Multi-cavity sound insulation module and sound insulation structure based on Helmholtz resonance

Abstract

The invention discloses a multi-cavity sound insulation module and a sound insulation structure based on Helmholtz resonance, and belongs to the technical field of acoustic metamaterials, the multi-cavity sound insulation module comprises a shell, the shell is filled with a plurality of thin-film acoustic metamaterials arranged along the width of the shell or the length of the shell in a stacked mode, and the thin-film acoustic metamaterials are arranged in the shell in a stacked mode. A gap is formed between every two adjacent film acoustic metamaterials, a first through hole is formed in the middle of one side of the shell, and the rest part of the shell is sealed, so that a resonant cavity is formed; when the thin-film acoustic metamaterials are arranged along the width direction of the shell, each thin-film acoustic metamaterial is provided with a first through hole, and the first through hole is communicated with the first through hole; when the thin-film acoustic metamaterials are arranged in the length direction of the shell, the first through holes are communicated with the gaps, a multi-cavity resonance structure is formed through superposition use of the multi-layer thin-film acoustic metamaterials, and each cavity can effectively absorb noise of a specific frequency band.

Description

Technical Field

[0001] The present invention relates to the technical field of acoustic metamaterials, and in particular to a multi-cavity sound insulation module and a sound insulation structure based on Helmholtz resonance. Background Art

[0002] Sound insulation technology is increasingly used in modern industry and life, especially in the fields of construction, transportation, manufacturing, etc. Effective sound insulation measures can significantly reduce noise pollution and improve the comfort of the working environment and production efficiency. Traditional sound insulation methods mainly rely on heavy materials and complex structural designs. Although they can achieve a certain sound insulation effect, they have great limitations in terms of lightweight and compactness. In recent years, with the development of new materials and new technologies, sound insulation devices based on the Helmholtz resonance principle have gradually become a research hotspot. Their unique design concept can simplify and optimize the structure while ensuring efficient sound insulation.

[0003] Existing sound insulation devices based on Helmholtz resonance mainly include single-cavity or multi-cavity structures. The common single-cavity structure usually adopts a closed cavity with a small hole set in the cavity, and uses the resonance effect generated by the vibration of the air column to absorb noise in a specific frequency band. However, the sound insulation range of this single-cavity structure is limited, and it is difficult to cover wide-band noise. In order to broaden the sound insulation frequency band, the researchers proposed the design idea of ​​a multi-cavity structure, that is, arranging multiple small cavities in a larger shell, each small cavity has an independent small hole, and by adjusting the size and position of each cavity, effective absorption of noise in different frequency bands can be achieved. In addition, another commonly used method is to fill the shell with sound-absorbing materials, such as foam plastics, mineral wool, etc. These materials can further enhance the sound insulation effect.

[0004] Although the above multi-cavity structure and filling method have improved the sound insulation performance to a certain extent, there are still some shortcomings. First, the complexity and manufacturing difficulty of the multi-cavity structure are high, resulting in increased costs and difficult maintenance. Second, a single multi-cavity structure or filling method is often only effective for noise in a specific frequency band, and has limited ability to handle broadband noise.

[0005] Therefore, how to achieve effective sound insulation against broadband noise while keeping the structure simple and easy to manufacture is a technical problem that needs to be solved urgently. Summary of the invention

[0006] The present invention provides a multi-cavity sound insulation module and a sound insulation structure based on Helmholtz resonance, which can achieve effective sound insulation for a wide frequency range.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] A multi - cavity sound insulation module based on Helmholtz resonance, comprising a housing. A number of thin - film acoustic metamaterials arranged along the width or the length of the housing are stacked and filled inside the housing. There is a gap between adjacent thin - film acoustic metamaterials. A first through - hole is opened in the middle of one side of the housing, and the rest of the housing is hermetically arranged to form a resonance cavity. When the thin - film acoustic metamaterials are arranged along the width direction of the housing, a first perforation is opened on each thin - film acoustic metamaterial, and the first through - hole is communicated with the first perforation. When the thin - film acoustic metamaterials are arranged along the length direction of the housing, the first through - hole is communicated with the gap.

[0009] Preferably, the technical solution of the present invention is that the thin - film acoustic metamaterial includes a central mass block, a mass ring, and a thin film. There are m mass rings, where m is a natural number greater than 1. The m mass rings are arranged from the center outwards in sequence. The mass rings are arranged around the periphery of the central mass block and are enclosed to form a ring. The material of the thin film is metal or metal alloy. The first perforation is opened on the central mass block; the first through - hole is coaxial with the first perforation.

[0010] Preferably, the technical solution of the present invention is that the thin - film acoustic metamaterial includes a central mass block, a mass ring, and a thin film. There are m mass rings, where m is a natural number greater than 1. The m mass rings are arranged from the center outwards in sequence. The mass rings are arranged around the periphery of the central mass block and are enclosed to form a ring. The material of the thin film is metal or metal alloy. There are m thin films, and the m thin films are arranged from the center outwards in sequence. The nth thin film is arranged inside the nth mass ring, where n is any natural number greater than or equal to 1 and less than or equal to m. The area surrounded by the nth mass ring forms the nth - order acoustic metamaterial. The central mass block is fixed on the first thin film. The first perforation is opened on the central mass block; the first through - hole is coaxial with the first perforation.

[0011] Preferably, the technical solution of the present invention is that the mass rings are symmetrically arranged on both sides of the thin film, and the central mass block is arranged on one side of the first thin film; the height of the mass rings gradually increases from the center outwards; the thickness of the thin film ≤ 0.2 mm; the mass rings are square or circular or regular hexagon or triangle.

[0012] Preferably, the technical solution of the present invention is that the material of the mass ring is steel or aluminum alloy or carbon fiber or engineering ABS plastic; the material of the thin film is stainless steel or aluminum alloy; the material of the central mass block is stainless steel.

[0013] Preferably, in the technical solution of the present invention, the thicknesses and / or materials of the n thin films are all different; three mass rings are provided, and four thin films are provided.

[0014] Preferably, in the technical solution of the present invention, the height of the central mass block is h mass、 with a mass of M mass ; the height of the nth mass ring is h n and the mass is M frame,n , where the height of the mass ring is the distance between the topmost end and the bottommost end of the mass ring; the stiffness of the nth thin film is K n ; the natural frequency of the nth-order acoustic metamaterial is f n , and the calculation formula for the natural frequency of the first-order acoustic metamaterial is as follows The calculation formula for the natural frequency of the nth-order acoustic metamaterial is where Mn is the equivalent mass of the nth thin film at the center, and M e,n-1 is the equivalent mass of the (n - 1)th-order acoustic metamaterial; the Young's modulus of the nth thin film is E, the thickness is d, and the Poisson's ratio is μ. The thickness of the thin film is calculated according to the stiffness of the thin film, and it conforms to the following formula: The height of the nth mass ring is h n , and the height of the mass ring is the distance from the topmost end to the thin film. The height difference between adjacent mass rings is Δh ω = 2πf n , where C 0 is the speed of sound in air, ω is the angular frequency. When the thin film is square, a is the side length; when the thin film is circular, a is the diameter; when the thin film is of other shapes, a is the equivalent diameter of the thin film. At this time, the equivalent diameter a = 4A / L, A is the area of the thin film, and L is the perimeter of the thin film.

[0015] Preferably, in the technical solution of the present invention, at least four groups of the thin-film acoustic metamaterials are provided inside the housing. The sizes of each group of the thin-film acoustic metamaterials are different from each other. A number of the thin-film acoustic metamaterials are stacked side by side inside each group of the thin-film acoustic metamaterials, and there are gaps between adjacent thin-film acoustic metamaterials; when a number of groups of the thin-film acoustic metamaterials are filled inside the housing, a first through hole penetrating through all the thin-film acoustic metamaterials is provided in the middle of the housing. A first perforation is provided in the middle of each group of the thin-film acoustic metamaterials. A second through hole is also provided at the position of the housing corresponding to the first perforation. The other side of the housing is hermetically provided, and the second through hole is communicated with or coaxial with the first perforation.

[0016] Preferably, in the technical solution of the present invention, the thin-film acoustic metamaterials are arranged along the width or length direction of the housing; when the thin-film acoustic metamaterials are arranged along the width direction of the housing, a first through hole is provided in the middle of the housing, and a notch corresponding to the first through hole is also provided on the thin-film acoustic metamaterial at the position of the first through hole, so that the first through hole penetrates through the interior of the housing to the bottom of the housing. The first perforation of the thin-film acoustic metamaterial is provided at the middle position of each thin-film acoustic metamaterial, and the second through hole is coaxial with the first perforation; when the thin-film acoustic metamaterials are arranged along the length direction of the housing, the first through hole communicates with the gap.

[0017] The sound insulation structure of a multi-chamber sound insulation module based on Helmholtz resonance is composed of the multi-chamber sound insulation module array based on Helmholtz resonance described in any one of the above.

[0018] The beneficial effects of the present invention are as follows:

[0019] The present invention aims to provide a multi-chamber sound insulation module based on Helmholtz resonance. By superimposing and using multi-level thin-film acoustic metamaterials, a multi-chamber resonance structure is formed, and each chamber can effectively absorb noise in a specific frequency band. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings incorporated into the specification and constituting a part of the specification illustrate embodiments of the present invention and are used together with the description to explain the principles of the present invention. In these drawings, like reference numerals are used to represent like elements. The drawings in the following description are some embodiments of the present invention, not all embodiments. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0021] Figure 1 It is a schematic diagram of the overall structure of Embodiment 1 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific embodiment of the present invention;

[0022] Figure 2 It is a schematic diagram of the overall structure of Embodiment 1 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific embodiment of the present invention with the housing removed;

[0023] Figure 3 It is a schematic diagram of the overall structure of a single thin-film acoustic metamaterial of Embodiment 1 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific embodiment of the present invention;

[0024] Figure 4It is a schematic diagram of the overall structure of a single thin-film acoustic metamaterial in Embodiment 1 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention;

[0025] Figure 5 It is a schematic diagram of the overall structure of Embodiment 2 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention;

[0026] Figure 6 It is a schematic diagram of the overall structure of Embodiment 2 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention;

[0027] Figure 7 It is a schematic diagram of the overall structure of Embodiment 2 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention without the outer shell;

[0028] Figure 8 It is a schematic diagram of the overall structure of another implementation manner of Embodiment 1 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention without the outer shell;

[0029] Figure 9 It is a schematic diagram of the overall structure of another implementation manner of Embodiment 2 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention without the outer shell;

[0030] Figure 10 It is a schematic diagram of the overall structure of Embodiment 4 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention;

[0031] Figure 11 is Figure 10 The cross-sectional schematic diagram of BB in;

[0032] Figure 12 It is a schematic diagram of the overall structure of Embodiment 3 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention;

[0033] Figure 13 It is a schematic diagram of the overall structure of Embodiment 5 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention;

[0034] Figure 14 It is a schematic diagram of the overall structure of Embodiment 6 of the multi-chamber sound insulation module based on Helmholtz resonance provided in the specific implementation manner of the present invention;

[0035] In the figure:

[0036] 1. Housing; 11. First through-hole; 12. Second through-hole; 2. Thin-film acoustic metamaterial; 21. First perforation; 22. Central mass block; 23. Mass ring; 231. First mass ring; 232. Second mass ring; 233. Third mass ring; 234. Fourth mass ring; 235. Fifth mass ring; 24. Thin film; 241. First thin film; 242. Second thin film; 243. Third thin film; 25. Notch; 26. Gap. Detailed implementation manners

[0037] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments may be arbitrarily combined with each other.

[0038] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and through specific implementation manners.

[0039] Embodiment 1

[0040] As Figures 1-4 shown in FIGS. 7 and 8, a multi-chamber sound insulation module based on Helmholtz resonance provided by the present invention includes a housing 1. A plurality of thin-film acoustic metamaterials 2 arranged side by side along the width direction of the housing 1 are stacked and filled inside the housing 1. A gap 26 is provided between adjacent thin-film acoustic metamaterials 2. A first through-hole 11 is opened in the middle of one side of the housing 1. A first perforation 21 is opened on each thin-film acoustic metamaterial 2. When a plurality of thin-film acoustic metamaterials 2 are installed inside the housing 1, the first through-hole 11 and the first perforation 21 are both communicated and can be located on the same axis. The other side of the housing 1 where the first through-hole 11 is located is closed. This design realizes effective sound insulation for broadband noise through the stacked use of multiple layers of thin-film acoustic metamaterials 2, while maintaining the characteristics of simple structure and easy manufacturing.

[0041] By opening through-holes and closing the bottom, an acoustic absorption resonance cavity is formed, and a better sound insulation effect is achieved by applying the principle of Helmholtz resonance.

[0042] Alternatively, a plurality of thin-film acoustic metamaterials 2 arranged side by side along the length direction of the housing 1 are stacked and filled inside the housing 1. At this time, the gap 26 is communicated with the first through-hole 11, thereby forming a resonance cavity.

[0043] Specifically, the thin-film acoustic metamaterial 2 includes a central mass block 22, a mass ring 23, and a thin film 24. There are m mass rings 23, where m is a natural number greater than 1. The m mass rings 23 are arranged in sequence from the center outwards. The mass rings 23 are wound around the periphery of the central mass block 22 and are enclosed to form a ring. The material of the thin film 24 can be metal or metal alloy, such as stainless steel or aluminum alloy. The first perforation 21 is opened on the central mass block 22.

[0044] The function of the central mass block 22 is to increase the mass and inertia of the system, thereby improving the sound insulation effect in the low-frequency band. The mass rings 23 are used to adjust the resonance characteristics at different frequencies. By adjusting the number and position of the mass rings 23, effective absorption of noise in different frequency bands can be achieved. The thin film 24, as the main medium for sound wave transmission, the selection of its thickness and material directly affects the sound insulation effect. For example, if a thinner thin film 24 (such as thickness ≤ 0.2 mm) is selected, a better sound insulation effect can be obtained in the high-frequency band; while if a thicker thin film 24 is selected, it is more suitable for the sound insulation requirements in the low-frequency band.

[0045] The mass rings 23 are symmetrically arranged on both sides of the thin film 24, and the central mass block 22 is arranged on one side of the first thin film 24. Such a layout helps to balance the center of gravity of the entire system and reduce vibrations and noises caused by eccentricity.

[0046] The shape of the mass ring 23 can be square, circular, regular hexagon or triangle, and the specific selection depends on the actual application scenario and space limitations.

[0047] The material of the mass ring 23 can be selected from steel, aluminum alloy, carbon fiber or engineering ABS plastic. These materials have their own advantages and disadvantages. For example, steel has high strength but large weight and is suitable for scenarios that need to bear large pressures; aluminum alloy is light and corrosion-resistant and is suitable for outdoor or humid environments; carbon fiber has the advantages of high strength and light weight and is suitable for applications with high performance requirements; engineering ABS plastic has good processing performance and low cost and is suitable for mass production and low-cost applications.

[0048] The outermost mass ring 23 is used to support the entire structure, and the materials of the remaining mass rings 23 can also be made of high specific stiffness materials such as steel, aluminum alloy, carbon fiber or engineering ABS plastic. When steel is selected as the material, it has high strength and stability; when aluminum alloy is selected, it is lighter in weight and convenient for transportation and installation. The shape of the mass ring 23 can be adjusted according to actual needs, and the common ones are square, circular, regular hexagon or triangle.

[0049] By setting the multi - order mass ring 23 and the central mass block 22 structure on the metal thin film 24, the resonance effect in different frequency ranges is achieved, thus forming broadband sound insulation characteristics. At the same time, the use of the metal thin film 24 improves the weather resistance and service life of the product, solving the problem that the traditional non - metal thin film 24 is easily damaged in harsh environments. This design not only improves the sound insulation effect but also extends the service life of the product, and is applicable to various indoor and outdoor environments.

[0050] The material of the thin film 24 can also be diversified. For example, stainless steel has good corrosion resistance and mechanical strength, suitable for long - term use; aluminum alloy is light and has good heat conduction, which helps with heat dissipation and is applicable to high - temperature environments.

[0051] The material of the central mass block 22 is preferably stainless steel because stainless steel not only has good mechanical properties but also strong corrosion resistance and a long service life.

[0052] By the superposition use of multi - layer thin - film acoustic metamaterials 2, a multi - chamber resonance structure is formed, and each chamber can effectively absorb noise in a specific frequency band. At the same time, through the careful design of the materials and structures of each part, the simplification and optimization of the structure are achieved, reducing the manufacturing cost, and improving the reliability and durability of the product. Compared with traditional heavy materials and complex structures, the multi - chamber sound insulation module of the present invention shows obvious advantages in terms of lightweight and compactness, and is particularly suitable for various places that require efficient sound insulation.

[0053] Moreover, the height of the mass ring 23 gradually increases, so as to form a gradient - type resonance structure, enabling sound waves of different frequencies to be effectively absorbed at different levels.

[0054] Definition: The height of the central mass block 22 is h mass , and the mass is M mass , the height of the nth mass ring 23 is h n , and the mass is M frame,n , where the height of the mass ring 23 is the distance from the top to the thin film 24.

[0055] The distance between n adjacent mass rings 23 arranged in sequence from the center outwards is set according to the equivalent diameter between each order of thin films 24, ensuring the synergistic effect between each metamaterial structure, improving the overall sound insulation effect, and ensuring that the vibration of each order is not restricted, and the modal vibration modes between each order will not affect the thin films 24 within other orders. The sound insulation frequency bands between each order are specially designed in a stepped manner, so that the multi - order complement each other to form broadband sound insulation.

[0056] The height of the mass ring 23 of the first - order acoustic metamaterial is h 1 , and the height of the mass ring 23 of the second - order acoustic metamaterial is h 2 , such asFigure 4 As shown, in the direction of the outermost mass ring 23, they are h 2 , h 3 ...h n , and h mass < h 1 < h 2 <…< h n . The height of the central mass block 22 is lower than that of the innermost mass ring 23, ensuring that each mass ring 23 and the central mass block 22 can vibrate independently without interfering with each other, thereby avoiding the change in resonance frequency caused by the height difference and improving the stability and sound insulation effect of each order of the metamaterial structure.

[0057] The natural frequency f of the first-order acoustic metamaterial 1 can be calculated by the formula , where K is the stiffness of the film 24, and M 1 is the equivalent mass of the film 24 of the first-order acoustic metamaterial at the center, and M mass is the mass of the central mass block 22.

[0058] From the second order onwards, the formula for calculating the natural frequency of the nth-order acoustic metamaterial is where Mn is the equivalent mass of the film 24 corresponding to the nth order at the center, and M e,n-1 is the equivalent mass of the (n - 1)th-order acoustic metamaterial.

[0059] That is: the natural frequency f of the second-order acoustic metamaterial 2 can be calculated by the formula , where M e,1 = M 1 + M mass + M frame,1 , and M frame,1 is the mass of the first mass ring 231.

[0060] The natural frequency of the third-order acoustic metamaterial:

[0061] Calculated, where M e,2 = M e,1 + M frame,2 , and M frame,2 is the mass of the second mass ring 232.

[0062] For higher-order metamaterial structures, the natural frequency f n can be calculated by the formula , where M e,n-1 = M e,n-2 + M frame,n。The recurrence relation makes the natural frequency distribution of each level of the metamaterial structure more uniform, avoiding excessive concentration in a single frequency band, thus achieving efficient sound insulation in a wide frequency band. The precise design of the central mass block 22 and each order of the metamaterial structure ensures that each metamaterial structure has a different natural frequency, thus achieving effective sound insulation in multiple frequency bands.

[0063] When the film 24 is square, a is the side length. When the film 24 is circular, a is the diameter. When the film 24 is of other shapes, a is the equivalent diameter of the film 24. At this time, the equivalent diameter a = 4A / L, where A is the area of the film 24 and L is the perimeter of the film 24.

[0064] Calculate the thickness d of the film 24 according to the stiffness K of the film 24, which conforms to the following formula: where E is the Young's modulus and μ is the Poisson's ratio. By precisely controlling these parameters and optimizing the stiffness of the film 24, the sound insulation effect is further improved.

[0065] The height of the nth mass ring 23 is h n , and the height difference between adjacent mass rings 23 is Δh.

[0066] ω = 2πf n ,

[0067] where C 0 is the speed of sound in air and ω is the angular frequency.

[0068] For example, the height difference between the first mass ring 23 and the central mass block 22 is: Δh 1 = h 1 - h mass . The height difference between the second mass ring 23 and the first mass ring 23 is: Δh 2 = h 2 - h 1 . The height difference between the third mass ring 23 and the second mass ring 23 is: Δh 3 = h 3 - h 2 .

[0069] The distance between adjacent mass rings 23 is set according to the equivalent diameter between the corresponding films 24 of each order.

[0070] Through more precise calculations, the compactness and stability of the entire device are maintained, the accuracy of the module is increased, and it is more suitable for practical engineering applications. The height of the mass ring 23 increases layer by layer, which can achieve a resonance effect in different frequency ranges, thus achieving the effect of wide-band sound insulation.

[0071] By gradually increasing the thin film 24 and the mass ring 23, a progressive multi-chamber resonance structure is formed. Each chamber functions at a specific frequency band, and the acoustic metamaterial can thus effectively isolate broadband noise. Especially when facing noise with a mixture of multiple frequencies, the holes penetrate through the interior of the housing 1 to the source at the bottom of the progressive housing 1. This progressive multi-chamber structure of the thin film acoustic metamaterial can better adapt to changes in different frequency bands and achieve a more comprehensive sound insulation acoustic effect compared to a single multi-chamber structure.

[0072] Embodiment 2

[0073] As Figures 5-7 As shown in FIGS. 8 and 9, the difference between this embodiment and Embodiment 1 is that at least four groups of thin film acoustic metamaterials 2 are provided inside the housing 1. The sizes of each group of thin film acoustic metamaterials 2 are different from each other. A plurality of thin film acoustic metamaterials 2 are stacked side by side inside each group of thin film acoustic metamaterials 2, and the outer contour of each group of thin film acoustic metamaterials 2 matches the shape of the inner wall of the housing 1, so that the thin film acoustic metamaterials 2 are filled in the housing 1 without gaps. When a plurality of groups of thin film acoustic metamaterials 2 are filled inside the housing 1, a first through hole 11 penetrating through all the thin film acoustic metamaterials 2 is provided in the middle of the housing 1. A first perforation 21 is provided in the middle of each group of thin film acoustic metamaterials 2, and a second through hole 12 is also provided at the position of the housing 1 corresponding to the first perforation 21. The other side of the housing 1 is closed, and the second through hole 12 communicates or is coaxial with the first perforation 21. For example, when there is enough space for the first through hole 11 or the second through hole 12 to pass through the gap 26, the through hole and the perforation do not need to be coaxial, and can be adjusted by changing the installation angle of the thin film acoustic metamaterial 2.

[0074] By combining and using multiple groups of thin film acoustic metamaterials 2 with different sizes, the sound insulation frequency band is further broadened and the sound insulation effect is improved. Especially when facing a noise source with a mixture of multiple frequencies, this multi-component structure can better adapt to changes in different frequency bands and achieve a more comprehensive sound insulation effect.

[0075] Specifically, the thin film acoustic metamaterials 2 can be arranged along the width direction or the length direction of the housing 1.

[0076] When arranged along the width direction, a first through hole 11 is provided in the middle of the housing 1, and a notch 25 corresponding to the first through hole 11 is also provided on the thin film acoustic metamaterial 2 located at the position of the first through hole 11, so that the first through hole 11 penetrates through the interior of the housing 1 to the bottom of the housing 1. The first perforation 21 of the thin film acoustic metamaterial 2 is provided at the middle position of each thin film acoustic metamaterial 2, and the second through hole 12 is coaxial with the first perforation 21. This can ensure uniform propagation of sound in all directions and avoid poor sound insulation in local areas.

[0077] When arranged along the length direction, the gaps 26 of the adjacent thin-film acoustic metamaterials 2 communicate with the first through-hole 11. The first through-hole 11 is formed in the middle of the housing 1, so that the first through-hole 11 penetrates through the interior of the housing 1 to the bottom of the housing 1.

[0078] When multiple groups of thin-film acoustic metamaterials 2 with different sizes are installed in the housing 1, through the combined use of the first through-hole 11 and the first perforation 21 located on the same axis, a more complex multi-chamber resonance structure is formed. Each chamber can effectively absorb noise in a specific frequency band. The other side of the first through-hole 11 is closedly arranged with the housing 1. This solution achieves the effect of effectively reducing noise. This multi-component structure not only improves the sound insulation effect, but also enhances the reliability of various systems such as building sound insulation walls and industrial noise reduction devices to a certain extent.

[0079] Embodiment 3

[0080] As Figure 12 shown, the difference between this embodiment and the foregoing embodiments is that five mass rings 23 are provided in this embodiment, that is, m = 5, then n = 1, 2, 3, 4, 5.

[0081] As Figure 5 shown in, a central mass block 22 is fixed on the thin film 24 inside the first mass ring 231 to form a first-order acoustic metamaterial;

[0082] The area surrounded by the second mass ring 232 forms a second-order acoustic metamaterial. The area surrounded by the second mass ring 232 here is composed of the second mass ring 232, the first mass ring 231, the central mass block 22, and the thin film 24 in the corresponding surrounding area.

[0083] The area surrounded by the third mass ring 233 forms a third-order acoustic metamaterial. The area surrounded by the third mass ring 233 here is composed of the third mass ring 233, the second mass ring 232, the first mass ring 231, the central mass block 22, and the thin film 24 in the corresponding surrounding area.

[0084] The area surrounded by the fourth mass ring 234 forms a fourth-order acoustic metamaterial. The area surrounded by the fourth mass ring 234 here is composed of the fourth mass ring 234, the third mass ring 233, the second mass ring 232, the first mass ring 231, the central mass block 22, and the thin film 24 in the corresponding surrounding area.

[0085] The region surrounded by the fifth mass ring 235 forms the fifth-order acoustic metamaterial. Here, the region surrounded by the fifth mass ring 235 consists of: the fifth mass ring 235, the fourth mass ring 234, the third mass ring 233, the second mass ring 232, the first mass ring 231, the central mass block 22, and the thin film 24 within the corresponding surrounding region.

[0086] Embodiment 4

[0087] As Figures 10-11 shown, in this embodiment, there are three mass rings, i.e., m = 3, and the number of thin films is also m = 3; then n = 1 or 2 or 3.

[0088] As Figure 3 shown in, the interior of the first mass ring 231 is provided with the first thin film 241, and the central mass block 2 is fixed on the first thin film 241 to form the first-order acoustic metamaterial.

[0089] A second thin film 242 is provided between the second mass ring 232 and the first mass ring 231, and the region surrounded by the second mass ring 232 forms the second-order acoustic metamaterial. Here, the region surrounded by the second mass ring 232 consists of: the second mass ring 232, the second thin film 242, and all the components of the first-order acoustic metamaterial.

[0090] A third thin film 243 is provided between the third mass ring 233 and the second mass ring 232, and the region surrounded by the third mass ring 233 forms the third-order acoustic metamaterial. Here, the region surrounded by the third mass ring 233 consists of: the third mass ring 233, the third thin film 243, and all the components of the second-order acoustic metamaterial.

[0091] Embodiment 5

[0092] As Figure 13 shown, the difference between this embodiment and Embodiment 1 is that the shape of the mass ring 23 is set as a regular hexagon. The regular hexagon design can provide more resonance paths, thereby further expanding the sound insulation frequency band. The regular hexagon design can also improve the stiffness and stability of the structure, reduce deformation and vibration, and can provide more degrees of freedom, enabling different frequency components to propagate on different paths, thus achieving a wider sound insulation effect. The regular hexagon design also helps to improve the stiffness and stability of the structure, reduce deformation and vibration, and is particularly suitable for applications in high-frequency vibration environments.

[0093] Embodiment 6

[0094] This embodiment consists of an array of multi-cavity sound insulation modules based on Helmholtz resonance in Embodiments 1 - 5.

[0095] As Figure 14As shown, when it is a multi - cavity sound insulation module based on Helmholtz resonance in Embodiment 1, it is composed of arrays in two directions along the x - direction and the y - direction. Each module is fixed through appropriate connectors to form an integral sound insulation structure. Such a design can significantly improve the sound insulation effect of a large - area space and is applicable to fields such as building sound insulation and industrial noise control.

[0096] Specifically, the sound insulation modules can be arranged in a predetermined pattern, such as a rectangular array, a honeycomb - like array or an array with other geometric forms. This arrangement method can not only make full use of space but also achieve a wide - band combination to effectively insulate different - frequency noises.

[0097] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. The present invention has only been described in detail with reference to the preferred embodiments. Those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and all should be covered within the scope of the claims of the present invention.

Claims

1. A multi-cavity sound insulation module based on Helmholtz resonance, characterized in that: The invention comprises a shell (1), wherein a plurality of thin film acoustic metamaterials (2) are stacked and filled in the shell (1) and arranged along the width of the shell or the length of the shell, and there is a gap (26) between adjacent thin film acoustic metamaterials (2); a first through hole (11) is opened in the middle of one side of the shell (1), and the rest of the shell (1) is sealed, so as to form a resonance cavity; When the thin film acoustic metamaterials are arranged along the width direction of the shell, each of the thin film acoustic metamaterials (2) is provided with a first through hole (21), and the first through hole (11) is connected to the first through hole (21); When the thin film acoustic metamaterial is arranged along the length direction of the shell, the first through hole (11) is connected to the gap (26).

2. The multi-cavity sound insulation module based on Helmholtz resonance according to claim 1, characterized in that: The thin film acoustic metamaterial (2) comprises a central mass block (22), a mass ring (23) and a thin film (24); the mass ring (23) is provided in m numbers, m being a natural number greater than 1; the m mass rings (23) are arranged in a row from the center to the outside; the mass rings (23) are arranged around the periphery of the central mass block (22) and are closed in a ring shape; the material of the thin film (24) is metal or metal alloy; and the first through hole (21) is provided on the central mass block (22); The first through hole (11) is coaxial with the first through hole (21).

3. The multi-cavity sound insulation module based on Helmholtz resonance according to claim 1, characterized in that: The thin film acoustic metamaterial (2) comprises a central mass block (22), a mass ring (23) and a thin film (24); m of the mass rings (23) are provided, m being a natural number greater than 1, and the m mass rings (23) are arranged one after another from the center to the outside; the mass rings (23) are arranged around the periphery of the central mass block (22) and are closed and arranged in a ring shape; the thin film (24) is made of metal or metal alloy; m of the thin films (24) are provided, and the m thin films (24) are arranged one after another from the center to the outside; the nth mass ring (23) is provided with the nth thin film (24), n being any natural number greater than or equal to 1 and less than or equal to m; the area surrounded by the nth mass ring (23) forms an nth-order acoustic metamaterial; the central mass block (22) is fixed on the first thin film (24); and the first through hole (21) is opened on the central mass block (22); The first through hole (11) is coaxial with the first through hole (21).

4. The multi-cavity sound insulation module based on Helmholtz resonance according to claim 2 or 3, characterized in that: The mass rings (23) are symmetrically arranged on both sides of the membranes (24), and the central mass block (22) is arranged on one side of the first membrane (24); The mass ring (23) gradually increases in height from the center to the outside; The thickness of the film (24) is ≤0.2 mm; The mass ring (23) is in the shape of a square, a circle, a regular hexagon or a triangle.

5. The multi-cavity sound insulation module based on Helmholtz resonance according to claim 2 or 3, characterized in that: The mass ring (23) is made of steel, aluminum alloy, carbon fiber or engineering ABS plastic; The film (24) is made of stainless steel or aluminum alloy; The material of the central mass block (22) is stainless steel.

6. The multi-cavity sound insulation module based on Helmholtz resonance according to claim 3, characterized in that: The thickness and / or material of the n films (24) are different; The number of mass rings (23) is three, and the number of membranes (24) is four.

7. The multi-cavity sound insulation module based on Helmholtz resonance according to claim 2 or 3, characterized in that: The height of the central mass block (22) is h mass , mass is M mass ; The height of the nth mass ring (23) is h n , mass is M frame,n , wherein the height of the mass ring (23) is the distance from the top to the bottom of the mass ring (23); the stiffness of the nth film (24) is K n ; The natural frequency of the nth-order acoustic metamaterial is f n , where the calculation formula of the natural frequency of the first-order acoustic metamaterial is as follows, The calculation formula for the natural frequency of the nth-order acoustic metamaterial is: where Mn is the equivalent mass of the nth film (24) at the center, M e,n-1 is the equivalent mass of the n-1th order acoustic metamaterial; The Young's modulus of the n-th film (24) is E, the thickness is d, and the Poisson's ratio is μ. The thickness of the film (24) is calculated based on the stiffness of the film (24), which conforms to the following formula: The height of the nth mass ring (23) is h n ,, the height of the mass ring (23) is the distance from the top to the film (24), and the height difference between adjacent mass rings (23) is Δh, ω=2πf n , where C0 is the speed of sound in air, ω is the angular frequency, and when the film (24) is a square, a is the side length; When the film (24) is circular, a is the diameter; when the film (24) is in other shapes, a is the equivalent diameter of the film (24), and the equivalent diameter a=4A / L, A is the area of ​​the film (24), and L is the circumference of the film (24).

8. The multi-cavity sound insulation module based on Helmholtz resonance according to claim 1, characterized in that: At least four groups of the thin film acoustic metamaterials (2) are arranged in the housing (1), the sizes of the thin film acoustic metamaterials (2) in each group are different from each other, a plurality of the thin film acoustic metamaterials (2) are stacked in parallel in each group of the thin film acoustic metamaterials (2), and the gaps (26) exist between adjacent thin film acoustic metamaterials (2); When the shell (1) is filled with a plurality of groups of the thin film acoustic metamaterials (2), the middle of the shell (1) is provided with the first through hole (11) penetrating all the thin film acoustic metamaterials (2), the middle of each group of the thin film acoustic metamaterials (2) is provided with the first through hole (21), the shell (1) is also provided with a second through hole (12) at a position corresponding to the first through hole (21), the other side of the shell (1) is closed, and the second through hole (12) is connected to or coaxial with the first through hole (21).

9. The multi-cavity sound insulation module based on Helmholtz resonance according to claim 8, characterized in that: The thin film acoustic metamaterial (2) is arranged along the width or length direction of the housing (1); When the thin film acoustic metamaterial (2) is arranged along the width direction of the shell (1), the first through hole (11) is opened in the middle of the shell (1), and a notch (25) corresponding to the first through hole (11) is also arranged on the thin film acoustic metamaterial (2) located at the position of the first through hole (11), so that the first through hole (11) passes through the interior of the shell (1) to the bottom of the shell (1), the first through hole (21) of the thin film acoustic metamaterial (2) is opened in the middle position of each thin film acoustic metamaterial (2), and the second through hole (12) is coaxial with the first through hole (21); When the thin film acoustic metamaterial (2) is arranged along the length direction of the housing (1), the first through hole (11) is connected to the gap (26).

10. A sound insulation structure of a multi-cavity sound insulation module based on Helmholtz resonance, characterized in that: It is composed of the multi-cavity sound insulation module array based on Helmholtz resonance as described in any one of claims 1 to 9.

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