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

Abstract

The invention discloses a mixed type ultra-wideband sound absorption superstructure and a sound absorption module thereof. 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, and the cover plate is arranged in the outer shell and divides a cavity in the outer shell into an upper-layer space and a lower-layer space; the rectangular channel is defined by two wall plates, the two wall plates are located in the lower-layer space, and the top ends of the two wall plates are connected with the cover plate. The upper-layer space is filled with the high-porosity sound absorption medium, a sound wave guide channel is formed in the high-porosity sound absorption medium, and the sound wave guide channel and the rectangular channel are coaxial; a through hole is formed in the cover plate, so that the rectangular channel is connected with the high-porosity sound absorption medium. The invention is applied to the field of acoustic noise reduction, and can overcome the defects of complex configuration, huge combination units, long development time, complex processing and installation, high cost, poor reliability and the like when a traditional metamaterial structure scheme is used for realizing low-frequency and ultra-wide-band efficient sound absorption.

Description

Technical Field

[0001] The invention relates to the technical field of acoustic noise reduction, in particular to a hybrid ultra-wideband sound absorption superstructure and a sound absorption module thereof. Background Art

[0002] With the acceleration of industrialization and the improvement of urbanization, noise pollution has become one of the important factors affecting the quality of human life and working environment. Effective control and treatment of noise are extremely important in many fields, such as transportation equipment (aircraft, automobiles, high-speed rail), industrial equipment (generators, compressors), building environment (conference rooms, concert halls), household appliances (air conditioners, refrigerators), etc. The noise generated by these equipment during operation not only affects the performance of the equipment, but also has a negative impact on human health and living comfort. Therefore, how to efficiently handle noise has become a difficult problem to be solved. However, the existing noise treatment methods still have great limitations in practical applications. First of all, in the equipment used in actual applications, the space that can be used for acoustic treatment is very limited. How to achieve efficient noise absorption in a limited space, especially the absorption of low-frequency noise, is a major challenge faced in the design. In addition, noise treatment equipment must not only meet the requirements of efficient sound absorption and noise reduction, but also must consider the actual needs of mass production, low-cost manufacturing and installation, which makes it difficult for existing sound absorption technology to balance performance and cost. In particular, in terms of low-frequency and ultra-wideband sound absorption, traditional sound absorption materials and technologies still have certain bottlenecks and cannot meet the diverse needs in modern complex acoustic environments.

[0003] In recent years, with the development of acoustic physics and materials science, emerging technologies such as metamaterials or metastructures have provided new ideas for modern complex noise processing. Metamaterials refer to special structures with artificial design, and 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 a thin layer structure, and through the fine design of the internal structure of the material, it can meet the stringent noise control requirements of low frequency and ultra-wideband in 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 absorption structures such as micro-perforated plates and Helmholtz resonators, as well as porous sound absorption materials such as rock wool and foam materials. However, resonant sound absorption structures usually effectively absorb sound at specific frequencies, and their low-frequency sound absorption performance is particularly outstanding, but their high-efficiency sound absorption bandwidth is relatively narrow, and there are obvious deficiencies in wide-band noise processing. Porous sound-absorbing materials achieve energy attenuation through the interaction between sound waves in the air and the pore structure inside the material, and have good high-frequency sound absorption effects, but their sound absorption capacity in the low-frequency band often requires a large thickness as a price, which is contrary to the limited installation space in practical applications. Therefore, traditional sound absorption technology often shows great limitations when dealing with low-frequency and ultra-wideband sound absorption needs in modern complex acoustic environments.

[0005] In addition, although the emerging sound-absorbing superstructure or superstructure technology has made great progress and provided new solutions for noise treatment in modern complex acoustic environments, the current metamaterial design still has many shortcomings: First, the sound absorption bandwidth is narrow or the design flexibility is poor. Some studies have achieved low-frequency and efficient sound absorption under thin layers, but the sound absorption mechanism can only act on the low-frequency range and cannot take into account the efficient sound absorption requirements of medium and high frequencies. Second, too many components cause the sound absorber to be heavy and cannot meet the lightweight requirements of most application scenarios. In order to solve the problem of narrow bandwidth of efficient sound absorption, most of the existing research on sound-absorbing metamaterials or superstructures optimizes the design of sound absorber units with different resonance modes and combines them in parallel to broaden the bandwidth of efficient sound absorption. This means that the wider the sound absorption bandwidth requirement, the more sound absorber units are needed to be combined, which will inevitably cause the final sound absorber configuration to be complex and heavy, making it difficult to achieve engineering applications. Third, the structure is too complex, the manufacturing cost is high, and it is difficult to mass produce. Existing research on sound-absorbing metamaterials or superstructures is mostly spatial structures, with relatively complex spatial configurations and lengthy folded cavities. The achievable production and processing technology is relatively limited, and the cost is high, the processing cycle is long, and it is difficult to apply them in large quantities in actual noise control projects. In addition, the complex configuration and processing technology also pose challenges to the durability, stability and later maintainability of the sound absorber. Therefore, further research and development of new sound-absorbing metamaterials or superstructures with simple configurations and mass production that can achieve low-frequency ultra-wideband high-efficiency sound absorption in a thin layer structure has important research value and application prospects. Summary of the invention

[0006] In view of the deficiencies in the above-mentioned prior art, the present invention provides a hybrid ultra-wideband sound absorption superstructure and a sound absorption module thereof, which achieves low-frequency and ultra-wideband efficient sound absorption performance in a thin layer by cleverly mixing multiple sound absorption mechanisms, and has a simple configuration and low processing and manufacturing cost. By using 4 or even fewer superstructure units, ultra-wideband efficient sound absorption with almost no frequency upper limit and taking into account low frequencies can be achieved, overcoming the deficiencies faced by traditional metamaterial structure solutions in achieving low-frequency and ultra-wideband efficient sound absorption, such as complex configuration, huge number of combination units, long development time, complex processing and installation, high cost and poor reliability.

[0007] To achieve the above object, the present invention provides a hybrid ultra-wideband sound absorbing superstructure, comprising a resonance unit and a high-porosity sound absorbing medium;

[0008] The resonance unit comprises an outer shell, a rectangular channel and a cover plate, wherein the outer shell is a cylindrical structure surrounded by a plurality of surrounding walls and having one end open, and 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;

[0009] The rectangular channel is surrounded by two parallel wall panels, the two wall panels are located in the lower space, the two sides of the two wall panels are connected to the surrounding wall, and the top ends of the two wall panels are connected to the cover plate;

[0010] The high-porosity sound-absorbing medium is filled in 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 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 surrounding wall on the corresponding side, and the acoustic wave guiding channel axially penetrates or does not penetrate the high-porosity sound absorbing medium; if the acoustic wave guiding channel axially penetrates the high-porosity sound absorbing medium, the hybrid ultra-wideband sound absorbing superstructure as a whole is a unidirectional uniform cross-section configuration;

[0012] The cover plate is provided with a through hole consistent with the cross section of the rectangular channel, so that the rectangular channel is connected to the high-porosity sound-absorbing medium, thereby facilitating low-frequency sound waves transmitted through the high-porosity sound-absorbing medium to enter the resonance unit, thereby achieving 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 a combination of two or more of foam-type porous materials, inorganic fiber-type porous materials, organic fiber-type porous materials, and metal-type porous materials.

[0015] In one embodiment, the cross-section of the sound wave guiding channel is made of one or a combination of two or more regular symmetrical polygons.

[0016] In one embodiment, the sound absorbing superstructure further includes a high sound wave transmission layer, and the high sound wave transmission layer covers the opening of the outer shell;

[0017] The high sound wave transmission layer is made of one or a combination of two or more of highly breathable fiber cloth, fiber felt, polyester, cotton cloth, silk screen, and perforated plate.

[0018] In one embodiment, the surrounding wall and the wall panel are made of one or a combination of two or more of plastic board, gypsum board, metal board, plywood, hard fiberboard, acrylic board, tempered glass board, and composite material board.

[0019] To achieve the above object, the present invention further provides a hybrid ultra-wideband sound absorbing module, comprising two or more of the above hybrid ultra-wideband sound absorbing superstructures, wherein the hybrid ultra-wideband sound absorbing superstructures are combined in parallel.

[0020] In one embodiment, each of the hybrid ultra-wideband sound absorbing superstructures has a different low-frequency resonance mode, so as to achieve the low-frequency and ultra-wideband efficient sound absorption performance of the hybrid ultra-wideband sound absorbing module through coupling.

[0021] In one of the embodiments, on two adjacent hybrid ultra-wideband sound absorbing superstructures, the two high-porosity sound absorbing media are separated by the surrounding 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. The present invention constructs a hybrid ultra-wideband sound-absorbing superstructure through multi-mechanism hybrid collaborative design, with the help of ingenious structural design and efficient coupling with reasonable connection of other high-efficiency sound-absorbing materials:

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

[0025] On the other hand, by laying out the sound wave guiding channel and carrying out the combined design of the coupling mechanism with the inserted rectangular channel, the sound waves are guided into the high-porosity sound-absorbing medium and the low-frequency resonance unit, which reduces the reflection and dispersion of the sound waves to the environment and helps to fully dissipate the sound energy in the high-porosity sound-absorbing medium and the resonance unit. Among them, the sound wave guiding channel further increases the acoustic resistance to match the air acoustic impedance, balances the energy loss and energy leakage, and greatly improves the low-frequency sound absorption performance of the sound-absorbing superstructure, achieving the purpose of efficient sound absorption at low frequency and ultra-wideband in a thin layer;

[0026] In addition, the hybrid ultra-wideband sound absorbing superstructure of the present invention can be set as a unidirectional uniform cross-section configuration in the preferred embodiment, and its dimension along the direction perpendicular to the uniform cross-section can be designed to any required length according to the limitation of the actual installation space or the need of modular design, so that the resonance unit therein can adopt low-cost and reliable integrated molding processes such as extrusion molding and sheet metal bending, so as to achieve low-cost, large-scale, rapid and efficient manufacturing;

[0027] 2. The hybrid ultra-wideband sound absorption superstructure designed by the present invention cleverly mixes multiple sound absorption mechanisms to achieve low-frequency and ultra-wideband efficient sound absorption performance in a thin layer, and has a simple configuration and is easy to develop. It can achieve ultra-wideband efficient sound absorption with almost no frequency upper limit and taking low frequency into consideration by using 4 or even fewer superstructure units, which greatly reduces the number of couplings of ultra-wideband sound absorption modules, simplifies the structural composition, and further greatly reduces the structural manufacturing cost, which is beneficial to the realization of large-scale engineering applications, and can effectively overcome the shortcomings of traditional metamaterial structural solutions in achieving low-frequency and ultra-wideband efficient sound absorption, such as complex configuration, huge number of combination units, long development time, complex processing and installation, high cost, and poor reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0029] Figure 1 is an axonometric diagram of the sound absorbing superstructure in Example 1 of the present invention;

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

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

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

[0033] Figure 5 is an axonometric diagram of a sound absorption module in Example 2 of the present invention in one implementation manner;

[0034] Figure 6 is an axonometric diagram of the sound absorption module in Example 2 of the present invention under another implementation mode;

[0035] Figure 7 is a cross-sectional view of a sound absorbing module in Example 2 of the present invention in one implementation manner;

[0036] Figure 8 is a cross-sectional view of a sound absorbing module in Example 2 of the present invention in another implementation manner;

[0037] Fig. 9 is a sound absorption curve diagram of the sound absorption module in Example 2 of the present invention under the configuration of Example 1;

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

[0039] Reference numerals: resonance unit 1 , outer shell 101 , rectangular channel 102 , cover plate 103 , wall plate 104 , lower space 105 , high-porosity sound-absorbing medium 2 , sound wave guiding channel 201 , sound wave high-transmittance layer 3 .

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

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

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

[0043] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0045] Example 1

[0046] like Figures 1 to 3 The figure shows a hybrid ultra-wideband sound absorbing superstructure (hereinafter referred to as "sound absorbing superstructure") disclosed in the present embodiment, which mainly includes a resonance unit 1 and a high-porosity sound absorbing medium 2. The resonance unit 1 and the high-porosity sound absorbing medium 2 are connected in series, and the high-porosity sound absorbing medium 2 is located above the resonance unit 1. A transition air layer of a certain thickness may exist between the two, thereby achieving efficient coupling of two typical sound absorption mechanisms of resonance sound absorption and porous material sound absorption.

[0047] Specifically, the resonance 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 an opening at one end, which is formed by splicing multiple surrounding walls by means of gluing, snap connection, integrated molding, etc. The cover plate 103 is fixed in the outer shell 101 by means of gluing, snap connection, screw connection, integrated molding, etc., and the cover plate 103 divides the cavity in the outer shell 101 into an upper space and a lower space 105, and the opening on the outer shell 101 is the end of the upper space. The rectangular channel 102 is surrounded by two parallel wall panels 104, the two wall panels 104 are located in the lower space 105, the two sides of the two wall panels 104 are in contact with the corresponding side surrounding walls or glued and fixed, and the tops of the two wall panels 104 are fixedly connected to the cover plate 103 by means of gluing, snap connection, screw connection, integrated molding, etc. The high-porosity sound-absorbing medium 2 is filled in the upper space, and a through hole consistent with the cross section of the rectangular channel 102 is provided on the cover plate 103, so that the rectangular channel 102 is connected to the high-porosity sound-absorbing medium 2, thereby facilitating the low-frequency sound waves transmitted through the high-porosity sound-absorbing medium 2 to enter the resonance unit 1, and realizing efficient energy dissipation. The resonance unit 1 has a sound absorption peak in the low-frequency band. The introduction of the high-porosity sound-absorbing medium 2 increases the acoustic impedance of the resonance unit 1, making it match the acoustic impedance of air, further reducing the resonant frequency of the sound absorption peak, and broadening the efficient sound absorption bandwidth of the sound absorption peak.

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

[0049] In this embodiment, the sound wave guiding channel 201 is a strip groove opened at the top of the high-porosity sound absorbing medium 2, and the two ends of the sound wave guiding channel 201 are connected to the surrounding walls of the corresponding sides, and the sound wave guiding channel 201 axially penetrates or does not penetrate the high-porosity sound absorbing medium 2. That is, the whole sound absorbing superstructure is a unidirectional uniform cross-section configuration, and then the axial dimension of the sound wave guiding channel 201 can be designed to be any required length according to the limitation of the actual installation space or the needs of modular design, so that the resonance unit 1 in the sound absorbing superstructure can adopt low-cost and reliable integrated molding processes such as extrusion molding and sheet metal bending, so as to achieve low-cost, large-scale, fast and efficient manufacturing.

[0050] The sound-absorbing superstructure in this embodiment not only dissipates high-frequency sound waves to a large extent by rationally arranging the high-porosity sound-absorbing medium 2, but also allows low-frequency sound waves to freely penetrate and reach the resonance unit 1, significantly broadening the frequency band of efficient sound absorption, and realizing efficient sound absorption that optimizes low frequencies and takes into account medium and high frequencies. On the other hand, by arranging the sound wave guiding channel 201 and carrying out a combined design of the coupling mechanism with the inserted rectangular channel 102, the sound waves are guided into the high-porosity sound-absorbing medium 2 and the low-frequency resonance unit 1, reducing the reflection and dissipation of the sound waves to the environment, and contributing to the full dissipation of sound energy in the high-porosity sound-absorbing medium 2 and the resonance unit 1. Moreover, the sound wave guiding channel 201 further increases the acoustic resistance to match the air acoustic impedance, balances the energy loss and energy leakage, and greatly improves the low-frequency sound absorption performance of the sound-absorbing superstructure, achieving the purpose of efficient sound absorption at low frequencies and ultra-wideband under 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 can be made of one or a combination of two or more of foam-type porous materials, inorganic fiber-type porous materials, organic fiber-type porous materials, and metal-type porous materials. For example, the high-porosity sound-absorbing medium 2 is composed of a mixture of one or more of asbestos, rock wool, sponge, glass wool, melamine foam, polyurethane foam, metal foam, and ceramic foam.

[0052] In the specific implementation process, the cross section of the sound wave guiding channel 201 is made of one or more combinations of regular symmetrical polygons such as rectangles, isosceles triangles, trapezoids, rhombuses, etc. For example, the cross section of the sound wave guiding channel 201 can be directly set to an isosceles triangle, or the cross section of the sound wave guiding channel 201 can be set to a combination of trapezoids and rhombuses, that is, the sound wave guiding channel 201 is divided into two integrally formed layers, the cross section of the first layer is a trapezoid, and the cross section of the second layer is a rhombus.

[0053] refer to Figure 4 As a preferred embodiment, a high sound wave transmission layer 3 can also be arranged in the sound absorbing superstructure, and the high sound wave transmission layer 3 covers the opening of the outer shell 101, that is, 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, thereby increasing its service life in harsh environments. Among them, the high sound wave transmission layer 3 can be made of one or more splicing combinations of highly breathable fiber cloth, fiber felt, polyester, cotton cloth, silk screen, and perforated plate.

[0054] In the specific implementation process, the surrounding wall and the wall panel 104 can be made of one or a combination of two or more of 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 ultra-wideband sound absorption module (hereinafter referred to as "sound absorption module"), comprising two or more sound absorption superstructures in Embodiment 1, each sound absorption superstructure is combined in parallel, specifically, it can be connected in parallel into one or more rows, for example Figure 5 , Figure 6 The depth of the sound absorbing module can be adjusted by stretching the sound absorbing superstructure with equal cross-section.

[0057] In this embodiment, each sound absorbing superstructure has a different low-frequency resonance mode, and the thickness of the high-porosity sound absorbing medium 2, the depth of the sound wave guiding channel 201, the width of the sound wave guiding channel 201, the width of the rectangular channel 102, the length of the rectangular channel 102, and the height of the upper space and the lower space 105 of each sound absorbing superstructure can be set to be partially or completely different, for example Figure 7 , Figure 8 As shown, the coupling effect enables the low-frequency and ultra-wideband efficient sound absorption performance of the sound absorption module.

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

[0059] The sound absorption module in this embodiment is further described below with reference to 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 100 mm, and it is composed of four sound absorbing superstructures connected in parallel in a 2×2 form, wherein the geometric dimensions of the resonance unit 1 and the high-porosity sound absorbing medium 2 in each sound absorbing superstructure are inconsistent. Fig. 9 is the sound absorption coefficient curve of the sound absorption module in Example 1, Fig. 9 It can be seen that the sound absorption coefficient of the sound absorption module is above 0.8 in the low-frequency broadband range of 187 to 462 Hz, and the average sound absorption coefficient reaches 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 absorption module is 200 mm, and it is also composed of 4 sound absorption superstructures connected in parallel in a 2×2 form. The difference from Example 1 is that the sound absorption module of Example 1 is mainly aimed at broadband efficient sound absorption in the low frequency range (f≤500Hz), while the sound absorption module of Example 2 is mainly aimed at low frequency and ultra-broadband efficient sound absorption.

[0062] Example 2 Similarly, the geometrical dimensions of the resonance unit 1 and the high-porosity sound absorbing medium 2 in each sound absorbing superstructure are not consistent. Fig.10 The sound absorption coefficient curve of the sound absorption module in Example 2 is shown by Fig.10 It can be seen that the sound absorption coefficient of the sound absorption module is above 0.8 in the low-frequency ultra-wideband range of 100 to 10,000 Hz, and the average sound absorption coefficient reaches 0.959. Among them, in the ultra-wideband range of 1,795 to 10,000 Hz, the sound absorption coefficient is above 0.9, and the average sound absorption coefficient reaches 0.982. In addition, the sound absorption coefficient of the sound absorption module in the frequency range above 10,000 Hz remains above 0.95, which is almost perfect sound absorption.

[0063] From the results of the above examples 1 and 2, it can be seen that the present invention can not only achieve broadband and efficient sound absorption within the low-frequency range (f≤500Hz), which is used to deal with lower-frequency acoustic processing situations, but also achieve low-frequency and ultra-wideband efficient sound absorption, and there is no upper limit to the efficient sound absorption frequency. Therefore, the present invention has a high degree of design flexibility. According to different acoustic processing requirements, by optimizing the geometric parameters of the sound absorption module and combining different acoustic superstructures, it can adapt to the corresponding installation environment and sound absorption performance requirements. By introducing a high-porosity sound absorption medium 2 with a sound wave guiding channel 201, the acoustic impedance of the resonance unit 1 is increased, and its energy loss and leakage are balanced, thereby matching it with the air acoustic impedance, adjusting the resonant frequency and resonance mode of the resonance unit 1, and significantly improving the sound absorption performance of low-frequency sound waves, so that the sound absorption module has low-frequency, ultra-wideband and efficient sound absorption performance.

[0064] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A hybrid ultra-wideband sound absorbing superstructure, characterized in that: It includes a resonance unit and a high-porosity sound-absorbing medium; The resonance unit comprises an outer shell, a rectangular channel and a cover plate, wherein the outer shell is a cylindrical structure surrounded by a plurality of surrounding walls and having one end open, and 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 panels, the two wall panels are located in the lower space, the two sides of the two wall panels are connected to the surrounding wall, and the top ends of the two wall panels are connected to the cover plate; The high-porosity sound-absorbing medium is filled in 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 groove opened at the top of the high-porosity sound-absorbing medium, and the sound wave guiding channel is coaxial with the rectangular channel; The two ends of the acoustic wave guiding channel are connected to the surrounding wall on the corresponding side, and the acoustic wave guiding channel axially penetrates or does not penetrate the high-porosity sound absorbing medium; if the acoustic wave guiding channel axially penetrates the high-porosity sound absorbing medium, the hybrid ultra-wideband sound absorbing superstructure as a whole is a unidirectional uniform cross-section configuration; The cover plate is provided with a through hole consistent with the cross section of the rectangular channel, so that the rectangular channel is connected to the high-porosity sound-absorbing medium, thereby facilitating low-frequency sound waves transmitted through the high-porosity sound-absorbing medium to enter the resonance unit, thereby achieving efficient energy dissipation.

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

3. The hybrid ultra-wideband sound absorbing superstructure according to claim 1, characterized in that: The high-porosity sound-absorbing medium can be made of one or a combination of two or more of a foam-type porous material, an inorganic fiber-type porous material, an organic fiber-type porous material, and a metal-type porous material.

4. The hybrid ultra-wideband sound absorbing superstructure according to claim 1, characterized in that: The cross section of the sound wave guiding channel may be made of one or a combination of two or more regular symmetrical polygons.

5. The hybrid ultra-wideband sound absorbing superstructure according to claim 1, characterized in that: It also includes a high sound wave transmission layer, which covers the opening of the outer shell; The high sound wave transmission layer can be made of one or a combination of two or more of highly breathable fiber cloth, fiber felt, polyester, cotton cloth, silk screen, and perforated plate.

6. The hybrid ultra-wideband sound absorbing superstructure according to claim 1, characterized in that: The surrounding wall and the wallboard are made of one or a combination of two or more of plastic board, gypsum board, metal board, plywood, hard fiberboard, acrylic board, tempered glass board and composite material board.

7. A hybrid ultra-wideband sound absorption module, characterized in that: The invention comprises two or more hybrid ultra-wideband sound absorbing superstructures according to any one of claims 1 to 6, wherein each of the hybrid ultra-wideband sound absorbing superstructures is combined in parallel.

8. The hybrid ultra-wideband sound absorption module according to claim 7, characterized in that: Each of the hybrid ultra-wideband sound absorbing superstructures has at least two different low-frequency resonance modes, so as to achieve the low-frequency and ultra-wideband efficient sound absorption performance of the hybrid ultra-wideband sound absorbing module through coupling.

9. The hybrid ultra-wideband sound absorption module according to claim 7, characterized in that: On two adjacent hybrid ultra-wideband sound absorbing superstructures, the two high-porosity sound absorbing media are separated by the surrounding wall, or the two high-porosity sound absorbing media are integrally formed.

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