Two-dimensional spiral acoustic black hole structure

Abstract

The invention relates to the technical field of vibration and noise reduction, in particular to a two-dimensional spiral acoustic black hole structure which comprises a two-dimensional acoustic black hole configuration I and / or a two-dimensional acoustic black hole configuration II, the two-dimensional acoustic black hole configuration I is formed by rotating a one-dimensional spiral acoustic black hole structure around the long edge of a base of the one-dimensional spiral acoustic black hole structure, and the two-dimensional acoustic black hole configuration II is formed by rotating the one-dimensional spiral acoustic black hole structure around the long edge of the base of the one-dimensional spiral acoustic black hole structure. And the two-dimensional acoustic black hole configuration II is formed by rotating a one-dimensional spiral acoustic black hole structure around the short edge of the base of the one-dimensional spiral acoustic black hole structure. According to the two-dimensional spiral acoustic black hole structure provided by the invention, a one-dimensional spiral acoustic black hole is widened to a two-dimensional spiral acoustic black hole, so that more degrees of freedom are provided, a wave transmission path is allowed to be adjusted more flexibly, and the wave energy capturing capability of the two-dimensional spiral acoustic black hole structure is enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of vibration reduction and noise reduction, and in particular to a two-dimensional spiral acoustic black hole structure. Background Art

[0002] With the continuous development of modern industry, the vibration problem of equipment is becoming more and more serious. Vibration not only affects the performance and service life of equipment, but also causes noise pollution and even safety hazards. Therefore, the development of vibration reduction technology is of great significance in improving safety, extending equipment life, improving comfort and protecting the environment. Traditional vibration reduction methods usually rely on damping materials, vibration absorbers and vibration isolation systems. These methods not only change the vibration characteristics, but also have performance limitations in certain frequency bands or complex vibration environments.

[0003] As a new type of acoustic vibration reduction structure, the acoustic black hole (ABH) has attracted widespread attention in the field of vibration control in recent years due to its advantages such as small mass, low-frequency vibration reduction, and wide frequency band. Its principle is mainly to change the phase velocity and group velocity of the bending wave propagating in the structure by changing the internal impedance of the structure, so that the bending wave is annihilated in the structure as much as possible. In theory, when the thickness gradually decreases to 0, the wave velocity can be reduced to 0, and no reflection will occur. However, the cutoff frequency and vibration reduction effect of the acoustic black hole are closely related to its length, that is, the longer the length, the lower the cutoff frequency will be, and the better the vibration reduction effect will be. However, an acoustic black hole that is too long not only has low space utilization, but is also difficult to arrange. Therefore, some scholars have proposed to curl it into a spiral acoustic black hole based on the Archimedean spiral, which can greatly ensure space utilization while achieving low-frequency and broadband vibration reduction.

[0004] However, the vibration reduction effect of the existing additional one-dimensional spiral acoustic black hole structure is often affected by the directional arrangement. Different arrangement directions will have different vibration reduction effects. This is because the vibration reduction effect mainly depends on the propagation of waves along a specific direction. In actual production life, the optimal arrangement direction is usually difficult to determine. It is greatly affected by the vibration source and the direction of wave conduction, and has a strong directional dependence. In addition, the one-dimensional spiral acoustic black hole has poor effect at lower frequencies. The vibration frequency of many mechanical systems is usually kept in a lower frequency band, which results in its insignificant vibration reduction effect. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a two-dimensional acoustic black hole structure based on the one-dimensional spiral acoustic black hole, which can retain the advantages of the one-dimensional spiral acoustic black hole while significantly enhancing its directional independence, and can further enhance the vibration reduction effect of the acoustic black hole and provide more flexible adjustment capabilities.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme:

[0007] A two-dimensional spiral acoustic black hole structure, the two-dimensional spiral acoustic black hole structure comprising a two-dimensional acoustic black hole configuration I and / or a two-dimensional acoustic black hole configuration II, the two-dimensional acoustic black hole configuration I being formed by a one-dimensional spiral acoustic black hole structure rotating around the long side of its base, the two-dimensional acoustic black hole configuration II being formed by a one-dimensional spiral acoustic black hole structure rotating around the short side of its base; the one-dimensional spiral acoustic black hole structure comprising a spiral curling portion and a base, the spiral curling portion comprising an extended enhanced thickness portion, a damping portion and a one-dimensional acoustic black hole plate with a gradient thickness The damping part is tightly arranged on the inner circle wall of the extended enhanced thickness part, and the inner end of the damping part is flush with the inner end of the extended enhanced thickness part; the outer end of the extended enhanced thickness part is connected to the end of the base, and the one-dimensional acoustic black hole slab is tightly arranged on the inner circle wall of the extended enhanced thickness part between the outer end of the damping part and the end of the base, the thicker end of the one-dimensional acoustic black hole slab is connected to the end of the base, and the thinner end of the one-dimensional acoustic black hole slab is connected to the damping part.

[0008] As a further optimization scheme of the present invention, the rotation angle of the one-dimensional spiral acoustic black hole structure around the long side or short side of its base is 360°.

[0009] As a further optimization scheme of the present invention, the lower surface of the one-dimensional acoustic black hole slab is a plane and is in close contact with the inner ring wall of the extended enhanced thickness portion, and the upper surface of the one-dimensional acoustic black hole slab is a wedge surface.

[0010] As a further optimization solution of the present invention, the thinner end of the one-dimensional acoustic black hole slab is sandwiched between the extended enhanced thickness portion and the damping portion.

[0011] As a further optimization scheme of the present invention, when the one-dimensional acoustic black hole slab is fully expanded, the sum of the thickness of the one-dimensional acoustic black hole slab and the corresponding extended enhanced thickness portion below is h (x) The expression is:

[0012] h (x) =H t +εx m ;

[0013] Among them, H t is the thickness of the extended enhanced thickness portion; x is the abscissa; m is a constant, and m≥2; ε is the thickness coefficient used to scale the ABH.

[0014] As a further optimization solution of the present invention, the spirally curled portion is formed by an extended enhanced thickness portion, a damping portion and a one-dimensional acoustic black hole slab, which are spirally curled in the form of a standard Archimedean spiral.

[0015] As a further optimization solution of the present invention, the widths of the extended enhanced thickness portion, the damping portion and the one-dimensional acoustic black hole slab are all the same.

[0016] As a further optimization solution of the present invention, the thickness of the damping portion should be greater than twice the thickness of the extended enhanced thickness portion.

[0017] As a further optimization solution of the present invention, the extended enhanced thickness portion and the damping portion are both strip structures with constant thickness.

[0018] As a further optimization scheme of the present invention, the extended enhanced thickness portion and the one-dimensional acoustic black hole slat are made of steel. The base is made of steel. The extended enhanced thickness portion, the one-dimensional acoustic black hole slat and the base are an integrated structure.

[0019] As a further optimization solution of the present invention, the material of the damping part is asphalt.

[0020] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0021] 1. The two-dimensional spiral acoustic black hole structure proposed in the present invention expands the one-dimensional spiral acoustic black hole to a two-dimensional spiral acoustic black hole, provides more degrees of freedom, allows more flexible adjustment of the wave transmission path, and enhances its ability to capture wave energy.

[0022] 2. In order to obtain better effects, previous acoustic black holes have strict requirements on the layout direction. Different directions will have different vibration reduction effects. The two-dimensional spiral acoustic black hole structure proposed in the present invention can significantly improve its directional independence and effectively control the propagation of waves in multiple directions, so there is no need to consider the layout direction, which greatly reduces the impact of directionality on its performance and achieves a wider range of applications.

[0023] 3. The present invention combines the advantages of the spiral acoustic black hole structure, such as lightweight, easy installation and low space occupancy, while further improving its low-frequency and broadband vibration reduction performance, achieving a better vibration suppression effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the structure of the one-dimensional spiral acoustic black hole structure disclosed in an embodiment of the present invention when it is fully expanded.

[0025] Figure 2This is a schematic diagram of a planar one-dimensional spiral acoustic black hole formed by the one-dimensional lath-shaped acoustic black hole rotating inward in the form of an Archimedean spiral in the present invention.

[0026] Figure 3 It is a schematic diagram of the planar one-dimensional spiral acoustic black hole of the present invention rotating 360° around the long side of its base.

[0027] Figure 4 This is a front view of a two-dimensional spiral acoustic black hole structure obtained by rotating the planar one-dimensional spiral acoustic black hole of the present invention around the long side of its base by 360°, denoted as 2D SABH 1.

[0028] Figure 5 Schematic diagram of the cross section of the 2D SABH 1 obtained by rotating the planar one-dimensional spiral acoustic black hole of the present invention 360° around the long side of its base.

[0029] Figure 6 Schematic diagram of the planar one-dimensional spiral acoustic black hole of the present invention rotating 360° around the short side of its base

[0030] Figure 7 This is a front view of a two-dimensional spiral acoustic black hole structure obtained by rotating the planar one-dimensional spiral acoustic black hole of the present invention around the short side of its base by 360°, denoted as 2D SABH 2.

[0031] Figure 8 The schematic cross-sectional view of the 2D SABH 2 obtained by rotating the planar one-dimensional spiral acoustic black hole of the present invention 360° around the short side of its base.

[0032] Fig. 9 This is a schematic diagram of the two-dimensional spiral acoustic black hole of the present invention being installed on a flat plate.

[0033] Fig.10 The diagram is a comparison of vibration characteristics of a flat plate with no vibration reduction element installed, a mass block of equal mass installed, a one-dimensional spiral acoustic black hole of equal mass installed, and a two-dimensional acoustic black hole configuration I of the present invention installed.

[0034] Fig.11 The diagram is a comparison of vibration characteristics of a flat plate with no vibration reduction element installed, a mass block of equal mass installed, a one-dimensional spiral acoustic black hole of equal mass installed, and a two-dimensional acoustic black hole structure II of the present invention installed.

[0035] Figure numerals: 1. two-dimensional spiral acoustic black hole structure; 2. one-dimensional spiral acoustic black hole structure; 21. spiral curled part; 211. extended enhanced thickness part; 212. damping part; 213. one-dimensional acoustic black hole slat; 214. upper surface; 215. lower surface; 22. base; 221. long side; 222. short side; 3. flat plate. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the technical solution of the present invention, the preferred implementation scheme of the present invention is described below in conjunction with specific embodiments. However, it should be understood that the drawings are only used for exemplary description and cannot be understood as a limitation on this patent. In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted. The positional relationship described in the drawings is only for exemplary description and cannot be understood as a limitation on this patent.

[0037] One of the purposes of the present invention is to provide a novel two-dimensional acoustic black hole structure while enhancing the directional independence of the acoustic black hole and further improving the vibration reduction performance, which can solve the vibration and noise reduction problems of the structure at low frequencies and wide frequencies.

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] like Figure 1-8 As shown, the present invention provides two forms of two-dimensional spiral acoustic black hole structures 1, including two-dimensional acoustic black hole configuration I and two-dimensional acoustic black hole configuration II, which are formed by rotating a planar one-dimensional spiral acoustic black hole structure 2 around the long side 221 or short side 222 of its base 22. The one-dimensional spiral acoustic black hole structure 2 is a spiral acoustic black hole structure with enhanced thickness, including a spiral curled portion 21 and a base 22. The damping part 212 is tightly arranged on the inner circle wall of the extended enhanced thickness part 211, and the inner end of the damping part 212 is flush with the inner end of the extended enhanced thickness part 211; the outer end of the extended enhanced thickness part 211 is connected to the end of the base 22, and a one-dimensional acoustic black hole slat 213 is tightly arranged on the inner circle wall of the extended enhanced thickness part 211 between the outer end of the damping part 212 and the end of the base 22, the thicker end of the one-dimensional acoustic black hole slat 213 is connected to the end of the base 22, and the thinner end of the one-dimensional acoustic black hole slat 213 is connected to the damping part 212.

[0040] The spiral curling part 21 is formed by an extended enhanced thickness part 211, a damping part 212 and a one-dimensional acoustic black hole slat 213, and is formed by curling the spiral in the form of a standard Archimedean spiral line, and is used to absorb and dissipate the vibration energy at any position of the structure to be damped while greatly saving the space occupancy. The extended enhanced thickness part 211 is considered to have a certain truncation thickness of the acoustic black hole, and the truncation thickness is extended to a certain length, which can better enhance the acoustic black hole effect; the damping part 212 is set on the inner wall surface of the one-dimensional acoustic black hole slat 213, and is used to absorb the vibration energy gathered at the tip of the one-dimensional acoustic black hole slat 213. The loss factor of the damping part 212 should be selected as large as possible.

[0041] The lower surface 215 of the one-dimensional acoustic black hole slat 213 is a plane and is in close contact with the inner wall of the extended enhanced thickness portion 211, and the upper surface 214 of the one-dimensional acoustic black hole slat 213 is a wedge surface. The upper surface 214 rotates inwardly with the lower surface 215 while maintaining a relative distance from the lower surface 215 to form a spiral acoustic black hole structure. The distance between the plane and the wedge surface is the thickness of the one-dimensional acoustic black hole slat 213. When the one-dimensional acoustic black hole slat 213 is fully unfolded, its thickness decreases exponentially from the thicker end to the thinner end; and the thickest end of the one-dimensional acoustic black hole slat 213 is the outer end of the spiral curling portion 21, which is used to connect with the base 22. The thinner end of the one-dimensional acoustic black hole slab 213 is sandwiched between the extended enhanced thickness portion 211 and the damping portion 212, so that the damping portion 212 is arranged on the tip surface of the one-dimensional acoustic black hole slab 213 to consume the energy gathered at the tip.

[0042] When the one-dimensional acoustic black hole slab 213 is fully expanded, the sum of the thickness of the one-dimensional acoustic black hole slab 213 and the corresponding extended enhanced thickness portion 211 below is h (x) The expression is:

[0043] h(x)=H t +εx m ;

[0044] Among them, H t is the thickness of the extended enhanced thickness portion; x is the abscissa; m is a constant, and m≥2; ε is the thickness coefficient used to scale the ABH.

[0045] The vibration reduction effects of two single two-dimensional acoustic black hole structures are explained below in combination with simulation results.

[0046] In the spiral acoustic black hole structure with enhanced thickness, the extended enhanced thickness part, the one-dimensional acoustic black hole slats and the base can be made of steel or other materials; the extended enhanced thickness part should not be too thick; the thickness of the damping part should be greater than twice the extended enhanced thickness part, and the loss factor should be as large as possible, and the damping part and the acoustic black hole are glued.

[0047] The size of the above-mentioned planar one-dimensional spiral acoustic black hole structure 2 can be changed according to actual conditions, and the number of two-dimensional spiral acoustic black hole structures 1 installed on the structure to be damped can also be appropriately changed. This demonstration configuration is just a special case.

[0048] The present invention will provide a set of parameters and material parameters of a planar one-dimensional spiral acoustic black hole structure 1, which is rotated 360° around the long side and the short side of the base respectively, to obtain two two-dimensional acoustic black hole configurations, denoted as 2D SABH 1 and 2D SABH 2, which are installed on a flat plate of common size to reflect the significant vibration reduction effect of the present invention in planar structures, thereby verifying the beneficial effects of the present invention, including the following contents:

[0049] According to the parametric equation of the Archimedean spiral, the coordinate of the spiral baseline is x b ,y b for:

[0050]

[0051] The baseline length can be integrated to obtain:

[0052]

[0053] The arc length l(θ) and the one-dimensional acoustic black hole expression h(x) = Ht + εx m By combining them, the planar one-dimensional acoustic black hole can be constructed, and then by rotating around the edge, the two-dimensional acoustic black hole structure can be obtained.

[0054] (1) When h(x) = Ht + εx m In the example, the reinforcement thickness Ht is 1 mm, m is 2.2, and ε is 0.015.

[0055] (2) The base 22 has a length of 30 mm and a thickness of 3 mm.

[0056] (3) The length of the one-dimensional acoustic black hole slab 213 is 414.7 mm.

[0057] (4) The length of the extended reinforced thickness portion 211 is 557.2 mm and the width is 30 mm.

[0058] (5) The length of the damping part 212 is 326.4 mm, the thickness is 2 mm, and the material used is asphalt damping.

[0059] (6) The size of the flat plate 3 is 1000 mm × 1000 mm and the thickness is 5 mm.

[0060] Table 1 Material parameters of each material

[0061] Material <![CDATA[Density / kg / m 3 > Elastic modulus / Pa Poisson's ratio Loss Factor steel 7850 <![CDATA[2.1×10 11 ]]> 0.3 0.0026 Asphalt damping 1650 <![CDATA[2.25×10 8 ]]> 0.3 0.8

[0062] (7) The mass of the two-dimensional acoustic black hole configuration I (2D SABH 1) in this paper is 0.909 kg, and the mass of the two-dimensional acoustic black hole configuration II (2D SABH 2) is 1.197 kg.

[0063] (8) Apply the multi-physics field coupling analysis software COMSOL Multiphysics to describe the acoustic black hole structure model.

[0064] (9) The vibration characteristics of the structure are evaluated using the mean square velocity (MQV) formula:

[0065]

[0066] Where v is the vibration velocity amplitude, which can be directly calculated from the solid mechanics section, and v0 is the reference velocity amplitude, which is 1×10 -9 , S is the area of ​​the vibration surface to be monitored.

[0067] Fig. 9 The 2D SABH 1 is installed at the center of the plate, and the point excitation is located directly below it. A mass block of equal mass and a one-dimensional spiral acoustic black hole (SABH) are installed for comparison. Fig.10 is the mean square velocity level curve of the flat plate. It can be seen that the mass block of equal mass only reduces the peak value of the resonance peak at high frequency, which is because its inertial force in the high frequency band significantly suppresses the vibration of the web, and the one-dimensional spiral acoustic black hole also has a certain inhibitory effect on almost all peaks, but the effect is not good at low frequencies. After installing the two-dimensional acoustic black hole, the vibration of the flat plate is significantly suppressed, and almost all resonance peaks are significantly reduced. The vibration reduction effect is significantly better than that of the one-dimensional spiral acoustic black hole of equal mass. At the same time, it has little effect on the natural frequency of the structure.

[0068] The 2D SABH 2 is mounted at the same position on the plate, with the point excitation located directly below it. Fig.11 is the mean square velocity level curve of the flat plate. It can be seen that the two-dimensional acoustic black hole configuration II also has an excellent vibration reduction effect. Compared with the mass block of equal mass and the one-dimensional spiral acoustic black hole, it has a significant suppression effect on the resonance peak in the entire frequency band, and the effect is better in the low frequency band.

[0069] It can be seen that the two-dimensional acoustic black hole structure described in the present invention has the following advantages compared with the prior art:

[0070] 1. The traditional one-dimensional acoustic black hole is designed to be two-dimensional by rotating around an axis, which significantly enhances the directional independence of the acoustic black hole and can effectively control the propagation of waves in multiple directions, so there is no need to consider the layout direction, greatly reducing the impact of directionality on its performance and achieving a wider range of applications.

[0071] 2. The use of a two-dimensional spiral acoustic black hole structure can further enhance the vibration reduction effect of the acoustic black hole.

[0072] 3. Add damping to the tip damping of the two-dimensional acoustic black hole to effectively improve the vibration reduction performance of the acoustic black hole.

[0073] 4. The two-dimensional acoustic black hole is mainly designed by combining the advantages of one-dimensional acoustic black hole, dynamic vibration absorber, spiral structure and constrained damping.

[0074] 5. The present invention combines the advantages of the spiral acoustic black hole structure, such as lightweight, easy installation and low space occupancy, while broadening the one-dimensional acoustic black hole to a two-dimensional acoustic black hole, providing more degrees of freedom, allowing more flexible adjustment of the wave transmission path, and enhancing its ability to capture wave energy. It can further improve its low-frequency and broadband vibration reduction performance of the structure, and the effect of suppressing vibration is better.

[0075] According to the description and drawings of the present invention, those skilled in the art can easily manufacture or use a two-dimensional spiral acoustic black hole structure of the present invention, and can produce the positive effects recorded in the present invention.

[0076] Unless otherwise specified, in the present invention, the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicating orientation or positional relationships are based on the orientation or positional relationships shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the orientation or positional relationship in the present invention are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood in conjunction with the drawings and according to specific circumstances.

[0077] Unless otherwise clearly specified and limited, in the present invention, the terms "disposed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0078] The above is only a preferred embodiment of the present invention, but the present invention is not limited to the above specific embodiments. Those skilled in the art may make some modifications, supplements or use similar methods instead without departing from the principle of the present invention, which should also be regarded as the protection scope of the present invention.

Claims

1. A two-dimensional spiral acoustic black hole structure, characterized in that: The two-dimensional spiral acoustic black hole structure (1) comprises a two-dimensional acoustic black hole configuration I and / or a two-dimensional acoustic black hole configuration II, wherein the two-dimensional acoustic black hole configuration I is formed by rotating a one-dimensional spiral acoustic black hole (2) structure around a long side (221) of its base (22), and the two-dimensional acoustic black hole configuration II is formed by rotating a one-dimensional spiral acoustic black hole (2) structure around a short side (222) of its base (22); the one-dimensional spiral acoustic black hole (2) structure comprises a spiral curling portion (21) and a base (22), wherein the spiral curling portion (21) comprises an extended enhanced thickness portion (211), a damping portion (212) and a one-dimensional acoustic black hole slab (213) with a gradually varying thickness, wherein the damping portion (212 ) is tightly arranged on the inner wall of the extended enhanced thickness portion (211), and the inner end of the damping portion (212) is flush with the inner end of the extended enhanced thickness portion (211); the outer end of the extended enhanced thickness portion (211) is connected to the end of the base (22), and the one-dimensional acoustic black hole slat (213) is tightly arranged on the inner wall of the extended enhanced thickness portion (211) between the outer end of the damping portion (212) and the end of the base (22), the thicker end of the one-dimensional acoustic black hole slat (213) is connected to the end of the base (22), and the thinner end of the one-dimensional acoustic black hole slat (213) is connected to the damping portion (212).

2. The two-dimensional spiral acoustic black hole structure according to claim 1, characterized in that: The rotation angle of the one-dimensional spiral acoustic black hole (2) structure around the long side (221) or the short side (222) of its base (22) is 360°.

3. The two-dimensional spiral acoustic black hole structure according to claim 1, characterized in that: The lower surface (215) of the one-dimensional acoustic black hole slab (213) is a plane and is in close contact with the inner wall of the extended enhanced thickness portion (211), and the upper surface (214) of the one-dimensional acoustic black hole slab (213) is a wedge surface.

4. The two-dimensional spiral acoustic black hole structure according to claim 1, characterized in that: The thinner end of the one-dimensional acoustic black hole slab (213) is sandwiched between the extended enhanced thickness portion (211) and the damping portion (212).

5. The two-dimensional spiral acoustic black hole structure according to claim 1, characterized in that: When the one-dimensional acoustic black hole plate (213) strip is fully unfolded, the sum of the thickness of the one-dimensional acoustic black hole plate strip (213) and the corresponding extended enhanced thickness portion (211) below is h (x) The expression is: h (x) =H t +εx m ; Among them, H t is the thickness of the extended enhanced thickness portion; x is the abscissa; m is a constant, and m≥2; ε is the thickness coefficient used to scale the ABH.

6. The two-dimensional spiral acoustic black hole structure according to claim 1, characterized in that: The spirally curled portion (21) is formed by an extended enhanced thickness portion (211), a damping portion (212) and a one-dimensional acoustic black hole slab (213), and is spirally curled in the form of a standard Archimedean spiral.

7. The two-dimensional spiral acoustic black hole structure according to claim 1, characterized in that: The widths of the extended enhanced thickness portion (211), the damping portion (212) and the one-dimensional acoustic black hole slab (213) are all the same.

8. The two-dimensional spiral acoustic black hole structure according to claim 1, characterized in that: The thickness of the damping portion (212) should be twice as great as the thickness of the extended enhanced thickness portion (211).

9. The two-dimensional spiral acoustic black hole structure according to claim 1, characterized in that: The extended enhanced thickness portion (211) and the damping portion (212) are both strip-shaped structures with constant thickness.

10. The two-dimensional spiral acoustic black hole structure according to claim 1, characterized in that: The extended enhanced thickness portion (211) and the one-dimensional acoustic black hole slat (213) are both made of steel, and the damping portion (212) is made of asphalt.

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