Arrayed acoustic black hole ring oscillator and broadband vibration absorption device for pipes including it

Abstract

This invention discloses an array-type acoustic black hole ring vibrator and a broadband vibration absorption device for pipelines including the array-type acoustic black hole ring vibrator, belonging to the technical field of vibration reduction devices. The array-type acoustic black hole ring vibrator of this invention is fixed to the outside of an annular pipeline and includes several acoustic black hole structural units arranged in an array along the circumference of the annular pipeline. The distances between the outer and inner surfaces of each acoustic black hole structural unit and the radial central axis of the annular pipeline exhibit a smooth gradient change with a periodic variation, being larger at both ends and smaller at the center, forming an outer arc-shaped profile surface and an inner arc-shaped profile surface. A ring segment of constant thickness is also provided between every two acoustic black hole structural units. This invention can achieve lower frequency and wider frequency pipeline vibration suppression without changing the internal flow channel structure of the pipeline or causing any damage to the pipeline.

Description

Technical Field

[0001] This invention belongs to the field of vibration reduction device technology, specifically relating to an array-type acoustic black hole ring vibrator and a broadband vibration absorption device for pipelines including the array-type acoustic black hole ring vibrator. Background Technology

[0002] Pipelines are widely used in many critical industries such as nuclear power, thermal power, aerospace, petrochemicals, and shipbuilding. Their vibrations originate from multiple factors. On the one hand, fluctuations in fluid velocity and pressure pulsations within the pipe can induce vibrations. For example, in reciprocating compressor pipelines in the petrochemical industry, pressure pulsations are the primary source of vibration. On the other hand, mechanical vibrations generated by pumps, engines, and other equipment connected to the pipeline are transmitted to the pipeline through connectors. The frequencies of these vibrations are not fixed and cover a wide range from low to high frequencies. Moreover, the frequencies change with operating conditions, such as equipment start-up and shutdown, and load adjustments, all of which cause vibration frequency shifts. Traditional pipeline vibration reduction methods often employ methods such as laying damping materials and single-frequency dynamic vibration absorbers. The laying of damping materials is limited by space and installation conditions, making it difficult to apply in scenarios with stringent safety and structural space requirements, such as nuclear power, thermal power, and aerospace. Traditional dynamic vibration absorbers can only function for specific frequency vibrations. When the pipeline vibration frequency changes due to altered operating conditions, the vibration reduction effect decreases significantly, failing to meet the complex and ever-changing actual engineering needs.

[0003] Acoustic black holes (ABH) are a novel passive vibration reduction technology. Their structural cross-sectional thickness gradually decreases according to a power function, creating a gradient change in structural impedance. This allows for control of the propagation characteristics of bending waves within the structure, achieving broadband vibration reduction. Existing embedded acoustic black hole vibration reduction structures, while capable of controlling bending waves and vibrations, require tailoring to the existing structure, causing irreversible damage to the stiffness and strength of the product, directly impacting the safety and lifespan of the equipment. There are also non-embedded vibration reduction structures based on acoustic black holes, typically attached inside pipes and rigidly connected to the pipes using bolts or welding. This method can also cause stress concentration in the structure and affect the internal flow channel structure of the pipe.

[0004] Therefore, given the problems of existing pipeline vibration reduction measures, such as single vibration absorption and reduction frequency, narrow operating bandwidth, damage to structural strength and stiffness, and impact on the internal flow channel of the pipeline, the development of a new broadband vibration absorption device adapted to pipeline vibration reduction has significant engineering needs and application potential. Summary of the Invention

[0005] The purpose of this invention is to provide an array-type acoustic black hole ring oscillator and a broadband vibration absorption device for pipelines including the array-type black hole ring oscillator, which can achieve lower frequency and wider frequency pipeline vibration suppression without changing the internal flow channel structure of the pipeline or causing any damage to the pipeline.

[0006] Specifically, on the one hand, the present invention provides an array-type acoustic black hole ring vibrator, fixed on the outside of an annular pipe for vibration reduction of the annular pipe, comprising a plurality of acoustic black hole structural units distributed in an array along the circumference of the annular pipe, wherein the distance between the outer and inner surfaces of each acoustic black hole structural unit and the radial central axis of the annular pipe varies periodically with a smooth gradient that is larger at both ends and smaller at the center, forming an outer arc-shaped contour surface and an inner arc-shaped contour surface; and a ring segment of constant thickness is also provided between every two acoustic black hole structural units.

[0007] Furthermore, the distance between the outer arc-shaped contour surface and the radial central axis of the annular pipe exhibits a first smooth gradient change, and the distance between the inner arc-shaped contour surface and the radial central axis of the annular pipe exhibits a second smooth gradient change.

[0008] Furthermore, the smooth gradient change conforms to the following power function variation law: ;

[0009] in, The distance between the outer arc-shaped contour surface or the inner arc-shaped contour surface and the radial central axis surface of the annular pipe. It is half the thickness of the center of the acoustic black hole structural unit. The angle through which a point on the outer or inner curved surface rotates relative to one end of the acoustic black hole structural unit. Let be the angle through which the center of the acoustic black hole structural unit rotates relative to one end of the acoustic black hole structural unit, and let be the angle between the two ends of the acoustic black hole structural unit. , m is the power of the power function's variation law, and , The slope of the cross section of the acoustic black hole structural unit. .

[0010] Furthermore, a damping layer is provided at the center of each of the acoustic black hole structural units.

[0011] Furthermore, the ring segment with constant thickness is provided with holes to fix the arrayed acoustic black hole ring oscillator on the outside of the ring pipe.

[0012] Furthermore, the array-type acoustic black hole ring oscillator is composed of several arc segments forming a ring, with coaxial surfaces distributed around the outer periphery of the ring pipe.

[0013] On the other hand, the present invention also provides a broadband vibration absorption device for pipelines, including an annular pipeline clamping structure and a plurality of arrayed acoustic black hole annular vibrators arranged in parallel along the axial direction of the annular pipeline; the annular pipeline clamping structure is fixed to the outer periphery of the annular pipeline, and the arrayed acoustic black hole annular vibrators are rigidly connected to the outer side of the annular pipeline clamping structure.

[0014] Furthermore, in each of the parallel arrayed acoustic black hole ring oscillators, the smooth gradient changes conform to different power function variation laws.

[0015] Furthermore, the smooth gradient change conforms to the following power function variation law: ;

[0016] in, The distance between the outer arc-shaped contour surface or the inner arc-shaped contour surface and the radial central axis surface of the annular pipe clamping structure. It is half the thickness of the center of the acoustic black hole structural unit, and is the angle through which a point on the outer or inner arc-shaped contour surface rotates relative to one end of the acoustic black hole structural unit. Let be the angle through which the center of the acoustic black hole structural unit rotates relative to the two ends of the acoustic black hole structural unit, and let be the angle between the two ends of the acoustic black hole structural unit. , Let be the power of the power function law obeyed by the distance between the outer or inner arc-shaped contour surface of the acoustic black hole structural unit on the i-th-order arrayed acoustic black hole ring oscillator and the radial central axis surface of the ring pipe clamping structure, and , Let be the slope of the cross-section of the acoustic black hole structural unit on the i-th order arrayed acoustic black hole ring oscillator. .

[0017] Furthermore, the power of the power function law that governs the distance between the outer arc-shaped contour surface or the inner arc-shaped contour surface and the radial central axis surface of the annular pipe clamping structure is set according to the frequency or frequency band range corresponding to the larger amplitude in the actual vibration reduction requirements.

[0018] The beneficial effects of the array-type acoustic black hole ring oscillator and the broadband vibration absorption device for pipes including the present invention are as follows:

[0019] The present invention discloses an array-type acoustic black hole ring vibrator and a broadband vibration absorption device for pipelines including the array-type acoustic black hole ring vibrator. The ring vibrator is composed of a ring clamping structure and a multi-level ring vibrator embedded with array-type acoustic black hole structural units to form a multi-level vibration absorption device. The clamping structure can adapt well to the pipeline and make a tight connection without changing the pipeline stiffness, strength and flow channel structure, so as to effectively transmit the vibration to the multi-level ring vibrator embedded with array-type acoustic black holes.

[0020] Compared to traditional vibration absorbers, acoustic black hole structural units can better concentrate mid- and high-frequency vibration energy in the acoustic black hole region. The array structure and multi-level configuration also better generate Bragg scattering, concentrating lower-frequency and different-band vibration energy in the acoustic black hole region, thereby improving the system's efficiency in capturing low-frequency and different-band vibration energy. Simultaneously, the damping layer adhered to the acoustic black hole region enhances the dissipation efficiency of the vibration energy concentrated there, thus improving the low-frequency and broadband vibration suppression effect of pipeline structures in various environments such as aerospace, thermal power, and nuclear power.

[0021] By combining multi-level acoustic black hole structures with different parameters and using a ring oscillator for vibration absorption, the vibration absorption device of this invention has a wider effective operating frequency band and a lower initial operating frequency, thereby achieving a more ideal pipeline vibration suppression effect.

[0022] The array-type acoustic black hole ring oscillator and the pipeline broadband vibration absorption device including the present invention have a compact and simple structure, are suitable for pipelines, and are easy to use. They have characteristics such as low cutoff frequency, wide effective frequency range, and robust damping characteristics, which can improve the vibration energy dissipation efficiency and realize broadband vibration suppression of pipelines, and have broad application prospects. Attached Figure Description

[0023] Figure 1 This is an enlarged schematic diagram of the array-type acoustic black hole ring oscillator and acoustic black hole structural unit according to an embodiment of the present invention.

[0024] Figure 2 This is a schematic diagram illustrating the gradient variation of the inner and outer arc-shaped surfaces of the acoustic black hole structural unit according to an embodiment of the present invention.

[0025] Figure 3 This is a schematic diagram of the annular pipe clamping structure according to an embodiment of the present invention.

[0026] Figure 4 This is a schematic diagram of the connection method of the annular pipe clamping structure according to an embodiment of the present invention.

[0027] Figure 5 This is a schematic diagram of an embodiment of the annular pipe clamping structure of the present invention.

[0028] Figure 6 This is a schematic diagram of the structure of a broadband vibration absorption device for pipelines (single-stage array acoustic black hole ring oscillator) according to an embodiment of the present invention.

[0029] Figure 7 This is a schematic diagram of the structure of the pipeline broadband vibration absorption device (multi-stage array acoustic black hole ring oscillator) according to an embodiment of the present invention.

[0030] Figure 8 This is a schematic diagram of the structure of a broadband vibration absorption device (including a damping layer) for pipelines according to an embodiment of the present invention.

[0031] Figure 9 for Figure 8 A schematic diagram of the implementation status of a broadband vibration absorption device for pipelines.

[0032] Figure 10 The figure shows the simulation results of pipeline vibration reduction according to an embodiment of the present invention.

[0033] The diagram is labeled as follows: 1-ring pipe, 2-ring pipe clamping structure, 21-two half-rings of the ring pipe clamping structure, 211-folded edge, 22-threaded hole on the surface of the ring pipe clamping structure, 3-arrayed acoustic black hole ring vibrator, 31-half-ring of the arrayed acoustic black hole ring vibrator, 32-acoustic black hole structural unit, 321-outer arc-shaped surface, 322-inner arc-shaped surface, 33-ring segment with constant thickness, 331-hole, 4-damping layer, 5-fastening block, 6-connecting bolt, 7-double-layered gasket. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the embodiments and the accompanying drawings.

[0035] One embodiment of the present invention is an array-type acoustic black hole ring oscillator. For example... Figure 1 As shown, the array-type acoustic black hole ring vibrator 3 of the present invention can be fixed on the outside of the annular pipe for vibration reduction of the annular pipe. The array-type acoustic black hole ring vibrator 3 includes a plurality of acoustic black hole structural units 32 distributed in an array along the circumference of the annular pipe 1. The distance between the outer and inner surfaces of each acoustic black hole structural unit and the radial central axis of the annular pipe 1 varies periodically with a smooth gradient that is larger at both ends and smaller at the center, forming an outer arc-shaped contour surface 321 and an inner arc-shaped contour surface 322; a ring segment 33 of constant thickness is also provided between every two acoustic black hole structural units 32.

[0036] like Figure 2 As shown, the distances between the outer arc-shaped contour surface 321 and the inner arc-shaped contour surface 322 of each acoustic black hole structural unit 32 and the radial central axis of the annular pipe 1 conform to a smooth gradient change, which follows a power function variation law:

[0037] in, The distance between the outer arc-shaped contour surface or the inner arc-shaped contour surface and the radial central axis surface of the annular pipe. It is half the thickness of the center of the acoustic black hole structural unit. The angle through which a point on the outer or inner curved surface rotates relative to one end of the acoustic black hole structural unit. Let be the angle through which the center of the acoustic black hole structural unit rotates relative to one end of the acoustic black hole structural unit, and let be the angle between the two ends of the acoustic black hole structural unit. , m is the power of the power function's variation law, and , The slope of the cross section of the acoustic black hole structural unit. .

[0038] Preferably, in another embodiment, the inner and outer powers are inconsistent. The distance between the outer arc-shaped contour surface 321 and the radial central axis of the annular pipe 1 varies with a first smooth gradient, and the distance between the inner arc-shaped contour surface 322 and the radial central axis of the annular pipe 1 varies with a second smooth gradient. By combining the two gradient changes, the vibration reduction effects of the first and second gradient contour changes can be superimposed simultaneously, thereby suppressing vibrations in different frequencies or different frequency bands.

[0039] Preferably, the arrayed acoustic black hole ring oscillator is composed of several arc segments forming a ring, for example... Figure 1 The two arrayed acoustic black hole ring oscillator half-rings 31 shown form a ring, with their coaxial surfaces distributed around the outer periphery of the ring pipe 1.

[0040] like Figure 3 , Figure 4 and Figure 5 As shown, the annular pipe clamping structure 2 includes two semi-rings 21 with folded edges, connected by a fastening block 5, bolts 6, and double-layered washers 7. The fastening block 5 is placed inside the folded edge 211 (the folded edge) of the annular pipe clamping structure 2 and is fastened to the folded edge 211 by bolts 6 and double-layered washers 7. The two semi-rings 21 of the annular pipe clamping structure 2 are also connected by bolts 6 and double-layered washers 7. Meanwhile, threaded holes 22 are evenly distributed on the annular pipe clamping structure 2. Figure 5 As shown, the annular pipe clamping structure 2 is installed on the annular pipe 1 to be damped. The annular pipe clamping structure 2 can be locked and fixed on the annular pipe 1 by tightening the bolts 6 that connect the two half rings 21 of the annular pipe clamping structure 2.

[0041] like Figures 6-9 As shown, the broadband vibration absorption device for pipelines of the present invention includes an annular pipeline clamping structure 2 and at least one array of acoustic black hole annular vibrators 3 arranged in parallel along the axial direction of the annular pipeline 1; the annular pipeline clamping structure 2 is fixed to the outer periphery of the annular pipeline 1, and the array of acoustic black hole annular vibrators 3 is rigidly connected to the outer side of the annular pipeline clamping structure 2. Each array of acoustic black hole annular vibrators 3 is a primary vibration absorption structure.

[0042] Preferably, in another embodiment, the constant-thickness ring segment 33 is provided with a hole 331, such as a through hole or a threaded hole, to fix the arrayed acoustic black hole ring vibrator 3 to the annular pipe clamping structure 2, i.e., the outside of the annular pipe 1. For example, a bolt is used to fix the arrayed acoustic black hole ring vibrator 3 to the annular pipe clamping structure 2, i.e., the outside of the annular pipe 1, by passing a bolt through the hole 331 on the constant-thickness ring segment 33 between two acoustic black hole structural units and engaging it with the threaded hole 22 on the annular pipe clamping structure 2.

[0043] Preferably, in another embodiment, a damping layer 4 is provided at the center of each acoustic black hole structural unit 32. Adhering damping material to the center of the acoustic black hole structural unit 32 to form the damping layer 4 can further improve the energy dissipation efficiency of the structure and achieve a stable broadband vibration reduction effect.

[0044] like Figure 8 , Figure 9 The illustrated broadband vibration-absorbing device for a pipe includes an annular pipe clamping structure 2 and six arrayed acoustic black hole annular vibrators 3 arranged side-by-side along the axial direction of the annular pipe 1. The annular pipe clamping structure 2 is fixed to the outer periphery of the annular pipe 1 to be damped, maintaining its inner surface in contact with the outer surface of the annular pipe 1. The arrayed acoustic black hole annular vibrators 3 are rigidly connected to the outer side of the annular pipe clamping structure 2. The six arrayed acoustic black hole annular vibrators 3 are arranged side-by-side along the axial direction of the annular pipe 1 on the annular pipe clamping structure 2 to form a six-stage vibration-absorbing structure. The damping layer 4 is distributed at the midpoint between the outer arcuate surface 321 and the inner arcuate surface 322 of each acoustic black hole structural unit.

[0045] Preferably, in another embodiment, the smooth gradient changes in the distance between the outer arcuate contour surface 321 or the inner arcuate contour surface 322 of each of the parallel-distributed array-type acoustic black hole ring oscillators and the radial central axis of the annular pipe clamping structure 2 conform to different power function variation laws. By combining acoustic black hole ring oscillators whose structural contour thickness follows different power law variations, the vibration reduction effects brought by each ring oscillator can be superimposed simultaneously, achieving vibration suppression at more characteristic frequencies and over a wider frequency band.

[0046] Preferably, in another embodiment, the smooth gradient change conforms to the following power function variation law:

[0047] in, The distance between the outer arc-shaped contour surface or the inner arc-shaped contour surface and the radial central axis surface of the annular pipe clamping structure. It is half the thickness of the center of the acoustic black hole structural unit, and is the angle through which a point on the outer or inner arc-shaped contour surface rotates relative to one end of the acoustic black hole structural unit. Let be the angle through which the center of the acoustic black hole structural unit rotates relative to the two ends of the acoustic black hole structural unit, and let be the angle between the two ends of the acoustic black hole structural unit. , Let be the power of the power function law obeyed by the distance between the outer or inner arc-shaped contour surface of the acoustic black hole structural unit on the i-th-order arrayed acoustic black hole ring oscillator and the radial central axis surface of the ring pipe clamping structure, and , Let be the slope of the cross-section of the acoustic black hole structural unit on the i-th order arrayed acoustic black hole ring oscillator. .

[0048] Preferably, in another embodiment, the power of the power function law governing the distance between the outer or inner arc-shaped contour surface and the radial central axis of the annular pipe clamping structure is set according to the frequency or frequency band corresponding to the larger amplitude in the actual vibration reduction requirement. By setting the power of the power function law governing the distance between the outer or inner arc-shaped contour surface and the radial central axis of the annular pipe clamping structure, the smoothing gradient of the outer or inner arc-shaped contour surface is adjusted, thereby reducing the vibration amplitude in the corresponding frequency or frequency band in the actual vibration reduction requirement. For example, if the vibration amplitude of the pipe surface requiring vibration reduction is large in one or more frequency or frequency bands, through simulation, the power of the power function law governing the distance between the outer or inner arc-shaped contour surface and the radial central axis of the annular pipe clamping structure is adjusted to adjust the smoothing gradient of the outer or inner arc-shaped contour surface, thereby reducing the vibration amplitude in the corresponding frequency or frequency band. For example, if the vibration amplitude of the pipe surface to be vibration-damped is large in the 200Hz or 400-450Hz range, then the power function m of the distance between the outer or inner arc-shaped contour surface and the radial central axis of the annular pipe clamping structure is set to 3. If the vibration amplitude of the pipe to be vibration-damped is large in multiple frequency or frequency band ranges, then the power function m of the distance between the outer or inner arc-shaped contour surface and the radial central axis of the annular pipe clamping structure on the acoustic black hole structural unit of different levels of the arrayed acoustic black hole ring vibrator is set to different values. In another embodiment, the arrayed acoustic black hole ring vibrator contains six levels, and the power function m of the distance between the outer or inner arc-shaped contour surface of the acoustic black hole structural unit of each level is set to 3. Similarly, the powers of the sixth-order acoustic black hole ring oscillator along the axial direction are as follows: , , , 5, , 7. The vibration response of the pipe with the embedded array-type acoustic black hole ring oscillator was compared with that of the pipe without the embedded vibration-absorbing structure through finite element simulation analysis. Figure 10 As shown in the figure, after the external array-type acoustic black hole ring oscillator is set, the root mean square velocity response of the pipe surface exhibits an ideal vibration suppression effect at peak frequencies of 70Hz, 85Hz, 115Hz, and 180Hz, as well as in the range of 250Hz to 1000Hz. The average suppression of the root mean square velocity response of the pipe surface reaches more than 15dB.

[0049] The present invention discloses an array-type acoustic black hole ring vibrator and a broadband vibration absorption device for pipelines including the array-type acoustic black hole ring vibrator. The ring vibrator is composed of a ring clamping structure and a multi-level ring vibrator embedded with array-type acoustic black hole structural units to form a multi-level vibration absorption device. The clamping structure can adapt well to the pipeline and make a tight connection without changing the pipeline stiffness, strength and flow channel structure, so as to effectively transmit the vibration to the multi-level ring vibrator embedded with array-type acoustic black holes.

[0050] Compared to traditional vibration absorbers, acoustic black hole structural units can better concentrate mid- and high-frequency vibration energy in the acoustic black hole region. The array structure and multi-level configuration also better generate Bragg scattering, concentrating lower-frequency and different-band vibration energy in the acoustic black hole region, thereby improving the system's efficiency in capturing low-frequency and different-band vibration energy. Simultaneously, the damping layer adhered to the acoustic black hole region enhances the dissipation efficiency of the vibration energy concentrated there, thus improving the low-frequency and broadband vibration suppression effect of pipeline structures in various environments such as aerospace, thermal power, and nuclear power.

[0051] By combining multi-level acoustic black hole structures with different parameters and using a ring oscillator for vibration absorption, the vibration absorption device of this invention has a wider effective operating frequency band and a lower initial operating frequency, thereby achieving a more ideal pipeline vibration suppression effect.

[0052] The array-type acoustic black hole ring oscillator and the pipeline broadband vibration absorption device including the present invention have a compact and simple structure, are suitable for pipelines, and are easy to use. They have characteristics such as low cutoff frequency, wide effective frequency range, and robust damping characteristics, which can improve the vibration energy dissipation efficiency and realize broadband vibration suppression of pipelines, and have broad application prospects.

[0053] While the present invention has been disclosed above with reference to preferred embodiments, these embodiments are not intended to limit the invention. Any equivalent changes or modifications made without departing from the spirit and scope of the invention are also within the scope of protection of the invention. Therefore, the scope of protection of the present invention should be determined by the claims of this application.

Claims

1. An array-type acoustic black hole ring vibrator, fixed to the outside of a ring-shaped pipe for vibration damping of the ring-shaped pipe, characterized in that, It includes several acoustic black hole structural units distributed in a circumferential array along the annular pipe. The distance between the outer and inner surfaces of each acoustic black hole structural unit and the radial central axis of the annular pipe varies periodically with a smooth gradient that is larger at both ends and smaller at the center, forming an outer arc-shaped contour surface and an inner arc-shaped contour surface. A ring segment with constant thickness is also provided between every two acoustic black hole structural units.

2. The array-type acoustic black hole ring oscillator according to claim 1, characterized in that, The distance between the outer arc-shaped contour surface and the radial central axis of the annular pipe varies with a first smooth gradient, and the distance between the inner arc-shaped contour surface and the radial central axis of the annular pipe varies with a second smooth gradient.

3. The array-type acoustic black hole ring oscillator according to claim 1, characterized in that, The smooth gradient change follows the following power function variation law: ； in, The distance between the outer arc-shaped contour surface or the inner arc-shaped contour surface and the radial central axis surface of the annular pipe. It is half the thickness of the center of the acoustic black hole structural unit. The angle through which a point on the outer or inner curved surface rotates relative to one end of the acoustic black hole structural unit. Let be the angle through which the center of the acoustic black hole structural unit rotates relative to one end of the acoustic black hole structural unit, and let be the angle between the two ends of the acoustic black hole structural unit. , m is the power of the power function's variation law, and , The slope of the cross section of the acoustic black hole structural unit. .

4. The array-type acoustic black hole ring oscillator according to claim 1, characterized in that, Each of the acoustic black hole structural units has a damping layer at its center.

5. The array-type acoustic black hole ring oscillator according to any one of claims 1, characterized in that, The ring segment with constant thickness is provided with holes to fix the arrayed acoustic black hole ring oscillator on the outside of the ring pipe.

6. The array-type acoustic black hole ring oscillator according to claim 1, characterized in that, The array-type acoustic black hole ring oscillator is composed of several arc segments forming a ring, with coaxial surfaces distributed around the outer periphery of the ring pipe.

7. A broadband vibration absorption device for pipelines, characterized in that, It includes an annular pipe clamping structure and several arrayed acoustic black hole annular vibrators arranged in parallel along the axial direction of the annular pipe; the annular pipe clamping structure is fixed to the outer periphery of the annular pipe, and the arrayed acoustic black hole annular vibrators are rigidly connected to the outer side of the annular pipe clamping structure.

8. The broadband vibration absorption device for pipelines according to claim 7, characterized in that, In each of the parallel arrayed acoustic black hole ring oscillators, the smooth gradient changes conform to different power function variation laws.

9. The broadband vibration absorption device for pipelines according to claim 8, characterized in that, The smooth gradient change follows the following power function variation law: ； in, The distance between the outer arc-shaped contour surface or the inner arc-shaped contour surface and the radial central axis surface of the annular pipe clamping structure. It is half the thickness of the center of the acoustic black hole structural unit, and is the angle through which a point on the outer or inner arc-shaped contour surface rotates relative to one end of the acoustic black hole structural unit. Let be the angle through which the center of the acoustic black hole structural unit rotates relative to the two ends of the acoustic black hole structural unit, and let be the angle between the two ends of the acoustic black hole structural unit. , Let be the power of the power function law obeyed by the distance between the outer or inner arc-shaped contour surface of the acoustic black hole structural unit on the i-th order arrayed acoustic black hole ring oscillator and the radial central axis surface of the ring pipe clamping structure, and , Let be the slope of the cross-section of the acoustic black hole structural unit on the i-th order arrayed acoustic black hole ring oscillator. .

10. The broadband vibration absorption device for pipelines according to claim 9, characterized in that, The power of the distance between the outer arc-shaped contour surface or the inner arc-shaped contour surface and the radial central axis surface of the annular pipe clamping structure is determined by a power function, with the power number set according to the frequency or frequency band corresponding to the larger amplitude in the actual vibration reduction requirements.

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