A sound insulation and vibration reduction partition for ship cabins containing acoustic black holes

Abstract

This utility model relates to the field of composite panel structure technology, specifically a sound insulation and vibration reduction partition for ship cabins containing acoustic black holes. The partition includes: an acoustic black hole thin plate layer, a damping material layer, and a honeycomb panel layer. Multiple sets of acoustic black hole structures are arranged in an array on the acoustic black hole thin plate layer, and the thickness of the acoustic black hole region satisfies a power law. The damping material layer forms an energy buffer interface, and its two sides are connected to the acoustic black hole thin plate layer and the honeycomb panel layer, respectively. The honeycomb panel layer is used to complete acoustic radiation impedance matching and suppression. This utility model constructs a complete acoustic vibration control chain of "vibration capture - energy dissipation - acoustic impedance matching" through gradient impedance design of each functional layer, improving sound insulation without increasing mass. It is particularly suitable for applications such as ship cabins that are weight-sensitive and require broadband noise reduction.

Description

Technical Field

[0001] This utility model relates to the field of composite panel structure technology, specifically to a sound insulation and vibration reduction partition for ship cabins containing an acoustic black hole. Background Technology

[0002] In the field of marine engineering, vibration and noise problems caused by the operation of electromechanical equipment have become a key technical bottleneck restricting the comfort and reliability of ships. Vibration energy is transmitted to the cabins through the hull structure, which not only causes health problems such as physiological fatigue and decreased concentration among passengers, but may also cause malfunctions of precision instruments, seriously affecting navigation safety. As ships develop towards larger size and higher power density, the increase in main engine power and the large-scale mechanical equipment have exacerbated the coupling effect of vibration and noise, and traditional vibration reduction and noise reduction methods face the dual challenges of soaring costs and performance bottlenecks.

[0003] As a cutting-edge technology in the field of vibration energy manipulation, an ideal acoustic black hole is one whose edge thickness gradually changes according to a power law h(x) = ε·x. m In a free wedge structure (such as a plate or beam), h(x) represents the thickness of the acoustic black hole region at point x, ε is a constant, and m is a positive rational number ≥ 2. When a perpendicularly incident curved wave propagates towards the edge of the wedge structure along a direction where the thickness gradually decreases, its cumulative phase tends to infinity near the edge, preventing the curved wave from continuing to propagate to the edge and thus avoiding wave reflection. This mechanism effectively concentrates the curved wave energy at the tip edge region of the wedge structure, forming the so-called "acoustic black hole" effect. Furthermore, by rotating a one-dimensional acoustic black hole around the edge of the wedge structure, a two-dimensional acoustic black hole structure can be constructed. The "acoustic black hole" structure can concentrate the curved wave energy at the edge of a one-dimensional wedge structure or the center of a two-dimensional acoustic black hole, effectively suppressing vibration. However, in actual manufacturing, it is difficult to achieve a structural thickness that strictly follows a power law to change to zero, easily resulting in truncation at the tip. Studies have shown that even a small local thickness can cause a sharp increase in the structure's reflection coefficient, weakening its energy concentration effect. Attaching damping materials to the acoustic black hole region can effectively reduce the reflection coefficient. Attaching a high-density mass block as an oscillator to the central region of the acoustic black hole can effectively absorb and dissipate the energy gathered by the acoustic black hole, further achieving the effect of vibration reduction and noise reduction.

[0004] Phononic crystals are a new physical concept proposed in condensed matter physics based on the research of photonic crystals. Locally resonant phononic crystals possess a low-frequency bandgap, within which vibrations can be effectively attenuated, offering significant advantages in low-frequency vibration reduction applications. However, the bandgap of locally resonant phononic crystals is concentrated in a very narrow frequency range, making it difficult to achieve good results across multiple frequency bands simultaneously. Vibration attenuation within the bandgap is affected by the structure of the phononic crystal; existing phononic crystal vibration isolators, limited by thickness, do not provide ideal isolation performance at small periods, and the isolation frequency range is difficult to adjust.

[0005] Patent application CN111851332A discloses a trackside sound barrier based on acoustic black holes. This solution utilizes the acoustic black hole effect to reduce wheel-rail noise to a certain extent without altering the track structure, exhibiting some energy absorption and noise reduction effects. However, the damping material attached solely to the black hole region has limited dissipation effect on the vibrational energy concentrated at the center of the acoustic black hole. Especially in practical applications, the presence of a cutoff causes undissipated energy at the center of the acoustic black hole to be reflected away, resulting in limited vibration reduction and noise reduction effects. Furthermore, the effective vibration reduction and noise reduction frequency band of a plate structure employing only one set of acoustic black holes is limited, working only on certain mid-to-high frequency bands.

[0006] In summary, how to effectively suppress broadband vibration noise and achieve efficient sound insulation has become a core technical challenge that urgently needs to be solved in this field. Utility Model Content

[0007] The purpose of this utility model is to provide a sound insulation and vibration reduction partition for ship cabins containing an acoustic black hole in order to solve at least one of the above-mentioned technical problems.

[0008] This utility model achieves the above objectives through the following technical solutions:

[0009] A sound insulation and vibration reduction partition for ship cabins containing an acoustic black hole includes: an acoustic black hole thin plate layer, a damping material layer, and a honeycomb plate layer;

[0010] The acoustic black hole thin plate layer has multiple sets of acoustic black hole structures arranged in an array, and the thickness of the acoustic black hole region satisfies the power law.

[0011] The damping material layer is used to form an energy buffer interface, and the two sides of the damping material layer are respectively connected to the acoustic black hole thin plate layer and the honeycomb plate layer;

[0012] The honeycomb panel is used to achieve acoustic radiation impedance matching and suppression.

[0013] Furthermore, the acoustic black hole thin plate layer has a high-density oscillator with radius R1 and a damping material with radius R2 coaxially attached to the center of the acoustic black hole region, where R1 < R2.

[0014] Furthermore, the high-density oscillator material is copper, the damping material is a polymer, and the high-density oscillator material and the damping material are combined to form a localized resonant phonon crystal cell unit.

[0015] Furthermore, the acoustic black hole structure is provided in two sets, with different radii and different center-to-center distances between the two sets of acoustic black holes.

[0016] Furthermore, the two sets of acoustic black holes are arranged alternately.

[0017] Furthermore, the damping material layer is an aerogel felt layer.

[0018] Furthermore, the honeycomb panel layer comprises: a thin plate layer and a honeycomb layer;

[0019] The honeycomb layer is composed of a honeycomb with a regular hexagonal cavity structure, and the cavities of the honeycomb are filled with a damping filler material.

[0020] Furthermore, the thickness of the thin plate layer is 1 / 5 of the thickness of the honeycomb layer;

[0021] The height of the honeycomb is greater than twice the thickness of the honeycomb panel.

[0022] Furthermore, the thickness of the damping material layer is not less than twice the thickness of the acoustic black hole thin plate layer.

[0023] Furthermore, the acoustic black hole thin plate layer, the damping material layer, and the honeycomb plate layer are all the same in size and shape.

[0024] The beneficial effects of this utility model are as follows:

[0025] This invention achieves efficient control of broadband noise by synergistically integrating the acoustic black hole effect, local resonant phonon crystal mechanism, damping energy dissipation, and honeycomb sound insulation technology. An energy focusing network constructed from multiple sets of variable-parameter acoustic black hole arrays, combined with a local resonant unit formed by a central copper oscillator and peripheral damping materials, efficiently converts vibration energy above 500Hz and effectively suppresses vibration amplitude in the 300-500Hz frequency range. The asymmetric periodic phonon crystal layout overcomes the bottleneck of traditional acoustic black hole technology in low-frequency sound insulation, achieving improved sound insulation in the low-frequency range. The composite impedance matching design of the aerogel felt layer and the filled honeycomb structure enhances airborne sound insulation across the entire frequency range, while the nanoporous structure of the aerogel felt imparts fire-resistant properties to the partition. This invention overcomes the frequency limitations of single noise reduction methods through a multi-physics coupling mechanism, making it particularly suitable for engineering scenarios such as ship cabins that have combined requirements for fire prevention, lightweighting, and broadband noise reduction. Attached Figure Description

[0026] Figure 1 This is a side view schematic diagram of a ship cabin sound insulation and vibration reduction partition structure containing an acoustic black hole, according to one embodiment of the present invention.

[0027] Figure 2 This is a front view schematic diagram of a ship cabin sound insulation and vibration reduction partition structure containing an acoustic black hole, according to one embodiment of the present invention.

[0028] Figure 3 This is a schematic diagram of an acoustic black hole thin plate layer according to one embodiment of the present invention;

[0029] Figure 4 This is a magnified schematic diagram of an acoustic black hole according to one embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the damping material layer according to one embodiment of the present invention;

[0031] Figure 6 This is a schematic diagram of a honeycomb panel layer according to one embodiment of the present invention;

[0032] Figure 7 This is a cross-sectional view of a localized resonant phononic crystal cell unit according to one embodiment of the present invention. Detailed Implementation

[0033] The present invention will now be discussed with reference to exemplary embodiments. It should be understood that the described embodiments are merely intended to enable those skilled in the art to better understand and thus implement the present invention, and are not intended to imply any limitation on the scope of the present invention.

[0034] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment".

[0035] Example 1

[0036] Figure 1 This is a side view schematic diagram of a ship cabin sound insulation and vibration reduction partition structure containing an acoustic black hole, according to one embodiment of the present invention. Figure 2 This is a front view schematic diagram of a ship cabin sound insulation and vibration reduction partition structure containing an acoustic black hole, according to one embodiment of the present invention. Figure 3 This is a schematic diagram of an acoustic black hole thin plate layer according to one embodiment of the present invention; Figure 4 This is a magnified schematic diagram of an acoustic black hole according to one embodiment of the present invention; Figure 5 This is a schematic diagram of the damping material layer according to one embodiment of the present invention; Figure 6 This is a schematic diagram of a honeycomb panel layer according to one embodiment of the present invention; Figure 7 This is a cross-sectional view of a localized resonant phonon crystal cell unit according to one embodiment of the present invention. Figure 1-7 As shown, according to one embodiment of the present invention, a sound insulation and vibration reduction partition for ship cabins containing an acoustic black hole includes: an acoustic black hole thin plate layer 1, a damping material layer 2, and a honeycomb plate layer 3.

[0037] Multiple acoustic black hole structures are arranged in an array on the acoustic black hole thin plate layer 1, and the thickness of the acoustic black hole region satisfies the power law.

[0038] The damping material layer 2 is used to form an energy buffer interface, and the two sides of the damping material layer 2 are connected to the acoustic black hole thin plate layer 1 and the honeycomb plate layer 3, respectively.

[0039] The honeycomb layer 3 is used to complete the acoustic radiation impedance matching and suppression.

[0040] Preferably, the acoustic black hole thin plate layer 1, the damping material layer 2, and the honeycomb plate layer 3 are all the same in size and shape.

[0041] In this embodiment, a sound insulation and vibration reduction partition for ship cabins containing an acoustic black hole is proposed. Vibration and noise control of the ship cabins are achieved through the synergistic effect of multiple functional materials. The structure is composed of an acoustic black hole thin plate layer 1, a damping material layer 2, and a honeycomb plate layer 3, which are sequentially composited. Each layer is conformally connected at the interface through physical or chemical means to form an acoustic-vibration coupling suppression system with gradient impedance characteristics.

[0042] The acoustic black hole thin-plate layer 1 adopts an arrayed power-law thickness distribution design. Its core principle lies in utilizing the structural thickness according to a power function (h(x)=ε·x). m The acoustic black hole effect is formed by a continuous decrease in thickness (m≥2). The acoustic black hole thin plate layer 1 includes a region of uniform thickness and an acoustic black hole region. When vibration waves or sound waves propagate from the acoustic black hole thin plate layer 1 to the acoustic black hole region, the group velocity of the wave gradually decreases with decreasing thickness, resulting in an energy accumulation effect at the black hole end. This geometric structural characteristic enables the incident wave to focus energy along its propagation path, and the arrayed arrangement can expand the effective operating frequency band. While maintaining overall stiffness, this structure can achieve the redistribution of vibration energy in a specific frequency band (usually mid-to-high frequency) by controlling the wave propagation path.

[0043] The damping material layer 2 serves as an energy conversion interface. This layer converts mechanical vibration energy into thermal energy through a viscoelastic damping mechanism. Its shear deformation characteristics and the strain concentration effect of the black hole structure form a coupled dissipation, effectively breaking the energy transfer chain of structural vibration-acoustic radiation. The introduction of the damping material layer 2 can reduce the system's quality factor and significantly shorten the vibration decay time constant.

[0044] The honeycomb layer 3 employs a micro-perforated honeycomb core structure, whose hexagonal cells form a multi-channel network that enables multiple scattering and viscous loss of sound waves. This layer achieves acoustic radiation impedance matching through geometric topology optimization, with its characteristic impedance falling between that of fluid media (air / water) and solid structures, reducing the sound wave reflection coefficient at the interface. The low bending stiffness of the honeycomb structure also provides additional vibration decoupling, forming a stiffness gradient transition with the upper damping material layer 2, thus avoiding secondary noise radiation caused by abrupt changes in material parameters.

[0045] This invention constructs a complete acoustic vibration control chain of "vibration capture - energy dissipation - acoustic impedance matching" through gradient impedance design of each functional layer. The acoustic black hole layer realizes the spatial redistribution of energy, the damping material layer completes the energy form conversion, and the honeycomb panel layer realizes sound wave terminal absorption. The synergistic effect of the three can simultaneously suppress the propagation of structural noise and airborne noise. This invention can improve sound insulation without increasing the system mass, making it particularly suitable for applications such as ship cabins that are weight-sensitive and require broadband noise reduction.

[0046] According to one embodiment of the present invention, a high-density oscillator with radius R1 and a damping material with radius R2 are coaxially attached to the center of the acoustic black hole region of the acoustic black hole thin plate layer 1, where R1 < R2.

[0047] Preferably, the high-density oscillator material is copper, and the damping material is a polymer. The high-density oscillator material and the damping material are combined to form a localized resonant phonon crystal cell unit.

[0048] In this embodiment, a localized resonant phonon crystal cell unit is introduced based on the geometric sound-absorbing structure of the acoustic black hole thin plate layer 1, forming a multi-level control mechanism for vibration energy. This structure coaxially nests a high-density copper oscillator and a polymer damping ring at the center of the acoustic black hole region. The density of the high-density oscillator is higher than the density of the damping material, and the thickness of the upper high-density oscillator is greater than or equal to the thickness of the lower low-density damping material. A mass-spring-damping composite system is constructed through a dimensional design where R1 < R2: the copper oscillator provides inertial mass as a localized resonator, and its radius R1 precisely matches the minimum thickness region at the end of the acoustic black hole, utilizing the material density difference to form a significant abrupt change in acoustic impedance. The outer polymer damping ring, through a covering design where R2 > R1, serves both as a confining damping layer absorbing the vibration energy of the copper oscillator and as the elastic matrix of the phonon crystal; its low shear modulus characteristics effectively extend the vibration decay time constant.

[0049] Wideband vibration control is achieved through the synergistic effect of acoustic black hole effect and local resonance mechanism: the power-law thickness distribution of acoustic black hole causes the incident wave to generate progressive energy accumulation during propagation. When the wavefront reaches the center of the black hole, the high-density copper oscillator transforms macroscopic vibration into microscopic particle displacement through mass loading effect, triggering the viscoelastic dissipation mechanism of polymer damping ring; at the same time, the density difference between copper oscillator and matrix material forms Bragg scattering interface, which couples with local resonance mode to produce bandgap modulation effect, so that the effective sound insulation frequency band can be extended to low frequency while maintaining structural compactness.

[0050] The composite control mechanism of this utility model has three technical advantages: (1) Enhanced energy focusing effect: The geometric sound absorption of the acoustic black hole and the mass vibration absorption of local resonance form a dual energy capture, which enhances the concentration of vibration energy; (2) Optimized frequency response characteristics: By adjusting the ratio of the radius R1 of the copper oscillator to the radius R2 of the damping material, the bandgap center frequency can be customized to cover the fundamental frequency of the ship's main engine vibration and its harmonic components; (3) Enhanced structural stability: The radial constraint of the damping material can suppress the displacement of the copper oscillator under high-frequency vibration, avoiding the fatigue failure problem that is prone to occur in traditional local resonance structures. This utility model provides an innovative solution for the control of low-frequency line spectrum noise in ship cabins through the deep integration of geometric sound absorption and dynamic vibration absorption.

[0051] According to one embodiment of this utility model, the acoustic black hole structure is provided in two sets, the two sets of acoustic black holes have different radii and different center distances.

[0052] Preferably, the two sets of acoustic black holes are arranged alternately.

[0053] In this embodiment, a multi-band vibration energy coordinated control mechanism is constructed by setting two sets of acoustic black hole structures with different geometric parameters on the acoustic black hole thin plate layer 1. The core of this technical solution lies in the use of an asymmetric periodic arrangement strategy: the first set of acoustic black holes adopts a large radius r1 design, and its center-to-center spacing D1 meets the wavelength scale, mainly targeting the control of low-frequency structural noise; the second set of acoustic black holes adopts a small radius r2 (r2 < r1), and its center-to-center spacing D2 (D2 ≠ D1) is optimized to match the wavelength characteristics of mid-to-high frequency air noise. The two sets of acoustic black hole structures are arranged alternately to form a two-dimensional periodic lattice, and the decoupling control of broadband vibration modes is achieved through the spatial Fourier transform characteristics.

[0054] The power-law thickness distribution of large-radius acoustic black holes effectively reduces the phase velocity of low-frequency curved waves, causing significant phase delays in long-wavelength vibrations within the structure. Small-radius acoustic black holes, on the other hand, enhance the scattering effect of mid-to-high frequency sound waves through their high-curvature surfaces. The asymmetric center-to-center distance design breaks the Bragg scattering conditions of traditional periodic structures, avoiding the sound insulation trough caused by modal superposition. In particular, by optimizing the ratio of D1 to D2, the staggered arrangement of low-frequency resonance peaks and high-frequency anti-resonance peaks can be achieved. The staggered arrangement of the two sets of acoustic black holes forms a multi-scale energy trap network. After the incident wave undergoes initial attenuation by the first-stage large-radius black hole, the residual energy is refocused in the region of the second-stage small-radius acoustic black hole. Combined with the viscoelastic dissipation of the damping material layer 2, a cascaded energy attenuation channel is formed.

[0055] This invention broadens the effective frequency band of traditional single-mode acoustic black holes to two orders of magnitude through dual-mode parameter combination, with particularly outstanding performance in the control of the fundamental frequency and harmonic components of ship main engines; the asymmetrical arrangement gives the structure different impedance characteristics in the radial and tangential directions, allowing for customized design for the direction of propeller excitation force in ship cabins; compared with a single large-size acoustic black hole structure, the dual-mode layout reduces the overall mass while maintaining sound insulation performance, which is more in line with the requirements of lightweight ship design.

[0056] According to one embodiment of the present invention, the damping material layer 2 is an aerogel felt layer.

[0057] Preferably, the aerogel felt layer is attached between the acoustic black hole thin plate layer 1 and the honeycomb plate layer 3 by means of adhesive bonding.

[0058] In this embodiment, aerogel felt is used as the damping material layer 2. Its unique nanoporous structure, together with the acoustic black hole thin plate layer 1 and the honeycomb plate layer 3, forms a viscoelastic constraint damping system. The aerogel felt layer achieves conformal interface connection through full-planar bonding. Its high-porosity nanoframework effectively disperses the vibrational energy focused by the acoustic black hole structure, achieving energy conversion through a dual mechanism of inter-pore air viscous loss and polymer matrix shear deformation. While maintaining ultra-low density, the damping temperature range can be controlled by changing the pore structure parameters, maintaining a stable loss factor over a wide temperature range. Its three-dimensional interconnected nanonetwork structure can also suppress flexural wave reflection from the honeycomb plate layer 3, forming multiple sound wave scattering paths.

[0059] The aerogel felt layer of this invention improves the sound insulation of the partition while reducing the surface density of the structure; its nano-damping properties shorten the vibration decay time constant and significantly suppress high-frequency continuous spectrum noise in the ship's cabin.

[0060] According to one embodiment of the present invention, the honeycomb panel 3 includes: a thin plate layer and a honeycomb layer;

[0061] The honeycomb layer is composed of a honeycomb with a regular hexagonal cavity structure, and the cavities of the honeycomb are filled with damping filler material.

[0062] Preferably, the thickness of the thin plate layer is 1 / 5 of the thickness of the honeycomb layer;

[0063] The height of the honeycomb is more than twice the thickness of the honeycomb panel layer 3.

[0064] In this embodiment, the structure of the honeycomb panel 3 is further described. The honeycomb panel 3 is a filled honeycomb damping composite structure. By setting a regular hexagonal cavity honeycomb layer in the honeycomb panel 3 and injecting polymer damping filler material into the honeycomb cavity, a "rigid skeleton-flexible damping" composite system is formed. The height of the honeycomb constituting the honeycomb layer is more than twice the thickness of the honeycomb panel 3. Its regular hexagonal topology provides isotropic bending stiffness, while the polymer filler in the cavity absorbs structural vibration energy through a viscoelastic deformation mechanism, especially generating a significant shear dissipation effect during the deformation of the honeycomb wall. The combined structure of the thin plate layer and the honeycomb layer transfers interfacial stress, keeping the damping filler material in the efficient working strain zone at all times. At the same time, the honeycomb height design can effectively extend the propagation path of sound waves in the microporous structure and enhance the viscous loss effect.

[0065] The honeycomb panel design of this invention improves the sound insulation of the partition while reducing the surface density; the damping filling design increases the critical buckling load of the honeycomb structure, significantly enhancing the structural stability under complex sea conditions.

[0066] According to one embodiment of the present invention, the thickness of the damping material layer 2 is not less than twice the thickness of the acoustic black hole thin plate layer 1.

[0067] In this embodiment, the performance of the acoustic-vibration coupling system is optimized by precisely controlling the thickness parameters of each layer. The damping material layer 2 is designed to be twice or more the thickness of the acoustic black hole thin plate layer 1. By utilizing the nonlinear relationship between the strain energy density and thickness of the viscoelastic material, the working strain zone of the damping layer is extended to the high strain gradient region at the end of the black hole structure while maintaining the interface shear stress matching, which significantly improves the efficiency of the constraint damping treatment. The honeycomb plate layer 3 has a honeycomb height that is more than twice the thickness of the honeycomb plate layer 3 to form a gradient impedance interface. Through the coupling of the cavity resonance effect and the film vibration mode, multiple sound wave scattering paths are generated during the bending deformation of the honeycomb wall, while maintaining the structural surface density comparable to the traditional scheme.

[0068] The thickness matching design of this utility model improves the sound insulation of the partition, the optimized thickness of the damping material layer improves the vibration energy dissipation efficiency, and the honeycomb height design reduces the sound radiation efficiency while maintaining structural rigidity. It is particularly suitable for the dual requirements of lightweight and efficient noise reduction in ship cabins.

[0069] This invention utilizes a combination of acoustic black holes, localized resonant phonon crystals, and damping sound-absorbing layers and honeycomb panel sound insulation layers to significantly reduce vibrations and noise over a wide frequency range, achieving highly efficient sound insulation.

[0070] Example 2

[0071] like Figure 1-7According to one embodiment of the present invention, a ship cabin sound insulation and vibration reduction partition containing an acoustic black hole is used to separate the various cabins of a ship and at the same time isolate the sound transmission between the cabins, comprising: an acoustic black hole thin plate layer 1, a damping material layer 2, and a honeycomb plate layer 3.

[0072] The acoustic black hole thin plate layer 1 consists of an acoustic black hole region and a uniform region, with a high-density mass block and damping material attached to the center of the acoustic black hole. The acoustic black hole thin plate layer 1 is made of aluminum alloy and is rectangular in shape. The thickness of the acoustic black hole region satisfies a power law: h(x) = εx m The density decreases, and there is a truncation at the center of the acoustic black hole, with a thickness of 0.5 mm. A high-density oscillator is attached to the center of the acoustic black hole region, and damping material is attached to the acoustic black hole region around the high-density oscillator.

[0073] The two sets of acoustic black holes in the acoustic black hole thin plate layer 1 have different radii. The center-to-center distance within each set of acoustic black hole regions is a constant value, and they are arranged in a rectangular array at intervals. The acoustic black holes are fabricated by stamping or 3D printing. The high-density oscillator material at the center of the acoustic black hole region is copper. The region filled with the high-density oscillator has a radius of 0.008m and a thickness of 0.001m. The high-density oscillator is attached to the center of the acoustic black hole region by adhesive bonding. The damping material attached to the center of the acoustic black hole region is a polymer. The damping material has a radius of 0.08m and a thickness of 0.001m and is attached to the acoustic black hole region by adhesive bonding.

[0074] The damping material layer 2 is made of aerogel felt. The shape and size of the damping material layer 2 are the same as those of the acoustic black hole thin plate layer 1, and the thickness of the damping material layer 2 is twice that of the acoustic black hole thin plate layer 1. The damping material layer 2 made of aerogel felt is attached between the acoustic black hole thin plate layer 1 and the honeycomb plate layer 3 by adhesive bonding.

[0075] The honeycomb panel layer 3 is composed of honeycomb panels and damping filler material.

[0076] The honeycomb panel 3 includes a thin plate layer and a honeycomb layer. The thickness of the thin plate layer is 1 / 5 of the thickness of the honeycomb layer, and the honeycomb layer is filled with damping filler material.

[0077] The honeycomb panel 3 consists of two parts: a honeycomb layer and a thin plate layer, which are connected by welding. The honeycomb layer has a regular hexagonal cavity structure, and the cavity is filled with a damping filler material, which is a polymer.

[0078] In this embodiment, a sound insulation and vibration reduction bulkhead for ship cabins incorporating an acoustic black hole, integrating a multi-dimensional vibration control mechanism, is proposed. The bulkhead adopts a three-layer composite structure to achieve full-process control from vibration energy capture to sound radiation suppression. The bulkhead is composed of an acoustic black hole thin plate layer 1, a damping material layer 2, and a honeycomb plate layer 3, with each layer forming a synergistic system through physical coupling.

[0079] The acoustic black hole thin-plate layer 1 is constructed using an aluminum alloy substrate to create a dual-modal acoustic black hole array. The acoustic black hole thin-plate layer 1 consists of a uniform region and acoustic black hole regions with thicknesses varying according to a power law. A 0.5mm truncation is maintained at the end of the wedge-shaped structure of the acoustic black hole regions to avoid manufacturing defects. To compensate for energy reflection caused by the truncation, a dual-component energy processing system is integrated in the central region of the black hole: a 16mm diameter, 1mm thick copper high-density oscillator is embedded at the center, absorbing vibration energy in a specific frequency band using a local resonance mechanism; a 160mm diameter, 1mm thick polymer damping material ring is placed around the high-density oscillator, converting residual mechanical energy into heat energy through a viscoelastic dissipation mechanism. Two sets of acoustic black hole units with different radii (the radius difference design is based on the typical vibration frequency distribution of ships) are periodically arranged in a rectangular array. The unit spacing is optimized to avoid modal coupling; this asymmetric layout expands the effective operating frequency band.

[0080] The damping material layer 2 uses aerogel felt to construct the energy buffer interface, and its thickness is designed to be twice that of the acoustic black hole thin plate layer 1 to provide sufficient deformation space. This layer achieves broadband damping characteristics through a molecular-level porous structure, forming a viscous damping field in the vibration transmission path. In particular, the aerogel felt layer and the interfaces between the upper and lower layers are chemically bonded using a special adhesive to ensure that secondary noise is not generated due to interface slippage during the interlayer transmission of vibrational energy.

[0081] Honeycomb layer 3 serves as a sound radiation barrier, employing a regular hexagonal honeycomb sandwich structure, with its equivalent density controlled by honeycomb geometric parameters. The honeycomb cavities are filled with polymer damping material, forming a mass-spring-damping composite system: the honeycomb walls act as elastic elements, while the cavity damping material provides an energy dissipation mechanism. This combined structure maintains structural stiffness while reducing weight. The honeycomb layer and the thin plate layer are metallurgically bonded using laser welding, with the weld points arranged in a honeycomb pattern to balance stress distribution.

[0082] This invention employs a multi-physics coupling mechanism: the acoustic black hole thin plate layer first achieves spatial focusing of vibrational energy through geometrical gradient; the high-density oscillator selectively absorbs the focused energy in the frequency domain; the residual energy is viscously dissipated by the damping material layer, and finally, the honeycomb plate layer completes the acoustic radiation impedance matching suppression. This cascaded energy processing flow breaks through the frequency band limitations of traditional single-layer structures, achieving end-to-end vibration control from bending wave manipulation to acoustic radiation suppression while maintaining structural compactness.

[0083] Example 3

[0084] According to one embodiment of the present invention, a design method for a ship cabin sound insulation and vibration damping partition containing an acoustic black hole is provided for manufacturing any of the ship cabin sound insulation and vibration damping partitions containing an acoustic black hole according to the present invention. The method includes the following steps:

[0085] Step S102: Measure the vibration and noise signals of the sound source using a vibration and noise testing system, and analyze the measurement results to obtain basic data; determine the starting frequency of the required acoustic black hole and the minimum frequency that meets the smoothness requirements based on the basic data.

[0086] Step S104: Based on the starting frequency and the lowest frequency that meets the smoothness requirements, determine the minimum radius r of the required acoustic black hole in combination with the application scenario of the partition.

[0087] Step S106: Using the minimum radius r as the minimum value and 0.1m as the step size, establish no less than 3 sets of acoustic black hole thin plate models using finite element software for calculation, and select at least two sets of target calculation cases from the acoustic black hole thin plate models that correspond to the effective frequency bands and the acoustic vibration line spectrum positions of the sound source; based on the target calculation cases, determine the radius of each set of acoustic black holes;

[0088] Step S108: Obtain the thickness R0 of the damping material attached to the center of the acoustic black hole region based on the following formula;

[0089]

[0090] Where ω is the frequency; ρ is the density of the acoustic black hole; v is the Poisson's ratio of the acoustic black hole; and ε is the power-law expression h(x) = ε·x m The coefficient; E is the Young's modulus of the acoustic black hole plate; R t R is the cutoff radius; i η is the radius of the acoustic black hole; comp (r) is the equivalent loss factor; r is the radius of the desired acoustic black hole; η D E is the loss factor of the damping material. D h is the Young's modulus of the damping material. D E represents the thickness of the damping layer. w h is the elastic modulus in complex form of the acoustic black hole structure. w The thickness of the acoustic black hole region;

[0091] Step S110: Based on the principle of local resonant phonon crystal, determine the array distance of each group of acoustic black hole structures under the premise of being able to weaken the preset degree of sound and vibration amplitude of the low-frequency sound source.

[0092] Step S112: Based on the thickness of the acoustic black hole thin plate layer 1, and according to the size of the cabin space and sound insulation requirements, the thickness of the damping material layer 2 and the honeycomb plate layer 3 are designed with the least amount of cabin space occupied.

[0093] This embodiment proposes a design method for a sound insulation and vibration reduction bulkhead in a ship cabin containing an acoustic black hole, achieving customized acoustic and vibration control through multi-physics coupling analysis and parameter optimization. The method first uses a vibration and noise testing system to scan the target sound source (mechanical equipment) across the entire frequency band, obtaining the vibration acceleration level and noise spectrum characteristics, thereby determining the start and end frequency boundaries of the acoustic black hole structure. Based on the power-law thickness distribution theory, a finite element model cluster is established, generating multiple sets of radius-parameterized models with a step size of 0.1m. Candidate schemes with a line spectrum overlap exceeding a set threshold with the sound source are selected through modal analysis and harmonic response calculation. Combining the dynamic mechanical parameters of the damping material, an equivalent loss factor model is used to calculate the optimal damping layer thickness, ensuring phase matching between viscoelastic dissipation and structural vibration. The local resonant phonon crystal theory is introduced, and the periodic parameters of the acoustic black hole array are determined through band structure calculation, enabling coupling suppression between the Bragg scattering bandgap and the target low-frequency resonance peak. Finally, a multi-objective optimization model is established based on cabin space constraints, achieving coordinated optimization of structural thickness and surface density while ensuring sound insulation.

[0094] This invention utilizes a data-driven forward design process to achieve deep adaptation between the sound insulation structure and the characteristics of the sound source. While maintaining the lightweight level of traditional solutions, it expands the effective frequency band of acoustic black holes, and in particular, enhances the low-frequency line spectrum suppression capability through array periodic control. Parametric modeling and multi-objective optimization techniques shorten the design cycle, making it particularly suitable for customized noise reduction needs in complex acoustic environments such as ship propulsion systems.

[0095] Example 4

[0096] According to one embodiment of this utility model, a design method for a sound insulation and vibration reduction partition for a ship's cabin containing an acoustic black hole includes the following steps:

[0097] Step S201: Use a vibration and noise testing system to measure the vibration and noise signals of the sound source (mechanical equipment) and summarize its characteristics to facilitate the targeted design of the partition structure.

[0098] Step S202: Based on the acoustic and vibration characteristics of the sound source, determine the minimum frequency of the acoustic and vibration signals to be addressed, and the required initial frequency ω of the acoustic black hole. c1 For the acoustic black hole to meet the smoothness requirement, the value must be less than this: ω ≥ ω c2 Determine an appropriate coefficient ε.

[0099] in,

[0100] Where h is the thickness of the uniform region of the acoustic black hole; E is the Young's modulus of the acoustic black hole plate; ρ is the density of the acoustic black hole plate; v is the Poisson's ratio of the acoustic black hole plate; and ε is the power-law expression h(x) = ε·x. m The coefficient of ω, where ε is a constant; c1 ω is the starting frequency; c2 The minimum frequency required to meet smoothness requirements.

[0101] Step S203, based on the principle of acoustic black holes and the required ω c1 and ω c2 The size of the black hole is used to calculate the radius r of the required acoustic black hole.

[0102] In step S204, using the acoustic black hole radius r determined in step S203 as the minimum value and a step size of 0.1m, at least three sets of acoustic black hole thin plate models are established using finite element software for calculation, and at least two sets of calculation examples corresponding to the frequency bands with larger amplitudes of the sound source's acoustic vibration line spectrum are selected from them.

[0103] Step S205: Based on the selected example, select appropriate r1 and r2 as the radii of the two sets of acoustic black holes in the acoustic black hole thin plate layer 1, respectively.

[0104] Step S206: Select a suitable damping layer thickness according to the following formula:

[0105]

[0106] Among them, R t R is the cutoff radius. i Let η be the radius of the acoustic black hole. comp (r) is the equivalent loss factor, calculated using the following formula:

[0107]

[0108] Among them, E D h is the Young's modulus of the damping material. D η is the thickness of the damping layer. D E is the loss factor of the damping material. w h is the elastic modulus in complex form of the acoustic black hole structure. w The thickness of the acoustic black hole region.

[0109] Step S207: Based on the principle of local resonant phonon crystals, determine the relative distance of the acoustic black hole structure array under the premise of being able to reduce the noise at low frequencies with high amplitude of sound and vibration of the sound source below the cutoff frequency of the acoustic black hole structure.

[0110] Step S208: Based on the size of the cabin space and the sound insulation requirements, design the thickness of the damping layer and the thickness of the honeycomb panel layer while taking up as little cabin space as possible. In principle, the thickness of the damping layer should not be less than twice that of the acoustic black hole panel.

[0111] This invention achieves full-frequency coordinated control of vibration and noise through multi-physics coupling design, and its technical advantages are reflected in the following aspects:

[0112] Frequency-domain adaptive vibration energy manipulation: Based on the power-law thickness gradient structure of acoustic black holes, energy focusing effect on bending waves in the mid-to-high frequency band above 500Hz is achieved. Through the design of a dual-mode acoustic black hole array (radii r1 and r2 correspond to different characteristic frequencies), the operating frequency band of each black hole unit is precisely matched with the line spectrum frequencies of typical sound sources such as ship main engines and auxiliary engines. High-density copper oscillators serve as local resonant units, and their natural frequencies are optimized to absorb specific frequency band energy converged by the acoustic black holes. Meanwhile, polymer damping rings handle residual mechanical energy through viscoelastic dissipation mechanisms, forming a hierarchical processing chain of "energy capture - frequency band screening - mechanical dissipation".

[0113] Low-frequency bandgap extension mechanism: For the low-frequency band below 300Hz, a local resonant phonon crystal is constructed by periodic array of acoustic black hole structures, so that Bragg scattering and local resonance effects generate a coupling bandgap, which effectively makes up for the performance limitations of single black hole structures in the low-frequency band.

[0114] Multi-level damping dissipation system: The aerogel felt damping layer achieves broadband damping characteristics through its microporous structure, ensuring continuous viscous dissipation. The honeycomb panel layer adopts a regular hexagonal honeycomb sandwich structure, which, while ensuring structural stiffness, achieves secondary energy dissipation through polymer damping filling. This three-level damping system (local damping ring - interlayer damping layer - honeycomb damping core) significantly improves structural damping compared to traditional bulkhead structures. In terms of spatial constraints, the total thickness is controlled to meet ship compartment bulkhead installation specifications. The aerogel felt layer has fireproof and thermal insulation functions, further enhancing the performance of the bulkhead.

[0115] This invention comprehensively utilizes the acoustic black hole principle, the local resonant phonon crystal principle, and the damping and honeycomb sound insulation principles to effectively and significantly reduce noise in low, medium, and high frequency bands.

[0116] By setting up multiple sets of acoustic black hole structures, vibration and noise energy across various frequency bands is effectively concentrated. High-density mass blocks are used as oscillators, and damping materials are bonded to dissipate the concentrated energy. This method demonstrates a significant effect in reducing vibration and noise above 500Hz and a notable effect in reducing vibration and noise within the 300Hz-500Hz range. By periodically arraying the acoustic black hole structures to form a localized resonant phonon crystal structure, the drawback of poor low-frequency performance of acoustic black hole structures is overcome, resulting in significant sound insulation across the entire frequency range. Furthermore, the sound insulation effects of the aerogel felt layer and honeycomb panel layer are combined to further reduce noise transmission significantly. The presence of the aerogel felt layer also provides the partition with high fire resistance, making it suitable for sound insulation in ship cabins and other facilities and equipment, demonstrating high engineering application value.

[0117] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the method described above can be referred to the corresponding process in the aforementioned partition embodiment, and will not be repeated here.

[0118] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the utility model involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

[0119] It should be understood that the sequence number of each step in the utility model content and embodiments does not absolutely mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the utility model embodiments.

Claims

1. A ship cabin soundproofing and vibration damping partition comprising an acoustic black hole, characterized in that, include: Acoustic black hole thin plate layer (1), damping material layer (2), honeycomb plate layer (3); Multiple acoustic black hole structures are arranged in an array on the acoustic black hole thin plate layer (1), and the thickness of the acoustic black hole region satisfies the power law. The damping material layer (2) is used to form an energy buffer interface, and the two sides of the damping material layer (2) are respectively connected to the acoustic black hole thin plate layer (1) and the honeycomb plate layer (3); The honeycomb panel (3) is used to complete the acoustic radiation impedance matching suppression.

2. The acoustic black hole containing ship cabin soundproofing and vibration damping panel of claim 1, wherein: The acoustic black hole thin plate (1) has a high-density oscillator with radius R1 and a damping material with radius R2 coaxially attached to the center of the acoustic black hole region, where R1 < R2.

3. The acoustic black hole containing ship cabin soundproofing and vibration damping panel of claim 2, wherein: The high-density oscillator material is copper, and the damping material is a polymer. The high-density oscillator material and the damping material are combined to form a localized resonant phonon crystal cell unit.

4. The acoustic black hole containing ship cabin soundproofing and vibration damping panel of claim 1, wherein: The acoustic black hole structure is configured in two sets, with different radii and different center-to-center distances.

5. The acoustic black hole containing ship cabin soundproofing and vibration damping panel of claim 4, wherein: Two sets of acoustic black holes are arranged alternately.

6. The acoustic black hole containing ship cabin soundproofing and vibration damping panel of claim 1, wherein: The damping material layer (2) is an aerogel felt layer.

7. The acoustic black hole containing ship cabin soundproofing and vibration damping panel of claim 1, wherein, The honeycomb panel (3) includes: a thin plate layer and a honeycomb layer; The honeycomb layer is composed of a honeycomb with a regular hexagonal cavity structure, and the cavities of the honeycomb are filled with a damping filler material.

8. The acoustic black hole containing ship cabin soundproofing and vibration damping panel of claim 7, wherein: The thickness of the thin plate layer is 1 / 5 of the thickness of the honeycomb layer; The height of the honeycomb is greater than twice the thickness of the honeycomb panel (3).

9. The sound insulation and vibration reduction partition for ship cabins containing an acoustic black hole according to claim 1, characterized in that: The thickness of the damping material layer (2) is not less than twice the thickness of the acoustic black hole thin plate layer (1).

10. The acoustic black hole containing ship cabin soundproofing and vibration damping panel of claim 1, wherein: The acoustic black hole thin plate layer (1), the damping material layer (2), and the honeycomb plate layer (3) are all the same in size and shape.

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