0035] Figure 7 This is a cross-sectional view of the sound-absorbing module in Embodiment 2 of the present invention under one implementation method;

[0036] Figure 8 This is a cross-sectional view of the sound-absorbing module in Embodiment 2 of the present invention under another implementation method;

[0037] Figure 9 This is a sound absorption curve diagram of the sound-absorbing module in Embodiment 2 of the present invention under the configuration of Example 1;

[0038] Figure 10 This is a sound absorption curve diagram of the sound absorption module in Example 2 configuration in Embodiment 2 of the present invention.

[0039] Reference numerals: 1. Resonance unit; 101. Outer shell; 102. Rectangular channel; 103. Cover plate; 104. Wall panel; 105. Lower space; 2. High porosity sound-absorbing medium; 201. Sound wave guiding channel; 3. High sound wave transmission layer.

[0040] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0042] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0043] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two elements or the interaction between two elements, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0044] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0045] Example 1

[0046] like Figures 1 to 3 The above is a hybrid ultrawideband sound-absorbing superstructure (hereinafter referred to as "sound-absorbing superstructure") disclosed in this embodiment. It mainly includes a resonant unit 1 and a high-porosity sound-absorbing medium 2. The resonant unit 1 and the high-porosity sound-absorbing medium 2 are connected in series. The high-porosity sound-absorbing medium 2 is located above the resonant unit 1. There can be a transition air layer of a certain thickness between the two, thereby achieving efficient coupling of the two typical sound absorption mechanisms of resonant sound absorption and porous material sound absorption.

[0047] Specifically, the resonant unit 1 includes an outer shell 101, a rectangular channel 102, and a cover plate 103. The outer shell 101 is a cylindrical structure with one open end, formed by splicing multiple surrounding walls through methods such as adhesive bonding, snap-fit ​​connection, and integral molding. The cover plate 103 is fixed inside the outer shell 101 through methods such as adhesive bonding, snap-fit ​​connection, screw connection, and integral molding, and divides the cavity inside the outer shell 101 into an upper space and a lower space 105. The opening on the outer shell 101 is the end of the upper space. The rectangular channel 102 is formed by two parallel wall panels 104 located within the lower space 105. The sides of the two wall panels 104 are in contact with or glued to the corresponding side walls, and the tops of the two wall panels 104 are fixedly connected to the cover plate 103 through methods such as adhesive bonding, snap-fit ​​connection, screw connection, and integral molding. A high-porosity sound-absorbing medium 2 fills the upper space. The cover plate 103 has through holes with the same cross-section as the rectangular channel 102, allowing the rectangular channel 102 to connect with the high-porosity sound-absorbing medium 2. This facilitates the entry of low-frequency sound waves transmitted through the high-porosity sound-absorbing medium 2 into the resonant unit 1, achieving efficient energy dissipation. The resonant unit 1 has a sound absorption peak in the low-frequency range. The introduction of the high-porosity sound-absorbing medium 2 increases the acoustic impedance of the resonant unit 1, matching it with the air acoustic impedance, further reducing the resonant frequency of the sound absorption peak and broadening its efficient sound absorption bandwidth.

[0048] More specifically, the high-porosity sound-absorbing medium 2 is provided with a sound wave guiding channel 201. The cross-section of the sound wave guiding channel 201 is axisymmetric, and the sound wave guiding channel 201 is coaxial with the rectangular channel 102. This guides the sound waves to enter the resonant unit 1 and the high-porosity sound-absorbing medium 2 efficiently, avoiding the reflection of the sound waves to the environment and allowing the energy to be fully dissipated, thus realizing the ultra-wideband and high-efficiency sound absorption performance of the sound-absorbing superstructure.

[0049] In this embodiment, the acoustic wave guiding channel 201 is a strip-shaped groove formed at the top of the high-porosity sound-absorbing medium 2. Both ends of the acoustic wave guiding channel 201 are connected to the corresponding side walls, and the acoustic wave guiding channel 201 may or may not penetrate the high-porosity sound-absorbing medium 2 along the axial direction. That is, the overall sound-absorbing superstructure has a unidirectional uniform cross-section configuration. Therefore, the axial dimension of the acoustic wave guiding channel 201 can be designed to any required length according to the limitations of the actual installation space or the needs of modular design. This allows the resonant unit 1 in the sound-absorbing superstructure to be manufactured using low-cost, reliable, integrated molding processes such as extrusion molding and sheet metal bending, achieving low-cost, high-volume, rapid, and efficient manufacturing.

[0050] In this embodiment, the sound-absorbing superstructure, through the rational layout of the high-porosity sound-absorbing medium 2, not only significantly dissipates high-frequency sound waves but also allows low-frequency sound waves to freely penetrate and reach the resonant unit 1, significantly broadening the frequency band of the efficient sound absorption effect and achieving efficient sound absorption that optimizes low frequencies while also considering mid-to-high frequencies. On the other hand, by arranging the sound wave guiding channel 201 and implementing a coupling mechanism combination design with the intercalated rectangular channel 102, sound waves are guided into the high-porosity sound-absorbing medium 2 and the low-frequency resonant unit 1, reducing the reflection and dissipation of sound waves into the environment and contributing to the full dissipation of sound energy in the high-porosity sound-absorbing medium 2 and the resonant unit 1. Furthermore, the sound wave guiding channel 201 further increases the acoustic impedance to match the air acoustic impedance, balancing energy loss and energy leakage, significantly improving the low-frequency sound absorption performance of the sound-absorbing superstructure, and achieving the goal of efficient low-frequency and ultra-wideband sound absorption in a thin layer.

[0051] In the specific implementation process, the porosity of the high-porosity sound-absorbing medium 2 is greater than or equal to 60%, and it can be made of one or more of the following: foam-type porous materials, inorganic fiber-type porous materials, organic fiber-type porous materials, and metal-type porous materials. For example, it can be made by mixing one or more of asbestos, rock wool, sponge, glass wool, melamine foam, polyurethane foam, metal foam, and ceramic foam to form the high-porosity sound-absorbing medium 2.

[0052] In practical implementation, the cross-section of the acoustic wave guiding channel 201 is made of one or more combinations of regular symmetrical polygons such as rectangles, isosceles triangles, trapezoids, and rhombuses. For example, the cross-section of the acoustic wave guiding channel 201 can be directly set as an isosceles triangle, or the cross-section of the acoustic wave guiding channel 201 can be set as a combination of trapezoids and rhombuses. That is, the acoustic wave guiding channel 201 is divided into two integrally formed layers, with the first layer having a trapezoidal cross-section and the second layer having a rhombus cross-section.

[0053] refer to Figure 4 In a preferred embodiment, a high-transmittance sound wave layer 3 can also be arranged in the sound-absorbing superstructure. The high-transmittance sound wave layer 3 covers the opening of the outer shell 101, that is, it covers the high-porosity sound-absorbing medium 2, thereby preventing the high-porosity sound-absorbing medium 2 from being directly exposed to the acoustic treatment environment, thus improving its service life in harsh environments. The high-transmittance sound wave layer 3 can be made of one or more of the following: high-permeability fiber cloth, fiber felt, polyester, cotton cloth, wire mesh, and perforated plate, combined together.

[0054] In the specific implementation process, the enclosure or wall panel 104 can be made by splicing and combining one or more of the following: plastic board, gypsum board, metal board, plywood, hard fiberboard, acrylic board, tempered glass board, and composite material board.

[0055] Example 2

[0056] This embodiment discloses a hybrid ultrawideband sound-absorbing module (hereinafter referred to as "sound-absorbing module"), comprising two or more sound-absorbing superstructures as described in Embodiment 1. These sound-absorbing superstructures are combined in parallel, specifically in one or more columns, for example... Figure 5 , Figure 6 As shown. The depth of the sound-absorbing module can be adjusted by stretching the sound-absorbing superstructure with a constant cross-section.

[0057] In this embodiment, each sound-absorbing superstructure possesses a different low-frequency resonance mode. The thickness of the high-porosity sound-absorbing medium 2, the depth and width of the sound wave guiding channel 201, the width and length of the rectangular channel 102, and the heights of the upper and lower spaces 105 of each sound-absorbing superstructure can be set to be partially or completely different. For example... Figure 7 , Figure 8 As shown, the low-frequency and ultra-wideband high-efficiency sound absorption performance of the sound-absorbing module is achieved through coupling.

[0058] In the specific implementation process, on two adjacent hybrid ultrawideband sound-absorbing superstructures, two high-porosity sound-absorbing media 2 are separated by a surrounding wall, for example... Figure 7 As shown. Alternatively, on two adjacent hybrid ultrawideband sound-absorbing superstructures, part of the surrounding wall between the two high-porosity sound-absorbing media 2 can be removed, and a single piece of high-porosity sound-absorbing material with multiple sound wave guiding channels 201 can be used as filling, that is, the two high-porosity sound-absorbing media 2 are integrally formed, for example... Figure 8 As shown.

[0059] The sound-absorbing module in this embodiment will be further explained below with specific examples.

[0060] In Example 1, the configuration of the sound-absorbing module is as follows: Figure 5 As shown, the total height of the sound-absorbing module is 100mm, and it consists of four sound-absorbing superstructures connected in parallel in a 2×2 configuration. The geometric dimensions of the resonant unit 1 and the high-porosity sound-absorbing medium 2 in each sound-absorbing superstructure are different. Figure 9 The graph shows the sound absorption coefficient of the sound-absorbing module in Example 1. Figure 9 It can be seen that the sound absorption module has a sound absorption coefficient of over 0.8 in the low-frequency broadband range of 187 to 462 Hz, with an average sound absorption coefficient of 0.855.

[0061] In Example 2, the configuration of the sound-absorbing module is also as follows. Figure 5 As shown, the total height of the sound-absorbing module is 200mm, and it is also composed of four sound-absorbing superstructures connected in parallel in a 2×2 configuration. The difference from Example 1 is that the sound-absorbing module of Example 1 is mainly for broadband high-efficiency sound absorption in the low-frequency range (f≤500Hz), while the sound-absorbing module of Example 2 is mainly for high-efficiency sound absorption in both low-frequency and ultra-wideband applications.

[0062] Similarly, in Example 2, the geometric dimensions of the resonant unit 1 and the high-porosity sound-absorbing medium 2 are not consistent in each sound-absorbing superstructure. Figure 10 The sound absorption coefficient curve of the sound-absorbing module in Example 2 is shown in the figure. Figure 10 It can be seen that the sound-absorbing module maintains a sound absorption coefficient above 0.8 in the low-frequency ultra-wideband range of 100–10000Hz, with an average sound absorption coefficient of 0.959. Specifically, in the ultra-wideband range of 1795–10000Hz, the sound absorption coefficient is above 0.9, with an average sound absorption coefficient of 0.982. Furthermore, the sound absorption module consistently maintains a sound absorption coefficient above 0.95 in the frequency range above 10000Hz, achieving near-perfect sound absorption.

[0063] As can be seen from the results of Examples 1 and 2 above, this invention can achieve both broadband and efficient sound absorption in the low-frequency range (f≤500Hz) to address even lower-frequency acoustic treatments, and low-frequency and ultra-wideband efficient sound absorption with no upper limit on the efficient sound absorption frequency. Therefore, this invention possesses high design flexibility. For different acoustic treatment requirements, by optimizing the geometric parameters of the sound-absorbing module and combining different acoustic superstructures, it can adapt to corresponding installation environments and sound absorption performance requirements. By introducing a high-porosity sound-absorbing medium 2 with a sound wave guiding channel 201, the acoustic impedance of the resonant unit 1 is increased, balancing its energy loss and leakage, thereby matching it with the air acoustic impedance. This adjusts the resonant frequency and resonant mode of the resonant unit 1, significantly improving the sound absorption performance of low-frequency sound waves, giving the sound-absorbing module low-frequency, ultra-wideband, and efficient sound absorption performance.

[0064] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A hybrid ultra-wideband sound absorbing superstructure, characterized by, The resonant unit and the high porosity sound absorption medium are included. The resonant unit includes an outer shell, a rectangular channel and a cover plate, the outer shell is a cylindrical structure with one end open, surrounded by multiple surrounding walls, the cover plate is arranged in the outer shell, and the cover plate divides the cavity in the outer shell into an upper space and a lower space. The rectangular channel is surrounded by two parallel wall plates, both of which are located in the lower space, both sides of the wall plates are connected with the surrounding walls, and the top ends of the wall plates are connected with the cover plate. The high porosity sound absorption medium is filled in the upper space, and a sound wave guide channel is arranged on the high porosity sound absorption medium, the sound wave guide channel is a strip-shaped groove arranged on the top end of the high porosity sound absorption medium, and the sound wave guide channel is coaxial with the rectangular channel. Both ends of the sound wave guide channel are connected with the corresponding surrounding walls, and the sound wave guide channel penetrates or does not penetrate the high porosity sound absorption medium in the axial direction; if the sound wave guide channel penetrates the high porosity sound absorption medium in the axial direction, the mixed type ultra-wideband sound absorption superstructure is a single-section configuration; the sound wave guide channel guides the sound wave into the high porosity sound absorption medium and the low-frequency resonant unit, reduces the reflection and dispersion of the sound wave to the environment, helps the full dissipation of sound energy in the high porosity sound absorption medium and the resonant unit, and achieves the purpose of high-efficiency sound absorption in a thin layer, low frequency and ultra-wideband. A through hole with the same cross section as the rectangular channel is arranged on the cover plate, so that the rectangular channel is connected with the high porosity sound absorption medium, thereby helping the low-frequency sound wave transmitted through the high porosity sound absorption medium to enter the resonant unit and realizing high-efficiency energy dissipation.

2. The hybrid UWB sound absorbing superstructure according to claim 1, characterized in that, The porosity of the high porosity sound absorption medium is greater than or equal to 60%.

3. The hybrid UWB sound absorbing superstructure of claim 1, wherein, The high porosity sound absorption medium can be made of one or more than two combinations of foam porous materials, inorganic fiber porous materials, organic fiber porous materials and metal porous materials.

4. The hybrid UWB sound absorbing superstructure of claim 1, wherein, The cross section of the sound wave guide channel can be made of one or more than two combinations of regular symmetric polygons.

5. The hybrid UWB sound absorbing superstructure of claim 1, wherein, A sound wave high-transmission layer is further included, which covers the opening of the outer shell. The sound wave high-transmission layer can be made of one or more than two combinations of high-air-permeability fiber cloth, fiber felt, polyester, cotton cloth, silk screen and perforated plate.

6. The hybrid UWB sound absorbing superstructure of claim 1, wherein, The surrounding walls and the wall plates are made of one or more than two combinations of plastic plates, gypsum boards, metal plates, plywood, hard fiber boards, acrylic plates, tempered glass plates and composite material plates.

7. A hybrid ultra-wideband sound absorption module, characterized by Two or more than two mixed type ultra-wideband sound absorption superstructures according to any one of claims 1 to 6 are included, and each mixed type ultra-wideband sound absorption superstructure is combined in parallel.

8. The hybrid ultra-wideband sound absorption module of claim 7, wherein, Each mixed type ultra-wideband sound absorption superstructure has at least two different low-frequency resonance modes to realize the high-efficiency sound absorption performance of the mixed type ultra-wideband sound absorption module in low frequency and ultra-wideband through coupling effect.

9. The hybrid ultra-wideband sound absorption module of claim 7, wherein, In the two adjacent mixed type ultra-wideband sound absorption superstructures, the two high porosity sound absorption media are separated by the surrounding walls, or the two high porosity sound absorption media are integrally formed.

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