Pressure-torsion unit and acoustic black hole coupled shock absorber

Abstract

The invention relates to the field of vibration damping devices, and particularly discloses a compression-torsion unit and acoustic black hole coupled vibration damper which comprises at least three acoustic black hole plates and a plurality of compression-torsion units, the acoustic black hole plates are arranged at intervals in the axial direction of the acoustic black hole plates, and a gap is formed between every two adjacent acoustic black hole plates; the plurality of pressing and twisting units are arranged in the gap at equal intervals in the circumferential direction of the acoustic black hole plate; the number of the pressing and twisting units in each layer of gap is the same, and the arrangement direction of the pressing and twisting units in the multiple layers of gaps is parallel to the axial direction of the acoustic black hole plate; in the same layer of gap, the compression and torsion directions of the plurality of compression and torsion units are consistent; and in two adjacent layers of gaps, the compression and torsion directions of the compression and torsion units are opposite. Through the synergistic effect of the elastic wave focusing effect of the acoustic black hole and the compression-torsion coupling energy consumption mechanism of the compression-torsion unit, an obvious vibration reduction band gap can be opened in a low-frequency band, the band gap boundary is smooth, the coverage range is wide, and the low-frequency vibration suppression effect is remarkable.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vibration reduction devices, in particular to a vibration damper with a compression-torsion unit coupled with an acoustic black hole. BACKGROUND

[0002] At present, rubber dampers or air bag dampers are often used to achieve vibration reduction between the installation base of the running equipment, the pipe clamp and the foundation. Most of these vibration reduction devices rely on rubber components, which have poor radiation resistance and high temperature resistance, and have very limited applicability in nuclear reactors and other environments with strong radiation, high temperature and corrosive environment. In addition, the existing acoustic black hole vibration reduction structure mostly adopts an embedded or additional design: the embedded type needs to be slotted on the component to be damped, which can easily weaken the structural mechanical properties, and a larger slot body is often needed to achieve low-frequency vibration reduction, which further affects the carrying capacity; the additional acoustic black hole sheet body faces the problems of limited installation space and low coupling efficiency with the main structure, resulting in poor vibration energy transmission and dissipation effect. Therefore, how to achieve high carrying capacity, environmental interference resistance and low-frequency wide-band vibration reduction in a limited space is still a bottleneck for the acoustic black hole technology to move from theory to engineering application. SUMMARY

[0003] In order to achieve high carrying capacity, environmental interference resistance and low-frequency wide-band vibration reduction in a limited space, the present application provides a vibration damper with a compression-torsion unit coupled with an acoustic black hole.

[0004] The vibration damper with a compression-torsion unit coupled with an acoustic black hole provided by the present application adopts the following technical solution: A vibration damper with a compression-torsion unit coupled with an acoustic black hole, comprising: An acoustic black hole plate, at least three are provided, a plurality of acoustic black hole plates are arranged at intervals along the axial direction thereof, and a gap is provided between two adjacent acoustic black hole plates; A plurality of compression-torsion units are arranged at equal intervals in the gaps along the circumferential direction of the acoustic black hole plate; the number of compression-torsion units in each layer of gaps is the same, the arrangement direction of the compression-torsion units in the multiple layers of gaps is parallel to the axial direction of the acoustic black hole plate; in the same layer of gaps, the compression and torsion directions of the plurality of compression-torsion units are consistent; in the adjacent two layers of gaps, the compression and torsion directions of the compression-torsion units are opposite.

[0005] The application constructs a high-efficiency composite damping structure in three-dimensional space by periodically stacking and coupling multiple acoustic black hole plates and directionally alternating torsion units, and the periodic positive and negative alternating arrangement can greatly optimize the transmission path of vibration energy. Through the successive reverse torsion of multiple layers of torsion units, linear axial vibration is fully converted into torsional deformation and dissipated, significantly improving the suppression efficiency of low-frequency vibration. At the same time, the structure forms a periodic vibration isolation system with adjustable band gap in the vertical direction. The coupling motion of the acoustic black hole region local vibration and the torsion unit opens or closes the band gap, which can be adjusted to produce a wide and flat forbidden band for low-frequency bands, and achieve excellent broadband vibration isolation effect on the core channel of vibration transmission.

[0006] Further, the spacing between the two adjacent acoustic black hole plates is equal.

[0007] The equidistant arrangement of the acoustic black hole plates ensures the symmetry and uniformity of the entire damper in force and vibration transmission, avoids stress concentration or local modal imbalance problems caused by unequal spacing, and makes the cooperative energy dissipation of the multi-layer torsion unit more stable and efficient, which is conducive to producing more regular and ideal vibration band gap characteristics.

[0008] Further, the torsion unit comprises a circular ring and two plate-shaped elastic members fixed to the outer periphery of the circular ring, the plate-shaped elastic members are arranged along the tangential direction of the outer periphery of the circular ring, and the two plate-shaped elastic members are centrally symmetric relative to the axis of the circular ring, and the ends of the two plate-shaped elastic members are respectively fixed to the two acoustic black hole plates.

[0009] The symmetrical elastic structure design of the torsion unit can guide the torsional motion of the circular ring by the elastic deformation of the plate-shaped elastic members when bearing axial pressure, efficiently converting the pressure into torsional shear force, thereby maximizing the energy dissipation mechanism of compression-torsion coupling and improving the energy conversion efficiency and reliability of the damper.

[0010] Further, the installation angles of the multiple torsion units in the same layer of the gap are consistent; the installation angles of the torsion units in the adjacent two layers of the gap are symmetric about the plane where the acoustic black hole plates are located.

[0011] This symmetrical layout makes the responses of the torsion units in adjacent gap layers to vibration input cooperate with each other in phase, which can further optimize the propagation characteristics of waves in the structure, effectively widen the width of the vibration isolation band gap, and enhance the dissipation capacity of vibration energy in multiple directions.

[0012] Further, the acoustic black hole plate comprises an outer ring, an acoustic black hole region and a damping region arranged in sequence from outside to inside.

[0013] Further, the outer ring of the acoustic black hole plate located at both ends is provided with a bolt hole.

[0014] Furthermore, one end of the acoustic black hole plate is connected to the device to be vibration damped, and the other end of the acoustic black hole plate is connected to the foundation or base.

[0015] Through the integrated design of "load-bearing" and "vibration reduction" functions, the outer ring of the acoustic black hole plate provides solid mechanical support and installation interface to ensure structural strength and load-bearing capacity; the internal acoustic black hole region focuses on dissipating energy through the elastic wave focusing effect, and the damping region further enhances the dissipation efficiency.

[0016] The bolt holes on the outer ring provide a standardized and reliable mechanical interface, which allows the vibration damper to be easily connected in series to the main "force flow" channel between the equipment and the foundation (such as under the equipment foot or pipe clamp), making installation convenient and easy to integrate into existing engineering structures, and highly practical.

[0017] Furthermore, it also includes multiple additional acoustic black holes, which are equally spaced along the circumference of the acoustic black hole plate in the gap.

[0018] Based on the existing interlayer compression and torsion energy dissipation, by introducing additional local resonant units, it is possible to excite richer vibration modes, which can couple and synergize with the band gap of the main structure, thereby further widening the vibration isolation frequency band or achieving a deeper vibration reduction effect in a specific frequency band.

[0019] Furthermore, the additional acoustic black hole is a wedge-shaped or bilobed acoustic black hole.

[0020] Acoustic black holes with different configurations have different wave velocity modulation and energy focusing characteristics, which provides design flexibility. The optimal configuration can be selected according to the needs of the target vibration reduction frequency band, so as to achieve precise and customizable vibration reduction performance optimization.

[0021] Furthermore, the additional acoustic black hole is vertically connected between the two acoustic black hole plates, or the additional acoustic black hole is obliquely connected between the two acoustic black hole plates.

[0022] The installation angle of the additional acoustic black hole provides an extra design dimension for bandgap control, which helps to achieve better adaptive adjustments for vibrations in specific directions or complex vibration environments.

[0023] In summary, this application includes at least one of the following beneficial technical effects: 1. This application utilizes the synergistic effect of the elastic wave focusing effect of the acoustic black hole and the compression-torsion coupling energy dissipation mechanism of the compression-torsion unit to open a significant vibration reduction band gap in the low-frequency band. The band gap has a gentle boundary and a wide coverage range, resulting in a significant suppression effect on low-frequency vibrations. At the same time, the black hole cover plate adopts a functional zoning design with an outer ring bearing and an inner ring thinning, which not only ensures the structural bearing capacity and safety but also fully utilizes the local resonance effect of the acoustic black hole, overcoming the inherent problems of embedded black holes weakening the main structure or the low coupling efficiency of additional black holes. 2. This application has good modal adjustability and layout flexibility. By changing the periodic arrangement of the acoustic black hole plate and the compression and torsion unit, the bandgap frequency range and vibration reduction characteristics can be effectively controlled to adapt to the vibration reduction requirements of different frequency bands. This application can be directly installed as an independent vibration reduction element on the main vibration transmission path such as equipment base or pipe clamps, which not only facilitates engineering implementation, but also provides a brand-new solution for vibration control under high load and harsh environmental conditions. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application; Figure 2 This is a schematic diagram of the structure of the acoustic black hole plate in an embodiment of this application; Figure 3 This is a schematic diagram of a comparative model of the quality equivalence of embodiments of this application; Figure 4 These are bandgap energy band diagrams of the embodiments of this application and the comparative model during the vertical period, wherein (a) is the energy band diagram of the comparative model that is mass equivalent to the embodiments of this application, and (b) is the energy band diagram of the vertical period vibration damper of the embodiments of this application; Figure 5 These are the bandgap lower and upper boundary mode shapes in this application embodiment, where (a) is mode shape A (k=1.25, characteristic frequency=42.124Hz), (b) is mode shape B (k=1.25, characteristic frequency=97.126Hz), (c) is mode shape C (k=1.25, characteristic frequency=245.2Hz), and (d) is mode shape D (k=1.25, characteristic frequency=297.06Hz).

[0025] Reference numerals: 1. Upper cover acoustic black hole; 11. Outer ring of cover; 12. Acoustic black hole region of cover; 13. Damping region of cover; 14. Bolt hole; 2. Compression and torsion unit; 21. Ring; 22. Plate-shaped elastic element; 3. Middle cover acoustic black hole; 4. Additional acoustic black hole; 41. Outer ring of additional acoustic black hole; 42. Additional acoustic black hole region; 43. Damping region of additional acoustic black hole; 5. Lower cover acoustic black hole. Detailed Implementation

[0026] The following is in conjunction with the appendixFigures 1-5 This application will be described in further detail.

[0027] This application discloses a vibration damper that couples a compression-torsion unit to an acoustic black hole. (Refer to...) Figure 1 The vibration damper coupled to the compression-torsion unit and the acoustic black hole includes multiple acoustic black hole plates and multiple compression-torsion units 2. In this embodiment, three acoustic black hole plates are set, namely, an upper cover acoustic black hole 1, a middle cover acoustic black hole 3, and a lower cover acoustic black hole 5. The three acoustic black hole plates are arranged at equal intervals along their own axial direction, and the gap distance between two adjacent acoustic black hole plates is 100mm. In other feasible embodiments, the number of acoustic black hole plates can be set to more, as long as the periodic arrangement requirement is met; as the number of acoustic black hole plates increases, the bandgap energy vibration reduction effect will increase.

[0028] Reference Figure 1 and Figure 2 The acoustic black hole plate is circular and includes, from the outside to the inside, an outer ring 11, an acoustic black hole region 12, and a damping region 13. The outer ring 11 has a thickness h1 = 6 mm, an outer diameter a2 = 170 mm, and an inner diameter a1 = 140 mm. The thickness of the acoustic black hole region 12 decreases from the outside to the inside according to a power function, with the thickness variation rule being: h = ea m +h0, where a is the distance from a point within the acoustic black hole region to the thinnest point in that region, h is the thickness of the longitudinal section at that point, e is a coefficient, the black hole section coefficient m=3, and the black hole truncation thickness h0=1mm. The damping thickness h of the cover plate damping region 13. d =2mm, damping diameter b d =10mm.

[0029] Acoustic black hole plates can focus and dissipate energy, improving vibration reduction; at the same time, the rich local resonance modes within the acoustic black hole can adjust the upper and lower boundary modes of the band gap, thus regulating the band gap.

[0030] Reference Figure 1 Both the upper cover acoustic black hole 1 and the lower cover acoustic black hole 5 have bolt holes 14 on their outer rings. The upper cover acoustic black hole 1 is connected to the equipment to be vibration damped by bolts, and the lower cover acoustic black hole 5 is connected to the foundation or base by bolts.

[0031] Reference Figure 1The compression-torsion unit 2 is disposed in the gap between two adjacent acoustic black hole plates. The compression-torsion unit 2 includes a ring 21 and two plate-shaped elastic members 22 fixed to the outer circumference of the ring 21. The plate-shaped elastic members 22 are arranged tangentially along the outer circumference of the ring 21, and the two plate-shaped elastic members 22 are centrally symmetrical with respect to the axis of the ring 21. The outer diameter of the ring 21 is 18 mm, the inner diameter is 15 mm, and the thickness is 3 mm; the thickness of the plate-shaped elastic members 22 is 1.5 mm. When the acoustic black hole plate is subjected to axial pressure, the elastic deformation of the plate-shaped elastic members 22 guides the ring 21 to generate torsional motion, thereby achieving energy dissipation through compression-torsion coupling.

[0032] Multiple compression-torsion units 2 are evenly spaced along the circumference of the acoustic black hole plate in the gaps between adjacent acoustic black hole plates. The ends of the two plate-shaped elastic elements 22 in each compression-torsion unit 2 are fixed to the two acoustic black hole plates respectively. The number of compression-torsion units 2 in each layer of gaps is the same, and the arrangement direction of the compression-torsion units 2 in multiple layers of gaps is parallel to the axial direction of the acoustic black hole plate. In the same layer of gaps, the compression and torsion directions of multiple compression-torsion units 2 are consistent, and the installation angles are consistent; in two adjacent layers of gaps, the compression and torsion directions of the compression-torsion units 2 are opposite, and the installation angles of the compression-torsion units 2 on both sides of the acoustic black hole plate are symmetrical about the plane of the acoustic black hole plate.

[0033] This application constructs a highly efficient composite vibration reduction structure in three-dimensional space by periodically stacking and coupling multiple acoustic black hole plates with alternating compression-torsion units in opposite directions. This periodic alternating arrangement greatly optimizes the transmission path of vibration energy. Through the successive reverse torsion of the multi-layered compression-torsion units, axial linear vibration is fully converted into torsional deformation and dissipated, significantly improving the suppression efficiency of low-frequency vibration. Simultaneously, this structure forms a periodic vibration isolation system with adjustable bandgap in the vertical direction. The coupling motion between local vibrations in the acoustic black hole region and the compression-torsion units causes the bandgap to open or close, allowing for bandgap adjustment. This enables the generation of a wide and flat bandgap in the low-frequency range, achieving excellent broadband vibration isolation in the core vibration transmission channel.

[0034] As an optional implementation, an additional acoustic black hole 4 can be added to the above structure, referring to... Figure 1 Multiple additional acoustic black holes 4 are evenly spaced along the circumference of the acoustic black hole plates in the gaps between adjacent acoustic black hole plates. The additional acoustic black holes 4 are wedge-shaped or bilobed acoustic black holes, including an outer ring 41, a region 42, and a damping region 43. The additional acoustic black holes 4 are vertically or obliquely connected between the two acoustic black hole plates; within the same layer of the gap, the installation angles of the multiple additional acoustic black holes 4 are consistent.

[0035] Building upon the existing interlayer compressive-torsional energy dissipation, the additional acoustic black hole 4 introduces extra local resonant units, capable of exciting richer vibration modes and generating coupling and synergistic effects with the bandgap of the main structure. This further broadens the vibration isolation frequency band or achieves deeper vibration reduction effects in specific frequency bands. The installation method of the additional acoustic black hole 4 configuration can be selected and adjusted according to the requirements of the target vibration reduction frequency band.

[0036] The vibration damper provided in this embodiment, which couples a compression-torsion unit with an acoustic black hole, is manufactured from stainless steel using 3D printing.

[0037] To verify the vibration reduction performance of the vibration damper coupled with an acoustic black hole provided in this embodiment, especially its effect of forming a bandgap in the low-frequency range, the following finite element model was constructed and band structure simulation was performed: This application embodiment includes an upper cover acoustic black hole 1, a middle cover acoustic black hole 3, and a lower cover acoustic black hole 5. The damping region is simulated using an equivalent viscoelastic material model. Six compression-torsion units 2 are periodically arranged along the circumferential direction between the layers. No additional acoustic black holes 4 are provided.

[0038] Comparative Example: A conventional damper (general configuration of a compression-torsion structure) of the same mass as the example was used, such as... Figure 3 As shown, the mass-equivalent comparative model uses three layers of steel rings (without acoustic black hole structure) with the same outer ring size as the cover plate of the embodiment, and the layers are connected by inclined steel columns.

[0039] Periodic boundary conditions are applied to a single periodic cell, and the band structure, i.e., the relationship between frequency and wave vector k, is calculated for the embodiments and comparative examples of this application. Figure 4 As shown in (a), the comparative mass equivalent model has no significant bandgap in the 10-1700Hz range; Figure 4 As shown in (b) of the figure, the band structure of this embodiment exhibits multiple significant full band gaps (shaded areas in the figure); the two most prominent broadband band gaps are: the first band gap: frequency range from 42Hz to 97Hz, bandwidth up to 55Hz, when wave vector k=1.25, the lower boundary mode frequency and the upper boundary mode frequency correspond to points A and B, respectively; the second band gap: frequency range from 245Hz to 297Hz, bandwidth up to 52Hz, when wave vector k=1.25, its lower boundary mode frequency and the upper boundary mode frequency correspond to points C and D, respectively.

[0040] The two band gaps mentioned above, especially the first band gap with a frequency as low as 42Hz, prove that the embodiments of this application have successfully achieved the low-frequency vibration reduction design goal below 50Hz. In addition, it can be seen that the dispersion curves corresponding to the upper and lower boundaries of the band gap are relatively flat, which indicates that the band gap has a weak dependence on the direction of the wave vector and has good stability, which is beneficial to engineering applications.

[0041] To further explore the generation mechanism of the band gap, Figure 4 (b) The vibration modes of key points A, B, C, and D are analyzed, such as Figure 5 As shown: Point A (lower boundary of the first band gap): as shown Figure 5 As shown in (a), its mode shape is mainly characterized by the overall coordinated torsional motion of the compression-torsion unit and the acoustic black hole of the intermediate cover plate. This mode marks the opening of the band gap.

[0042] Point B (upper boundary of the first band gap): as shown Figure 5 As shown in (b), its vibration mode is mainly manifested as the local vibration of the compression-torsion unit and the acoustic black hole of the middle cover plate. This local resonance mode effectively "closes" the band gap and prevents the propagation of higher frequency vibrations.

[0043] Point C (lower boundary of the second band gap): as shown Figure 5 As shown in (c), its mode shape is mainly characterized by the local vibration of the acoustic black hole of the middle cover plate, which marks the opening of the band gap.

[0044] Point D (upper boundary of the second band gap): as shown Figure 5 As shown in (d), its mode shape is mainly characterized by the torsional motion of the acoustic black hole of the upper cover plate and the acoustic black hole of the lower cover plate. This mode marks the closure of the band gap.

[0045] The above modal analysis shows that the bandgap characteristics of the vibration damper in this application originate from the synergistic effect of the local resonance effect of the acoustic black hole and the overall coupled motion mechanism of the compression-torsion unit. The combination of the two achieves precise control of the wideband bandgap.

[0046] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A vibration damper coupled to a compression-torsion unit and an acoustic black hole, characterized in that: include: At least three acoustic black holes are provided, and the multiple acoustic black holes are arranged at intervals along their own axial direction, with a gap provided between two adjacent acoustic black holes; Multiple compression and torsion units are equally spaced in the gaps along the circumference of the acoustic black hole plate; the number of compression and torsion units in each layer of the gaps is the same, and the arrangement direction of the compression and torsion units in multiple layers of the gaps is parallel to the axial direction of the acoustic black hole plate; in the same layer of the gaps, the compression and torsion directions of multiple compression and torsion units are consistent; in two adjacent layers of the gaps, the compression and torsion directions of the compression and torsion units are opposite.

2. The vibration damper coupled to an acoustic black hole by a compression-torsion unit according to claim 1, characterized in that: The spacing between two adjacent acoustic black hole plates is equal.

3. The vibration damper coupled to an acoustic black hole by a compression-torsion unit according to claim 1, characterized in that: The compression and torsion unit includes a ring and two plate-shaped elastic members fixed to the outer circumference of the ring. The plate-shaped elastic members are arranged tangentially along the outer circumference of the ring. The two plate-shaped elastic members are centrally symmetrical with respect to the axis of the ring. The ends of the two plate-shaped elastic members are respectively fixed to the two acoustic black hole plates.

4. A vibration damper coupled to an acoustic black hole by a compression-torsion unit according to claim 3, characterized in that: Within the same layer of the gap, the installation angles of multiple pressure-torsion units are consistent; within two adjacent layers of the gap, the installation angles of the pressure-torsion units are symmetrical about the plane containing the acoustic black hole plate.

5. A vibration damper coupled to an acoustic black hole by a compression-torsion unit according to claim 1, characterized in that: The acoustic black hole plate includes an outer ring, an acoustic black hole region, and a damping region arranged sequentially from the outside to the inside.

6. A vibration damper coupled to an acoustic black hole by a compression-torsion unit according to claim 5, characterized in that: Bolt holes are provided on the outer ring of the acoustic black hole plates located at both ends.

7. A vibration damper coupled to an acoustic black hole by a compression-torsion unit according to claim 6, characterized in that: One end of the acoustic black hole plate is connected to the device to be vibration damped, and the other end of the acoustic black hole plate is connected to the foundation or base.

8. A vibration damper coupled to an acoustic black hole according to any one of claims 1-7, characterized in that: It also includes multiple additional acoustic black holes, which are equally spaced along the circumference of the acoustic black hole plate in the gap.

9. A vibration damper coupled to an acoustic black hole by a compression-torsion unit according to any one of claims 8, characterized in that: The additional acoustic black hole is a wedge-shaped or bilobed acoustic black hole.

10. A vibration damper coupled to an acoustic black hole by a compression-torsion unit according to claim 8, characterized in that: The additional acoustic black hole is vertically connected between the two acoustic black hole plates, or the additional acoustic black hole is obliquely connected between the two acoustic black hole plates.

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