CN111120551A - Three-negative elastic wave metamaterial with wide forbidden band - Google Patents
Three-negative elastic wave metamaterial with wide forbidden band Download PDFInfo
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- CN111120551A CN111120551A CN202010002530.5A CN202010002530A CN111120551A CN 111120551 A CN111120551 A CN 111120551A CN 202010002530 A CN202010002530 A CN 202010002530A CN 111120551 A CN111120551 A CN 111120551A
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- 239000006260 foam Substances 0.000 claims abstract description 4
- 229910052751 metal Inorganic materials 0.000 claims abstract description 4
- 239000002184 metal Substances 0.000 claims abstract description 4
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 4
- 239000010937 tungsten Substances 0.000 claims abstract description 4
- 230000000737 periodic effect Effects 0.000 claims description 6
- 239000000758 substrate Substances 0.000 claims description 5
- 239000000463 material Substances 0.000 abstract description 17
- 238000002955 isolation Methods 0.000 abstract description 9
- 230000001105 regulatory effect Effects 0.000 abstract description 3
- 230000001276 controlling effect Effects 0.000 abstract 1
- 238000009413 insulation Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 6
- 230000005540 biological transmission Effects 0.000 description 5
- 238000011160 research Methods 0.000 description 5
- 230000009467 reduction Effects 0.000 description 3
- 238000013016 damping Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000001902 propagating effect Effects 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000000644 propagated effect Effects 0.000 description 1
- 230000009323 psychological health Effects 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F3/00—Spring units consisting of several springs, e.g. for obtaining a desired spring characteristic
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F3/00—Spring units consisting of several springs, e.g. for obtaining a desired spring characteristic
- F16F3/08—Spring units consisting of several springs, e.g. for obtaining a desired spring characteristic with springs made of a material having high internal friction, e.g. rubber
- F16F3/10—Spring units consisting of several springs, e.g. for obtaining a desired spring characteristic with springs made of a material having high internal friction, e.g. rubber combined with springs made of steel or other material having low internal friction
- F16F3/12—Spring units consisting of several springs, e.g. for obtaining a desired spring characteristic with springs made of a material having high internal friction, e.g. rubber combined with springs made of steel or other material having low internal friction the steel spring being in contact with the rubber spring
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F2224/00—Materials; Material properties
- F16F2224/02—Materials; Material properties solids
- F16F2224/0225—Cellular, e.g. microcellular foam
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F2224/00—Materials; Material properties
- F16F2224/02—Materials; Material properties solids
- F16F2224/025—Elastomers
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F2228/00—Functional characteristics, e.g. variability, frequency-dependence
- F16F2228/04—Frequency effects
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F2230/00—Purpose; Design features
- F16F2230/02—Surface features, e.g. notches or protuberances
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
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Abstract
The invention discloses a three-negative elastic wave metamaterial with a wide forbidden band, which comprises N single cells. Each unit cell is of a two-dimensional structure and is square, the base material is foam, a round hole is formed in the center of the base material, and four oval holes are formed around the round hole. The four elliptical holes are filled with scatterer metal tungsten, but the scatterers cannot be filled with the elliptical holes, and the whole unit cell is of a centrosymmetric structure. The elastic wave metamaterial can simultaneously realize equivalent negative mass density, equivalent negative bulk modulus and equivalent negative shear modulus in the same frequency range, further realize negative refraction on transverse waves and longitudinal waves of elastic waves in the same frequency range, and meanwhile, the elastic wave metamaterial also has a wider forbidden band. The material can be used for designing functional devices and gradient materials for regulating and controlling elastic waves, and can also be used for vibration isolation and sound insulation of mechanical equipment and building structures.
Description
Technical Field
The invention belongs to the field of vibration reduction, and particularly relates to an elastic wave metamaterial with equivalent negative mass density, equivalent negative bulk modulus and equivalent negative shear modulus in the same frequency range.
Background
At present, in the research fields of machinery, civil engineering, instruments and the like, how to control vibration is a significant problem. For example, resonance can cause failure of components, and frequent vibration can cause accelerated fatigue failure of metal components, especially in precision instruments where precision is to be maintained without vibration interference. All vibrating objects produce sound, and the noise affects the life quality and physical and psychological health of people. Therefore, the vibration isolation and damping device has important significance for the research of vibration isolation and damping.
The theoretical basis of the elastic wave metamaterial, namely the local resonance theory, is proposed in 2000, develops on the basis of the research of phononic crystals, and has only 20 years of development history till now. Most of researches are theoretical researches, research and development work of practical functional devices is less, and the developed functional devices are generally only used in laboratories and do not enter large-scale application stages. The vibration is propagated in the form of a wave in an object, and when the wave vector propagates in an elastic wave metamaterial, there is no corresponding eigenmode in a certain frequency range, and the frequency band is called a forbidden band. The vibration isolation of the forbidden band by using the elastic wave metamaterial is one of vibration reduction and isolation means by using the elastic wave metamaterial.
Another method for reducing and isolating vibration by using metamaterials is to regulate and control the propagation path of elastic waves. The anisotropic elastic wave metamaterial can enable elastic waves with certain frequencies to bypass a target to be protected, so that the target is completely free from the influence of the elastic waves, and the elastic wave stealth cloak is provided according to the principle. The elastic wave metamaterial with the negative mass density and the negative bulk modulus can regulate and control the longitudinal wave and generate negative refraction on the longitudinal wave. The elastic wave metamaterial with the negative mass density and the negative shear modulus can regulate and control the transverse waves and generate negative refraction on the transverse waves. The elastic wave metamaterial capable of realizing negative mass density and negative bulk modulus or negative mass density and negative shear modulus in the same frequency band is called as a double negative elastic wave metamaterial. The elastic wave metamaterial capable of simultaneously realizing negative mass density, negative bulk modulus and negative shear modulus in the same frequency band can be called as a three-negative elastic wave metamaterial, and longitudinal waves and transverse waves can be regulated and controlled.
At present, double-negative elastic wave metamaterials are common, the equivalent mass density and the equivalent volume modulus of the double-negative elastic wave metamaterials in the same frequency band are negative at the same time, or the equivalent mass density and the equivalent shear modulus are negative at the same time, and the three-negative elastic wave metamaterials are rare.
Disclosure of Invention
The technical problem is as follows: the invention aims to provide a three-negative elastic wave metamaterial with a wide forbidden band, wherein a unit cell of the three-negative elastic wave metamaterial has a wider band gap than a unit cell of the same type. The forbidden band can prevent a part of elastic waves from propagating, the propagation path of the elastic waves which cannot be prevented by the forbidden band can be regulated and controlled by utilizing negative refraction, and according to the principle, the three negative elastic wave metamaterials can be used for manufacturing a vibration reduction and isolation function gradient material or a functional device. The three negative elastic wave metamaterials are negative in equivalent mass density, equivalent volume modulus and equivalent shear modulus in the same frequency band, can realize negative refraction of longitudinal waves and transverse waves, and can regulate and control the propagation paths of the longitudinal elastic waves and the transverse elastic waves.
The technical scheme is as follows: in order to achieve the purpose, the technical scheme of the three negative elastic wave metamaterial with the wide forbidden band is as follows:
the metamaterial comprises N single cells, each single cell is of a two-dimensional structure and is square, a round hole is formed in the center of a single cell base body, four elliptical holes are formed around the round hole, scatterers filled in the four elliptical holes cannot be filled in the elliptical holes, gaps are left, the whole single cell is of a central symmetrical structure, and the single cell is extended in the x and y directions of a two-dimensional coordinate system to form a two-dimensional periodic structure.
Wherein:
the axes of the long axes of the four elliptical holes pass through the center of a circular hole formed in the center of the unit cell substrate, and the four elliptical holes are uniformly distributed on the periphery of the circular hole.
The scatterers filled in the four elliptical holes are positioned on one side of the central circular hole.
The unit cell is extended in the x and y directions of a two-dimensional coordinate system to form a two-dimensional periodic structure, wherein the axes of the long axes of the elliptical holes are respectively on a straight line in the transverse direction or the longitudinal direction.
The material of the substrate is foam, and the material of the scatterer is metal tungsten.
Has the advantages that:
1. the invention relates to a three-negative elastic wave metamaterial with a wide forbidden band, which has equivalent negative mass density, equivalent negative bulk modulus and equivalent negative shear modulus in the same frequency band, can generate negative refraction on longitudinal waves and transverse waves, and further regulates and controls the propagation path of elastic waves.
2. The invention is a periodic structure, has an elastic wave forbidden band, and the forbidden band width is higher than that of the same three negative elastic wave metamaterials.
3. The invention has three negative parameters and a wider forbidden band, the forbidden band can prevent the elastic wave in the frequency range of the forbidden band from transmitting, and for the elastic wave which can not be prevented by the forbidden band, the elastic wave can be diffracted by utilizing the characteristic of negative refraction, so that the elastic wave can not be transmitted to a target to be protected. According to the principle, a functional gradient material or a functional device with the vibration isolation function can be manufactured. Unlike vibration isolators which can only be fabricated using forbidden bands or negative refraction properties, the present invention can utilize the forbidden bands and negative refraction properties of materials simultaneously, increasing the frequency band range over which elastic waves can be prevented from propagating.
Drawings
FIG. 1 is a schematic diagram of the extension process of a single cell of a three-negative elastic wave metamaterial with a wide forbidden band according to the present invention;
FIG. 2 is a schematic diagram of a single unit cell of a three-negative elastic wave metamaterial with a wide bandgap according to the present invention;
FIG. 3 shows an example of a design of a unit cell according to the invention; (a) the design drawing is a three-negative elastic wave metamaterial unit cell with a wide forbidden band, (b) is an energy band structure drawing of the unit cell, (c) is a metamaterial band composed of the unit cell and used for calculating the transmission of the three-negative elastic wave metamaterial composed of the unit cell, (d) is a transmission curve diagram of the metamaterial band;
FIG. 4 shows the present invention applied to a functionally graded material with vibration isolation; (a) the invention is a functional gradient material schematic diagram which can change the propagation path of elastic wave, (b) is the functional gradient material with vibration isolation function which is applied to the invention;
among them are: a substrate 1, a scatterer 2 and a gap 3; an elliptical hole major axis D1, an elliptical hole minor axis D2, a diffuser width, D3, a distance D4 from the elliptical hole to the center of the substrate, and a radius R of the circular hole.
Detailed Description
The present invention will be further described with reference to the accompanying drawings.
As shown in fig. 1 and 2: a three-negative elastic wave metamaterial with a wide forbidden band comprises N single cells. Each unit cell is of a two-dimensional structure and is square, the base body 1 is made of foam, a round hole is formed in the center of the base body, and four oval holes are formed around the round hole. The four elliptical holes are filled with scatterers 2 made of tungsten, the scatterers cannot fill the elliptical holes, gaps 3 are reserved, the whole unit cell is of a central symmetrical structure and extends in the x and y directions to form a two-dimensional periodic structure, and the thickness in the z direction takes any value.
Example 1: as shown in fig. 3, fig. 3(a) is a design diagram of a three-negative elastic wave metamaterial unit cell with a wide forbidden band, where a is 6mm, R is 1mm, and D is1＝1.6mm，D2＝0.6mm，D3＝0.8mm，D40.3 mm. FIG. 3(b) is a diagram of the energy band structure of the unit cell, and three negative parameters appear in the overlapped part of the 5 th and 6 th negative energy band bands (which can be proved by observing the displacement intrinsic fields of the two energy bands). The second forbidden band width of the unit cell is about 4.5kHz and is higher than the forbidden band width of the same kind. FIG. 3(c) shows a three-negative elastic wave metamaterial band composed of ten unit cells, and the transmission curve calculated by the model is shown in FIG. 3(d), wherein the transmission rate of longitudinal wave and transverse wave is higher in the overlapping part of the 5 th and 6 th band bands, and the elastic wave in the forbidden bandThe transmission rate is extremely low.
Example 2: as shown in FIG. 4, FIG. 4(a) is a functionally graded material that can bend the elastic wave path to propagate in an arc, and it can be seen that the first layer is made of a negatively refracting metamaterial. Applying the unit cell of FIG. 2 to the first layer of functionally graded material of FIG. 4(a) results in a new functionally graded material as shown in FIG. 4 (b). The functional gradient material formed by the three negative elastic wave metamaterials has a forbidden band, can prevent the propagation of elastic waves within the frequency of the forbidden band, and can prevent elastic waves with certain frequencies which cannot be prevented by the forbidden band from influencing the target to be protected by bending the propagation path of the elastic waves, so that the functional gradient material can utilize the forbidden band and the passband to jointly isolate vibration.
Claims (5)
1. A three-negative elastic wave metamaterial with a wide forbidden band is characterized in that: the metamaterial comprises N single cells, each single cell is of a two-dimensional structure and is square, a round hole is formed in the center of a single cell base body (1), four elliptical holes are formed around the round hole, scatterers (2) filled in the four elliptical holes are arranged, the scatterers (2) cannot be filled in the elliptical holes, gaps (3) are reserved, the whole single cell is of a central symmetric structure, and the single cell is extended in the directions of a two-dimensional coordinate system x and y to form a two-dimensional periodic structure.
2. The three-negative elastic wave metamaterial with a wide forbidden band according to claim 1, wherein: the axes of the long axes of the four elliptical holes pass through the center of a circular hole formed in the center of the unit cell substrate (1), and the four elliptical holes are uniformly distributed on the periphery of the circular hole.
3. The three-negative elastic wave metamaterial with a wide forbidden band according to claim 1 or 2, wherein: the scatterer (2) filled in the four elliptical holes is positioned on one side of the central circular hole.
4. The three-negative elastic wave metamaterial with a wide forbidden band according to claim 1 or 2, wherein: the unit cell is extended in the x and y directions of a two-dimensional coordinate system to form a two-dimensional periodic structure, wherein the axes of the long axes of the elliptical holes are respectively on a straight line in the transverse direction or the longitudinal direction.
5. The three-negative elastic wave metamaterial with a wide forbidden band according to claim 1, wherein: the base body (1) is made of foam, and the scatterer (2) is made of metal tungsten.
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| CN202010002530.5A CN111120551A (en) | 2020-01-02 | 2020-01-02 | Three-negative elastic wave metamaterial with wide forbidden band |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113158525A (en) * | 2021-04-28 | 2021-07-23 | 北京理工大学 | Broadband elastomer wave separation device based on five-mode material and design method thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013133175A1 (en) * | 2012-03-05 | 2013-09-12 | 国立大学法人京都工芸繊維大学 | Three-dimensional meta-material |
| CN106205586A (en) * | 2016-07-11 | 2016-12-07 | 武汉理工大学 | A kind of metal-based foam fills broad band low frequency gap elasticity Meta Materials |
| CN106777822A (en) * | 2017-01-22 | 2017-05-31 | 河海大学 | Two-dimentional high-content particle strengthens composite three-phase meso-mechanical model and method for building up |
| CN108447467A (en) * | 2018-03-30 | 2018-08-24 | 重庆速阔智能科技有限公司 | A kind of active acoustical metamaterial structure unit and its control device |
| CN108520739A (en) * | 2018-03-28 | 2018-09-11 | 贵州大学 | A kind of impedance transition mechanism type acoustic stimulation based on locally resonant principle |
| CN109658913A (en) * | 2019-01-10 | 2019-04-19 | 浙江大学 | A kind of soft phonon crystal of stretchable regulation band gap |
-
2020
- 2020-01-02 CN CN202010002530.5A patent/CN111120551A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013133175A1 (en) * | 2012-03-05 | 2013-09-12 | 国立大学法人京都工芸繊維大学 | Three-dimensional meta-material |
| CN106205586A (en) * | 2016-07-11 | 2016-12-07 | 武汉理工大学 | A kind of metal-based foam fills broad band low frequency gap elasticity Meta Materials |
| CN106777822A (en) * | 2017-01-22 | 2017-05-31 | 河海大学 | Two-dimentional high-content particle strengthens composite three-phase meso-mechanical model and method for building up |
| CN108520739A (en) * | 2018-03-28 | 2018-09-11 | 贵州大学 | A kind of impedance transition mechanism type acoustic stimulation based on locally resonant principle |
| CN108447467A (en) * | 2018-03-30 | 2018-08-24 | 重庆速阔智能科技有限公司 | A kind of active acoustical metamaterial structure unit and its control device |
| CN109658913A (en) * | 2019-01-10 | 2019-04-19 | 浙江大学 | A kind of soft phonon crystal of stretchable regulation band gap |
Non-Patent Citations (1)
| Title |
|---|
| 吴吉恩: "三负声超常材料设计", "人工复合结构对弹性波的超常调控及其应用设计", no. 2019, pages 8 - 15 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113158525A (en) * | 2021-04-28 | 2021-07-23 | 北京理工大学 | Broadband elastomer wave separation device based on five-mode material and design method thereof |
| CN113158525B (en) * | 2021-04-28 | 2022-07-05 | 北京理工大学 | Broadband elastomer wave separation device based on five-mode material and design method thereof |
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Inventor after: Wan Shui Inventor after: Wang Xiao Inventor after: Fu Jundong Inventor after: Zhou Peng Inventor after: Shen Jiwei Inventor after: Su Qiang Inventor after: Nian Yuze Inventor after: Li Xiayuan Inventor after: Huang Muyun Inventor before: Wan Shui Inventor before: Wang Xiao Inventor before: Fu Jundong Inventor before: Zhou Peng Inventor before: Shen Jiwei Inventor before: Su Qiang Inventor before: Nian Yuze Inventor before: Li Xiayuan Inventor before: Huang Muyun |