Film and black hole compound type vibration reduction and sound insulation structure and manufacturing method thereof

Abstract

The invention relates to a thin film and black hole composite vibration reduction and sound insulation structure which comprises a plurality of vibration reduction and sound insulation units arranged in a rectangular array, and each vibration reduction and sound insulation unit comprises a plurality of acoustic black hole unit cells and acoustic metamaterial unit cells. The acoustic black hole unit cell comprises a damping block and a black hole frame, the damping block is arranged on the black hole frame, the black hole frame is composed of a partition frame and an acoustic black hole structure, the partition frame is of a polygonal structure, and a plurality of supporting blocks used for supporting the acoustic black hole structure are arranged on the partition frame. The invention further discloses a manufacturing method of the composite material. According to the invention, the acoustic black hole structure is arranged in the black hole frame, and energy is dissipated by utilizing the tip energy gathering effect of the acoustic black hole and cooperating with the damping block, so that the purpose of vibration reduction of the black hole frame is achieved, and a certain vibration reduction effect is achieved while the unit cell sound insulation performance of the acoustic metamaterial is ensured; according to the structure, noise radiation is effectively reduced through the vibration reduction effect of the acoustic black hole structure and the sound insulation effect of the film vibration reduction structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of noise control technology, in particular to a thin film and black hole composite vibration damping and sound insulation structure and a manufacturing method thereof. BACKGROUND

[0002] In recent years, the acoustic metamaterial unit cell technology based on the local resonance package model has become a research hotspot due to its excellent low-frequency sound insulation performance and thin thickness, but in engineering applications, its performance will be attenuated or even invalid due to factors such as large-size stiffness reduction and vibration environment, which is specifically manifested as a decrease in sound insulation peak value and a narrowing of effective acoustic band gap.

[0003] The main reason is the influence of the frame. In practice, in order to provide necessary fixing constraints for the thin film, a grid frame is used for unit cell segmentation, so the frame also occupies a certain proportion of the area. When excited by sound waves, this part will also vibrate and radiate noise; in addition, when installed in a vibration environment (such as the surface of a vibrating thin plate), the frame of the thin film type acoustic metamaterial unit cell will also cause vibration and be transmitted to the surface of the thin film, greatly reducing the sound insulation performance. SUMMARY

[0004] The purpose of the present application is to provide a thin film and black hole composite vibration damping and sound insulation structure to solve the problem of performance attenuation of the thin film type acoustic metamaterial unit cell due to frame vibration in actual engineering applications.

[0005] To achieve the above purpose, the present application discloses a thin film and black hole composite vibration damping and sound insulation structure, comprising: a plurality of vibration damping and sound insulation units arranged in a rectangular array, the vibration damping and sound insulation unit comprising a plurality of acoustic black hole unit cells and a plurality of acoustic metamaterial unit cells, one acoustic black hole unit cell corresponding to one or more acoustic metamaterial unit cells, the acoustic black hole unit cell and the acoustic metamaterial unit cell being stacked in the following manner: the acoustic black hole unit cell and the acoustic metamaterial unit cell are cross-stacked, or at least one layer of the acoustic black hole unit cell is stacked on at least one layer of the acoustic metamaterial unit cell. The acoustic metamaterial unit cell comprises an additional mass, a thin film and a constraint frame, the thin film being fixedly connected to the constraint frame, the side length of the thin film being a men, the additional mass block is fixedly connected in the middle of the film. The acoustic black hole cell comprises a damping block and a black hole frame, the black hole frame is in a polygonal structure, 2N acoustic black hole structures are arranged on each side of the black hole frame, N is a positive integer; at least one split groove is formed on each side of the black hole frame, and the acoustic black hole structure is arranged above the split groove. The acoustic black hole structure comprises a platform part and an energy dissipation part, the length of the platform part is δ1, the length of the energy dissipation part is L, the platform part and the energy dissipation part are fixedly connected or integrally formed, the platform part has a uniform thickness, and the thickness of the energy dissipation part gradually decreases away from the platform part; the damping block is arranged on the energy dissipation part and used for absorbing vibration energy. Alternatively, the acoustic black hole structure further comprises an extension block, and the extension block is integrally formed at one end of the energy dissipation part away from the platform part. Two adjacent acoustic black hole structures on the same side of the black hole frame form an acoustic black hole group, the energy dissipation parts of the two acoustic black hole structures in the same group are close to each other, or the energy dissipation parts of the two acoustic black hole structures in the same group are connected through the extension block; adjacent acoustic black hole groups share one platform part.

[0006] Preferably, the film is a composite film, the composite film comprises a substrate layer and a coating layer, the coating layer covers at least one side of the substrate layer, the thickness of the substrate layer is δ mem , the value range of δ mem is 0.05-0.15mm, the thickness of the coating layer is δ mem , the value range of δ mem is 0.1-0.3μm.

[0007] Preferably, the coating layer covers two sides of the substrate layer, the substrate layer is a PET film, the thickness δ mem,PET =0.1mm, and the coating layer is an aluminum layer, the thickness δ mem,Al =0.2μm.

[0008] Preferably, the additional mass block is a two-dimensional plate-shaped black hole structure.

[0009] Preferably, adjacent acoustic black hole cells share the side of the black hole frame.

[0010] Preferably, the platform part is in a cuboid shape, one side of the energy dissipation part close to the platform part has a thickness equal to that of the platform part, and the thickness of the energy dissipation part gradually decreases away from the platform part in a function form (x)=Axm(m≥2), wherein x represents a position; the size of the energy dissipation part in the front-rear direction is consistent with that of the platform part, and the damping block is arranged at one end of the energy dissipation part away from the platform part.

[0011] Preferably, on the same side of the black hole framework, there are M acoustic black hole structures with the same structure and 2N-M acoustic black hole structures with different structures, where M is a natural number and 0≤M≤2N.

[0012] Preferably, the damping block is connected to the acoustic black hole structure via adhesive tape.

[0013] Preferably, the damping block is made of rubber, silicone, or polyethylene.

[0014] Preferably, the energy dissipation sections are close to each other, and adjacent acoustic black hole structures share the same damping block. The damping block is disposed above the energy dissipation section or between the two energy dissipation sections.

[0015] A method for fabricating a composite vibration-damping and sound-insulating structure of a thin film and a black hole, comprising the following steps: S1, determining the vibration frequency and the sound insulation frequency; S2, calculating the dimensions of the black hole structure based on the vibration frequency; S3, calculating the unit cell dimensions of the acoustic metamaterial based on the sound insulation frequency; S4, matching design of the black hole structure and the acoustic metamaterial structure.

[0016] Preferably, the calculation of the black hole structure size in step S2 uses the following formula:

[0017] in, The effective frequency of the acoustic black hole structure. 0 represents the uniform thickness of the outer surface of the acoustic black hole structure; L represents the length of the energy dissipation section; E represents the Young's modulus of the material used in the acoustic black hole structure; ρ represents the density of the material used in the acoustic black hole structure. The Poisson's ratio of the material used in the acoustic black hole structure; m is the power exponent of the power function fitted to the acoustic black hole structure. The design of the acoustic black hole structure includes the following steps: a1. Determine the uniform thickness of the outer surface of the acoustic black hole structure. 0. a2. Determine the materials used in the structure of the acoustic black hole, and obtain the Young's modulus E and Poisson's ratio of the materials. 1. Density parameter ρ. 2. Combine the parameters from steps a1 and a2 with the effective frequency of the acoustic black hole structure. ABH Substituting into the formula for calculating the size of a black hole structure, the length L of the energy dissipation section is obtained. a4. By adjusting h(x) = Ax m The length L of the energy dissipation part makes the black hole's operating frequency near the vibrational frequency.

[0018] Preferably, the calculation of the unit cell size of the acoustic metamaterial in step S3 uses the following formula:

[0019] in: The sound insulation frequency is Kmem, the equivalent stiffness of the membrane is Kmem, and the equivalent mass of the membrane at its center is Mmem. mass denoted as ρ, where ρ is the mass of the central mass block; μn is the modal factor of the thin film; and a is the side length of the thin film.

[0020] Preferably, in step S4, the matching design of the black hole structure and the acoustic metamaterial structure includes the following steps: c1, calculating the energy dissipation part length L according to the formula, and taking the maximum value L among the various energy dissipation part lengths L. max Calculate the side length 'a' of the film according to the formula. mem In each film with a side length a mem Take the maximum value a from the middle men，max c2, Compare with L max and a mem。max If a mem,max ≥2nL max Let n be a positive integer. An extension block is set at the end of the energy dissipation section away from the platform section. The extension block is integrally formed with the acoustic black hole structure. The thickness of the extension block is equal to the thickness of the end of the energy dissipation section away from the platform section. The length of the extension block is used to adjust the side length of the black hole frame, so that one acoustic black hole unit cell corresponds to one acoustic metamaterial unit cell. If a mem，max ≤2nL max Where n is a positive integer, adjust the film quality parameters so that na mem，max ≥2nL max or a mem，max ≥2nL max , where n is a positive integer; if na mem，max ≥2nL max By adjusting the side length of the black hole framework through the extension blocks, one acoustic black hole unit cell corresponds to multiple acoustic metamaterial unit cells; if a mem，max ≥2nL max By adjusting the side length of the black hole frame by extending the block, one acoustic black hole unit cell corresponds to one acoustic metamaterial unit cell.

[0021] The present invention has the following beneficial effects: 1. This invention sets up an acoustic black hole structure in a black hole frame, utilizing the energy concentration effect at the tip of the acoustic black hole, and dissipating the energy with a damping block, thereby achieving the purpose of vibration reduction of the black hole frame. While ensuring the sound insulation performance of the acoustic metamaterial unit cell, it also has a certain vibration reduction effect. This structure effectively reduces noise radiation through the vibration reduction of the acoustic black hole structure and the sound insulation effect of the thin film vibration reduction structure.

[0022] 2. The stacking method and quantity of acoustic black hole unit cells and acoustic metamaterial unit cells can be flexibly set according to actual needs, which has a wide range of applications. Attached Figure Description

[0023] Figure 1This is an exploded view of the vibration reduction and sound insulation unit provided in a specific embodiment of the present invention; Figure 2 This is a side view of the vibration reduction and sound insulation unit provided in a specific embodiment of the present invention; Figure 3 This is a side view of the vibration reduction and sound insulation unit provided in a specific embodiment of the present invention; Figure 4 This is a schematic diagram of the acoustic black hole structure provided in a specific embodiment of the present invention; Figure 5 This is a schematic diagram of the overall structure of the vibration reduction and sound insulation unit provided in a specific embodiment of the present invention; Figure 6 This is a schematic diagram of the overall structure of the vibration reduction and sound insulation unit provided in a specific embodiment of the present invention; Figure 7 This is a schematic diagram of the overall structure of the vibration reduction and sound insulation unit provided in a specific embodiment of the present invention; Figure 8 This is a schematic diagram of the overall structure of the vibration reduction and sound insulation unit provided in a specific embodiment of the present invention; Figure 9 This is a schematic diagram of the overall structure provided in a specific embodiment of the present invention; Figure 10 This is a schematic diagram of the structure of multiple acoustic metamaterial unit cells spliced ​​together as provided in a specific embodiment of the present invention; Figure 11 This is a schematic diagram of the structure of the thin film provided in a specific embodiment of the present invention; Figure 12 This is a schematic diagram of the structure of multiple acoustic metamaterial unit cells spliced ​​together as provided in a specific embodiment of the present invention; Figure 13 This is a cross-sectional schematic diagram of AA provided in a specific embodiment of the present invention; Figure 14 This is a top view of the additional mass block provided in a specific embodiment of the present invention; Figure 15 This is a cross-sectional schematic diagram of the additional mass block provided in a specific embodiment of the present invention; Figure 16 This is a schematic diagram of the installation of the vibration reduction and sound insulation structure provided in a specific embodiment of the present invention; Figure 17 This is a schematic diagram of the installation of the vibration reduction and sound insulation structure provided in a specific embodiment of the present invention; Figure 18 This is a test result diagram provided in a specific embodiment of the present invention.

[0024] Explanation of symbols for main components: 1. Damping block; 2. Acoustic black hole structure; 21. Platform section; 22. Energy dissipation section; 23. Extension block; 3. Additional mass block; 4. Thin film; 41. Substrate layer; 42. Coating layer; 5. Constraint frame; 6. Segmentation groove; 7. Structure to be damped. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0026] like Figures 1-18 This invention provides a composite vibration reduction and sound insulation structure of thin film and black hole, such as... Figure 9 It includes: several vibration damping and sound insulation units arranged in a rectangular array, each unit comprising several acoustic black hole unit cells and several acoustic metamaterial unit cells. One acoustic black hole unit cell corresponds to one or more acoustic metamaterial unit cells. The acoustic black hole unit cells and acoustic metamaterial unit cells are stacked in the following manner: acoustic black hole unit cells and acoustic metamaterial unit cells are stacked alternately, or, for example, at least one layer of acoustic black hole unit cells is stacked on at least one layer of acoustic metamaterial unit cells. Figure 7 One layer of acoustic black hole unit cell is stacked on two or more layers of acoustic metamaterial unit cells, or multiple layers of acoustic black hole unit cells are stacked on one layer of acoustic metamaterial unit cell, such as... Figure 8 Alternatively, multiple acoustic structures can be stacked on top of multiple acoustic metamaterial unit cells. The specific setup will be determined based on the site's vibration reduction and sound insulation requirements.

[0027] The acoustic metamaterial unit cell includes an additional mass block 3, a thin film 4, and a constraint frame 5. The thin film 4 is fixedly connected to the constraint frame 5, and the side length of the thin film 4 is a. men The additional mass block 3 is fixedly connected to the middle of the film 4.

[0028] like Figure 11 As shown, film 4 is a composite film, which includes a substrate layer 41 and a coating layer 42. The coating layer 42 covers at least one side of the substrate layer 41, and the thickness of the substrate layer 41 is δ. mem ,δ mem The value range is 0.05-0.15mm, and the thickness of coating layer 42 is δ. mem δ mem The value range is 0.1-0.3 μm. In this embodiment, the coating layer 42 covers both sides of the substrate layer, and the substrate layer 41 is a PET film with a thickness δ. mem,PET =0.1mm, the coating layer is an aluminum layer, and the thickness δ mem,Al =0.2μm. The aluminum layer can reduce the damping factor and flame-retardant properties of non-metallic films.

[0029] The additional mass block 3 is a two-dimensional plate-shaped black hole structure. It is square in shape, thicker at the edges and thinner in the middle, with each cross-section passing through its center exhibiting an acoustic black hole structure. From a top view, the additional mass block 3 has a square outer outline with a circular outline in the center. This circular outline represents the portion where the thickness gradually decreases. This structure can form a localized resonant structure with the composite acoustic metamaterial structure, creating a sound-insulating bandgap that provides sound insulation; simultaneously, it can increase energy consumption during resonance, enhancing sound insulation at the sound insulation valley frequency.

[0030] The acoustic black hole unit cell includes a damping block 1 and a black hole frame. The black hole frame has a polygonal structure; in this embodiment, the black hole frame adopts a square structure. Figure 9 Each side of the black hole framework has 2N acoustic black hole structures 2, where N is a positive integer; each side of the black hole framework has at least one dividing slot, and the acoustic black hole structures 2 are positioned above the dividing slots. In this embodiment, the platform part 21 is integrally formed with the black hole framework, and the energy dissipation part 22 is positioned above the dividing slots. This prevents energy from being conducted from the energy dissipation part 22 to other structures, ensuring the effective accumulation of black hole energy.

[0031] The effective length of the acoustic black hole structure 2 is L. The acoustic black hole structure 2 includes a platform section 21 and an energy dissipation section 22. The length of the platform section 21 is δ1, and the length of the energy dissipation section 22 is L. The platform section 21 and the energy dissipation section 22 are fixedly connected or integrally formed. The platform section 21 has a uniform thickness, and the thickness of the energy dissipation section 22 gradually decreases in the direction away from the platform section 21. A damping block 1 is disposed in the energy dissipation section 22 to absorb vibration energy.

[0032] This invention achieves vibration reduction of the black hole frame by setting an acoustic black hole structure 2 in the black hole frame and utilizing the energy concentration effect of the acoustic black hole tip, combined with the energy dissipation of the damping block 1. While ensuring the sound insulation performance of the acoustic metamaterial unit cell, it also has a certain vibration reduction effect. This structure effectively reduces noise radiation through the vibration reduction of the acoustic black hole structure 2 and the sound insulation effect of the acoustic metamaterial.

[0033] Alternatively, the acoustic black hole structure 2 may also include an extension block 23, which is used to adjust the side length of the black hole frame. The extension block 23 is integrally formed on the end of the energy dissipation section 22 away from the platform section 22. Two adjacent acoustic black hole structures 2 located on the same side of the black hole frame form a group of acoustic black holes. The energy dissipation sections 22 of the two acoustic black hole structures 2 in the same group are close to each other, or the energy dissipation sections 22 of the two acoustic black hole structures 2 in the same group are connected by the extension block 23. Adjacent acoustic black hole groups share a platform section 21, which makes the structure more compact.

[0034] like Figure 9Adjacent acoustic black hole units share the edges of the black hole framework. This effectively reduces the number of acoustic black hole structures 2, preventing mutual interference between adjacent acoustic black hole units. For example, with two side-by-side acoustic black hole structures 2, the energy dissipation sections 22 are tightly pressed together, causing vibrations of different frequencies to propagate within the two acoustic black hole structures 2. This results in energy not being concentrated at the tip of the energy dissipation section 22, reducing vibration reduction and sound insulation performance. Adjacent acoustic black hole structures 2 with their platform sections 21 close to each other share the same platform section 21, which reduces the space occupied by identical structures and improves space utilization efficiency.

[0035] The platform section 21 is rectangular in shape, and the energy dissipation section 22 has the same thickness as the platform section 21 on the side closest to the platform section 21. The thickness of the energy dissipation section 22 increases in a functional manner in the direction away from the platform section 21. (x)=Ax m (m≥2) gradually decreases, where x represents the position; the front-to-back dimensions of the energy dissipation section 22 are consistent with those of the platform section 21, and the damping block 1 is disposed at the end of the energy dissipation section 22 away from the platform section 21. The damping block 1 is connected to the acoustic black hole structure 2 by adhesive tape. Alternatively, the damping block 1 can be connected to the acoustic black hole structure 2 by other flexible connection methods. The damping block 1 is made of rubber, silicone, or polyethylene. Installing and fixing a large shared damping block 1 is generally simpler and faster than precisely installing multiple small independent damping blocks 1, which helps to reduce production costs and improve consistency. In this embodiment, the energy dissipation sections 22 are close to each other, and adjacent acoustic black hole structures 2 share the same damping block 1. The damping block 1 is disposed above the energy dissipation section 22 or between two energy dissipation sections 22.

[0036] On the same edge of the black hole framework, there are M acoustic black hole structures 2 with the same structure, and 2N-M acoustic black hole structures 2 with different structures, where M is a natural number and 0 ≤ M ≤ 2N. That is, different acoustic black holes use different lengths L and different structures within the function... (x)=Ax m Different parameters are used in (m≥2) to achieve vibration energy absorption at multiple frequencies. When there are many vibrations at a certain frequency, the number of acoustic black hole structures 2 absorbing that vibration frequency can be set to be larger.

[0037] A method for fabricating a thin-film and black hole composite vibration damping and sound insulation structure, comprising the following steps: S1. Determine the vibration frequency and sound insulation frequency. S2. Calculate the black hole structure dimensions based on the vibration frequency. S3. Calculate the unit cell dimensions of the acoustic metamaterial based on the sound insulation frequency. S4. Matching design of the black hole structure and the acoustic metamaterial structure.

[0038] The calculation of the black hole structure size in step S2 uses the following formula:

[0039] in, The effective frequency of the acoustic black hole structure. 0 represents the uniform thickness of the outer surface of the acoustic black hole structure; L represents the length of the energy dissipation section; E represents the Young's modulus of the material used in the acoustic black hole structure; ρ represents the density of the material used in the acoustic black hole structure. is the Poisson's ratio of the material used in the acoustic black hole structure; m is the power exponent of the power function fitted to the acoustic black hole structure.

[0040] The design of an acoustic black hole structure includes the following steps: a1. Determine the uniform thickness of the outer surface of the acoustic black hole structure. 0. a2. Determine the materials used in the structure of the acoustic black hole, and obtain the Young's modulus E and Poisson's ratio of the materials. 1. Density parameter ρ. 2. Combine the parameters from steps a1 and a2 with the effective frequency of the acoustic black hole structure. ABH Substituting into the formula for calculating the size of a black hole structure, the length L of the energy dissipation section is obtained. a4. By adjusting h(x) = Ax m The effective length L ensures that the black hole's operating frequency is near the vibrational frequency.

[0041] The calculation of the unit cell size of the acoustic metamaterial in step S3 uses the following formula:

[0042] in: K is the sound insulation frequency. mem M represents the equivalent stiffness of the thin film. mem M represents the equivalent mass of the film at its center; mass denoted as the mass of the central mass block; μn is the mode factor of the thin film; and a is the edge length of the thin film.

[0043] In step S4, the matching design of the black hole structure and the acoustic metamaterial structure includes the following steps: c1. Calculate the length L of the energy dissipation section according to the formula, and take the maximum value L among all the lengths of the energy dissipation section. max Calculate the side length 'a' of the film according to the formula. mem In each film with a side length a mem Take the maximum value a from the middle men，max .

[0044] c2, in contrast to L max and a mem If a mem，max ≥2nL maxn is a positive integer. An extension block is set at the end of the energy dissipation section away from the platform section. The extension block is integrally formed with the acoustic black hole structure. The thickness of the extension block is equal to the thickness of the end of the energy dissipation section away from the platform section. The length of the extension block is used to adjust the side length of the black hole frame so that one acoustic black hole unit cell corresponds to one acoustic metamaterial unit cell.

[0045] If a mem，max ≤2nL max Where n is a positive integer, adjust the film quality parameters so that na mem，max ≥2nL max or a mem，max ≥2nL max n is a positive integer; Ruona mem，max ≥2nL max By adjusting the side length of the black hole frame by extending the block, one acoustic black hole unit cell corresponds to multiple acoustic metamaterial unit cells. If a mem，max ≥2nL max By adjusting the side length of the black hole frame by extending the block, one acoustic black hole unit cell corresponds to one acoustic metamaterial unit cell.

[0046] Taking a vibration frequency of 350Hz and a sound insulation frequency of 350Hz as an example: Acoustic black hole structure design: First, assuming a thickness design, the black hole structure has h0 = 0.01m, f ABH =350Hz, made of ABS material, incorporating Young's modulus E ABS =2×10 9 Pa, Poisson's ratio ν ABS =0.38, density parameter ρ ABS =1200kg / m 3 .

[0047] By adjusting h(x) = Ax m With an effective length L, the black hole's operating frequency is around 350 Hz. After adjustment, A=1, m=2, L=0.1m, f ABH =356Hz. The calculation process is as follows:

[0048] Acoustic Metamaterial Design: Reverse Design of Acoustic Metamaterial Unit Cell Side Length 'a' Based on Peak Sound Insulation Frequency of 350Hz mem =4cm, composite film thickness δ mem =0.1mm, side length a of the additional mass block mass =1cm, thickness of the additional mass block δ mass =1mm.

[0049] Acoustic black hole structure and acoustic metamaterial structure matching design: 2L=20cm>4cm, according to the above design method, a mem ≤2nL(n=1,2,3 When a single cell of an acoustic black hole is required, it must correspond to a multi-cell (5x5) acoustic metamaterial structure. By adjusting the length of the extended thickness l = 2.4 cm and the width δ1 of the uniform thickness portion, the following can be achieved: 2×(δ1+L)+l=6×δ1+5×a like Figure 18 To verify the effectiveness of this invention, simulation tests were conducted. The simulation test results show that: (1) When the frame is not subjected to vibration excitation, the acoustic metamaterial has high sound insulation performance in a certain frequency range around 354Hz; (2) During the test, a single frequency point excitation of 350Hz was added to the edge of the frame. At this time, the sound insulation in the range of 300~400Hz dropped significantly to less than 35dB. The sound insulation in the band gap was basically ineffective due to the vibration of the frame.

[0050] (3) When an acoustic black hole is added, the impact of the increased vibration excitation of the frame on the sound insulation of the acoustic metamaterial is reduced, which basically ensures the effective function of the band gap of the acoustic metamaterial.

[0051] (4) The results show that using the black hole structure as a framework component of the acoustic metamaterial can improve the problems of bandgap failure and deterioration of sound insulation performance of the acoustic metamaterial under vibration environment, and meet the requirements of engineering use.

[0052] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A composite vibration reduction and sound insulation structure of a thin film and a black hole, characterized in that, include: A plurality of vibration damping and sound insulation units are arranged in a rectangular array. Each vibration damping and sound insulation unit includes a plurality of acoustic black hole unit cells and a plurality of acoustic metamaterial unit cells. One acoustic black hole unit cell corresponds to one or more acoustic metamaterial unit cells. The acoustic black hole unit cells and acoustic metamaterial unit cells are stacked in the following manner: the acoustic black hole unit cells and acoustic metamaterial unit cells are stacked in an alternating manner, or at least one layer of acoustic black hole unit cells is stacked on at least one layer of acoustic metamaterial unit cells. The acoustic metamaterial unit cell includes an additional mass block (3), a thin film (4), and a constraint frame (5). The thin film (4) is fixedly connected to the constraint frame (5), and the side length of the thin film (4) is a. men The additional mass block (3) is fixedly connected to the middle of the film (4); The acoustic black hole unit cell includes a damping block (1) and a black hole frame. The black hole frame has a polygonal structure. Each side of the black hole frame is provided with 2N acoustic black hole structures (2), where N is a positive integer. Each side of the black hole frame is provided with at least one dividing slot (6), and the acoustic black hole structure (2) is located above the dividing slot (6). The acoustic black hole structure (2) includes a platform section (21) and an energy dissipation section (22). The length of the platform section (21) is δ1, and the length of the energy dissipation section (22) is L. The platform section (21) and the energy dissipation section (22) are fixedly connected or integrally formed. The platform section (21) has a uniform thickness, and the thickness of the energy dissipation section (22) gradually decreases in the direction away from the platform section (21). The damping block (1) is disposed in the energy dissipation section (22) to absorb vibration energy. Alternatively, the acoustic black hole structure (2) may further include an extension block (23), which is integrally formed at the end of the energy dissipation section (22) away from the platform section (22); Two adjacent acoustic black hole structures (2) located on the same side of the black hole frame form an acoustic black hole group. The energy dissipation parts (22) of the two acoustic black hole structures (2) in the same group are close to each other, or the energy dissipation parts (22) of the two acoustic black hole structures (2) in the same group are connected by an extension block (23); adjacent acoustic black hole groups share a platform part (21).

2. The composite vibration reduction and sound insulation structure of thin film and black hole according to claim 1, characterized in that: The film (4) is a composite film, comprising a substrate layer and a coating layer, wherein the coating layer covers at least one side of the substrate layer, and the thickness of the substrate layer is δ. mem ,δ mem The value range is 0.05-0.15 mm, and the thickness of the coating layer is δ. mem δ mem The value range is 0.1-0.3μm.

3. The composite vibration reduction and sound insulation structure of a thin film and a black hole according to claim 2, characterized in that: The coating layer covers both sides of the substrate layer, which is a PET film with a thickness of δ. mem,PET =0.1mm, the coating layer is an aluminum layer with a thickness δ mem,Al =0.2μm.

4. The composite vibration reduction and sound insulation structure of thin film and black hole according to claim 1, characterized in that: The additional mass block (3) is a two-dimensional plate-shaped black hole structure; Adjacent acoustic black hole units share the edges of the black hole framework.

5. The composite vibration reduction and sound insulation structure of a thin film and a black hole according to claim 1, characterized in that: The platform section (21) is rectangular parallelepiped in shape. The energy dissipation section (22) has the same thickness as the platform section (21) on the side closest to the platform section (21). The thickness of the energy dissipation section (22) increases in a functional form in the direction away from the platform section (21). (x)=Ax m (m≥2) gradually decreases, where x represents the position; the front and rear dimensions of the energy dissipation part (22) are consistent with those of the platform part (21), and the damping block (1) is located at the end of the energy dissipation part (22) away from the platform part (21); On the same side of the black hole framework, there are M acoustic black hole structures (2) with the same structure, and 2N-M acoustic black hole structures (2) with different structures, where M is a natural number and 0≤M≤2N.

6. The composite vibration reduction and sound insulation structure of a thin film and a black hole according to claim 1, characterized in that: The damping block (1) is connected to the acoustic black hole structure (2) by adhesive tape; The damping block (1) is made of rubber, silicone or polyethylene; The energy dissipation sections (22) are close to each other and the adjacent acoustic black hole structures (2) share the same damping block (1). The damping block (1) is located above the energy dissipation section (22) or between the two energy dissipation sections (22).

7. A method for fabricating a thin-film and black hole composite vibration-damping and sound-insulating structure, used to fabricate the thin-film and black hole composite vibration-damping and sound-insulating structure according to any one of claims 1-6, characterized in that, Includes the following steps: S1. Determine the vibration frequency and sound insulation frequency; S2. Calculate the size of the black hole structure based on the vibration frequency; S3. Calculate the unit cell size of the acoustic metamaterial based on the sound insulation frequency; S4, matching design of black hole structure and acoustic metamaterial structure.

8. The method for fabricating a thin film and black hole composite vibration reduction and sound insulation structure according to claim 7, characterized in that: The calculation of the black hole structure size in step S2 uses the following formula: in, The effective frequency of the acoustic black hole structure. 0 represents the uniform thickness of the outer surface of the acoustic black hole structure (2); L represents the length of the energy dissipation part (23); E represents the Young's modulus of the material used in the acoustic black hole structure (2); and ρ represents the density of the material used in the acoustic black hole structure (2). is the Poisson's ratio of the material used in the acoustic black hole structure (2); m is the power exponent of the power function fitted to the acoustic black hole structure; The design of an acoustic black hole structure includes the following steps: a1. Proposed acoustic black hole structure (2) External uniform thickness 0; a2. Determine the materials used in the acoustic black hole structure (2), and obtain the Young's modulus E and Poisson's ratio of the materials. Density parameter ρ; a3. Combine the parameters from steps a1 and a2 with the effective frequency of the acoustic black hole structure. ABH Substituting the formula for calculating the size of a black hole structure, we obtain the length L of the energy dissipation part (23); a4. By adjusting h(x) = Ax m The length L of the energy dissipation part (23) makes the black hole's operating frequency near the vibration frequency.

9. The method for fabricating a thin film and black hole composite vibration reduction and sound insulation structure according to claim 8, characterized in that: The calculation of the unit cell size of the acoustic metamaterial in step S3 uses the following formula: in: K is the sound insulation frequency. mem M is the equivalent stiffness of the thin film (4); mem M is the equivalent mass of the film (4) at the center; mass is the mass of the central mass block; μn is the modal factor of the thin film (4); a is the side length of the thin film (4).

10. The method for fabricating a thin film and black hole composite vibration reduction and sound insulation structure according to claim 9, characterized in that: In step S4, the matching design of the black hole structure and the acoustic metamaterial structure includes the following steps: c1. Calculate the length L of the energy dissipation section (23) according to the formula, and take the maximum value L among the lengths of each energy dissipation section (23). max Calculate the side length 'a' of the film according to the formula. mem In each film with a side length a mem Take the maximum value a from the middle men，max ; c2, Comparison with L max and a mem，max If a mem，max ≥2nL max n is a positive integer. An extension block (23) is set at the end of the energy dissipation part (22) away from the platform part (21). The extension block (23) is integrally formed with the acoustic black hole structure (2). The thickness of the extension block (23) is equal to the thickness of the end of the energy dissipation part (22) away from the platform part (21). The length of the extension block (23) is used to adjust the side length of the black hole frame so that one acoustic black hole unit cell corresponds to one acoustic metamaterial unit cell. If a mem，max ≤2nL max Where n is a positive integer, adjust the film quality parameters so that na mem。max ≥2nL max or a mem，max ≥2nL max , where n is a positive integer; if na mem，max ≥2nL max By adjusting the side length of the black hole frame through the extension block (23), one acoustic black hole unit cell corresponds to multiple acoustic metamaterial unit cells; if a mem，max ≥2nL max By adjusting the side length of the black hole frame through the extension block (23), one acoustic black hole unit cell corresponds to one acoustic metamaterial unit cell.

Images