Compact superstructure for pipeline broadband vibration suppression and design method thereof

Abstract

The invention belongs to the technical field of vibration reduction, and discloses a pipeline broadband vibration suppression compact superstructure and a design method thereof.The compact superstructure is used for vibration reduction of a pipeline body and comprises superstructure unit cells, the superstructure unit cells are installed on the outer wall of the pipeline body and composed of 12 mass units and 30 connecting rods, and the mass units are connected with the connecting rods. Each mass unit is connected with the five connecting rods to form an icosahedron structure, and each mass unit comprises a mass ball and an external wrapping layer wrapping the outer wall of the mass ball. The multi-direction and multi-frequency local resonance device has the beneficial effects that through the space spring design of the superstructure unit cells and the space array distribution of the vibrators, multi-direction and multi-frequency local resonance is achieved, then a plurality of vibration reduction belts can be generated in multiple directions of the pipeline, and the broadband vibration reduction design of the pipeline under the limited space condition is achieved.

Description

Technical Field

[0001] The present invention relates to the field of vibration reduction technology, and in particular to a compact superstructure for suppressing broadband vibration of a pipeline and a design method thereof. Background Art

[0002] Submarine piping systems, as the core infrastructure of deep-sea equipment, are responsible for transporting fluids such as fuel, lubricating oil, and cooling water. While ensuring efficient fluid transport, these systems are inevitably subject to multiple excitations, such as fluid pulsation and mechanical vibration, triggering three-dimensional, multi-directional vibration responses with a wide frequency band ranging from tens to hundreds of hertz. This vibration energy propagates through the piping structure as elastic waves, ultimately converting into underwater radiated noise. This becomes one of the primary sources of acoustic emissions during a submarine's silent cruise mode, directly threatening its stealth performance. However, due to space constraints within the submarine, piping must be densely integrated with electronic equipment, bulkhead structures, and pressure hulls, resulting in a highly dense arrangement of transverse and longitudinal piping. This confined installation environment makes traditional full-circumferential three-dimensional vibration damping devices difficult to implement, necessitating the development of compact design technologies for multi-directional, broadband vibration suppression within limited space constraints.

[0003] Traditional multi-directional vibration reduction technology for pipelines relies primarily on a fully circumferentially wrapped spring-mass system, achieving a single-frequency bandgap through localized resonance. This technology suffers from two significant technical bottlenecks: First, it can only produce a single damping band, typically with a bandwidth of only tens of Hz, preventing full coverage and broadband vibration suppression. Second, the full-circumferential design requires extensive installation space, fundamentally conflicting with the densely packed piping within submarines. Multi-frequency localized resonance superstructures are an effective means of achieving broadband vibration reduction under small amplitude conditions. However, their traditional design requires multiple independent spring-oscillator systems, which not only takes up a significant amount of installation space but also makes it difficult to achieve coordinated suppression of multi-directional vibrations. If the multi-frequency oscillators and springs can be integrated into a spatial design and optimized to create multi-directional, multi-frequency localized resonance bandgap, it is possible to achieve multi-directional, broadband vibration suppression for pipelines through a unidirectional superstructure design, thereby overcoming spatial constraints. This has important engineering implications for vibration and noise reduction, as well as acoustic stealth protection, for pipeline systems in submarines and other equipment.

[0004] Therefore, it is necessary to provide a compact superstructure for broadband vibration suppression of pipelines and its design method, which can be used for multi-directional broadband vibration reduction of complex piping systems in deep-sea equipment such as submarines and unmanned underwater vehicles. Summary of the Invention

[0005] The present invention discloses a compact superstructure for suppressing broadband vibration of a pipeline and a design method thereof, which can effectively solve the technical problems involved in the background technology.

[0006] To achieve the above object, the technical solution of the present invention is: A compact superstructure for suppressing broadband vibration of a pipeline is used for vibration reduction of the pipeline body. The compact superstructure includes a superstructure unit cell, which is installed on the outer wall of the pipeline body. The superstructure unit cell is composed of 12 mass units and 30 connecting rods. Each mass unit is connected to 5 connecting rods to form an icosahedron structure. The mass unit includes a mass sphere and an external wrapping layer covering the outer wall of the mass sphere.

[0007] This invention aims to provide a compact superstructure for multi-directional, broadband vibration reduction in pipelines. This superstructure supports unidirectional layout, arbitrary circumferential design, and flexible installation. It achieves 360° multi-directional vibration absorption and broadband (0-1000Hz) vibration suppression, effectively improving space utilization and meeting installation requirements in a variety of working conditions. The invention also proposes a corresponding design method to address the difficulty of traditional vibration-absorbing structures in achieving multi-directional, broadband vibration reduction in pipelines within confined engineering spaces.

[0008] As a preferred improvement of the present invention: the mass ball is made of metal, the outer wrapping layer is made of viscoelastic material, and the connecting rod is made of viscoelastic material.

[0009] As a preferred improvement of the present invention: the number of the superstructure unit cells is multiple.

[0010] As a preferred improvement of the present invention: a plurality of the superstructure unit cells are arranged at equal intervals along the length direction of the pipe body, and the plurality of the superstructure unit cells are located in the same straight line or are evenly or unevenly distributed along the circumference of the pipe body.

[0011] As a preferred improvement of the present invention: the compact superstructure also includes a mounting base and an upper boss of the base, the mounting base is fixed to the pipe body by a clamp, the upper boss of the base is installed on the mounting base, the upper boss of the base is provided with a rod-shaped slot and a hemispherical slot, and the superstructure unit cell is fixed to the rod-shaped slot and the hemispherical slot by an adhesive.

[0012] As a preferred improvement of the present invention: the superstructure unit cell has a centrally symmetrical structure, and the superstructure unit cell has two parallel regular pentagonal planes, and the two parallel regular pentagonal planes form an angle of 36° with each other in the parallel planes.

[0013] A design method for a compact superstructure for broadband vibration suppression of pipelines includes the following steps: S1. Perform vibration testing on the pipeline body without any additional structure to obtain the pipeline's own multi-directional natural resonance frequency and amplitude X1; S2. Preliminarily set the geometric parameters of the superstructure unit cell according to the resonance frequency of the pipeline body; S3. Establish a finite element model of the superstructure unit cell; S4. Apply modal analysis to simulate the vibration modes at different installation angles and obtain the resonant frequencies of the superstructure unit cell in each direction; S5. Determine whether the superstructure unit cell resonant frequency covers the pipe body resonant frequency. The judgment criteria are: compare the superstructure unit cell resonant frequency with the pipe body resonant frequency. If the superstructure unit cell resonant frequency completely covers the pipe body resonant frequency band to be suppressed, proceed to the next step. If not, return to step S2, adjust the superstructure unit cell parameters, and repeat the modeling and analysis until the coverage requirement is met. S6. Arrange and install the superstructure unit cells according to the actual installation space of the pipeline body; S7. Establish a finite element model of the superstructure pipeline; S8. Calculate the insertion loss IL of the superstructure pipe. , where X2 is the amplitude of the measuring point of the superstructure pipe; S9, verify whether the simulation results are consistent with the experimental test results, compare the insertion loss results of the finite element simulation with the experimental test results, if the error is within the allowable range, proceed to the next step; if the error is too large, return to step S7, correct the model parameters, and recalculate and verify; S10, analyzing whether the vibration reduction performance of the superstructure pipeline meets the requirements, and determining whether the vibration reduction performance of the superstructure pipeline meets the standards. If so, proceed to the next step; if not, return to step S2 or S7, and repeat the subsequent process until the requirements are met; S11. Output superstructure design parameters and layout results.

[0014] As a preferred improvement of the present invention: in step S1, a wide-band white noise excitation is applied to the pipeline body using an excitation device, a measuring point is selected at the end of the pipeline body, and pipeline vibration response data is collected using an acceleration sensor; In step S2, the geometric parameters include but are not limited to the size of the superstructure unit cell, the length of the connecting rod, the material density of the mass ball, and the elastic modulus of the connecting rod; In step S3, finite element analysis software is used to perform three-dimensional modeling of the superstructure unit cell, define material properties of each component, divide the grid, and set boundary conditions. The finite element analysis software includes but is not limited to ANSYS and COMSOL; In step S6, the number of additional superstructure units is determined according to the additional quality restrictions of the project, and the installation position and arrangement of the superstructure units are determined in combination with the shape of the pipeline body and the installation environment; In step S7, based on the arranged superstructure pipe, an overall finite element model including the pipe body and the superstructure unit cell is established, and the contact settings of the connection interface between the pipe body and the superstructure unit cell are refined. The contact settings include but are not limited to binding contact and friction coefficient.

[0015] As a preferred improvement of the present invention: in step S9, the error is no more than 10%.

[0016] As a preferred improvement of the present invention: in step S10, the compliance standard is based on the insertion loss of actual experimental test being no less than 10 dB.

[0017] The beneficial effects of the present invention are as follows: Through the spatial spring design of the superstructure unit cell and the spatial array distribution of the oscillators, multi-directional and multi-frequency local resonance is achieved, which can generate multiple vibration reduction belts in multiple directions of the pipeline, realizing the broadband vibration reduction design of the pipeline under limited space conditions. Multidirectional vibration reduction can be achieved through the unidirectional arrangement of superstructures, realizing a compact design for multidirectional, broadband vibration reduction of pipelines under limited space conditions. Superstructure cells can be arbitrarily arranged around the circumference of the pipeline based on the installation space under actual working conditions. This not only does not reduce the pipeline's vibration reduction performance, but also potentially generates circumferential bandgap coupling, further widening the vibration reduction band. The physical mechanism of circumferential bandgap coupling here refers to the fact that superstructure cells installed at different angles have a slight offset in the bandgap frequency band within the same plane. These offset bandgaps, through the interference and superposition effects of vibration waves, form a wider comprehensive vibration reduction frequency band, breaking through the bandwidth limitations of traditional unidirectional uniform arrays. The superstructure unit cell is adjustable. By adjusting parameters such as the unit cell spacing, the thickness or length of the rod, the vibration reduction performance can be optimized, band gap coupling can be generated, the vibration reduction frequency band can be widened, and new resonance peaks can be suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive work, among which: Figure 1 It is a schematic diagram of the superstructure pipeline structure arranged in one direction in the present invention; Figure 2 It is a structural design diagram of the superstructure unit cell in the present invention; Figure 3 It is a schematic diagram of the mass unit in the present invention; Figure 4 It is the mounting base of the superstructure unit cell of the present invention on the pipeline; Figure 5 Schematic diagram of a unidirectionally arranged superstructure pipe with different installation angles in the present invention; Figure 6 This is a schematic diagram of a pipeline with circumferentially equiangular spiral arrangement of superstructure unit cells in the present invention; Figure 7 is a flow chart of the design method of the superstructure pipeline in the present invention; Figure 8 This is a comparison chart of the insertion loss-excitation frequency curve at the output point of the superstructure pipeline between simulation and experimental results; Figure 9 is the insertion loss-excitation frequency curve of the output point of the pipeline at different installation angles of the unit cell; Figure 10 It is the insertion loss-excitation frequency curve of the pipeline output point position of the unidirectional arrangement and spiral arrangement superstructure unit cell.

[0019] In the figure: 10-pipe body, 210-upper boss of the base, 211-rod-shaped slot, 212-hemispherical slot, 22-mounting base, 30-superstructure unit cell, 31-connecting rod, 320-mass unit, 321-mass ball, 322-external wrapping layer, 40-clamp. DETAILED DESCRIPTION

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0022] In addition, the terms "first," "second," and so on, used in this disclosure are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referenced. Thus, a feature specified as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of this disclosure, "plurality" means at least two, such as two or three, unless otherwise specifically defined.

[0023] In the present invention, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will be able to understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0024] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in this field can implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0025] See also Figure 1 As shown, the present invention provides a compact superstructure for broadband vibration suppression of pipelines, comprising a superstructure unit cell 30, a mounting base 22, and a boss 210 on the base. The superstructure unit cells 30 are arranged in an array with equal spacing on the pipeline body 10. Figure 2 The superstructure unit cell 30 is composed of 12 mass units 320 of equal volume and mass and 30 connecting rods 31 of equal length, creating a centrosymmetric structure that ensures balanced and equivalent multi-directional vibration suppression. The three connecting rods 31 are connected by the nodes of the mass units 320, forming an equilateral triangle. Each node of the mass unit 320 is connected to five adjacent mass units 320 by five connecting rods 31, and the five adjacent mass units 320 are arranged in a regular pentagon (an icosahedron structure). Compared to designs with four or fewer connecting rods, this five-rod design significantly increases the number of modes in the overall superstructure unit cell (verified by modal analysis). The modal frequency distribution range extends from tens to several thousand Hz, effectively covering multiple resonance peaks within the target frequency band of the pipeline and producing a wide-band vibration reduction effect. However, when using a structure with six or more connecting rods, while the number of modes increases, the unit cell volume increases significantly (based on finite element parametric modeling data), significantly increasing the system space requirement and conflicting with the requirements of a compact equipment layout. Therefore, the five-bar connection structure achieves the optimal balance between modal coverage and space occupancy, and the regular polyhedron can produce the closest possible vibration absorption effect in all directions.

[0026] The plane distances (h1 and h3) between each mass unit 320 and the nodes of the five adjacent mass units 320 can be uniquely determined by the length l of the connecting rod 31 and the distance r from the midpoint of the regular pentagon to the mass unit. The superstructure unit cell 30 has two parallel regular pentagonal planes, and the distance h2 between them can also be uniquely determined by the length l of the connecting rod 31 and the distance r from the midpoint of the regular pentagon to the mass unit 320. . The two parallel regular pentagonal planes form an angle of 36° with each other in the parallel planes. The single mass unit 320 is composed of a metal mass ball 321 and an outer wrapping layer 322, which provides a spatial spring and an oscillator to produce a multi-directional resonance effect. The metal mass ball 321 is made of a high-density material (density ≥ 5g / cm³), and the optional range is steel, lead, etc. The outer wrapping layer 322 uses a high-damping material (damping ratio ζ ≥ 0.1), provides a spatial spring and damping, and the optional range is: rubber, plastic, etc. The thickness of the outer wrapping layer 322 should be less than 1 / 10 of the metal mass ball 321. The connecting rod 31 is made of viscoelastic material, provides damping and serves as a spring element, forms a local resonance system with the oscillator, and is made of the same material as the outer wrapping layer 322. The length of the connecting rod 31 must exceed the outer wrapping layer 322 of the single mass unit 320, and the cross-section is circular, and the cross-sectional diameter cannot exceed that of the single mass unit 320. The mounting base 22 has an arc-shaped mating surface that matches the surface of the pipe body 10, arranged symmetrically from top to bottom. Both sides are fastened to the pipe by clamps 40. The superstructure unit cells 30 can rotate 0°-360° around the pipe circumference, allowing for installation at appropriate angles to accommodate the varying installation spaces available at different locations on the pipe. Where installation space permits, the superstructure unit cells can be arranged in a unidirectional array for multi-directional vibration reduction, or in a spiral arrangement along the axial direction to form a three-dimensional array, stimulating circumferential bandgap coupling (bandgap coupling is not necessarily required, depending on the actual installation space) and broadening the vibration reduction frequency band. Circumferential bandgap coupling refers to the fact that the bandgap frequencies of superstructure unit cells installed at different angles within the same plane deviate slightly, and the interaction between these bandgaps results in bandgap widening.

[0027] The superstructure unit cell 30 is embedded in the rod-shaped slot 211 and the hemispherical slot 212. After positioning, it is fixed with a high-strength adhesive (shear strength ≥ 15MPa, tensile strength ≥ 20MPa), and then installed on the upper boss 210 of the base on the mounting base 22. The rod-shaped slot 211 is consistent in size with the connecting rod 31. The hemispherical slot 212 is consistent in size with the outer wrapping layer 322. The mounting base 22 is semicircular in shape, which can fit the surface of the pipe and is installed symmetrically up and down and pre-fixed on the surface of the pipe. The base and the pipe are fastened together on both sides by means of clamps 40 to ensure a stable structure. The preload force F of the clamp material is in the range of 500-800N. The material of the mounting base 22 and the upper boss 210 of the base should be a lightweight and high-rigidity material, and the optional range is: nylon material, carbon fiber reinforced composite material, aluminum alloy, etc. The superstructure unit cell 30 can be installed unidirectionally at a certain angle α (0≤α≤360°) (such as Figure 5 ), or it can be installed at different angles according to the installation space under actual engineering conditions (such as Figure 6 ), unidirectional installation means that each superstructure unit cell 30 is in a vertical plane.

[0028] The design method of a compact superstructure with broadband vibration suppression for multi-directional piping has the following basic steps: Step 1: Perform a vibration test on the pipe body 10 (bare pipe) without any additional structure. Use a vibration excitation device to apply broadband white noise excitation (e.g., 0-1000 Hz) to the pipe. Use accelerometers to collect multi-directional vibration response data. Obtain the inherent resonant frequencies of the pipe at different circumferential locations. This provides a frequency matching target for subsequent superstructure unit cell design and clarifies the vibration frequency range to be suppressed.

[0029] Step 2: Based on the resonant frequency of the light tube, preliminarily set the geometric parameters of the superstructure unit cell 30 (including the overall size of the superstructure unit cell 30, the diameter of the mass unit 320, the length and cross-sectional diameter of the connecting rod 31, etc.), and the material parameters (including the material density of the metal mass ball 321, the elastic modulus and damping ratio of the elastic connecting rod 31 and the outer wrapping layer 322, etc.). Combined with engineering experience, determine the initial structural form of the unit cell with a centrosymmetric five-way connecting rod layout to ensure that the unit cell has multi-directional vibration absorption capabilities.

[0030] Step 3: Create a finite element model of the superstructure unit cell. Use professional finite element analysis software (such as ANSYS or COMSOL) to perform a 3D model of the superstructure unit cell, define the material properties of each component (density, elastic modulus, damping parameters), create a mesh (using adaptive mesh refinement to improve accuracy), and set boundary conditions (such as free vibration boundaries).

[0031] Step 4: Resonant modal analysis of the superstructure unit cell 30 at different installation angles. Modal analysis is performed on the superstructure unit cell to simulate the vibration modes at different installation angles (from 0° to 360°). The resonant frequencies of the unit cell in each direction are obtained, and the multidirectional vibration characteristics of the unit cell are clarified to ensure that its resonant frequency covers the natural resonant frequency of the pipeline.

[0032] Step 5: Determine whether the unit cell resonant frequency covers the pipe resonant frequency. Judgment criteria: Compare the resonant frequency of the superstructure unit cell 30 with the resonant frequency of the light pipe. If the unit cell resonant frequency completely covers the resonant frequency band of the pipe to be suppressed, proceed to the next step. If not, return to the "Initial Parameter Design of Superstructure Unit Cell 30" step and adjust the unit cell parameters (for example, optimizing the mass of mass ball 321 and the thickness of connecting rod 31). Repeat modeling and analysis until the coverage requirement is met.

[0033] Step 6: Arrange and install superstructure cells 30 based on the actual installation space of the pipeline. Considering the shape of the pipeline body 10 and the installation environment (e.g., pipeline orientation and spatial size restrictions), determine the installation location, quantity, and arrangement of superstructure cells 30 (e.g., periodic unidirectional array, non-unidirectional arrangement).

[0034] Step 7: Create a finite element model of the superstructure pipe. Based on the arranged superstructure pipe, create a complete finite element model consisting of the pipe body 10, superstructure unit cells 30, mounting base 22, and upper boss 210. Refine the contact settings (e.g., binding contact and friction coefficient) at the interface between the pipe body 10 and superstructure unit cells 30 to ensure that the model faithfully reflects the actual structural dynamics.

[0035] Step 8: Calculate the insertion loss of the superstructure duct , where X1 is the amplitude at the measured point on the light pipe, and X2 is the amplitude of the superstructure pipe. Using a finite element model to simulate the pipeline vibration transmission process, the insertion loss IL of the superstructure pipe within the target frequency range is calculated. This allows the vibration reduction effect of the superstructure pipe to be quantified and its ability to suppress pipeline vibration to be evaluated.

[0036] Step 9: Verify the consistency between the simulation results and the experimental test results. Compare the insertion loss results of the finite element simulation with the experimental test results. If the error is within the allowable range (e.g., ≤10%), proceed to the next step. If the error is too large, return to the "Establishing the Finite Element Model of the Superstructure Pipe" step, modify the model parameters (such as material properties and contact settings), and recalculate and verify.

[0037] Step 10: Analyze whether the superstructure piping's vibration reduction performance meets requirements. Based on engineering vibration reduction indicators (e.g., insertion loss IL ≥ 10dB in the target frequency band), determine whether the superstructure piping's vibration reduction performance meets the standards. If so, output the design results. If not, return to adjust the superstructure unit cell parameters or layout, and repeat the subsequent process until the requirements are met.

[0038] Step 11: Output superstructure design parameters and layout results. Organize and output the geometric parameters of the superstructure unit cell 30 (such as mass unit dimensions and connecting rod 31 dimensions), material parameters (materials of various components), and installation layout (unit cell location, quantity, and installation angle) to form a complete superstructure piping design file. Example 1

[0039] This example gives the calculation and experimental results of the vibration reduction performance of a specific superstructure pipeline, such as Figure 8As shown in the figure, the pipe body 10 is made of non-plasticized polyvinyl chloride (with a density of 1350 kg / m³, a Young's modulus of 4.8e9 Pa, and a Poisson's ratio of 0.319). The pipe body 10 is 1 meter long, with an inner radius of 50 mm and an outer radius of 55 mm. The spacing between adjacent superstructure cells 30 is 200 mm, and five superstructure cells are installed. The superstructure cells 30 are arranged in the same plane as the vibration measurement point, i.e., at an angle of 0°. Based on the above superstructure design method, the metal mass ball 321 is made of stainless steel (density 7850 kg / m³, Young's modulus 2.1e11 Pa, Poisson's ratio 0.3), the mounting base 22 is made of photosensitive resin (density 1160 kg / m³, Young's modulus 2.48e9 Pa, Poisson's ratio 0.41), and the connecting rod 31 and outer covering layer 322 are made of thermoplastic polyurethane elastomer rubber (density 1200 kg / m³, Young's modulus 8e9 Pa, Poisson's ratio 0.4). The mass ball 321 has a diameter of 9 mm, and the connecting rod 31 has a cross-sectional diameter of 3.6 mm and a length of 22 mm. Figure 8 The insertion loss-frequency curves obtained from the experiments and simulations show a high degree of consistency in their trends, with minimal deviations in amplitude and bandgap frequency within the 148Hz-180Hz range. This verifies the accuracy of the design and calculations. The experimental and simulation results show that the superstructure tube exhibits multi-bandgap characteristics within the frequency ranges of 21-38Hz and 160-221Hz, achieving a reduction of up to 18dB. These results demonstrate that the superstructure tube effectively suppresses the propagation of vibration energy in the low-frequency range, verifying the practical effectiveness of its bandgap characteristics. Example 2

[0040] This example provides a specific calculation result of the vibration reduction performance of the superstructure unit cell 30 under different circumferential arrangement angles of the pipe body 10, as shown in FIG. Figure 9As shown, the pipe body 10 is made of vinyl chloride (density 1350 kg / m³, Young's modulus 3e9 Pa, Poisson's ratio 0.319), is 1 meter long, has an inner radius of 50 mm, and an outer radius of 55 mm. Adjacent cells are spaced 200 mm apart, and five superstructure cells 30 are installed, arranged at 0°, 45°, and 90° angles. Based on the above superstructure design method, the metal mass ball 321 is made of stainless steel (density 7850 kg / m³, Young's modulus 2.1e11 Pa, Poisson's ratio 0.3), the mounting base 22 is made of photosensitive resin (density 1160 kg / m³, Young's modulus 2.48e9 Pa, Poisson's ratio 0.41), and the connecting rod 31 and outer covering layer 322 are made of thermoplastic polyurethane elastomer rubber (density 1200 kg / m³, Young's modulus 8e9 Pa, Poisson's ratio 0.4). The mass ball 321 has a diameter of 9 mm, and the connecting rod 31 has a cross-sectional diameter of 3.6 mm and a length of 22 mm.

[0041] like Figure 9 As shown in the figure, within the frequency range of 100-200Hz, the average insertion loss of the superstructure pipe structure arranged at different angles exceeds 20dB. Among them, the superstructure pipe arranged at 90° along the excitation direction achieves the lowest frequency range and the widest vibration suppression band, with the highest insertion loss reaching 50dB; the superstructure pipe vibration suppression band arranged at 45° has a maximum insertion loss of 40dB; the superstructure pipe arranged at 0° along the excitation direction has a maximum insertion loss of 23dB. In all three cases, two vibration reduction band gaps are generated in the 0-300Hz range, showing a broadband vibration reduction effect. Example 3

[0042] This example gives the calculation results of the pipeline vibration reduction performance under the conditions of a specific unidirectional superstructure and a spiral superstructure, such as Figure 10As shown in the figure, the pipe body is made of vinyl chloride (density 1350 kg / m³, Young's modulus 3e9 Pa, Poisson's ratio 0.319), 1 meter long, with an inner radius of 50 mm and an outer radius of 55 mm. Adjacent unit cells are spaced 160 mm apart, and six superstructure units are installed. The unidirectional superstructures are all arranged in a 0° orientation. A spiral superstructure arrangement involves rotating the angle between adjacent superstructure units by 60°, either clockwise or counterclockwise. Based on the above superstructure design method, the metal mass ball 321 is made of stainless steel (density 7850 kg / m³, Young's modulus 2.1e11 Pa, Poisson's ratio 0.3), the base 22 is made of photosensitive resin (density 1160 kg / m³, Young's modulus 2.48e9 Pa, Poisson's ratio 0.41), and the connecting rod 31 and outer covering layer 322 are made of thermoplastic polyurethane elastomer rubber (density 1200 kg / m³, Young's modulus 8e9 Pa, Poisson's ratio 0.4). The mass ball 321 has a diameter of 9 mm, and the connecting rod 31 has a cross-sectional diameter of 3.6 mm and a length of 22 mm.

[0043] like Figure 10 As shown, the superstructure unit cells 30 are arranged in a spiral pattern, creating multiple vibration damping zones within the low-frequency range of 0-300 Hz, effectively controlling the low-frequency vibrations of the pipeline. Compared to unidirectional superstructure pipelines, the spiral arrangement of the pipeline creates circumferential bandgap coupling, further widening the vibration damping zones and reducing the amplitude of the additional spillover vibrations. This allows for wider frequency vibration control and more significant vibration suppression.

[0044] The spatial spring design of the superstructure unit cells and the spatial array distribution of the oscillators achieve multi-directional and multi-frequency localized resonances, thereby generating multiple vibration damping bands in multiple directions along the pipeline, enabling a broadband vibration damping design. Multi-directional vibration damping can be achieved through a unidirectional arrangement of the superstructure, enabling a compact design for multi-directional, broadband vibration damping within confined spaces. The superstructure unit cells can be arbitrarily arranged around the pipeline's circumference based on the actual installation space. This not only maintains the pipeline's vibration damping performance but also potentially generates circumferential bandgap coupling, further widening the vibration damping band. The physical mechanism of circumferential bandgap coupling refers to the slight shift in the bandgap frequency band within the same plane when the superstructure unit cells are installed at different angles. These shifted bandgap frequencies, through the interference and superposition of vibration waves, create a wider overall vibration damping frequency band, surpassing the bandwidth limitations of traditional uniform arrays in the same direction. The superstructure unit cells are tunable. By adjusting parameters such as unit cell spacing and rod thickness or length, vibration damping performance can be optimized, bandgap coupling can be generated, the vibration damping frequency band can be widened, and new resonance peaks can be suppressed.

[0045] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and the embodiments. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A compact superstructure for broadband vibration suppression of a pipeline, used for vibration reduction of a pipeline body (10), characterized by: The compact superstructure includes a superstructure unit cell (30), which is installed on the outer wall of the pipe body (10). The superstructure unit cell (30) is composed of 12 mass units (320) and 30 connecting rods (31). Each of the mass units (320) is connected to 5 connecting rods (31) to form an icosahedral structure. The mass unit (320) includes a mass ball (321) and an outer wrapping layer (322) wrapped around the outer wall of the mass ball (321).

2. A compact superstructure for broadband pipeline vibration suppression according to claim 1, characterized in that: The mass ball (321) is made of metal, the outer wrapping layer (322) is made of viscoelastic material, and the connecting rod (31) is made of viscoelastic material.

3. The compact superstructure for broadband pipeline vibration suppression according to claim 1, characterized in that: The number of the superstructure unit cells (30) is multiple.

4. The compact superstructure for broadband pipeline vibration suppression according to claim 3, characterized in that: The plurality of superstructure unit cells (30) are arranged at equal intervals along the length direction of the pipe body (10), and the plurality of superstructure unit cells (30) are located in the same straight line or are evenly or unevenly distributed along the circumference of the pipe body (10).

5. The compact superstructure for broadband pipeline vibration suppression according to claim 1, characterized in that: The compact superstructure further comprises a mounting base (22) and an upper boss (210) of the base, wherein the mounting base (22) is fixed to the pipe body (10) via a clamp (40), the upper boss (210) of the base is mounted on the mounting base (22), the upper boss (210) of the base is provided with a rod-shaped slot (211) and a hemispherical slot (212), and the superstructure unit cell (30) is fixed to the rod-shaped slot (211) and the hemispherical slot (212) via an adhesive.

6. The compact superstructure for broadband pipeline vibration suppression according to claim 1, characterized in that: The superstructure unit cell (30) is a centrally symmetrical structure. The superstructure unit cell (30) has two parallel regular pentagonal planes, and the two parallel regular pentagonal planes form an angle of 36° with each other within the parallel planes.

7. The design method of a compact superstructure for broadband vibration suppression of pipelines according to claim 1, characterized in that: The following steps are involved: S1, performing a vibration test on the pipeline body (10) without any additional structure to obtain the multi-directional natural resonance frequency and amplitude X1 of the pipeline itself; S2. Preliminarily setting the geometric parameters of the superstructure unit cell (30) according to the resonance frequency of the pipeline body (10); S3. Establish a finite element model of the superstructure unit cell; S4, applying modal analysis to simulate vibration modes at different installation angles and obtaining the resonant frequencies of the superstructure unit cell (30) in various directions; S5. Determine whether the resonance frequency of the superstructure unit cell (30) covers the resonance frequency of the pipeline body (10). The judgment standard is: compare the resonance frequency of the superstructure unit cell (30) with the resonance frequency of the pipeline body (10). If the resonance frequency of the superstructure unit cell (30) completely covers the resonance frequency band of the pipeline body (10) that needs to be suppressed, proceed to the next step; if not, return to step S2, adjust the parameters of the superstructure unit cell (30), and repeat the modeling and analysis until the coverage requirement is met. S6. Install the superstructure unit cell (30) according to the actual installation space arrangement of the pipeline body (10); S7. Establish a finite element model of the superstructure pipeline; S8. Calculate the insertion loss IL of the superstructure duct. , where X2 is the amplitude of the measuring point of the superstructure pipe; S9. Verify whether the simulation results are consistent with the experimental test results. Compare the insertion loss results of the finite element simulation with the experimental test results. If the error is within the allowable range, proceed to the next step. If the error is too large, return to step S7, correct the model parameters, and recalculate and verify; S10, analyzing whether the vibration reduction performance of the superstructure pipeline meets the requirements, and determining whether the vibration reduction performance of the superstructure pipeline meets the standards. If so, proceed to the next step; if not, return to step S2 or S7, and repeat the subsequent process until the requirements are met; S11. Output superstructure design parameters and layout results.

8. The design method according to claim 7, characterized in that: In step S1, a wide-band white noise excitation is applied to the pipeline body (10) using an excitation device, a measuring point is selected at the end of the pipeline body (10), and pipeline vibration response data is collected using an acceleration sensor; In the step S2, the geometric parameters include but are not limited to the size of the superstructure unit cell (30), the length of the connecting rod (31), the material density of the mass ball (321) and the elastic modulus of the connecting rod (31); In step S3, a finite element analysis software is used to perform three-dimensional modeling on the superstructure unit cell (30), define the material properties of each component, divide the grid, and set boundary conditions. The finite element analysis software includes but is not limited to ANSYS and COMSOL; In step S6, the number of additional superstructure cells (30) is determined according to the additional quality restriction of the project, and the installation position and arrangement of the superstructure cells (30) are determined in combination with the shape of the pipeline body (10) and the installation environment; In step S7, based on the arranged superstructure pipe, an overall finite element model including the pipe body (10) and the superstructure unit cell (30) is established, and the contact settings of the connection interface between the pipe body (10) and the superstructure unit cell (30) are refined, and the contact settings include but are not limited to binding contact and friction coefficient.

9. The design method according to claim 7, characterized in that: In step S9, the error is no more than 10%.

10. The design method according to claim 7, characterized in that: In step S10, the compliance standard is based on the insertion loss of the actual experimental test being no less than 10 dB.

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