Quasi-zero stiffness type disc spring underwater sound insulation pressure-resistant structure based on stiffness regulation

Abstract

The application discloses a quasi-zero stiffness disc spring type underwater sound insulation pressure-resistant structure based on stiffness regulation, which comprises at least one annular disc spring type bearing unit, the annular disc spring type bearing unit comprises an inner pressure bearing ring and an outer pressure bearing ring, the central through hole of the inner pressure bearing ring is coaxial with the central through hole of the outer pressure bearing ring, the inner pressure bearing ring and the outer pressure bearing ring have a height difference in the axial direction, and the inner pressure bearing ring and the outer pressure bearing ring are connected into a whole through an elastic main body ring; the sound insulation pressure-resistant structure further comprises an upper pressure bearing plate arranged on the inner pressure bearing ring and a lower pressure bearing plate arranged on the outer pressure bearing ring. The application regulates the nonlinear mechanical response of the disc spring through parameters, so that the structure forms a low dynamic stiffness interval near the target water pressure or the target static load, and the static pressure resistance and the low-frequency sound insulation are considered; the continuous annular disc spring bearing unit is adopted as a core pressure bearing and sound insulation element, the pressure bearing path is continuous, the structure is compact, and the structure is suitable for installation and service in an underwater pressure environment.

Description

Technical Field

[0001] This invention relates to the field of underwater sound insulation, vibration reduction and noise reduction and pressure-bearing structure technology, and in particular to a quasi-zero stiffness disc spring underwater sound insulation and pressure-bearing structure based on stiffness control. Background Technology

[0002] Underwater equipment, hull structures, piping systems, and underwater load-bearing connectors are typically subjected to hydrostatic pressure, equipment loads, fluid pressure pulsations, and underwater acoustic excitation simultaneously during service. Traditional sound insulation or vibration isolation structures often employ rubber pads, elastic layers, metal springs, or composite damping layers. While these structures can reduce vibration transmission within a certain frequency range, they often present the following problems in underwater conditions: if the structure has high stiffness, its load-bearing and pressure resistance are good, but its dynamic vibration isolation and sound insulation effects are limited, especially in suppressing low-frequency acoustic vibration transmission; if the structure has low stiffness, its sound insulation and vibration isolation performance is improved, but it is prone to problems such as excessive pressure deformation, insufficient stability, or reduced reliability over long-term service.

[0003] Quasi-zero stiffness structures, through a combination of positive and negative stiffness or nonlinear stiffness effects, can achieve high static load-bearing capacity while maintaining low dynamic stiffness, thus offering advantages in low-frequency vibration and sound insulation. However, existing quasi-zero stiffness structures often employ combinations of various springs, linkages, magnetic elements, or complex negative stiffness mechanisms, resulting in complex structures and large volumes, which are unfavorable for sealing, installation, and long-term reliable service in underwater pressure environments. Therefore, there is a need for a compact structure with a continuous pressure path, easily designed parameters, and low dynamic stiffness sound insulation and pressure-resistant structure that can adapt to underwater pressure environments.

[0004] Disc spring-like structures are characterized by high axial load-bearing capacity, short deformation stroke, significant nonlinear mechanical characteristics, and flexible combination methods. By designing their geometric parameters, preload state, and combination methods, a low dynamic stiffness range can be formed near the target pressure displacement, thus balancing underwater pressure resistance and low-frequency sound insulation requirements. Summary of the Invention

[0005] To overcome the defects and shortcomings of the existing technology, the purpose of this invention is to provide a quasi-zero stiffness disc spring underwater sound insulation and pressure-resistant structure based on stiffness regulation. By utilizing the nonlinear deformation characteristics of continuous annular disc spring bearing units and combining methods such as superposition and pairing, a low dynamic stiffness working range is formed near a preset water pressure or preset bearing displacement, so that the structure can reduce the transmission of underwater sound waves, pressure pulsations and vibration energy while having good static pressure bearing performance.

[0006] The technical solution provided by this invention is as follows:

[0007] A quasi-zero stiffness disc spring-like underwater sound insulation and pressure-resistant structure based on stiffness control is disclosed. The structure includes at least one annular disc spring-like bearing unit, comprising an inner bearing ring and an outer bearing ring. The central through-holes of the inner and outer bearing rings are coaxial, and the inner and outer bearing rings have a height difference along the axial direction. The inner and outer bearing rings are connected as a whole by an elastic main body ring. The structure also includes an upper bearing plate on the inner bearing ring and a lower bearing plate on the outer bearing ring.

[0008] In this process, by adjusting the stiffness of the parameters of the ring-shaped disc spring bearing unit, the sound insulation and pressure-resistant structure forms a low dynamic stiffness working range near the preset water pressure or preset bearing displacement, thereby reducing the transmission of underwater sound waves, pressure pulsation and structural vibration while bearing static water pressure load.

[0009] The parameters include the outer diameter, inner diameter, ring width, thickness, material parameters and preload of the inner and outer bearing rings, as well as the cone height, cone angle and material parameters of the elastic main ring.

[0010] Preferably, the shape of the elastic main ring is selected from at least one of the conical surface and the arcuate surface of a disc spring.

[0011] Preferably, in the axial direction, multiple annular disc spring bearing units are combined in a manner of unidirectional stacking, reverse alignment, or a mixture of unidirectional stacking and reverse alignment; wherein, unidirectional stacking is used to improve the static pressure bearing capacity of the sound insulation and pressure-resistant structure, and reverse alignment is used to adjust the position, width, or compressive stability of the low dynamic stiffness working range.

[0012] Preferably, in the sound insulation and pressure-resistant structure, each annular disc spring bearing unit is continuously connected on the same plane perpendicular to the axis.

[0013] Preferably, the sound insulation and pressure-resistant structure further includes an upper pressure-bearing component and a lower pressure-bearing component, wherein the annular disc spring bearing unit is disposed between the upper pressure-bearing component and the lower pressure-bearing component.

[0014] This invention overcomes the shortcomings of existing underwater sound insulation structures in simultaneously achieving low-frequency sound insulation and pressure resistance, providing a quasi-zero stiffness disc spring-like underwater sound insulation and pressure-resistant structure based on stiffness control. The term "disc spring-like" in this invention does not refer to a standard disc spring, but rather to a ring-shaped elastic component similar to a disc spring in its structural shape and compressive deformation mechanism. Specifically, it is an elastic load-bearing unit with a central opening, a ring-shaped outer perimeter, and exhibiting significant nonlinear stiffness changes under axial compression. This component can be made of metal or composite materials. Its core lies in achieving pressure-bearing and stiffness control functions similar to a disc spring through the design of geometric parameters and assembly methods. The technical concept of this invention is to utilize the nonlinear compressive deformation characteristics of the continuous ring-shaped disc spring-like load-bearing unit, and by adjusting the outer diameter, inner diameter, thickness, cone height, cone angle, material parameters, and preload, to create a low dynamic stiffness working range near a preset water pressure or preset load displacement. The underlying technology lies in the fact that disc springs exhibit a nonlinear force-displacement response under axial compression, achieving lower tangential stiffness near the target working position. This reduces the transmission of underwater sound waves, pressure pulsations, and structural vibrations while maintaining static pressure resistance. The innovation of this invention lies in using a continuous, complete annular disc spring as the core sound insulation and pressure-resistant unit, and adjusting the equivalent stiffness and sound insulation frequency band through single-layer, double-layer reverse-pairing, or multi-layer combinations. Key technical aspects include disc spring geometric parameter design, pre-compression working point matching, quasi-zero stiffness range control, and synergistic optimization of underwater sound insulation and pressure resistance performance.

[0015] The beneficial effects of this invention after adopting the above technical solution are as follows:

[0016] (1) The present invention uses a continuous ring-shaped disc spring bearing unit as the core pressure-bearing and sound-insulating element. The pressure-bearing path is continuous and the structure is compact, making it suitable for installation and service in underwater pressure environments.

[0017] (2) The present invention controls the nonlinear mechanical response of the disc spring by adjusting parameters such as outer diameter, inner diameter, thickness, cone height, cone angle and preload, so that the structure forms a low dynamic stiffness range near the target water pressure or target static load, thereby taking into account both static pressure resistance and low frequency sound insulation.

[0018] (3) The present invention can improve the pressure bearing capacity by superimposing multiple continuous ring-shaped disc spring bearing units in the same direction, adjust the quasi-zero stiffness range and pressure stability by reverse coupling, and realize multi-level stiffness or wide frequency sound insulation design by hybrid combination. Attached Figure Description

[0019] Figure 1 This is a perspective structural diagram of one embodiment of the underwater sound insulation and pressure-resistant structure of the present invention;

[0020] Figure 2 yes Figure 1 A schematic diagram of the side cross-section of the underwater sound insulation and pressure-resistant structure shown.

[0021] Figure 3 yes Figure 1 A top view of the structure of a ring-shaped disc spring bearing unit;

[0022] Figure 4 This is a perspective structural diagram of a double-layer reverse-aligned structure in one embodiment of the underwater sound insulation and pressure-resistant structure of the present invention;

[0023] Figure 5 yes Figure 4 A schematic diagram of the side cross-section of the double-layered reverse-jointing structure shown.

[0024] Figure 6 This is a schematic diagram of the force-displacement curve of the structure of the present invention forming a quasi-zero stiffness range near the pre-compression state;

[0025] Figure 7 This is a schematic diagram of the sound transmission loss curve when the structure of the present invention is used for underwater sound insulation;

[0026] Figure 8 This is a schematic diagram of the ideal sound transmission loss curves under different hydrostatic pressures when the single-layer structure of the continuous annular disc spring bearing unit of the present invention is used for underwater sound insulation.

[0027] Figure 9 This is a schematic diagram of stiffness-displacement curves for different combinations of the structure of this invention. Detailed Implementation

[0028] The technical solution of the present invention will be further described in detail below with reference to specific embodiments, but this does not constitute any limitation on the present invention.

[0029] This invention discloses a quasi-zero stiffness disc spring-like underwater sound insulation and pressure-resistant structure based on stiffness control, such as... Figures 1-3As shown, the sound insulation and pressure-resistant structure includes at least one annular disc spring-like bearing unit 1. The annular disc spring-like bearing unit 1 includes an inner pressure-bearing ring 11 and an outer pressure-bearing ring 12. The central through hole of the inner pressure-bearing ring 11 and the central through hole of the outer pressure-bearing ring 12 are coaxial. The inner pressure-bearing ring 11 and the outer pressure-bearing ring 12 have a height difference in the axial direction, and the inner pressure-bearing ring 11 and the outer pressure-bearing ring 12 are connected as a whole by an elastic main body ring 13. The sound insulation and pressure-resistant structure also includes an upper pressure plate 14 disposed on the inner pressure-bearing ring 11 and a lower pressure plate 15 disposed on the outer pressure-bearing ring 12. Specifically, by adjusting the stiffness of the parameters of the annular disc spring bearing unit 1, the sound insulation and pressure-resistant structure forms a low dynamic stiffness working range near the preset water pressure or preset bearing displacement, thereby reducing the transmission of underwater sound waves, pressure pulsations and structural vibrations while bearing static water pressure loads. The parameters include the outer diameter, inner diameter, ring width, thickness, material parameters and preload of the inner bearing ring 11 and the outer bearing ring 12, as well as the cone height, cone angle and material parameters of the elastic main body ring 13.

[0030] In a further preferred embodiment, the shape of the elastic main body ring 13 is selected from at least one of a conical surface or an arcuate surface similar to a disc spring.

[0031] In a further preferred embodiment, in the axial direction, a plurality of the annular disc spring bearing units 1 are combined in a manner of unidirectional stacking, reverse alignment, or a mixture of unidirectional stacking and reverse alignment; wherein, the unidirectional stacking is used to improve the static pressure bearing capacity of the sound insulation and pressure-resistant structure, and the reverse alignment is used to adjust the position, width, or compressive stability of the low dynamic stiffness working range. Specifically, as shown... Figures 4-5 As shown in the embodiment of the invention, a method is provided where two annular disc spring-like bearing units 1 are opposed to each other in a reverse manner. Compared with a single-layer structure, the double-layer reverse-opposed structure can form a more stable pressure-bearing path during axial compression, and adjust the overall equivalent stiffness through the nonlinear deformation coupling of the two disc spring-like units. By changing the opposition method, preload, and material parameters, the structure can form a low dynamic stiffness working range near a preset water pressure or preset bearing displacement, thereby reducing acoustic vibration energy transmission while maintaining pressure bearing capacity.

[0032] Furthermore, in the sound insulation and pressure-resistant structure, each annular disc spring bearing unit 1 is continuously connected on the same plane perpendicular to the axis, thereby forming a pressure-resistant structure with a larger area.

[0033] like Figure 6 The figure shows the force-displacement curves under different structural forms or material parameters. COMSOL Multiphysics 6.3 simulation software was used to simulate the compressive strength of different materials in a single-layer sound-insulating and pressure-resistant structure, and to demonstrate the ability to control the stiffness of a double-layer reverse-pairing structure. Figure 6It can be seen that the bearing capacity of a single-layer structure increases significantly with the increase of the material's elastic modulus, indicating that the structure's compressive capacity and equivalent stiffness can be adjusted through material parameters. The double-layer, reverse-coupled structure exhibits piecewise nonlinear bearing characteristics over a large compressive displacement range. Its curve has a lower slope in local displacement intervals, indicating that this structure can form a low dynamic stiffness range through combination. This low dynamic stiffness range corresponds to the structure's target preload or target bearing position, which is beneficial for reducing the transmission of underwater acoustic waves, pressure pulsations, and structural vibrations.

[0034] like Figure 7 The figure shows the underwater sound insulation curves for single-layer and double-layer reverse-aligned structures. A model was built using COMSOL Multiphysics 6.3 simulation software, and the sound transmission loss was calculated using TL = 10log(Ei / Et). Figure 7 It is evident that both single-layer and double-layer structures exhibit significant peak sound transmission loss within specific frequency bands, indicating that the disc spring-like single-layer structure can improve underwater sound insulation performance through stiffness adjustment and nonlinear load-bearing characteristics. Furthermore, the peak sound insulation frequency and curve shape of the double-layer reverse-paired structure change compared to the single-layer structure, demonstrating that the sound insulation frequency band and effect can be adjusted through reverse-pairing combinations. Therefore, based on the actual underwater noise frequency range, single-layer structures, double-layer reverse-paired structures, or multiple layer combinations can be selected to achieve sound insulation design within the target frequency band.

[0035] Depend on Figure 8 As shown, a boundary load was applied to the pressure-bearing surface of the single-layer structure in COMSOL Multiphysics 6.3 to simulate its stress environment during actual operation. Within an external water pressure range of 0 MPa to 3 MPa, the quasi-zero stiffness disc spring-type underwater sound-insulating and pressure-resistant structure exhibited a significant peak sound transmission loss around approximately 2200 Hz, indicating that the structure has good underwater sound insulation performance in the corresponding frequency band. With increasing external water pressure, the sound transmission loss curve shifted upwards overall, with the peak sound transmission loss increasing from approximately 45 dB to approximately 60 dB, and the sound transmission loss also increased in both the low-to-mid frequency and mid-to-high frequency ranges. These results demonstrate that the structure in this embodiment can maintain stable sound insulation performance under different hydrostatic pressures, and within a certain pressure range, increasing external water pressure is beneficial for improving the structure's sound transmission loss.

[0036] like Figure 9As shown, in COMSOL Multiphysics 6.3, a specified displacement is applied to the upper pressure surface of the structure, while a fixed constraint is applied to the lower pressure surface. The preload displacement of the structure can be determined based on the target water depth, hydrostatic pressure, and equipment load. For the single-layer structure, the stiffness gradually decreases with increasing compressive displacement, entering a low-stiffness range around 3 mm, after which the stiffness rapidly increases. For the double-layer reverse-coupled structure, the low-stiffness range shifts to a larger displacement range, exhibiting lower equivalent stiffness in the range of approximately 4 mm to 7 mm, locally approaching zero stiffness. These results demonstrate that by adjusting material parameters and the double-layer coupling method, the position and range of the quasi-zero stiffness range can be adjusted, allowing the structure to possess both low dynamic stiffness sound insulation and pressure-bearing capacity near the target water pressure or preload displacement.

[0037] In a further preferred embodiment, the sound-insulating and pressure-resistant structure further includes an upper pressure-bearing member 21 and a lower pressure-bearing member 22, wherein the annular disc spring-like bearing unit 1 is disposed between the upper and lower pressure-bearing members. In actual installation, a continuous annular disc spring-like bearing unit 1 or a double-layer reverse-aligned structure can be disposed between the upper and lower pressure-bearing members. The upper and lower pressure-bearing members are used to connect underwater equipment, hull panels, pipeline supports, or sound-insulating bases, and to transfer external hydrostatic pressure and equipment load to the disc spring-like bearing unit.

[0038] The design process of this invention may include the following steps: First, determine the required static load-bearing capacity and target low dynamic stiffness range of the structure based on the target water depth, hydrostatic pressure, equipment weight, and target sound insulation frequency band; second, determine the outer diameter, inner diameter, thickness, cone height, cone angle, and material parameters of the continuous annular disc spring bearing unit 1; third, obtain the bearing curve of the structure through finite element simulation or force-displacement testing, and determine the pre-loading working position based on the low slope range of the curve; finally, select a single-layer structure, a double-layer reverse-paired structure, or a multi-layer combined structure according to the sound insulation requirements, and verify the sound insulation effect through underwater sound transmission loss testing or vibration transmissibility testing.

[0039] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A quasi-zero stiffness disc spring-like underwater sound insulation and pressure-resistant structure based on stiffness control, characterized in that, The sound insulation and pressure-resistant structure includes at least one annular disc spring-like bearing unit. The annular disc spring-like bearing unit includes an inner pressure-bearing ring and an outer pressure-bearing ring. The central through-hole of the inner pressure-bearing ring and the central through-hole of the outer pressure-bearing ring are coaxial. There is a height difference between the inner and outer pressure-bearing rings in the axial direction, and the inner and outer pressure-bearing rings are connected as a whole by an elastic main body ring. The sound insulation and pressure-resistant structure also includes an upper pressure-bearing plate disposed on the inner pressure-bearing ring and a lower pressure-bearing plate disposed on the outer pressure-bearing ring. In this process, by adjusting the stiffness of the parameters of the ring-shaped disc spring bearing unit, the sound insulation and pressure-resistant structure forms a low dynamic stiffness working range near the preset water pressure or preset bearing displacement, thereby reducing the transmission of underwater sound waves, pressure pulsation and structural vibration while bearing static water pressure load. The parameters include the outer diameter, inner diameter, ring width, thickness, material parameters and preload of the inner and outer bearing rings, as well as the cone height, cone angle and material parameters of the elastic main ring.

2. The sound-insulating and pressure-resistant structure as described in claim 1, characterized in that, The shape of the elastic main ring is selected from at least one of the conical surface and arc surface of a disc spring.

3. The sound-insulating and pressure-resistant structure as described in claim 1, characterized in that, In the axial direction, multiple annular disc spring bearing units are combined in a manner of unidirectional stacking, reverse alignment, or a mixture of unidirectional stacking and reverse alignment; wherein, unidirectional stacking is used to improve the static pressure bearing capacity of the sound insulation and pressure-resistant structure, and reverse alignment is used to adjust the position, width, or compressive stability of the low dynamic stiffness working range.

4. The sound-insulating and pressure-resistant structure as described in claim 3, characterized in that, In the sound insulation and pressure-resistant structure, each annular disc spring bearing unit is continuously connected on the same plane perpendicular to the axis.

5. The sound-insulating and pressure-resistant structure as described in claim 1, characterized in that, The sound insulation and pressure-resistant structure also includes an upper pressure-bearing component and a lower pressure-bearing component, wherein the annular disc spring bearing unit is disposed between the upper pressure-bearing component and the lower pressure-bearing component.

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