Equipment vibration and noise reduction method based on acoustic metamaterial

Abstract

The invention relates to an equipment vibration and noise reduction method based on an acoustic metamaterial, and the method comprises the steps: analyzing a vibration source and vibration signal characteristics according to the operation state of equipment, determining the vibration source, and determining a required frequency band for vibration and noise reduction; finite element software is used for carrying out acoustic metamaterial structure design based on the local resonance principle, and the noise reduction frequency band and the noise reduction depth are adjusted by adjusting the geometric size, the vibrator arrangement mode and material selection of a local resonance structure; preparing a sample piece according to the design scheme, and verifying a simulation result and an actual result; after verification is completed, the prepared sample piece is installed at a specified installation node according to user requirements, and the prepared sample piece and the to-be-processed equipment form an integrated structure; verifying whether the frequency response curve of the integrated structure after the local resonance structure is installed accords with the theoretical design or not; and finally, the equipment equipped with the local resonance structure is applied to actual life and production.

Description

Technical Field

[0001] The present invention relates to the technical field of acoustic metamaterials and vibration reduction and noise reduction, and in particular to a method for equipment vibration reduction and noise reduction based on acoustic metamaterials. Background Art

[0002] In the world's rapid technological development and the ever-changing industrial structure upgrade, high-end equipment, as a national heavy equipment, highlights a country's core competitiveness. In the manufacturing, operation and maintenance of equipment, vibration and noise levels have become important influencing factors and evaluation indicators, and even become the core competitiveness of products. In the equipment manufacturing process, the isolation of vibration and noise in the processing environment and the vibration control of machine tools and other processing equipment are crucial to ensure the accuracy and quality of equipment. As equipment develops in the direction of high speed, light weight and precise control, the vibration and noise problems in the operation of equipment are becoming increasingly prominent. Strong vibration will not only endanger the physical and mental health of the human body, but also affect the operating life and control accuracy of the equipment. In severe cases, it may directly lead to serious accidents such as loss of control, structural fatigue fracture, and explosion.

[0003] In the context of lightweight, integrated and intelligent modern industrial products, traditional vibration and noise reduction methods mainly use nylon materials or dynamic vibration absorbers to attenuate and absorb elastic waves. Due to the strong penetration of low-frequency vibration and noise, traditional vibration and noise reduction are subject to many limitations in controlling low-frequency vibration and noise. Not only is the low-frequency control effect poor, but there are often defects such as large additional mass, difficulty in adjustment, and impact on equipment heat dissipation, which are contrary to the lightweight and integrated nature of the equipment. In addition, traditional vibration and noise reduction methods often redesign the structure of the equipment, greatly increasing the time and space costs of equipment vibration and noise reduction processing.

[0004] In recent years, as a new type of structural material with special physical properties, the study of elastic wave characteristics in acoustic metamaterials has received widespread attention. This new type of structural material is mainly composed of periodically arranged artificial structural units. By artificially designing the structural size and arrangement of periodic units on a subwavelength scale, the unique physical properties of unconventional materials - negative equivalent mass density and negative equivalent elastic modulus - are achieved. These extraordinary physical properties can be used to control sound and vibration to achieve the purpose of reducing vibration and noise. Summary of the invention

[0005] In order to overcome the shortcomings and deficiencies in the prior art, the purpose of the present invention is to provide a method for vibration reduction and noise reduction of equipment based on acoustic metamaterials. By utilizing the flexibility, adjustability, lightweight and other advantages of the local resonance structure, an integrated packaging structure is designed in combination with the target requirements, and the vibration isolation and overall vibration reduction and noise reduction of the equipment are achieved through this structure, so as to prevent local vibration of the equipment from affecting the working state of the rest of the equipment.

[0006] The purpose of the present invention is achieved through the following technical solution: A method for reducing vibration and noise of equipment based on acoustic metamaterials, comprising the following steps:

[0007] S1. Analyze the vibration source and vibration signal characteristics during the operation of the equipment. According to the displacement frequency response curve, vibration transfer curve, energy band curve in different frequency bands, and the modal vibration shapes of each order of the device, clarify the main weakening frequency range of the sound pressure level or amplitude and other vibration and noise reduction requirements;

[0008] S2. Structural design of acoustic metamaterials based on the principle of local resonance. According to the mechanism and influence of band gap generation and the characteristics of typical spring-mass systems, the designable and adjustable parameters mainly include geometric structure dimensions, vibrator arrangement and material selection. According to user needs, finite element software is used to design the local resonance structure so that it can meet the requirements of vibration reduction and noise reduction in the corresponding application scenarios.

[0009] S3, preparing a sample using the structural dimensions of the local resonance metamaterial designed in step S2 to obtain a local resonance structure;

[0010] S4. Determine the effective installation node according to user needs, and stick the local resonance structure on the surface to be damped to form an integrated device;

[0011] S5. Check the vibration frequency response curve of the integrated device in step S4 by a vibration analyzer to ensure that the actual value is consistent with the theoretical value;

[0012] S6. Apply the integrated device to actual life or production.

[0013] Preferably, the specific steps of structural design of acoustic metamaterial based on the local resonance principle in step S2 include the following steps:

[0014] Step 1: Modeling: Use geometric modeling tools to design the parameters of the local resonance structure, ensure that the geometric model meets the actual research needs, and perform integrated simulation of the equipment where the local resonance structure is placed;

[0015] Step 2, material addition: select the material of the corresponding component in the material library of the finite element analysis software, and import the density, Young's modulus, Poisson's ratio, and damping values ​​of the material, and select the corresponding areas to add materials;

[0016] Step 3, boundary conditions: set the boundary conditions of the model, including fixed constraints, free supports, and steady-state excitation forces, to simulate the real working environment of the local resonance structure;

[0017] Step 4: Mesh division: ensure that the model has sufficient accuracy in simulation calculation while maintaining calculation efficiency;

[0018] Step 5: Parametric study: Set the parameter variation and conduct a parametric study of the structural vibration characteristics under different conditions.

[0019] Preferably, the spring-mass system is a typical equivalent model of a local resonance structure, and the main influencing parameters of the band gap characteristics of the local resonance structure are the equivalent mass and equivalent stiffness of the equivalent model.

[0020] Preferably, in step S2, the local resonance structure comprises a resonator, a cladding layer and a substrate, the cladding layer is arranged on the substrate, and the resonator is arranged on the upper end surface of the cladding layer.

[0021] Preferably, the local resonance structure is designed by the following method:

[0022] (1) Geometric parameters: The geometric parameters of the resonator include the shape and size of the resonator. The geometric parameters of the cladding layer are selected according to the resonator, and the resonator is embedded in the cladding layer and maintained at a certain height. The parameters of the substrate are thickness and shape. The shape is irregular due to different application scenarios and resonator arrangements.

[0023] (2) Physical parameters: Physical parameters include density, Poisson's ratio and Young's modulus. The changes of these three main parameters are adjusted by the material selection of the local resonance structure;

[0024] (3) Spatial arrangement: The spatial arrangement is mainly determined by the arrangement of the resonators and the substrate material. The material shape of the substrate is determined by the orientation of the equipment in which it is located. The substrate must be arranged without affecting the normal operation of the equipment.

[0025] Preferably, the material of the resonator is one or more of 304 stainless steel, 6061 aluminum, and H62 copper; the material of the coating layer is silica gel with a hardness of 5%, 10% or 20%.

[0026] The resonator described in the present invention is a key component of the local resonance structure, and the parameters of the resonator match the elastic wavelength of a specific vibration frequency. During the propagation of elastic waves, the resonator can effectively interact with the elastic wave, causing the resonator to resonate. This resonance phenomenon causes unconventional acoustic effects within a specific vibration frequency range, such as negative mass, negative stiffness, etc. This part is usually made of metal materials, including but not limited to 304 stainless steel, 6061 aluminum, and H62 copper. The specific vibration frequency is the frequency band corresponding to the band gap of the local resonance acoustic material. In this frequency band, the elastic wave is severely attenuated, usually below -20dB.

[0027] Preferably, the material of the substrate is a high molecular polymer or a composite material.

[0028] The coating layer in the present invention is an outer layer that wraps or covers the resonator, and its function is to protect the resonator and affect the propagation characteristics of sound waves. The coating layer can adjust the frequency response of the metamaterial by changing the properties, thickness or structure of the material. In addition, the coating layer can also provide mechanical support and structural stability of the metamaterial to ensure its performance and durability in use. Silica gel is usually selected as the material for making the coating layer. The substrate is a supporting structure of the local resonance structure, usually located at the bottom of the resonator and the coating layer. The raw material selection and design of the substrate depends on the application environment and requirements of the metamaterial, and the material usually used is epoxy resin.

[0029] The arrangement mainly includes but is not limited to: triangular arrangement, quadrilateral arrangement, and hexagonal arrangement.

[0030] The available models of the silica gel include: E610#, E620#, and E630#, and the hardness after hardening is 10%, 20%, and 30% respectively.

[0031] Preferably, the resonators are arranged in a circular surround or rectangular array and are provided in a single layer or multiple layers.

[0032] Preferably, the shape of the resonator is a cone, a cylinder or a sphere, and the design of the size of the resonator includes parameters related to length, width, height and radius.

[0033] Preferably, the local resonance structure is arranged in an "I" shape. According to the application scenario of the local resonance structure, the "I" shape can be used as a bearing structure of the local resonator and as a reinforcing rib to strengthen the structural rigidity of the equipment and increase the reliability of the equipment.

[0034] Preferably, the sizes and dimensions of the resonators and the cladding layers in the local resonance structure in the same application are the same, and they are arranged with the same spacing.

[0035] Preferably, in the same application, the local resonance structures are arranged in a rectangular array, and are arranged in a 2*n arrangement on each side of the "I"-shaped base plate.

[0036] The installation node in step S4 of the present invention is determined by the modal vibration shape and modal frequency. The modal vibration shape and modal frequency are inherent characteristics of the system, which describe the deformation mode of the structure at a specific frequency. Under different modes, the amplitude of vibration and the distribution of energy will be different. Higher-order modes (such as second order, third order, etc.) may have a vibration intensity greater than the first-order mode due to resonance, excitation position, or geometric structure and boundary factors. Therefore, it is necessary to perform finite element simulation on the lighting effect control device to determine the area with the largest vibration intensity, and determine the installation position of the acoustic metamaterial based on the area. The parameters of the local resonance structure are determined by the vibration reduction and noise reduction frequency band determined in step S1. Finite element simulation is performed with the goal of reducing the vibration amplitude in the target frequency band by adjusting the geometric dimensions, physical parameters, and spatial arrangement of the local resonance structure.

[0037] The spatial distribution and structural arrangement of the local resonance structure adopts an "I"-shaped arrangement, that is, the local resonance cells are arranged on an "I"-shaped substrate. The substrate serves as a bearing structure for the local resonator on the one hand, and as a reinforcing rib or reinforcing rib of the equipment on the other hand, to increase the structural rigidity of the equipment and increase the reliability of the equipment.

[0038] Technical principle of the present invention:

[0039] When the elastic wave frequency approaches the natural frequency of the local resonator, the dynamic response amplitude of the mass block in the local resonator increases, the propagation amplitude of the elastic wave in the main structure decreases, and the acoustic metamaterial forms an elastic wave band gap structure. The starting and ending frequencies of the local resonance band gap can be given by the following formula.

[0040] In the formula, k R and m R Represent the stiffness and mass of the local resonator, respectively; M represents the mass of the matrix in the acoustic metamaterial cell. The frequency and width of the local resonance band gap are related to the properties of the local resonator, and using a small-scale and supportive matrix structure to open the band gap structure in the low-frequency region provides a potential way.

[0041] As for the linear spring-mass local resonator, its external size is large, and there is a contradiction between the load-bearing capacity and low stiffness of the linear spring, which makes it difficult to apply the local resonator in engineering practice. By replacing the linear spring with elastic materials or elastic structures, a compact local resonator can be constructed. One advantage of using elastic structures instead of linear springs is that elastic materials can provide restoring forces in multiple directions at the same time. Therefore, the local resonator composed of elastic structures can open different types of elastic wave band gaps, such as longitudinal wave band gaps, bending wave band gaps, and torsional wave band gaps.

[0042] The beneficial effects of the present invention are:

[0043] 1. High space utilization: Compared with traditional vibration-damping materials such as rubber and foam, the local resonance structure occupies less space, greatly improving the space utilization of the equipment.

[0044] 2. Frequency selective control: The local resonance structure can achieve highly selective control of vibration and noise within a specific frequency range by reasonably designing the resonator. The local resonance structure can be adjusted according to the needs of different environments and working conditions to achieve precise control of specific frequencies.

[0045] 3. Versatility: The local resonance structure can not only be used for vibration control, but also play a role in noise control. This versatility enables it to deal with vibration and noise problems more comprehensively in complex environments.

[0046] 4. Easy installation: The local resonance structure is prepared in an integrated manner and can be simply pasted on the required equipment when used.

[0047] 5. High practicality: No additional energy input is required, high efficiency and energy saving; suitable for multiple industries, can play a role in aerospace, construction, automobile and other fields, and provide innovative solutions for vibration and noise reduction in these industries.

[0048] 6. Low production cost: The local resonance structure is manufactured using relatively economical materials, such as alloys, polymers, etc., and can be mass-produced on a large scale in actual production applications, thereby reducing the production cost of each unit.

[0049] 7. Long life and low maintenance cost: Once the design of metamaterials meets engineering requirements, they usually have a long service life and low maintenance cost, which greatly reduces the total cost of the overall life cycle of metamaterials.

[0050] 8. Partitioned vibration isolation: Through the arrangement of local resonance structures, the arrangement of local resonance structures on the equipment can be adjusted according to application requirements to achieve partitioned vibration isolation. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a flow chart of the vibration reduction and noise reduction method of the present invention;

[0052] Figure 2 It is the structural intention of the local resonance structure in the present invention;

[0053] Figure 3 is a schematic diagram of a lighting effect control panel of a lamp in Example 2;

[0054] Figure 4 is a schematic diagram of a lamp lighting effect control panel in which a local resonance structure is arranged in Example 2;

[0055] Figure 5is a design flow chart of the local resonance structure in Example 2;

[0056] Figure 6 It is a comparison diagram of the vibration acceleration response curves of a lighting effect control board of a certain lamp before and after the local resonance structure is installed in Example 2.

[0057] The reference numerals in the drawings are: 1-resonator, 2-cladding layer, 3-substrate, 4-motor, 5-first rail portion, 6-second rail portion. DETAILED DESCRIPTION

[0058] In order to facilitate the understanding of those skilled in the art, the following embodiments and attached Figure 1-6 The present invention is further described, and the contents mentioned in the implementation modes are not intended to limit the present invention.

[0059] Example 1

[0060] See Figure 1 , 2 The purpose of the present invention is achieved through the following technical solution: A method for reducing vibration and noise of equipment based on acoustic metamaterials, comprising the following steps:

[0061] S1. Analyze the vibration source and vibration signal characteristics during the operation of the equipment. According to the displacement frequency response curve, vibration transfer curve, energy band curve in different frequency bands, and the modal vibration shapes of each order of the device, clarify the main weakening frequency range of the sound pressure level or amplitude and other vibration and noise reduction requirements;

[0062] S2. Structural design of acoustic metamaterials based on the principle of local resonance. According to the mechanism and influence of band gap generation and the characteristics of typical spring-mass systems, the designable and adjustable parameters mainly include geometric structure dimensions, vibrator arrangement and material selection. According to user needs, finite element software is used to design the local resonance structure so that it can meet the requirements of vibration reduction and noise reduction in the corresponding application scenarios.

[0063] S3, preparing a sample using the structural dimensions of the local resonance metamaterial designed in step S2 to obtain a local resonance structure;

[0064] S4. Determine the effective installation node according to user needs, and stick the local resonance structure on the surface to be damped to form an integrated device;

[0065] S5. Check the vibration frequency response curve of the integrated device in step S4 by a vibration analyzer to ensure that the actual value is consistent with the theoretical value;

[0066] S6. Apply the integrated device to actual life or production.

[0067] Preferably, the specific steps of structural design of acoustic metamaterial based on the local resonance principle in step S2 include the following steps:

[0068] Step 1: Modeling: Use geometric modeling tools to design the parameters of the local resonance structure, ensure that the geometric model meets the actual research needs, and perform integrated simulation of the equipment where the local resonance structure is placed;

[0069] Step 2, material addition: select the material of the corresponding component in the material library of the finite element analysis software, and import the density, Young's modulus, Poisson's ratio, and damping values ​​of the material, and select the corresponding areas to add materials;

[0070] Step 3, boundary conditions: set the boundary conditions of the model, including fixed constraints, free supports, and steady-state excitation forces, to simulate the real working environment of the local resonance structure;

[0071] Step 4: Mesh division: ensure that the model has sufficient accuracy in simulation calculation while maintaining calculation efficiency;

[0072] Step 5: Parametric study: Set the parameter variation and conduct a parametric study of the structural vibration characteristics under different conditions.

[0073] The spring-mass system is a typical equivalent model of a local resonance structure, and the main influencing parameters of the band gap characteristics of the local resonance structure are the equivalent mass and equivalent stiffness of the equivalent model.

[0074] In step S2 , the local resonance structure includes a resonator 1 , a cladding layer 2 and a substrate 3 , wherein the cladding layer 2 is disposed on the substrate 3 , and the resonator 1 is disposed on the upper end surface of the cladding layer 2 .

[0075] The local resonance structure is designed by the following method:

[0076] (1) Geometric parameters: The geometric parameters of the resonator 1 include the shape and size of the resonator 1; the geometric parameters of the coating layer 2 are selected according to the resonator 1, and the resonator 1 is embedded in the coating layer 2 and maintained at a certain height; the parameters of the substrate 3 are thickness and shape, wherein the shape is irregular due to different application scenarios and arrangements of the resonator 1;

[0077] (2) Physical parameters: Physical parameters include density, Poisson's ratio and Young's modulus. The changes of these three main parameters are adjusted by the material selection of the local resonance structure;

[0078] (3) Spatial arrangement: The spatial arrangement is mainly determined by the arrangement of the resonator 1 and the material of the substrate 3. The material shape of the substrate 3 is determined by the orientation of the equipment in which it is located. The substrate 3 must be arranged without affecting the normal operation of the equipment.

[0079] The material of the resonator 1 is one or more of 304 stainless steel, 6061 aluminum, and H62 copper; the material of the coating layer 2 is silicone with a hardness of 5%, 10% or 20%.

[0080] The material of the substrate 3 is a high molecular polymer or a composite material.

[0081] The arrangement mainly includes but is not limited to: triangular arrangement, quadrilateral arrangement, and hexagonal arrangement.

[0082] The available models of the silicone include: E610#, E620#, E630#, and the hardness after hardening is 10%, 20%, and 30% respectively.

[0083] The resonators 1 are arranged in a circular surround or rectangular array and are provided in a single layer or multiple layers.

[0084] The shape of the resonator 1 is a cone, a cylinder or a sphere, and the size design of the resonator 1 includes parameters related to length, width, height and radius.

[0085] The local resonance structure is arranged in an "I" shape. According to the application scenario of the local resonance structure, the "I" shape can be used as a bearing structure of the local resonator and as a reinforcing rib to strengthen the structural rigidity of the equipment and increase the reliability of the equipment.

[0086] In the local resonance structure in the same application, the size and dimensions of the resonator 1 and the cladding layer 2 are the same and arranged with the same spacing.

[0087] In the same application, the local resonance structures are arranged in a rectangular array, and are arranged in a 2*n arrangement on each side of the "I"-shaped base 3 plate.

[0088] The spatial distribution and structural arrangement of the local resonance structure adopts an "I"-shaped arrangement, that is, the local resonance cells are arranged on the "I"-shaped substrate 3. The substrate 3 serves as a bearing structure for the local resonator on the one hand, and as a reinforcing rib or reinforcing rib of the equipment on the other hand, to increase the structural rigidity of the equipment and increase the reliability of the equipment.

[0089] Example 2

[0090] Taking the vibration noise suppression of a lamp equivalent control panel as an example, the implementation process is as follows:

[0091] A method for reducing vibration and noise of equipment based on acoustic metamaterials comprises the following steps:

[0092] S1. Vibration source analysis: Analyze the vibration source during the operation of the lighting effect control board of the lamp, and determine the main vibration frequency and signal characteristics;

[0093] S2. Demand analysis and vibration reduction scheme design: Based on the analysis in step S1, determine the frequency range that requires vibration reduction, and design a suitable local resonance structure based on the principle of structural design of acoustic metamaterials in combination with the principle of local resonance to achieve vibration reduction within the target frequency range;

[0094] S3. Local resonance structure design: Use finite element simulation analysis software to design the structure of the acoustic metamaterial, including the geometric parameters and material properties of the resonator 1, the cladding layer 2 and the substrate 3, and optimize the local resonance structure through finite element software so that it can achieve vibration suppression within the corresponding frequency band;

[0095] S4, preparation of acoustic metamaterial samples: according to the local resonance structure designed in step S3, prepare the corresponding structure samples, and paste the samples on the lighting effect control board for preparation;

[0096] S5. Paste and integrate the local resonance structure: According to the location and frequency of the vibration source, select the appropriate installation node, paste the local resonance structure on the surface of the lighting effect control board, and ensure that the local resonance structure and the lighting effect control board form an integrated structure to effectively isolate and weaken the vibration;

[0097] S6. Experiment and debugging: Use a vibration analyzer to measure the actual vibration frequency response curve and compare it with the theoretical value during design. According to the experimental results, make necessary adjustments and optimizations to the local resonance structure to ensure that the vibration reduction effect meets expectations.

[0098] S7, system integration and testing: Integrate the optimized lighting effect control board into the lighting system, conduct comprehensive tests on the system to ensure that the vibration reduction and noise reduction effects have no negative impact on the normal operation of the entire lighting system;

[0099] S8. Performance verification and application: Verify whether the vibration reduction and noise reduction effects meet the design requirements, apply the lighting control board with local resonance structure to actual lamps, and observe and evaluate the vibration reduction and noise reduction effects in actual use environment.

[0100] The local resonance structure is as follows Figure 2 As shown, it includes a resonator 1, a coating layer 2 and a substrate 3, wherein the coating layer 2 is arranged on the substrate 3, and the resonator 1 is arranged on the upper end surface of the coating layer 2. The main parameters of the resonator 1 include geometric dimensions, physical parameters, and arrangement mode; the coating layer 2 is made of silica gel, and the designable parameter is the hardness of the silica gel; the material of the substrate 3 is mainly selected from high molecular polymers, such as polycarbonate engineering plastics.

[0101] The lighting effect control panel is as follows Figure 3As shown, the main vibration sources are four motors 4 located at the four corners of the plate for heat dissipation of the equipment. During the operation of the motors 4, interference is caused to the first track portion 5 and the second track portion 6 in the middle, causing the track to bend and vibrate, which has a negative impact on the accurate and efficient operation of the track control components. The main function of the present invention is to isolate and suppress the vibration caused by the operation of the motors 4 through the parameter design and spatial arrangement of the local resonance structure, so as to ensure the smooth operation of the control components of the first track portion 5 and the second track portion 6 in the middle, and at the same time suppress the structural vibration of the entire lighting effect control board.

[0102] The structural design process of the local resonance acoustic metamaterial in step S3 is as follows: Figure 5 As shown, the specific steps are as follows:

[0103] (1) Geometric modeling: The parameters of the local resonance acoustic metamaterial are designed using the geometric modeling tool of the finite element simulation analysis software. The designed resonator 1 is a cylinder. The main geometric parameters involved include the height and radius of the resonator 1. The spatial arrangement adopts a hollow rectangular arrangement, so that the local resonance structure cells are arranged around the lighting effect control track structure of the lamp;

[0104] (2) Material addition: Select the material of the corresponding component in the material library of the finite element simulation analysis software, and set the material properties, including density, Young's modulus, and Poisson's ratio. During the design process, the main materials available are 304 stainless steel, H62, and 6061 aluminum.

[0105] (3) Boundary conditions: Set the boundary conditions of the model, including fixed constraints and free branches, to simulate the real working environment of the local resonance structure;

[0106] (4) Meshing: ensuring that the model has sufficient accuracy in simulation calculations while maintaining computational efficiency;

[0107] (5) Parametric study: Set the parameter variation and conduct parametric study on the structural vibration characteristics under different conditions. Based on the research results, infer the relationship between the local resonant structure parameters and the corresponding frequency response curve to obtain a local resonant structure that meets the application conditions.

[0108] The arrangement of the local resonance structure is designed according to the results of the equipment vibration analysis, and can be installed in an "I" shape. While the local resonance structure plays a role in reducing vibration and noise, it also plays a role in reinforcing ribs, enhancing the strength and rigidity of the components, so as to save material usage, reduce weight, and reduce costs. The local resonance cell materials are evenly arranged on the "I"-shaped base 3 material, and the horizontal and vertical spacings are both 10mm. The cell arrays on each side of the "I" shape are arranged in a 2*n manner, that is, the cell arrangements are all arranged in two rows. Using this arrangement method can reduce the space occupied in the equipment as much as possible, and at the same time can prevent the local resonance structure from affecting the track components of the equipment and the normal operation of the motor 4.

[0109] The vibration acceleration response curves of the equipment without and with the local resonance structure are shown in the figure below. Figure 6 As shown in the figure, the “I”-shaped arrangement and the uniform array arrangement of the local resonance cells make the equipment have good vibration reduction performance in the frequency range of 0 to 2kHz. The vibration acceleration response is significantly reduced at the peak, and the lower peak near the main peak is eliminated due to the loss of the vibrator and damping material, so that the vibration acceleration signal of the final equipment is reduced both overall and locally, and the overall vibration reduction and noise reduction effect is good.

[0110] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention may also be implemented in other ways. Any obvious replacement without departing from the concept of the present invention is within the protection scope of the present invention.

Claims

1. A method for reducing vibration and noise of equipment based on acoustic metamaterials, characterized in that: The steps include: S1. Analyze the vibration source and vibration signal characteristics during the operation of the equipment, and identify the main weakening frequency range of the sound pressure level or amplitude and other vibration and noise reduction requirements; S2. Design the structure of acoustic metamaterials based on the principle of local resonance. According to the mechanism and influence of band gap generation and the characteristics of a typical spring-mass system, finite element software is used to design the local resonance structure so that it can meet the requirements of vibration reduction and noise reduction in the corresponding application scenarios. S3, preparing a sample using the structural dimensions of the local resonance metamaterial designed in step S2 to obtain a local resonance structure; S4. Determine the effective installation node according to user needs, and stick the local resonance structure on the surface to be damped to form an integrated device; S5. Check the vibration frequency response curve of the integrated device in step S4 by a vibration analyzer to ensure that the actual value is consistent with the theoretical value; S6. Apply the integrated device to actual life or production.

2. According to claim 1, a method for reducing vibration and noise of equipment based on acoustic metamaterials is characterized by: The specific steps of structural design of acoustic metamaterial based on the local resonance principle in step S2 include the following steps: Step 1: Modeling: Use geometric modeling tools to design the parameters of the local resonance structure, ensure that the geometric model meets the actual research needs, and perform integrated simulation of the equipment where the local resonance structure is placed; Step 2, material addition: select the material of the corresponding component in the material library of the finite element analysis software, and set the material properties, including density, Young's modulus, and Poisson's ratio; Step 3, boundary conditions: set the boundary conditions of the model, including fixed constraints and free branches, to simulate the real working environment of the local resonance structure; Step 4: Mesh division: ensure that the model has sufficient accuracy in simulation calculation while maintaining calculation efficiency; Step 5: Parametric study: Set the parameter variation and conduct a parametric study of the structural vibration characteristics under different conditions.

3. According to claim 1, a method for reducing vibration and noise of equipment based on acoustic metamaterials is characterized by: In step S2, the local resonance structure includes a resonator, a cladding layer and a substrate, the cladding layer is arranged on the substrate, and the resonator is arranged on the upper end surface of the cladding layer.

4. The equipment vibration reduction and noise reduction method based on acoustic metamaterials according to claim 1, characterized in that: The local resonance structure is designed by the following method: (1) Geometric parameters: The geometric parameters of the resonator include the shape and size of the resonator. The geometric parameters of the cladding layer are selected according to the resonator, and the resonator is embedded in the cladding layer and maintained at a certain height. The parameters of the substrate are thickness and shape. The shape is irregular due to different application scenarios and resonator arrangements. (2) Physical parameters: Physical parameters include density, Poisson's ratio and Young's modulus. The changes of these three main parameters are adjusted by the material selection of the local resonance structure; (3) Spatial arrangement: The spatial arrangement is mainly determined by the arrangement of the resonators and the substrate material. The material shape of the substrate is determined by the orientation of the equipment in which it is located. The substrate must be arranged without affecting the normal operation of the equipment.

5. The equipment vibration reduction and noise reduction method based on acoustic metamaterials according to claim 3 or 4, characterized in that: The material of the resonator is one or more of 304 stainless steel, 6061 aluminum, and H62 copper; the material of the coating layer is silica gel with a hardness of 5%, 10% or 20%; the material of the substrate is a high molecular polymer or a composite material.

6. The equipment vibration reduction and noise reduction method based on acoustic metamaterials according to claim 4, characterized in that: The resonators are arranged in a circular surround or rectangular array and are provided in a single layer or multiple layers.

7. The equipment vibration reduction and noise reduction method based on acoustic metamaterials according to claim 4, characterized in that: The shape of the resonator is a cone, a cylinder or a sphere, and the design of the size of the resonator includes parameters related to length, width, height and radius.

8. The equipment vibration reduction and noise reduction method based on acoustic metamaterials according to any one of claims 3 to 7, characterized in that: The local resonance structure is arranged in an "I" shape.

9. The equipment vibration reduction and noise reduction method based on acoustic metamaterials according to any one of claims 3 to 7, characterized in that: In the local resonance structure in the same application, the size and dimensions of the resonator and the cladding layer are the same and arranged with the same spacing.

10. The equipment vibration reduction and noise reduction method based on acoustic metamaterials according to any one of claims 3 to 7, characterized in that: In the same application, the local resonance structures are arranged in a rectangular array, and are arranged in a 2*n arrangement on each side of the "I"-shaped base plate.

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