CN111833835A - Super-cell unit capable of forming line defect periodic composite structure - Google Patents
Super-cell unit capable of forming line defect periodic composite structure Download PDFInfo
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- CN111833835A CN111833835A CN202010435193.9A CN202010435193A CN111833835A CN 111833835 A CN111833835 A CN 111833835A CN 202010435193 A CN202010435193 A CN 202010435193A CN 111833835 A CN111833835 A CN 111833835A
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- 239000000463 material Substances 0.000 claims description 16
- 238000003466 welding Methods 0.000 claims description 3
- 238000002955 isolation Methods 0.000 abstract 1
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/002—Devices for damping, suppressing, obstructing or conducting sound in acoustic devices
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
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Abstract
The invention relates to a cluster of super-cells capable of forming a periodic composite structure with line defects, wherein the cluster of super-cells comprises 8 types A-H. Wherein each super cell comprises a substrate (1) and scatterer elements (2) arranged on the substrate (1) in a quasi-periodic arrangement; by combining these super cells with each other, a periodic composite structure having a line defect characteristic can be formed. The periodic composite structure itself has a band gap characteristic, and vibrations in a specific frequency range cannot propagate through the structure. The introduction of the defect structure changes the original energy band structure of the periodic composite structure, so that the elastic wave with the frequency corresponding to the defect state can only propagate along the line defect. Therefore, the periodic composite structure with the linear defect characteristic provides an effective way for controlling elastic waves by utilizing an artificial structure, and has important value in the fields of engineering vibration isolation, waveguides, acoustic wave filters and the like.
Description
Technical Field
The present invention relates to a cluster of super-cells, and more particularly, to a cluster of super-cells capable of forming a periodic composite structure with line defects.
Background
With the rapid development of the economy and the society, the vibration and noise problems generated in the aspects of transportation, mechanical operation, human life and entertainment, building construction and the like are increasingly and widely concerned. The conventional vibration suppression methods mainly include passive control, active control, and the like, depending on whether the use of energy is required or not.
Scientists in the 90 s of the 20 th century discovered that the propagation of acoustic-elastic waves on elastic materials with periodic structures resulted in the failure of elastic waves to propagate in a certain frequency range, and therefore proposed the concept of phononic crystals (periodic composite structures). The phononic crystal is a structure which is periodically arranged by taking unit cells as basic units, namely the density and the elasticity parameters of the material are periodically distributed. The phononic crystal is characterized in that elastic waves in a specific frequency range can be greatly attenuated to be incapable of being transmitted through the phononic crystal, and the frequency range is called as a band gap of the phononic crystal; for other frequencies than the band gap, the elastic wave can theoretically continue to propagate through the phononic crystal without loss, these frequency ranges are called the passband of the phononic crystal, and the ranges of the forbidden band and the passband can be adjusted accordingly by changing the parameters of the structure, the material and the like of the phononic crystal. The characteristic of the phononic crystal just makes up the defects of the traditional vibration suppression methods such as passive control, active control and the like, and is a good way and method for solving noise and vibration.
Introducing defects into the phononic crystal, such as changing the size, shape, material, etc. of some scatterers, phononic bands, called defect bands, may appear in the band gap of the original defect-free crystal, and the corresponding states are called defect states. The distribution of the defect-state acoustic wave has locality, i.e., the acoustic wave is confined to propagate near the defect. The localization of the defect states of the phononic crystal is of practical value, for example, for acoustic filters and acoustic waveguides. If the defects in the phononic crystal are distributed on a line, then it is called a line defect phononic crystal, there may be a defect band where the acoustic wave propagates only along the line defect, and the energy of the defect mode is locally propagated in the line defect, thus constituting an acoustic waveguide. Therefore, the research on the defect state of the phononic crystal provides an effective way for controlling waves by utilizing an artificial structure, and has great significance for the design and manufacture of acoustic devices such as an acoustic filter, an acoustic waveguide and the like.
Disclosure of Invention
The technical problem is as follows: the invention aims to provide a cluster of super-cells capable of forming a periodic composite structure with line defects, wherein the periodic composite structure with the line defects is formed by mutually combining several super-cells, so that elastic waves with defect frequencies can only propagate along the line defects in a matrix, and elastic waveguide is realized.
The technical scheme is as follows: the inventive super-cell cluster can form line defect periodic composite structure with A, B, C, D, E, F, G, H kinds, wherein each super-cell comprises a substrate and common scatterer oscillator arranged on the substrate in quasi-periodic arrangement.
And the base body is also provided with a defect scatterer vibrator.
The common scatterer vibrator is in a shape of a cylinder, a cuboid or a regular polygon.
The common scatterer vibrator is a single component or two components, and the arrangement mode on the substrate is an embedded type, a single-side convex type or a double-side convex type.
The shapes, the number of components, the arrangement mode, the size and the materials of the common scatterer vibrators are the same.
The common scatterer vibrators are two components, and when the common scatterer vibrators are arranged on the base body according to a convex mode, the radius or the side length of the inner layer vibrators and the radius or the side length of the outer layer vibrators are equal, and the height of the inner layer vibrators and the height of the outer layer vibrators are equal or different.
When the defect scatterer vibrator exists, one or more of the shape, the number of components, the arrangement mode, the size and the material of the defect scatterer vibrator and the common scatterer vibrator are different.
And when the base body and the common scatterer vibrator or the defect scatterer vibrator or the common scatterer vibrator and the defect scatterer vibrator are two components, the inner layer of the vibrator and the outer layer of the vibrator are connected in a sticking or welding mode.
Has the advantages that: compared with the prior art, the invention has the following advantages:
1) the periodic structure has the band gap characteristic, and the elastic wave in the band gap frequency range is remarkably inhibited from propagating in the periodic composite structure, so that the formed periodic composite structure can achieve the aim of vibration reduction.
2) In the periodic composite structure with the line defects formed by the cluster of super-cells, the elastic wave with the defect frequency can only be transmitted along the line defects, and the elastic waveguide can be realized.
3) The traditional elastic wave or acoustic wave calibration element has large size and high manufacturing cost, and the periodic composite structure with line defects formed by the super-cell unit cluster can reduce the size and the manufacturing cost. Meanwhile, the manufacturing is convenient, and the standardized production is convenient.
Drawings
FIG. 1 is a top view of a cluster of super-cell elements of a two-component cuboid-shaped conventional scatterer vibrator, a single-component cylindrical defect scatterer vibrator embedded on a substrate;
fig. 2 is a schematic diagram of a cluster of super-cell elements in which a two-element cylindrical common scatterer oscillator is not present, and the two-element cylindrical common scatterer oscillator is arranged on a substrate in a protruding manner;
FIG. 3 is a schematic view of a linear defect-cycle composite structure formed by 6C-type super cells and 3B-type super cells according to the present invention;
FIG. 4 is a schematic view of a zigzag defect period composite structure formed by 1B-type super cell, 5C-type super cell, 1D-type super cell, 1E-type super cell and 1F-type super cell according to the present invention;
fig. 5 is a schematic diagram of a branched defect cycle composite structure formed by 1 a-type super cell, 1B-type super cell, 3C-type super cell, 1D-type super cell, 1 and E-type super cell, 1G-type super cell and 1H-type super cell according to the present invention;
FIG. 6 is a schematic diagram of the propagation of elastic waves at defect frequencies in a linear periodic composite structure of defects according to the present invention.
The figure shows that: the device comprises a base body 1, a common scatterer vibrator 2-1 and a defect scatterer vibrator 2-2.
h1Is of a common convex typeHeight of inner layer of the vibrator h when the vibrator of the scatterer is two-component2When the common convex scatterer vibrator is a two-component vibrator, the height of the outer layer of the vibrator, e is the thickness of the substrate,
D0is the diameter of a cylindrical, generally convex diffuser, D1Is the diameter of a cylindrical, generally embedded diffuser, D2Is the diameter of the cylindrical defect-embedded scatterer,
d1is the outer side length, d, of a square, generally embedded diffuser2Is the inner edge length of a square, generally embedded scatterer, and a is the lattice constant.
Detailed Description
The periodic composite structure, also called phononic crystal, refers to a periodic material or structure with acoustic or elastic wave band gap, and its internal elastic constant and density are periodically changed. In terms of material composition, the phononic crystal may be a solid/solid, solid/fluid or fluid/fluid system, or may be a single material system formed by periodically opening pores on a material substrate. The background material which is communicated with each other in the phononic crystal is a matrix, the material which is not communicated with each other is a scatterer, and both the matrix and the scatterer can be solid, liquid or gas. The distance between two adjacent minimal repeating units (unit cells) is called the lattice constant.
Introducing defects into a phononic crystal having a periodic structure, such as changing the size, shape, material, etc. of some scatterers, phononic bands, called defect bands, may appear in the band gap of the original defect-free crystal, and the corresponding states are called defect states. The distribution of the defect-state acoustic wave has locality, i.e., the acoustic wave is confined to propagate near the defect. The localization of the defect states of the phononic crystal is of practical value, for example, for acoustic filters and acoustic waveguides. If the defects in the phononic crystal are distributed on a line, then it is called a line defect phononic crystal, there may be a defect band where the acoustic wave propagates only along the line defect, and the energy of the defect mode is locally propagated in the line defect, thus constituting an acoustic waveguide.
The forming method of the invention is as follows:
the cluster of super-cells comprises 8A-H super-cells, each super-cell comprises a substrate, a common scatterer oscillator and a defect scatterer oscillator, wherein the defect scatterer oscillator can exist or not exist. The scatterer vibrator can be a single component or two components, is embedded in the base body or arranged in a protruding mode, and can be cylindrical, rectangular or regular polygonal. The shape, the number of components, the arrangement mode, the size and the material of the common scatterer vibrator are the same. And one or more of the shape, the number of components, the arrangement mode, the size and the material of the defect scatterer vibrator are different from those of the common scatterer vibrator. When the base body and the scatterer vibrator or the scatterer vibrator is two-component, the inner layer of the vibrator and the outer layer of the vibrator are connected in a sticking or welding mode. By combining several types of super-cells, a linear, zigzag or branched defect periodic composite structure can be formed.
The invention will be further described in detail by way of example with reference to the accompanying drawings in which:
example 1:
as shown in fig. 1, the present embodiment is a cluster of super-cells in which scatterer elements are embedded on a substrate, and the total number of the super-cells is 8. The lattice constant of each super cell is a. The scatterer vibrators are distributed on the base plate in a quasi-periodic manner, the common scatterer vibrator is a cuboid with two components, and the side lengths of squares on the top surfaces of the inner layer and the outer layer are respectively d1And d2The defect scatterer is a single-element cylinder with a diameter D2. The vibrator outer layer and the base body as well as the inner layer vibrator and the outer layer vibrator adopt a bonding connection mode.
Example 2:
as shown in fig. 2, the present embodiment is a cluster of super-cells with scatterer oscillators protruding on the substrate, and the total number of the super-cells is 8. The lattice constant of each super cell is a. The scatterer vibrators are distributed on the base plate in a quasi-periodic manner, the common scatterer vibrator is a two-component cylinder, and the heights of the inner layer and the outer layer are h1And h2All diameters being D0Defect scatterers are not present. The height of the substrate is e. The connection mode of sticking is adopted between the inner layer of the vibrator and the base body and between the inner layer vibrator and the outer layer vibrator.
Example 3:
as shown in fig. 3, the present embodiment is a periodic composite structure with linear defects formed by combining 6C-type super cells and 3B-type super cells 3 × 3. The lattice constant of the super-cell is a, the vibrator of the scatterer is in a single-component cylinder shape, and the diameters of the common scatterer and the defect scatterer are D respectively1And D2And the substrate is embedded and distributed. The vibrator and the base plate are connected in a sticking mode.
Example 4:
as shown in fig. 4, the present embodiment is a periodic composite structure with zigzag defects formed by combining 1B-type super cell, 5C-type super cell, 1D-type super cell, 1E-type super cell and 1F-type super cell. The lattice constant of the super-cell is a, the vibrator of the scatterer is in a single-component cylinder shape, and the diameters of the common scatterer and the defect scatterer are D respectively1And D2And the substrate is embedded and distributed. The vibrator and the base plate are connected in a sticking mode.
Example 5:
as shown in fig. 5, the present embodiment is a periodic composite structure with branch type defects formed by combining 1 a-type super cell, 1B-type super cell, 3C-type super cell, 1D-type super cell, 1 and E-type super cell, 1G-type super cell and 1H-type super cell. The lattice constant of the super-cell is a, the vibrator of the scatterer is in a single-component cylinder shape, and the diameters of the common scatterer and the defect scatterer are D respectively1And D2And the substrate is embedded and distributed. The vibrator and the base plate are connected in a sticking mode.
As shown in fig. 6, when an elastic wave with a defect frequency is incident on a periodic composite structure with line defect characteristics, the energy band structure of the periodic composite structure is changed, the elastic wave with the defect frequency can only propagate along the path of the line defect, and the energy of the defect mode is locally propagated in the line defect to form a waveguide.
The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.
Claims (8)
1. A cluster of super-cells forming a periodic composite structure with line defects, characterized in that the cluster of super-cells comprises A, B, C, D, E, F, G, H types, each type of super-cell comprises a substrate (1) and ordinary scatterer elements (2-1) arranged in a quasi-periodic arrangement, protruding or embedded on the substrate (1).
2. The cluster of super cells forming a periodic composite structure with line defects as defined in claim 1, wherein the substrate (1) is further provided with defect scatterer elements (2-2).
3. The cluster of super-cells forming a periodic composite structure with line defects as defined in claim 1, wherein the regular scatterer elements (2-1) are in the shape of a cylinder, a cuboid or a regular polygon.
4. The cluster of supercell capable of forming periodic composite structures with line defects according to claim 1, wherein the ordinary scatterer vibrator (2-1) is a single component or a two-component, and is arranged on the substrate (1) in an embedded type, a single-side bump type or a double-side bump type.
5. The cluster of super-cells capable of forming a periodic composite structure with line defects as set forth in claim 1, wherein the shapes, the number of components, the arrangement, the size and the materials of the ordinary scatterer elements (2-1) are the same.
6. The super cell cluster capable of forming a periodic composite structure with line defects as claimed in claim 1, wherein the ordinary scatterer transducers (2-1) are two-component, and when arranged on the substrate (1) in a convex manner, the inner layer transducers and the outer layer transducers have equal radius or side length and equal or unequal height.
7. The super cell cluster capable of forming a periodic composite structure with line defects according to claim 2, wherein when the defect scatterer vibrator (2-2) exists, one or more of the shape, the number of components, the arrangement, the size and the material of the defect scatterer vibrator (2-2) and the common scatterer vibrator (2-1) are different.
8. The super cell cluster capable of forming the line defect periodic composite structure according to claim 1, wherein when the base body (1) and the common scatterer vibrator (2-1), the defect scatterer vibrator (2-2) or the common scatterer vibrator (2-1) and the defect scatterer vibrator (2-2) are two components, the connection mode of pasting or welding is adopted between the inner layer of the vibrator and the outer layer of the vibrator.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113067498A (en) * | 2021-03-01 | 2021-07-02 | 同济大学 | Multilayer plate energy harvesting structure based on defect state acoustic metamaterial |
| CN113108002A (en) * | 2021-04-23 | 2021-07-13 | 天津大学 | Stereo-form phononic crystal vibration isolation and noise reduction device with particle damping characteristic |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1670481A (en) * | 2005-04-07 | 2005-09-21 | 东南大学 | Optical gyroscope made from quantum crystal and method for making same |
| TW200844520A (en) * | 2007-05-04 | 2008-11-16 | Univ Nat Kaohsiung Applied Sci | Photonic crystal with a coupling-filtering structure |
| US7733198B1 (en) * | 2007-05-15 | 2010-06-08 | Sandia Corporation | Microfabricated bulk wave acoustic bandgap device |
| CN108980248A (en) * | 2018-07-25 | 2018-12-11 | 华东交通大学 | It is a kind of that the vibration isolation bump leveller that shakes is led based on particle damping and the track plates of phonon crystal |
| CN109377977A (en) * | 2018-11-29 | 2019-02-22 | 南京航空航天大学 | The piezo-electric type phonon crystal plate of active control propagation path and its application |
| CN212380102U (en) * | 2020-05-21 | 2021-01-19 | 东南大学 | Super-cell unit capable of forming line defect periodic composite structure |
-
2020
- 2020-05-21 CN CN202010435193.9A patent/CN111833835A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1670481A (en) * | 2005-04-07 | 2005-09-21 | 东南大学 | Optical gyroscope made from quantum crystal and method for making same |
| TW200844520A (en) * | 2007-05-04 | 2008-11-16 | Univ Nat Kaohsiung Applied Sci | Photonic crystal with a coupling-filtering structure |
| US7733198B1 (en) * | 2007-05-15 | 2010-06-08 | Sandia Corporation | Microfabricated bulk wave acoustic bandgap device |
| CN108980248A (en) * | 2018-07-25 | 2018-12-11 | 华东交通大学 | It is a kind of that the vibration isolation bump leveller that shakes is led based on particle damping and the track plates of phonon crystal |
| CN109377977A (en) * | 2018-11-29 | 2019-02-22 | 南京航空航天大学 | The piezo-electric type phonon crystal plate of active control propagation path and its application |
| CN212380102U (en) * | 2020-05-21 | 2021-01-19 | 东南大学 | Super-cell unit capable of forming line defect periodic composite structure |
Non-Patent Citations (3)
| Title |
|---|
| 李凤莲;: "二维正方晶格声子晶体的缺陷态分析", 北京信息科技大学学报(自然科学版), no. 06, 15 December 2015 (2015-12-15), pages 32 - 36 * |
| 李建宝: "声子晶体带隙调控的数值与实验研究", 中国博士学位论文全文数据库 基础科学辑, no. 09, 15 September 2011 (2011-09-15), pages 83 - 99 * |
| 马天雪: "声光子晶体结构中的波传播及声光耦合作用研究", 中国博士学位论文全文数据库 工程科技Ⅰ辑, no. 06, 15 June 2017 (2017-06-15), pages 24 - 25 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113067498A (en) * | 2021-03-01 | 2021-07-02 | 同济大学 | Multilayer plate energy harvesting structure based on defect state acoustic metamaterial |
| CN113108002A (en) * | 2021-04-23 | 2021-07-13 | 天津大学 | Stereo-form phononic crystal vibration isolation and noise reduction device with particle damping characteristic |
| CN113108002B (en) * | 2021-04-23 | 2022-12-13 | 天津大学 | Stereo-form photonic crystal vibration isolation and noise reduction device with particle damping characteristic |
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