CN104681021A - Magnetic-field-adjustable low-frequency sound insulation structure and sound insulation material - Google Patents

Magnetic-field-adjustable low-frequency sound insulation structure and sound insulation material Download PDF

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Publication number
CN104681021A
CN104681021A CN201510070456.XA CN201510070456A CN104681021A CN 104681021 A CN104681021 A CN 104681021A CN 201510070456 A CN201510070456 A CN 201510070456A CN 104681021 A CN104681021 A CN 104681021A
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sound insulation
magnetic
magnetic field
matrix
proton
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CN201510070456.XA
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钱炜
王晓乐
李龙光
黄震宇
叶杰明
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Shanghai Jiaotong University
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Shanghai Jiaotong University
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Abstract

The invention discloses a magnetic-field-adjustable low-frequency sound insulation structure which comprises a matrix, a magnetic proton and a soft material, wherein the periphery of the matrix is sealed; a through hole is formed in the middle of the matrix; the magnetic proton is embedded into the through hole of the matrix; and the soft material is adhered in a gap between the matrix and the magnetic proton, and fixedly connected with the matrix and the magnetic proton respectively. When an external disturbance sound wave is incident to the surface of the sound insulation structure, corresponding vibration is excited, a resonance peak and an anti-resonance peak can be found via spectral analysis, and a frequency band near the anti-resonance peak has a better sound insulation effect. An external magnetic field can control stress of a magnetic material and a soft material in a structure unit, thereby moving a position of the anti-resonance peak. Within an elastic range of a material, the larger the magnetic field is, the larger the movement of a sound insulation peak is, so that the sound insulation peak of the material can move to be identical with frequency of outside noise by adjusting the magnitude of the external magnetic field according to frequency distribution and change of the outside noise, and a very good active sound insulation effect is achieved.

Description

A kind of controllable magnetic field sound insulation room structure and sound insulating material
Technical field
The present invention relates to low-frequency sound insulating material technical field, specifically a kind of controllable magnetic field sound insulation room structure and sound insulating material.
Background technology
Intercept the travel path of noise by inserting material or absorb the energy consuming noise, the method that the acoustic energy after by material is reduced, is called sound insulation.Usually by oise insulation factor, material sound-insulation capability is inherently described, it is defined as: noise is by the acoustic energy ratio before and after material, namely the ratio of incident acoustic energy and perspective acoustic energy is taken the logarithm the decibels obtained, and is also called transmission loss, and conventional sign R or TL (dB) represents.
Since reform and opening-up, the process of industrialization high speed development of China, causes serious noise pollution while bringing high economic benefit, and its Middle and low frequency noise is the most serious to the harm of human body.The auditory system of main damage human body and nervous system.The source of low-frequency noise mainly comprises elevator, transformer, central air conditioner and traffic noise.According to the quality theorem of classics, sound insulation for traditional sound insulating material high-frequency domain can reach good effect, but it is poor for the attenuating of low-frequency sound wave, energy attenuation is slow, penetration power is strong, propagation distance is far away, causes the sound insulation and noise reducing for low-frequency sound wave to become a still unsolved thorny engineering roadblock.
On the Science periodical of 2000, the people such as Liu Zhengyou propose the concept of locally resonant type phonon crystal first.In literary composition, proposition gel coated shot is arranged in epoxy resin-base according to simple cubic lattice, theoretical and experiment all demonstrates the low bandgap that this structure has about 400Hz, reduces two orders of magnitude than the first bandgap frequency of the Bragg scatter-type phonon crystal of same size.This discovery achieves small size and controls large wavelength, provides new thinking to solution low-frequency vibration noise problem.
According to Ampere theorem, magnetic field can be produced around electrified wire, hot-wire coil is often used to produce the nonuniform magnetic fields with gradient in experiment, nonuniform magnetic fields acts on magnetic mass unit can produce a power, this power can change the position of magnetic mass unit and flexible material by tension force situation, thus change whole elastomeric equivalent stiffness, and then affect the Vibration Condition of magnetic mass unit and the sound insulation peak frequency range of lower frequency region.
Magnetic material, according to the complexity of degaussing after magnetization, can be divided into soft magnetic material and retentive material.Hard magnetic material not easily demagnetizes after referring to magnetization and can retain a kind of material of magnetic for a long time.Conventional permanent magnetic material has rare earth permanent-magnetic material, Permanent magnet metallics, ferrite permanent-magnet materials.
Existing sound insulation room Meta Materials, its physical characteristics just cannot be changed once sizing, all effectively can only completely cut off a certain frequency range of low-frequency sound wave, be difficult to be applicable to outside noise complicated and changeable.
Summary of the invention
Object of the present invention is overcoming above-mentioned the deficiencies in the prior art, a kind of controllable magnetic field sound insulation room structure and sound insulating material are provided, artificially can isolate the noise effect of a certain any low-frequency range, namely can optionally initiatively decay to low frequency noise, efficient and be easy to realize.
In order to solve the problem, technical solution of the present invention is as follows:
A kind of controllable magnetic field sound insulation room structure, its feature is, comprise: the matrix that all round closure and middle part have through hole, the flexible material being embedded in the magnetic proton in the through hole of this matrix and being attached between described matrix and magnetic proton gap, this flexible material is fixedly connected with described matrix, magnetic proton respectively.
Described matrix is that the hard material being greater than 1Gpa by Young modulus is made.
Described flexible material layer is that the flexible material being less than 1Gpa by Young modulus is made.
Described flexible material is silicon rubber or styrene-butadiene rubber.
Described magnetic proton is made up of hard magnetic material or soft magnetic material.
The consistency of thickness of described matrix and flexible material layer, and between 1mm-10mm.
The radius of described magnetic proton is no more than 10mm.
A kind of controllable magnetic field low-frequency sound insulating material, is rearranged by one or more above-mentioned controllable magnetic field sound insulation room structural periodicity.
External magnetic field is produced by hot-wire coil or permanent magnet, can by changing the space structure of coil, and the position of electrical current size direction or permanent magnet changes the gradient in magnetic field.By regulating the gradient magnitude of external magnetic field, elastomeric equivalent elastic coefficient can be changed, thus change resonant frequency of the present invention, and then change the crest frequency at antiresonance and high oise insulation factor place.
Compared with prior art, the present invention has following beneficial effect:
1) optionally can carry out active attenuation to low frequency noise, conveniently by the position adjusting externally-applied magnetic field size or permanent magnet, change the frequency range of high oise insulation factor.
2) by regulating weight and the magnetization of magnetic material, the efficiency of oise insulation factor peak value frequency range movement can be regulated.
3) structural design is simple, is easy to mass processing and manufactures.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of controllable magnetic field sound insulation room structure of the present invention.
Fig. 2 is the schematic diagram of the direction of applied field strengths B when being parallel to the direction of the power F suffered by permanent magnet.
Fig. 3 is the equivalent physical model of Fig. 2.
Sample oise insulation factor curve spectrogram when Fig. 4 is different magnetic field size.
Fig. 5 is microphone standing-wave-tube method proving installation schematic diagram.
Embodiment
For making object of the present invention and technical scheme clearly understand, below in conjunction with embodiment also with reference to accompanying drawing, the present invention will be described in detail.
With reference to Fig. 1, Fig. 1 is the schematic diagram of controllable magnetic field sound insulation room structure of the present invention, as shown in the figure, a kind of controllable magnetic field sound insulation room structure, comprise: the matrix 1 that all round closure and middle part have through hole, the flexible material 2 being embedded in the magnetic proton 3 in the through hole of this matrix and being attached between described matrix and magnetic proton 3 gap, this flexible material 2 is fixedly connected with described matrix, magnetic proton respectively.
Be greater than the hard material of 1Gpa as matrix by Young modulus, and be fixedly connected on external device or on framework.So-called Young modulus is the parameter of exosyndrome material elasticity coefficient.The implication be fixedly connected with write in the present invention is exactly that this connected mode can ensure relative motion can not occur between bi-material, comprises and fixing with glue or screw.The thickness of matrix is between 1mm-10mm.
The material that Young modulus is less than 100Mpa can be used as the soft material of filling, and can be solid also can be poroid, and soft material includes but not limited to styrene-butadiene rubber and silicon rubber etc., and hard material adopts with soft material contact portion and is fixedly connected with.The thickness of soft material is consistent with hard material.
The magnetic proton be embedded in soft material selects magnetic material, comprises hard magnetic material and soft magnetic material.The shape of magnetic proton can be but be not limited to cylindrical, spherical, square etc.Magnetic proton is fixedly connected with soft material, comprises when to connect with glue and prepare and directly being solidified in soft material by magnetic substance.The thickness of magnetic proton or diameter are between 0.1mm-10mm.The magnetic property quantum count embedded in soft material is not limit.
A kind of controllable magnetic field low-frequency sound insulating material, is rearranged by one or more above-mentioned controllable magnetic field sound insulation room structural periodicity.
Preparation method of the present invention is as follows:
1. Young modulus is greater than the thin plate of the harder material of 1Gpa, takes to hole or the mode such as milling is molded into matrix with through hole.By acetone soln cleaning matrix and magnetic property sub-surface, thus can be firm with silica gel adhesion.
2. smear one deck adhesion promotor at matrix and magnetic property sub-surface, in ventilated environment static 15 minutes, treat that it is dry.
3. place the soft rubber magnetic sheet that a piece has more weak magnetic in the below of matrix, put into the magnetic proton fixed position of through hole so that follow-up.The polar alignment of magnetic proton can arbitrary arrangement.
4. configure liquid-state silicon gel and pour into, allowing liquid-state silicon gel be full of space between magnetic proton and matrix.
5. structure is put into vacuum constant-temperature container, take out repeatedly vacuum, the steam bubble in silica gel is discharged completely.Vacuum constant-temperature container is put temperature 50 degree, heat 600 minutes, solidify to make silica gel.
5. take out and clear up the silica gel of excess surface, removing soft rubber magnetic sheet, prepare complete.
Fig. 2 is the schematic diagram of the direction of applied field strengths B when being parallel to the direction of the power f suffered by permanent magnet, Fig. 3 is the equivalent physical model of Fig. 2, namely the mechanical model schematic diagram of a negative mass unit in the spring mass system that described sound insulating material is corresponding, wherein f is the power in propagation process of sound wave suffered by unit, k is the elasticity coefficient of soft material, d is the displacement of magnetic material corresponding outer ring hard material, and M is the quality of magnetic material.When magnetic direction and magnet are consistent by external magnetic field force direction, f-kd-f can be obtained according to Newton second law mag=-Mw 2d, according to the definition of equivalent mass, F tot=-M effw 2d, these two formula of simultaneous can obtain M eff=m (1-w c 2/ w 2), wherein resonant frequency can be obtained by Maxwell equation, magnetic field force f mag=Mu 0e ▽ H, wherein, μ 0 is permeability of vacuum, and H is magnetic field intensity, and ▽ H is the gradient of magnetic field intensity, and E is the magnetization of magnetic material.Therefore, namely by regulating the gradient magnitude of external magnetic field, elastomeric equivalent elastic coefficient can be changed, thus change resonant frequency, thus also can change the crest frequency at antiresonance and high oise insulation factor place.The magnetic field that hot-wire coil or permanent magnet produce is easy to regulation and control, and has the advantages such as noncontact.Added external magnetic field direction can be, but not limited to parallel with the direction of magnetic proton or contrary.The forced vibration pattern of magnetic proton and soft material is changed by externally-applied magnetic field, thus the frequency location that controlled material sound insulation peak value is corresponding, reach the object that efficiently initiatively insulates against sound easily.
Fig. 5 is microphone standing-wave-tube method proving installation schematic diagram, in figure, and S 1be the distance between No. 1 microphone and No. 2 microphones, S 2be the distance between No. 3 microphones and No. 4 microphones, d 1and d 2be respectively sample front surface to the distance between second and the 3rd microphone, the sound source that represents A incides the acoustical signal of sample surfaces, the acoustical signal of B representative sample surface reflection, C represent into the acoustical signal of transmission after sample, D represents the weak acoustic signal that standing wave tube end reflection is returned.Based on ASTM (American Society for Testing and Materials, U.S. material with test association) E2611-09: the oise insulation factor testing standard of employing four microphone standing-wave-tube method to material of " Standard test method for measurement of normal incidence sound transmission of acoustical materials based on the transfer matrix method " is tested, and can obtain the oise insulation factor size at each frequency place of material.
Implementation result: utilize the frequency range of software to magnetic field regulation and control oise insulation factor to carry out regulating and controlling test, magnetic proton is cylindrical, basal diameter 4 centimetres, thickness 1.875 centimetres, and density is 7 grams every cubic centimetre, and volume is 23.55 cubic centimetres.Soft material adopts silica gel thin film, and density is 1.3 grams every cubic centimetre, and thickness is also 1.875 centimetres, and hard material adopts aluminium, and density is 2.7 grams every cubic centimetre.We utilize hot-wire coil to produce the magnetic field of different gradient magnitude, and act on above sample, utilize test macro to obtain sound insulation room discharge curve, as shown in Figure 4.As can be seen from the figure, externally-applied magnetic field can regulate and control the size of oise insulation factor crest frequency really, sound insulation room discharge curve figure when solid straight line represents that the equivalent force that externally-applied magnetic field produces on proton is 0N, sound insulation room discharge curve figure when dotted line represents that the equivalent force that externally-applied magnetic field produces on proton is 1.1775mN, sound insulation room discharge curve figure when the horizontal dotted line of point represents that the equivalent force that externally-applied magnetic field produces on proton is 4.170mN, sound insulation room discharge curve figure when thin number line represents that the equivalent force that externally-applied magnetic field produces on proton is 8.340mN.More each bar curve can obtain, and when the gradient of externally-applied magnetic field is larger time, the crest frequency of oise insulation factor moves also larger.Corresponding vibration can be evoked when disturbing sound wave incident outward to during this present invention surface, resonance peak and antiresonance peak can be found by spectrum analysis, near the position at antiresonance peak, being the good frequency range of defening effect.External magnetic field can control the stressing conditions of magnetic material in this structural unit and soft material, thus the position at mobile antiresonance peak.Within the scope of elastic properties of materials, added magnetic field is larger, the movement of oise insulation factor peak value is just larger, so can according to the frequency distribution of outside noise and situation of change, by regulation and control externally-applied magnetic field size, isolates sound amount peak value is moved to and outside noise frequency anastomosis, realizes extraordinary active defening effect.
The above, be only the preferred embodiments of the present invention, when not limiting scope of the invention process with this, the simple equivalence namely generally done according to the claims in the present invention and description of the invention content changes and modifies, and all should still belong in the scope of patent of the present invention covering.

Claims (8)

1. a controllable magnetic field sound insulation room structure, it is characterized in that, comprise: the matrix (1) that all round closure and middle part have through hole, the flexible material (2) being embedded in the magnetic proton (3) in the through hole of this matrix and being attached between described matrix and magnetic proton (3) gap, this flexible material (2) is fixedly connected with described matrix, magnetic proton respectively.
2. controllable magnetic field sound insulation room structure according to claim 1, is characterized in that, described matrix (1) is that the hard material being greater than 1Gpa by Young modulus is made.
3. controllable magnetic field sound insulation room structure according to claim 1, is characterized in that, described flexible material layer (2) is that the flexible material being less than 1Gpa by Young modulus is made.
4. controllable magnetic field sound insulation room structure according to claim 3, is characterized in that, described flexible material is silicon rubber or styrene-butadiene rubber.
5. controllable magnetic field sound insulation room structure according to claim 1, is characterized in that, described magnetic proton (3) is made up of hard magnetic material or soft magnetic material.
6. controllable magnetic field sound insulation room structure according to claim 1, is characterized in that, the consistency of thickness of described matrix (1) and flexible material layer (2), and between 1mm-10mm.
7. controllable magnetic field sound insulation room structure according to claim 6, is characterized in that, the radius of described magnetic proton is no more than 10mm.
8. a controllable magnetic field low-frequency sound insulating material, is characterized in that, is rearranged by the controllable magnetic field sound insulation room structural periodicity described in one or more any one of claim 1-7.
CN201510070456.XA 2015-02-11 2015-02-11 Magnetic-field-adjustable low-frequency sound insulation structure and sound insulation material Pending CN104681021A (en)

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106678271A (en) * 2016-12-08 2017-05-17 西北工业大学 Local resonance low-frequency band gap vibration suppression periodic structure
CN107274880A (en) * 2017-07-04 2017-10-20 北京市劳动保护科学研究所 A kind of non-linear magnetic force negative stiffness Active Absorption device
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
CN109493840A (en) * 2018-12-06 2019-03-19 南京航空航天大学 Adjustable double-layer thin web acoustic metamaterial structure based on the effect of permanent magnet repulsion
CN109505904A (en) * 2018-12-27 2019-03-22 长沙理工大学 A kind of low frequency vibration damping Meta Materials
CN110501419A (en) * 2019-07-18 2019-11-26 江苏大学 A kind of acoustic measurement system of the axially adjustable uniform magnetic field loading device of band
CN111907433A (en) * 2020-07-15 2020-11-10 南京林业大学 Magneto-rheological fluid unit based sound insulation method with good low-frequency sound insulation quantity adjusting performance
CN112259066A (en) * 2020-10-23 2021-01-22 西安交通大学 N-order acoustic metamaterial low-frequency sound insulation structure
CN112878219A (en) * 2021-01-14 2021-06-01 西南大学 Phononic crystal sound barrier with self-adaptive function

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US5709053A (en) * 1994-05-23 1998-01-20 Zeon Kasei Co., Ltd Panel for constituting sound insulating wall
CN202345901U (en) * 2011-07-21 2012-07-25 昆明理工大学 Composite-material-based noise elimination tile
DE202012100466U1 (en) * 2012-02-10 2013-05-13 Odenwald-Chemie Gmbh Sound Absorber
WO2015000122A1 (en) * 2013-07-02 2015-01-08 Dou Jielong Energy-saving airtight steam conduction type food cooking device

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US5236186A (en) * 1991-11-22 1993-08-17 Firma Carl Freudenberg Vibration damper
US5709053A (en) * 1994-05-23 1998-01-20 Zeon Kasei Co., Ltd Panel for constituting sound insulating wall
CN202345901U (en) * 2011-07-21 2012-07-25 昆明理工大学 Composite-material-based noise elimination tile
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106678271A (en) * 2016-12-08 2017-05-17 西北工业大学 Local resonance low-frequency band gap vibration suppression periodic structure
CN107274880A (en) * 2017-07-04 2017-10-20 北京市劳动保护科学研究所 A kind of non-linear magnetic force negative stiffness Active Absorption device
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
CN108447467B (en) * 2018-03-30 2022-04-12 北京速阔智能科技有限公司 Active acoustic metamaterial structure unit and control device thereof
CN109493840A (en) * 2018-12-06 2019-03-19 南京航空航天大学 Adjustable double-layer thin web acoustic metamaterial structure based on the effect of permanent magnet repulsion
CN109505904A (en) * 2018-12-27 2019-03-22 长沙理工大学 A kind of low frequency vibration damping Meta Materials
CN110501419A (en) * 2019-07-18 2019-11-26 江苏大学 A kind of acoustic measurement system of the axially adjustable uniform magnetic field loading device of band
CN111907433A (en) * 2020-07-15 2020-11-10 南京林业大学 Magneto-rheological fluid unit based sound insulation method with good low-frequency sound insulation quantity adjusting performance
CN112259066A (en) * 2020-10-23 2021-01-22 西安交通大学 N-order acoustic metamaterial low-frequency sound insulation structure
CN112878219A (en) * 2021-01-14 2021-06-01 西南大学 Phononic crystal sound barrier with self-adaptive function

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Application publication date: 20150603