CN108417197A - A kind of super clever surface apparatus of acoustics based on helmholtz resonance chamber - Google Patents
A kind of super clever surface apparatus of acoustics based on helmholtz resonance chamber Download PDFInfo
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- CN108417197A CN108417197A CN201810165514.0A CN201810165514A CN108417197A CN 108417197 A CN108417197 A CN 108417197A CN 201810165514 A CN201810165514 A CN 201810165514A CN 108417197 A CN108417197 A CN 108417197A
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- super clever
- clever surface
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- mount board
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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
- G10K11/36—Devices for manipulating acoustic surface waves
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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
- G10K11/18—Methods or devices for transmitting, conducting or directing sound
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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 invention discloses a kind of super clever surface apparatus of acoustics based on helmholtz resonance chamber, super clever surface mount board, super clever surface cell including arrangement symmetrical above and below and supporting rack, crack is formed between upper and lower super clever surface cell, super clever surface cell is connected across crack position with the super clever surface mount board of arrangement symmetrical above and below, super clever surface mount board is connected with supporting rack, and supporting rack is used to support super clever surface mount board.The super clever surface apparatus of a kind of acoustics based on helmholtz resonance chamber provided by the present invention, it is simple in structure, it is convenient to mount and dismount, super clever surface cell can move, stronger compared to folding super clever surface flexibility and adjustability.
Description
Technical field
The invention belongs to the acoustical device technical fields of sound wave wave surface control, and in particular to a kind of total based on Helmholtz
Shake the super clever surface apparatus of acoustics of chamber.
Background technology
Sound wave is a kind of mechanical wave, is usually expressed as longitudinal wave, and it is the transmission of energy in the medium to propagate essence.With section
The progress of skill, acoustics are explored under water, subsurface investigation, and biomedical, the fields such as military weapon are obtained for important application.
The metamaterial and super clever surface occurred in recent years has property not available for natural material, such as negative refraction
Deng they produce significant impact to electromagnetic wave field, it is contemplated that sound wave is similar with electromagnetism wave property, by super clever surface introducing sound
The problems such as field manipulates for sound wave wave surface provides new solution.The super clever surface of acoustics more at present uses space
Folding structure, although they can realize that wave surface manipulates, complicated, transmission efficiency is low, and transmission band is narrow.
By broad sense Snell's law it is found that the phase gradient of control sound wave can control refraction angle.Helmholtz resonance chamber
It is a kind of typical acoustic element, it is simple in structure, control sound using the variation of helmholtz resonance chamber effective bulk modulus
Wave phase gradient is a kind of simple and practicable method.
Invention content
Present invention aim to address the above problems, and providing one kind having higher transmission efficiency, can be to being taken the photograph along its normal direction
The plane wave entered carries out the super clever surface apparatus of the acoustics based on helmholtz resonance chamber of arbitrary wave surface manipulation.
In order to solve the above technical problems, the technical scheme is that：A kind of acoustics based on helmholtz resonance chamber is super
Clever surface apparatus, including the super clever surface mount board of arrangement symmetrical above and below, super clever surface cell and supporting rack, upper and lower super clever surface
Crack is formed between unit, super clever surface cell is connected across crack position with the super clever surface mount board of arrangement symmetrical above and below, surpasses
Clever surface mount board is connected with supporting rack, and supporting rack is used to support super clever surface mount board.
Preferably, the cross section of the super clever surface mount board is arch disk-like structure, and super clever surface mount board is equipped with
Groove, super clever surface cell are connected by groove with super clever surface mount board；Super clever surface mount board be equipped with arch column chamber and
Mounting hole, arch column intracavitary portion are filled with silencing cotton, and super clever surface mount board is connected by mounting hole with plane wave duct.
Preferably, the super clever surface cell includes super clever surface substrate, super clever surface cap and super clever surface fastener,
Super clever surface substrate concave surface forms groove, and super clever surface cap is positioned in the groove of super clever surface substrate；Super clever surface
The groove of substrate is equipped with cylindrical cavity counterbore, and super clever surface cap is equipped with super clever surface cap pore, and super clever surface cap is thin
Hole is corresponding with cylindrical cavity counterbore；Super clever surface substrate and super clever surface cap are fixed and are connected by screw by super clever surface fastener
It connects.
Preferably, the quantity of the cylindrical cavity counterbore is four, and cylindrical cavity counterbore is linearly arranged in super clever surface substrate
In groove.
Preferably, super clever surface fixture block is connected on support frame as described above, super clever surface fixture block is logical with super clever surface mount board
Screw is crossed to be connected.
Preferably, the super clever surface cell is connected with super clever surface mount board by the pinching screw arranged up and down, folder
Tight screw is for adjusting position of the super clever surface cell among super clever surface mount board.
Preferably, silencing cotton is installed in the crack.
The beneficial effects of the invention are as follows：
1, the super clever surface apparatus of a kind of acoustics based on helmholtz resonance chamber provided by the present invention, simple in structure, dress
It tears open conveniently, super clever surface cell can move, stronger compared to folding super clever surface flexibility and adjustability.
2, the present invention is not only to utilize resonant frequency, and transmission band is wider than folding super clever surface, is had higher
Efficiency of transmission.
3, the adjustability of super clever surface cell has fully expanded the function on super clever surface, as long as the super clever surface cell of change
Single slit width degree can realize different phase gradient distributions, to realize the sound wave manipulation at different refraction angles.The sound that can be realized
The manipulation of wave wave surface has plane wave anomalous refraction, salt free ligands Bezier wave beam, sound wave convergence etc..
4, super clever surface and the combination of other devices are flexible, have flange arrangement and bolt hole on super clever surface mount board,
Can with plane wave duct, sensing detection module connection, constitute complete experimental facilities be used for probe into frequency, the impedance on super clever surface with
And more characteristics.
Description of the drawings
Fig. 1 is a kind of structural schematic diagram of the super clever surface apparatus of acoustics based on helmholtz resonance chamber of the invention；
Fig. 2 is the structural schematic diagram of the super clever surface mount board of the present invention；
Fig. 3 is sectional views of the Fig. 2 of the present invention on the directions A-A；
Fig. 4 is the half section structure diagram of Fig. 1 of the present invention；
Fig. 5 is sectional views of the Fig. 4 of the present invention on the directions B-B；
Fig. 6 is the schematic diagram that the present invention carries out sound wave convergence.
Reference sign：20, super clever surface mount board；21, super clever surface cell；22, supporting rack；23, arch column chamber；
24, mounting hole；25, super clever surface substrate；26, super clever surface cap；27, super clever surface fastener；28, cylindrical cavity counterbore；29、
Super clever surface cap pore；201, super clever surface fixture block；202, fishbolt；203, silencing cotton.
Specific implementation mode
The present invention is described further in the following with reference to the drawings and specific embodiments：
As shown in Fig. 1 to Fig. 6, the super clever surface apparatus of a kind of acoustics based on helmholtz resonance chamber provided by the invention,
Super clever surface mount board 20, super clever surface cell 21 including arrangement symmetrical above and below and supporting rack 22, upper and lower super clever surface cell
Crack is formed between 21, and silencing cotton 203 is installed in crack.Super clever surface cell 21 passes through crack position and arrangement symmetrical above and below
Super clever surface mount board 20 is connected, and super clever surface mount board 20 is connected with supporting rack 22, and supporting rack 22 is used to support super clever surface
Mounting plate 20.
The cross section of super clever surface mount board 20 is arch disk-like structure, and super clever surface mount board 20 is equipped with groove, surpasses
Clever surface cell 21 is connected by groove with super clever surface mount board 20；Super clever surface mount board 20 is equipped with 23 He of arch column chamber
Mounting hole 24,23 inside of arch column chamber are filled with silencing cotton 203, and super clever surface mount board 20 passes through mounting hole 24 and plane wave duct
It is connected.
Super clever surface mount board 20 can flexibly be combined by mounting hole 24 with other devices, can be with plane wave
Pipe, the connection of sensing detection module constitute frequency, impedance and more spies that complete experimental facilities is used for probing into super clever surface
Property.
Super clever surface cell 21 includes super clever surface substrate 25, super clever surface cap 26 and super clever surface fastener 27, is surpassed
25 concave surface of clever surface substrate forms groove, and super clever surface cap 26 is positioned in the groove of super clever surface substrate 25；It is super clever
The groove of surface substrate 25 is equipped with cylindrical cavity counterbore 28, and super clever surface cap 26 is equipped with super clever surface cap pore 29, surpasses
Clever surface cap pore 29 is corresponding with cylindrical cavity counterbore 28；Super clever surface fastener 27 is by screw by super 25 He of clever surface substrate
Super clever surface cap 26 is fixedly connected.The quantity of cylindrical cavity counterbore 28 is four, and cylindrical cavity counterbore 28 is linearly arranged in super clever table
In the groove of face substrate 25.
In the present embodiment, what multiple super clever surface cells 21 were spaced is arranged between super clever surface mount board 20.It is adjacent
Gap between super clever surface cell 21 is single seam, and single slit width degree by changing adjacent super clever surface cell 21 can be realized not
Same phase gradient distribution, to realize the sound wave manipulation at different refraction angles, moreover it is possible to which the sound wave wave surface manipulation of realization has flat
Surface wave anomalous refraction, salt free ligands Bezier wave beam, sound wave convergence etc..
Super clever surface cell 21 is connected with super clever surface mount board 20 by the fishbolt 202 arranged up and down, and spiral shell is clamped
Bolt 202 is used to adjust position of the super clever surface cell 21 among super clever surface mount board 20.It in the present embodiment, can be according to setting
Meter needs that position of the super clever surface cell 21 among super clever surface mount board 20 is adjusted, to reach best use effect
Fruit and requirement.
Super clever surface fixture block 201 is connected on supporting rack 22, super clever surface fixture block 201 passes through with super clever surface mount board 20
Screw is connected.
Working process and principle of the invention are：
Frequency of sound wave is determined first and wants the sound wave realized and manipulates form, so that it is determined that super clever surface cell 21 is put
Seated position, detailed process are as follows：
Present invention employs the anomalous refractions that helmholtz resonance chamber (Helmholtz resonator, HR) realizes sound wave.
The super clever surface cell 21 that Fig. 4 is shown is made of the HR of array, and dimensional structure is shown in Fig. 5.The equivalent volume modulus of the unit
It is represented by：
In formula,It is the bulk modulus of air, F=ab/Ld is the area ratio of HR cavitys and single seam part, ω0It is
The resonant frequency of HR, Γ are the intrinsic losses of HR.Equation (1) indicates that the unit 21 on super clever surface has 2 characteristic frequenciesWithWhereinIt is the acoustic capacitance for characterizing HR cavity spring effects, MHR=
ρ0heff/ l is and the acoustic mass corresponding to the air quality in HR throats, heffIt is the effective length of throat.In ω0＜ ω ＜
ωnFrequency range in, the real part of effective bulk modulus is negative value.According to Acoustic Wave-equation and Newton's law it is found that HR
In the presence of not interfering with effective mass.Therefore, effective sound velocity can be expressed asThe wave of super clever surface cell 21
Vector can be expressed asIn ω0＜ ω ＜ ωnFrequency range in, wave vector is imaginary number, and sound wave is in the directions x
Rapid decaying, cannot pass through super clever surface.In other frequency ranges such as ω ＜ ω0, ω ＞ ωn, wave vector is real number, sound wave energy
Super clever surface is passed through well.Ignore intrinsic loss, the inverse of the effective sound velocity in super clever surface cell 21 can be write as：
Equation (2) is pointed out：(i) as frequency is from ω00 is decayed to, effective sound velocity increases to from 0The value
Less than the velocity of sound c in air0.(ii) in ω ＞ ωnFrequency range in, with the increase of frequency, effective sound velocity subtracts from infinity
Less to 0.(iii) velocity of sound is influenced by the area ratio F of HR cavitys and single seam part.For being less than ω0Frequency, effective sound velocity value with
F is inversely proportional.Single slit width degree is suitably chosen, the value of F can also change simultaneously, and there are inverse relations between d and F.Therefore, when
Frequencies omega ＜ ω0When, by changing single slit width degree, we can be easily obtained ideal sound velocity gradient.
Sound wave passes through after super clever surface, it may appear that acoustic phase non-continuous event.Usually, arbitrary wave surface operates all
It can be instructed by broad sense Snell's law.Transmission sound wave across the super clever surface of acoustics can write following formula：
In formula, θt(y), θi(y) it is respectively refraction angle and incidence angle.Φ (y) is phase factor, k0=ω/c0For in air
Wave vector.It was found that the gradient by changing phase factor, incident acoustic wave can be reflected arbitrarily.When there are one at me
Plane wave in interested frequency range along super clever surface normal incidence (i.e. θi(y)=0), single by choosing super clever surface
Single slit width degree of member 21, can obtain gradient distribution slows down the velocity of sound.Phase gradient can be writeWherein c (y) is the speed along the super directions clever surface y.Bring phase gradient into equation
(3), refraction angle can write：
Equation (4) shows that refraction angle is directly determined by the gradient of 1/c (y).Therefore, by adjusting speed inverse gradient terms,
The manipulation of arbitrary wave surface may be implemented, i.e.,：
By taking sound wave converges as an example, calculating the required single slit width degree of realization sound wave wave surface manipulation, steps are as follows.Fig. 6 is illustrated
Sound wave converges concept principle figure, and incident plane wave is converged to focus (x by designed super clever surface energy0, 0) on, refraction angle
Sine value can write：
Then equation can be written as along the distribution of the speed inverse in the directions y：
X in formula0For the abscissa of focus, there is minimum speed c (0)=c in super clever surface midpointmin(0).In super clever table
There is maximum speed in face edgeBring speed inverse into equation (2), you can counter to solve single slit width degree d.
After the single slit width degree for solving excess of export grain husk surface cell 21, super clever surface cell is accurately placed with vernier caliper
21, it is used in combination fishbolt 202 to fix its position, is installed with super clever surface in the half moon groove of super clever surface mount board 20
Place silencing cotton 23 in groove both sides on plate 20, it is ensured that sound wave can only be transferred to environment from super clever surface, and will not be in super clever table
It is reflected on the mounting plate of face, influences super clever surface effect.
Those of ordinary skill in the art will understand that the embodiments described herein, which is to help reader, understands this hair
Bright principle, it should be understood that protection scope of the present invention is not limited to such specific embodiments and embodiments.This field
Those of ordinary skill can make according to the technical disclosures disclosed by the invention various does not depart from the other each of essence of the invention
The specific variations and combinations of kind, these variations and combinations are still within the scope of the present invention.
Claims (7)
1. a kind of super clever surface apparatus of acoustics based on helmholtz resonance chamber, it is characterised in that：Including arrangement symmetrical above and below
Super clever surface mount board (20), super clever surface cell (21) and supporting rack (22) are formed between super clever surface cell (21) up and down
Crack, super clever surface cell (21) are connected across crack position with the super clever surface mount board (20) of arrangement symmetrical above and below, super clever table
Face mounting plate (20) is connected with supporting rack (22), and supporting rack (22) is used to support super clever surface mount board (20).
2. the super clever surface apparatus of a kind of acoustics based on helmholtz resonance chamber according to claim 1, it is characterised in that：
The cross section of the super clever surface mount board (20) is arch disk-like structure, and super clever surface mount board (20) is equipped with groove, surpasses
Clever surface cell (21) is connected by groove with super clever surface mount board (20)；Super clever surface mount board (20) is equipped with arch column
Chamber (23) and mounting hole (24), arch column chamber (23) is internal to be filled with silencing cotton (203), and super clever surface mount board (20) passes through peace
Dress hole (24) is connected with plane wave duct.
3. the super clever surface apparatus of a kind of acoustics based on helmholtz resonance chamber according to claim 1, it is characterised in that：
The super clever surface cell (21) includes super clever surface substrate (25), super clever surface cap (26) and super clever surface fastener
(27), super clever surface substrate (25) concave surface forms groove, and super clever surface cap (26) is positioned over super clever surface substrate (25)
Groove in；The groove of super clever surface substrate (25) is equipped with cylindrical cavity counterbore (28), and super clever surface cap (26) is equipped with super
Clever surface cap pore (29), super clever surface cap pore (29) are corresponding with cylindrical cavity counterbore (28)；Super clever surface fastener
(27) super clever surface substrate (25) is fixedly connected with super clever surface cap (26) by screw.
4. the super clever surface apparatus of a kind of acoustics based on helmholtz resonance chamber according to claim 3, it is characterised in that：
The quantity of the cylindrical cavity counterbore (28) is four, and cylindrical cavity counterbore (28) is linearly arranged in the groove of super clever surface substrate (25)
In.
5. the super clever surface apparatus of a kind of acoustics based on helmholtz resonance chamber according to claim 1, it is characterised in that：
Super clever surface fixture block (201), super clever surface fixture block (201) and super clever surface mount board (20) are connected on support frame as described above (22)
It is connected by screw.
6. the super clever surface apparatus of a kind of acoustics based on helmholtz resonance chamber according to claim 2, it is characterised in that：
The super clever surface cell (21) is connected with super clever surface mount board (20) by the fishbolt (202) arranged up and down, is clamped
Bolt (202) is used to adjust super clever surface cell (21) position intermediate in super clever surface mount board (20).
7. the super clever surface apparatus of a kind of acoustics based on helmholtz resonance chamber according to claim 1, it is characterised in that：
Silencing cotton (203) is installed in the crack.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810165514.0A CN108417197A (en) | 2018-02-28 | 2018-02-28 | A kind of super clever surface apparatus of acoustics based on helmholtz resonance chamber |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810165514.0A CN108417197A (en) | 2018-02-28 | 2018-02-28 | A kind of super clever surface apparatus of acoustics based on helmholtz resonance chamber |
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| CN201810165514.0A Pending CN108417197A (en) | 2018-02-28 | 2018-02-28 | A kind of super clever surface apparatus of acoustics based on helmholtz resonance chamber |
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Cited By (3)
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| CN110012397A (en) * | 2019-05-10 | 2019-07-12 | 美特科技(苏州)有限公司 | A kind of loudspeaker |
| CN111739499A (en) * | 2020-06-01 | 2020-10-02 | 南京航空航天大学 | Underwater Helmholtz resonance cavity with rough inner insertion pipe |
| CN113314090A (en) * | 2021-02-26 | 2021-08-27 | 西南交通大学 | Controllable acoustic super surface for generating acoustic track angular momentum |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110012397A (en) * | 2019-05-10 | 2019-07-12 | 美特科技(苏州)有限公司 | A kind of loudspeaker |
| CN111739499A (en) * | 2020-06-01 | 2020-10-02 | 南京航空航天大学 | Underwater Helmholtz resonance cavity with rough inner insertion pipe |
| CN111739499B (en) * | 2020-06-01 | 2023-09-29 | 南京航空航天大学 | Coarse interpolation type underwater Helmholtz resonance cavity |
| CN113314090A (en) * | 2021-02-26 | 2021-08-27 | 西南交通大学 | Controllable acoustic super surface for generating acoustic track angular momentum |
| CN113314090B (en) * | 2021-02-26 | 2022-10-18 | 西南交通大学 | Controllable acoustic super surface for generating acoustic track angular momentum |
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