CN109087624A - A kind of magnetic based on magnetorheological materials couples active acoustical Meta Materials admittedly - Google Patents
A kind of magnetic based on magnetorheological materials couples active acoustical Meta Materials admittedly Download PDFInfo
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- CN109087624A CN109087624A CN201811083083.XA CN201811083083A CN109087624A CN 109087624 A CN109087624 A CN 109087624A CN 201811083083 A CN201811083083 A CN 201811083083A CN 109087624 A CN109087624 A CN 109087624A
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- 230000005291 magnetic effect Effects 0.000 title claims abstract description 77
- 239000000463 material Substances 0.000 title claims abstract description 69
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 7
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 7
- 230000005672 electromagnetic field Effects 0.000 claims abstract description 7
- 230000005294 ferromagnetic effect Effects 0.000 claims description 11
- 239000002245 particle Substances 0.000 claims description 11
- 238000010276 construction Methods 0.000 claims description 7
- 230000001413 cellular effect Effects 0.000 claims description 4
- 229920001971 elastomer Polymers 0.000 claims 1
- 239000000806 elastomer Substances 0.000 claims 1
- 239000010408 film Substances 0.000 abstract description 34
- 230000008859 change Effects 0.000 abstract description 3
- 239000010409 thin film Substances 0.000 abstract description 2
- 239000013013 elastic material Substances 0.000 abstract 1
- 238000009413 insulation Methods 0.000 description 18
- 238000000034 method Methods 0.000 description 5
- 239000004411 aluminium Substances 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- 239000002131 composite material Substances 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000000518 rheometry Methods 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000013536 elastomeric material Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000005562 fading Methods 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- -1 packet Include frame Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Classifications
-
- 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
-
- 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
- G10K11/162—Selection of materials
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Abstract
The present invention relates to the acoustic metamaterial technical field of low-frequency noise active control, specially a kind of magnetic based on magnetorheological materials couples active acoustical Meta Materials admittedly.This Meta Materials is that the magnetic acted on by additional electromagnetic field that a kind of magnetorheological thin-film material by annular brace frame and additional mass forms consolidates coupled structure.Annular frame structural material is made of aluminum；Magnetic current variation film is made of magnetorheological elastic material；Additional mass is made of lead material.The structure is in 500Hz frequency range below, its peak value for insulating against sound curve, which can be powered on outside under magnetic fields, to be moved, travel frequency width reaches 100Hz, by change external magnetic field intensity can be real-time, contactless control material property, to obtain the noise control of required low-frequency range.
Description
Technical field
The present invention relates to the acoustic metamaterial technical fields of low-frequency noise active control, specially a kind of to be based on magnetorheological material
The magnetic of material couples active acoustical Meta Materials admittedly.
Background technique
In modern society, the noise of low-frequency range gives it not only in the every field such as industry, aviation and traffic railway
Instrument, the equipment in field etc. bring serious security risk, and have seriously affected the daily work life of people.Existing
Low-frequency noise control method in, use the more thick and solid more complicated composite material knot of conventional concrete wall or structure
Structure, method preparation is difficult, price is higher.Low-frequency noise has it due to the features such as wavelength is long, propagation distance is remote, fading
Effect control is always the challenging problem of field of noise control.
Acoustic metamaterial is a kind of composite material of periodical sub-wavelength structure composition with negative equivalent characteristic, Ke Yitong
The too small big wavelength of size Control.In recent years, researchers propose a large amount of acoustic metamaterial, provide for low-frequency noise control
Advantageous structural model.2012, Mei Jun et al. devised a kind of hard that some asymmetry are inlaid on elastic film
The acoustic metamaterial of sheet metal realizes the high-efficiency sound insulating of low frequency region；2017, Zhou Rong et al. invented a kind of band film knot
The Helmholtz chamber acoustic metamaterial (number of patent application CN201611165543.4) of structure, so that material is below in 500Hz
Multiple sound insulation peak values are generated in frequency range.
These above-mentioned acoustic metamaterial structures have studied its sound insulation property within the scope of Frequency, these metamaterial structures
For passive type, is fixed once forming its peak value that insulates against sound, do not have adjustable characteristic.
Summary of the invention
The object of the present invention is to provide kind a kind of magnetic based on magnetorheological materials to couple active acoustical Meta Materials admittedly, by outer
Boundary magnetic field couples admittedly with the magnetic of magnetic current variation film, realizes the active Untouched control of low-frequency broadband noise.
The technical scheme is that a kind of magnetic based on magnetorheological materials couples active acoustical Meta Materials, structure list admittedly
Member is made of annular brace frame, magnetic current variation film, additional mass and additional electromagnetic field device, as illustrated in figures 1 and 8；It is attached
Mass block is added to be fixed on magnetic current variation film upper surface center, annular brace frame is divide into upper part and lower part magnetic current variation film
Be clipped in the middle fixation, then with nut surrounding stationary annular braced frame, and externally-applied magnetic field device is placed on the outside of annular brace frame
And it is located at same level, there are gap 10mm between externally-applied magnetic field device and annular brace frame；
In above scheme, the annular brace frame is made of aluminum material.
Further, the annular brace frame outer radius is 17~32mm, and inside radius is 15~30mm, with a thickness of 2
~5mm.
In above scheme, the magnetic current variation film is pasted among annular brace frame or more two parts, by magnetic current
Become elastomeric material to be made.
The further magnetic current variation film radius is 15~30mm, with a thickness of 0.5~2mm, ferromagnetic particle volume fraction
It is 10%~30%.
In above scheme, the additional mass is made of lead material.
Further, the additional mass radius is 3~6mm, with a thickness of 2~5mm.
In above scheme, the external magnetic field is controlled by electromagnetic field.
The magnetic field is radial along magnetic current variation film and passes through film.External magnetic field intensity is 0.1T~0.5T.
In above scheme, the preparation process of the active acoustical Meta Materials: the preparation process in order to simplify specimen material, it will
The magnetic based on magnetorheological materials couples active acoustical metamaterial structure admittedly and is divided into four kinds of various forms of structure divisions, point
It is not annular brace frame, magnetic current variation film, additional mass and additional electromagnetic field device, to various forms of annular frames
Hardened structure processes it using wire cutting technology, and by these structures according to upper ring frame frame plate, magnetic current variation film,
The sequence of lower ring frame frame plate is screwed from top to bottom, then mass block is fastened with glue on magnetic current variation film, most
Electromagnetic field device is fixed on structural unit periphery afterwards.
The invention has the advantages that
1. it is extraneous by changing that the magnetic of the present invention based on magnetorheological materials couples active acoustical metamaterial structure admittedly
Magnetic field strength 0.1T to 0.5T and the cellular construction geometric parameter are mutually matched: aluminium sash outer radius 17mm, and interior half
Diameter 15mm, thickness 3mm；Magnetic current variation film radius 15mm, thickness 1mm, ferromagnetic particle content 23.9%；Mass block radius 6mm is thick
2mm to be spent, optimum efficiency is reached, sound insulation crest frequency moving range reaches 87HZ or more, then it is directed to different sound insulation demands, it can
Sound insulation crest frequency of the invention is adjusted with active control magnetic field strength, is required to meet sound insulation, therefore widened sound insulation
Frequency band realizes the active control of sound insulation.
2. active acoustical metamaterial structure of the present invention is by changing magnetic field strength, real-time, reversible, contactless
To obtain wanting the noisy frequency range of control.
3. active acoustical Meta Materials individual unit structure of the present invention can reach low frequency active control purpose, nothing
Many and diverse stacking or combination are needed, the overall stability of structure arrangement efficiency and structure is improved.
4. active acoustical metamaterial structure of the present invention is simple,；Mechanical processing technique is easy, can be mass.
5. prepared by active acoustical metamaterial structure of the present invention, structure is screwed, readily removable easy dress can
It repeatedly uses, greatly reduces the difficulty of experiment assembly.
Detailed description of the invention
Fig. 1 is the active acoustical metamaterial modular construction schematic diagram of one embodiment of the invention, 1, annular brace frame；2, magnetic
Rheology film；3, additional mass.
Fig. 2 is the active acoustical metamaterial modular construction sectional view of one embodiment of the invention.
Fig. 3 is the active acoustical metamaterial unit mechanism size figure of one embodiment of the invention.
Fig. 4 is the active acoustical metamaterial modular construction simulation model figure of one embodiment of the invention.
Fig. 5 is the active acoustical Meta Materials sound insulation curve graph of one embodiment of the invention.
Fig. 6 is the active acoustical Meta Materials sound insulation property of one embodiment of the invention with magnetic current variation film ferromagnetic particle volume point
Number trend chart.
Fig. 7 is the active acoustical Meta Materials sound insulation property of one embodiment of the invention with film prestress change tendency chart.
Fig. 8 is the externally-applied magnetic field device pictorial diagram for inventing the active acoustical Meta Materials of an embodiment.
1, annular brace frame；2, magnetic current variation film, 3, additional mass.
Specific embodiment
Specific embodiments of the present invention will be described in further detail with reference to the accompanying drawing.
Fig. 1 show a kind of embodiment of active acoustical Meta Materials of the present invention and with magnetic current variation film, this hair
Bright is to replace traditional pellosil using magnetic current variation film on the basis of additional mass film frame structure, passes through external magnetic field and magnetic
The coupling of rheology film, the material parameter of active control active acoustical Meta Materials, thus active control active acoustical Meta Materials
Intrinsic frequency reaches the active control effect of low-frequency noise.Fig. 1 is the cellular construction figure of the active acoustical Meta Materials, packet
Include frame, film and mass block；Fig. 2 is the cross-sectional view of the structure of the active acoustical Meta Materials；Fig. 3 is the active acoustical Meta Materials
The dimensional drawing of structure.
As shown in Fig. 3 dimensional drawing, aluminium sash outer radius 17mm, inside radius 15mm, thickness 3mm；Magnetic current variation film half
Diameter 15mm, thickness 1mm, ferromagnetic particle content 23.9%；Mass block radius 6mm, thickness 2mm.The active acoustical Meta Materials knot
The material parameter of structure are as follows: aluminium [density p=2700kg/m3；Elastic modulus E=7E10Pa；Poisson's ratio ν=0.33]；Magnetic current is thinning
Film [density p=2100kg/m3；Elastic modulus E=6.3e6Pa；Poisson's ratio ν=0.45].
Fig. 4 show active acoustical Meta Materials of the present invention and with magnetic current variation film with COMSOL
The simulation model that " Gu sound-coupling, frequency " module calculates in Multiphysics5.1 finite element software.Face 1,2 is set as plane
Amplitude emission mode, and face 1 is plane of incidence.
Fig. 5 is the sound insulation curve graph that the active acoustical Meta Materials are calculated by COMSOL.Active Acoustic described in Fig. 5
Learn the geometric parameter of metamaterial structure are as follows: aluminium sash outer radius 17mm, inside radius 15mm, thickness 2mm；Magnetic current variation film radius
15mm, thickness 1mm, ferromagnetic particle content 23.9%；Mass block radius 6mm, thickness 2mm.
As shown in Figure 5, it under external magnetic field and magnetorheological materials coupling, is tied at 0.1T to 0.5T magnetic fields
The frequency of the sound insulation peak value of structure increases to 328Hz from 241Hz, and 0.1T corresponds to 100KA/M curve in Fig. 5,0.5T corresponds to 300KA/M
Curve, so the active acoustical Meta Materials using magnetorheological thin-film material can be special by the sound insulation of external magnetic field adjustment structure
Property, widen its sound insulation room range.
Active acoustical Meta Materials of the present invention are to reach ideal sound insulation effect, have studied different prestressing force and difference
The magnetorheological materials of ferromagnetic particle volume fraction.It keeps other parameters constant, radially applies along magnetic current variation film before measuring
Prestressing force acts on film side edge, and direction is the magnetic current variation film center of circle along radius direction film outside, has chosen prestressing force P
=188.7KPA, 260.7KPA, 353.7KPA, 417.9KPA, five kinds of pre-stressed states of 496.5KPA, have chosen Φ=5.6%,
11.8% and 23.9% 3 kind of ferromagnetic particle volume fraction magnetorheological materials.
The influence of change film prestressing force and film ferromagnetic particle volume fraction described above is as shown in fig. 6-7.With
The frequency of the increase of carbonyl iron dust volume fraction, the peak value that insulates against sound increases therewith, and the variation range for the peak value that insulates against sound is bigger, can be
Broader frequency range realizes active control.With prestressed increase, material sound insulation peak value respective frequencies also be will increase, but from
The moving range of the caused sound insulation crest frequency of magnetic field 0KA/M to 400KA/M variation remains unchanged.
A kind of magnetic based on magnetic current variation film couples the These characteristics of active acoustical metamaterial structure admittedly according to the present invention, it
It large-scale industrialized can prepare, the sound arrester that may be used as the vehicles, building can also be used as sound insulating material
In the antihunting device etc. of big machinery.
Described above is preferred embodiment, cannot function as full scope of the invention, super with acoustics of the present invention
Any be significantly improved or simple transformation belongs in patent coverage area of the invention is done on the basis of material structure.
Claims (8)
1. a kind of magnetic based on magnetorheological materials couples active acoustical Meta Materials admittedly, which is characterized in that magnetic couples active acoustical admittedly
Meta Materials are made of annular brace frame, magnetic current variation film, additional mass and additional electromagnetic field device, and additional mass is fixed
In magnetic current variation film upper surface center, annular brace frame, which is divide into upper part and lower part, is clipped in the middle magnetic current variation film admittedly
It is fixed, then nut surrounding stationary annular braced frame is used, externally-applied magnetic field device is placed on the outside of annular brace frame and positioned at same
Horizontal plane.
2. a kind of magnetic based on magnetorheological materials as described in claim 1 couples active acoustical Meta Materials admittedly, which is characterized in that
There are gap 10mm between externally-applied magnetic field device and annular brace frame.
3. a kind of magnetic based on magnetorheological materials as described in claim 1 couples active acoustical Meta Materials admittedly, which is characterized in that
The annular brace frame is made of aluminum material；The annular brace frame outer radius is 17~32mm, inside radius 15
~30mm, with a thickness of 2~5mm.
4. a kind of magnetic based on magnetorheological materials as described in claim 1 couples active acoustical Meta Materials admittedly, which is characterized in that
The magnetic current variation film is pasted among annular brace frame or more two parts, is made of magnetorheological elastomer material；Institute
Stating magnetic current variation film radius is 15~30mm, and with a thickness of 0.5~2mm, ferromagnetic particle volume fraction is 10%~30%.
5. a kind of magnetic based on magnetorheological materials as described in claim 1 couples active acoustical Meta Materials admittedly, which is characterized in that
The additional mass is made of lead material；The additional mass radius is 3~6mm, with a thickness of 2~5mm.
6. a kind of magnetic based on magnetorheological materials as described in claim 1 couples active acoustical Meta Materials admittedly, which is characterized in that
The externally-applied magnetic field that the externally-applied magnetic field device applies is radial along magnetic current variation film and passes through film, applied field strengths 0.1T
~0.5T.
7. a kind of magnetic based on magnetorheological materials as described in claim 1 couples active acoustical Meta Materials admittedly, it is characterised in that:
It is mutually matched by changing the magnetic field strength of additional electromagnetic field, and with cellular construction geometric parameter, obtains wanting making an uproar for control
Acoustic frequency range, the geometric parameter of the cellular construction include the interior outer radius of annular brace frame, thickness, magnetic current variation film
Radius, thickness, ferromagnetic particle content, mass block radius, thickness.
8. a kind of magnetic based on magnetorheological materials as described in claim 1 couples active acoustical Meta Materials admittedly, it is characterised in that:
By changing external magnetic field intensity 0.1T to 0.5T, annular brace frame outer radius 17mm, inside radius 15mm, thickness 3mm；Magnetic current
Variation film radius 15mm, thickness 1mm, ferromagnetic particle content 23.9%；Mass block radius 6mm, thickness 2mm reach optimum efficiency,
Its crest frequency moving range that insulates against sound reaches 87HZ or more.
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| CN201811083083.XA CN109087624A (en) | 2018-09-17 | 2018-09-17 | A kind of magnetic based on magnetorheological materials couples active acoustical Meta Materials admittedly |
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| CN201811083083.XA CN109087624A (en) | 2018-09-17 | 2018-09-17 | A kind of magnetic based on magnetorheological materials couples active acoustical Meta Materials admittedly |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110491360A (en) * | 2019-07-18 | 2019-11-22 | 江苏大学 | A kind of more oscillator active acoustical Meta Materials of ring-type coupled admittedly based on magnetic |
| CN111312203A (en) * | 2020-02-28 | 2020-06-19 | 清华大学 | Flexible acoustic metamaterial structure |
| CN111952064A (en) * | 2020-07-14 | 2020-11-17 | 中国科学院金属研究所 | Preparation method of magnetorheological elastomer with radially distributed magnetic particles and elastomer |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110491360A (en) * | 2019-07-18 | 2019-11-22 | 江苏大学 | A kind of more oscillator active acoustical Meta Materials of ring-type coupled admittedly based on magnetic |
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