CN106205597B - Realize that underwater sound wave orients stealthy phonon functional structure and production method - Google Patents
Realize that underwater sound wave orients stealthy phonon functional structure and production method Download PDFInfo
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- CN106205597B CN106205597B CN201610536880.3A CN201610536880A CN106205597B CN 106205597 B CN106205597 B CN 106205597B CN 201610536880 A CN201610536880 A CN 201610536880A CN 106205597 B CN106205597 B CN 106205597B
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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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- 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
- G10K11/20—Reflecting arrangements
- G10K11/205—Reflecting arrangements for underwater use
Abstract
Realize that underwater sound wave orients stealthy phonon functional structure and production method the embodiment of the invention provides a kind of.The realization underwater sound wave orients stealthy phonon functional structure, comprising: alloy matrix aluminum；The hole arranged according to plane positive triangle lattice period is drilled on the alloy matrix aluminum.The centre of the alloy matrix aluminum is provided with the cavity through the alloy matrix aluminum, for placing target to be concealed.Structure of the invention need to only drill on alloy matrix aluminum and obtain, and the processing is simple.
Description
Technical field
The present invention relates to field of acoustics more particularly to a kind of realize that underwater sound wave orients stealthy phonon functional structure and system
Make method.
Background technique
Optics and Acoustics Stealth Technology can make object hide the detection of electromagnetic wave or sound wave.2006, empire, Britain reason
Professor J.B.Pendry of engineering college has been put forward for the first time the stealthy cover arrangement method based on optical transform, corresponding result of study hair
Table has led the research boom to Meta Materials on " science " magazine.Meta Materials have certain not available for natural material
A little characteristics, such as so that wave " is bypassed " material surface and realize that stealthy acoustics, optic camouflage and electromagnetic wave are stealthy.Stealthy key is
Design, including designing the microstructure unit of certain sub-wavelength rank and the queueing discipline of these units, and finally determines its object
It manages characteristic (such as dielectric constant, magnetic conductivity, bulk modulus and mass density).
Sound stealth is just to start to cause the concern of people nearly ten years and starting to be studied.This is mainly by current
Active/passive sonar mainly used to the undersea detection of submarine, but when passive sonar positions target, to generate ranging information inaccurate
The problem of.In addition, advanced submarine Sound stealth performance greatly improves, so that the Effect on Detecting of passive sonar declines.Therefore, master is utilized
Dynamic radiocoustic position finding becomes detection submarine and implements the important means of precision strike.Although Meta Materials are stealthy to be had in terms of theoretical research
Very fast progress, but a bottleneck is that the performance of material is severely limited by absorption loss water.Acoustics cape designs acoustic construction simultaneously
Extremely harsh with processing request, progress is slower in terms of experimental verification.Therefore it is next real to propose many other methods by scientific research personnel
Now sound wave is stealthy, such as utilizes photonic crystal structure.
Phonon crystal (artificial cycle structure) is the artificial period elastic fluid structure with phonon-side bands.Existed using sound wave
Regulation of the constituent element and its structure of propagation law and different materials in different cycles structural material to band structure and band gap
Mechanism can be modulated in the form of to sound field by design optimization phonon crystal, to control the propagation and distribution of sound wave.By setting
The change of gradient of refractive index may be implemented in the phonon crystal of meter structure gradient distribution, so that sound wave be made to get around stealthy regional spread simultaneously
Sound stealth is realized in a particular direction.
Summary of the invention
Realize that underwater sound wave orients stealthy phonon functional structure and production method the embodiment provides a kind of,
The processing is simple.
To achieve the goals above, this invention takes following technical solutions.
It is a kind of to realize that underwater sound wave orients stealthy phonon functional structure, comprising:
Alloy matrix aluminum；
The through hole arranged according to plane positive triangle lattice period is drilled on the alloy matrix aluminum, the through hole is along Z
Axis direction runs through the alloy matrix aluminum.
The centre of the alloy matrix aluminum is provided with the cavity for running through the alloy matrix aluminum along Z-direction, for placing
Target to be concealed.
The diameter of the cavity is less than or equal to the half of the width of the alloy matrix aluminum along the y-axis direction.
The through hole includes: regular hexagon hole；
Each side of the regular hexagon hole is connected with T-shaped hole.
The alloy matrix aluminum is symmetrical along the x axis；
Distribution gradient, the refractive index of the regular hexagon hole are terraced along the y axis for the size of the regular hexagon hole
Degree is distributed along the y axis for hyperbolic secant；
The regular hexagon hole is in distribution in the same size along the x axis, and the refractive index of the regular hexagon hole is along X-axis
Direction is uniformly distributed.
When stealthy frequency is 25kHz, the density of the alloy matrix aluminum is ρ=2.7g/cm3；The alloy matrix aluminum
Longitudinal wave velocity and transverse wave speed be respectively cl=6.15km/s and ct=3.1km/s；
The lattice constant a=20mm of the regular hexagon hole；The length L=of the alloy matrix aluminum in the X-axis direction
24a；
The size of the T-shaped hole is respectively as follows: the boundary of unit cell of the cross-drilled hole of T-shaped hole to the alloy matrix aluminum
Distance b=0.0275a, the length e=0.32a of the cross-drilled hole of T-shaped hole, the width h=0.06a of the cross-drilled hole of T-shaped hole
With the width t=0.05a of the vertical core of T-shaped hole；
The aperture d of the regular hexagon hole is followed successively by 0.5a, 0.507a, 0.526a, 0.556a along the size of y-axis,
0.594a,0.636a,0.68a。。
The alloy matrix aluminum Z-direction with a thickness of the lattice constant at least ten times.
A kind of production method realized underwater sound wave and orient stealthy phonon functional structure characterized by comprising
Select an alloy matrix aluminum；
The through hole arranged according to plane positive triangle lattice period, the through hole are cut on the alloy matrix aluminum
Run through the alloy matrix aluminum along Z-direction.
The production method of the phonon functional structure, further includes:
It is cut into the cavity through the alloy matrix aluminum in the centre of the alloy matrix aluminum, for placing mesh to be concealed
Mark.
The production method of the phonon functional structure, further includes:
At least two alloy matrix aluminum bondings of the through hole will be cut into, so that the aluminium alloy after bonding
Matrix z-axis direction with a thickness of lattice constant at least ten times.
As can be seen from the technical scheme provided by the above-mentioned embodiment of the present invention, the structure of the embodiment of the present invention only need to be in aluminium
Drilling obtains on alloy substrate, and the processing is simple.
The additional aspect of the present invention and advantage will be set forth in part in the description, these will become from the following description
Obviously, or practice through the invention is recognized.
Detailed description of the invention
In order to illustrate the technical solution of the embodiments of the present invention more clearly, required use in being described below to embodiment
Attached drawing be briefly described, it should be apparent that, drawings in the following description are only some embodiments of the invention, for this
For the those of ordinary skill of field, without any creative labor, it can also be obtained according to these attached drawings other
Attached drawing.
Fig. 1 is a kind of vertical view realized underwater sound wave and orient stealthy phonon functional structure provided in an embodiment of the present invention
Figure；
Fig. 2 is provided in an embodiment of the present invention a kind of to realize that underwater sound wave orients the solid of stealthy phonon functional structure and shows
It is intended to；
Fig. 3 is to realize that underwater sound wave orients the schematic diagram of the unit cell of stealthy phonon functional structure in Fig. 1；
Fig. 4 is a kind of stealthy effect realized underwater sound wave and orient stealthy phonon functional structure provided in an embodiment of the present invention
Fruit simulation drawing；
Fig. 5 is a kind of production side for realizing underwater sound wave and orienting stealthy phonon functional structure provided in an embodiment of the present invention
The flow chart of method.
Specific embodiment
Embodiments of the present invention are described below in detail, the example of the embodiment is shown in the accompanying drawings, wherein from beginning
Same or similar element or element with the same or similar functions are indicated to same or similar label eventually.Below by ginseng
The embodiment for examining attached drawing description is exemplary, and for explaining only the invention, and is not construed as limiting the claims.
Fig. 1 is a kind of vertical view realized underwater sound wave and orient stealthy phonon functional structure provided in an embodiment of the present invention
Figure；Fig. 2 is a kind of stereoscopic schematic diagram realized underwater sound wave and orient stealthy phonon functional structure provided in an embodiment of the present invention；
Fig. 3 is to realize that underwater sound wave orients the schematic diagram of the unit cell of stealthy phonon functional structure in Fig. 1；Fig. 4 is the embodiment of the present invention
A kind of stealth effect simulation drawing realized underwater sound wave and orient stealthy phonon functional structure provided；Below in conjunction with Fig. 1-Fig. 4
Description.
It is described a kind of to realize that underwater sound wave orients stealthy phonon functional structure, comprising:
Alloy matrix aluminum 11；
The through hole arranged according to plane positive triangle lattice period, the through hole edge are drilled on the alloy matrix aluminum 11
Z-direction runs through the alloy matrix aluminum.
The centre of the alloy matrix aluminum 11 is provided with the cavity 12 for running through the alloy matrix aluminum along Z-direction, is used for
Place target to be concealed.
The diameter of the cavity is less than or equal to the half of the width of the alloy matrix aluminum along the y-axis direction.
The through hole includes: regular hexagon hole 13；
Each side of the regular hexagon hole 13 is connected with T-shaped hole 14.
The alloy matrix aluminum is symmetrical along the x axis；
Distribution gradient, the refractive index of the regular hexagon hole are terraced along the y axis for the size of the regular hexagon hole
Degree is distributed along the y axis for hyperbolic secant；
The regular hexagon hole is in distribution in the same size along the x axis, and the refractive index of the regular hexagon hole is along X-axis
Direction is uniformly distributed.
When stealthy frequency is 25kHz, the density of the alloy matrix aluminum is ρ=2.7g/cm3；The alloy matrix aluminum
Longitudinal wave velocity and transverse wave speed be respectively cl=6.15km/s and ct=3.1km/s；
The lattice constant a=20mm of the regular hexagon hole；The length L=of the alloy matrix aluminum in the X-axis direction
24a；
The size of the T-shaped hole is respectively as follows: the boundary of unit cell of the cross-drilled hole of T-shaped hole to the alloy matrix aluminum
Distance b=0.0275a, the length e=0.32a of the cross-drilled hole of T-shaped hole, the width h=0.06a of the cross-drilled hole of T-shaped hole
With the width t=0.05a of the vertical core of T-shaped hole；
The aperture d of the regular hexagon hole is followed successively by 0.5a, 0.507a, 0.526a, 0.556a along the size of y-axis,
0.594a,0.636a,0.68a。
The stealthy frequency and the size of the lattice constant a are changed in equal proportion；
The cross-drilled hole of T-shaped hole is to the distance b on boundary of unit cell of the alloy matrix aluminum, the cross-drilled hole of T-shaped hole
Width h, T-shaped hole vertical core width t reduction so that stealthy frequency reduce, the length e's of the cross-drilled hole of T-shaped hole subtracts
It is small to increase stealthy frequency.
The alloy matrix aluminum Z-direction with a thickness of the lattice constant at least ten times.
Embodiment is described below.
A kind of underwater sound wave that may be implemented orients stealthy phonon functional structure, by refractive index distribution gradient and is drilled with week
The aluminum alloy materials of phase through hole are made.This periodic structure is triangular shaped periods arrangement, and there are six symmetry axis；Equal frequency curves
It shows close to isotropic feature；
The present invention is to drill out the through hole of gradient distribution on aluminum substrate and arrange according to triangular crystal lattice.Through hole is
It is collectively constituted by the T-shaped hole of connection on regular hexagon hole and each side；
The size distribution gradient of regular hexagon hole, and its corresponding refractive index also distribution gradient；Specifically: refraction
Rate gradient is controlled by the size of regular hexagon hole；Refractive index gradient is hyperbolic secant distribution along y-axis, is uniformly to divide along x-axis
Cloth.
The impedance match of structure and water is high, can be realized high-transmission rate.
Specifically: in phonon functional material band structure figure, abscissa is wave vector, and ordinate is frequency.It is hidden determining
After frequency needed for body (frequency needs are chosen on the Article 4 band of band structure), wave vector corresponding to this frequency is also determined
?.When the variation of regular hexagon aperture, wave vector corresponding to this frequency can also change.When the size of wave vector is in double along y-axis
When bent secant is distributed, refractive index gradient is also in hyperbolic secant distribution.The relational expression of refractive index and y-coordinate are as follows: n (y)=n0sech
(δy)(n0Refractive index when for y=0).Wherein, the gradient index δ of hyperbolic secant distribution is by the length L of porous plate (along x-axis side
To) determine, relational expression are as follows: δ=π/L.
As shown in figure 5, being a kind of production realized underwater sound wave and orient stealthy phonon functional structure of the present invention
Method, comprising:
Step 210, an alloy matrix aluminum is selected；
Step 220, the through hole arranged according to plane positive triangle lattice period, institute are cut on the alloy matrix aluminum
Through hole is stated along Z-direction through the alloy matrix aluminum.
The production method of the phonon functional structure, further includes:
Step 230, it is cut into the cavity through the alloy matrix aluminum in the centre of the alloy matrix aluminum, for placing
Target to be concealed.
The production method of the phonon functional structure, further includes:
Step 240, at least two alloy matrix aluminums for being cut into the through hole are bonded, so that the institute after bonding
State alloy matrix aluminum z-axis direction with a thickness of lattice constant at least ten times.
Embodiment is described below.
A kind of production method that underwater sound wave may be implemented and orients stealthy phonon functional structure, comprising the following steps:
Step 1: the aluminium alloy plate of selection suitable material parameter and thickness；The aluminium alloy density as selected by present case be ρ=
2.7g/cm3, longitudinal wave and transverse wave speed are respectively cl=6.15km/s and ct=3.1km/s.Its material parameter is not completely fixed,
It can be changed in lesser range.Aluminium alloy plate thickness is (general to choose according to the Water Cutting equipment perforative plate thickness of institute's energy
Within 80mm).
Step 2: using the method for Water Cutting, requiring to be cut into through hole according to gradient design on aluminium alloy plate；Unit cell
Cross section geometry as shown in figure 3, lattice constant (the distance between adjacent aperture centers) be a=20mm.Except hexagonal hole
Other than diameter d, remaining four parameter is respectively b=0.0275a, e=0.32a, h=0.06a and t=0.05a.Hole along the y-axis direction
The size of diameter d determines that aperture does not change along the x-axis direction by designing stealthy frequency and the length of plate in the direction of the x axis.Embodiment
Middle to choose stealthy frequency as 25kHz, the length of plate is L=24a, then regular hexagon aperture d is followed successively by 0.5a along the size of y-axis,
0.507a,0.526a,0.556a,0.594a,0.636a,0.68a.Wherein, the size of stealthy frequency and lattice constant a be in etc.
Ratio variation.The variation of remaining four parameter can also cause the variation of stealthy frequency, such as b, h, and the reduction of t will cause stealthy frequency
The reduction of rate, and the reduction of e can be such that stealthy frequency increases.Fig. 1 and Fig. 2 is respectively overall structure diagram and three-dimensional structural map.Fig. 1 and
The circular cavity that the center Fig. 2 is cut out is stealthy region, and the diameter of cavity is not more than the half of board width (along the y-axis direction).
Step 3: porous Al alloy plate is glued together.Bonding front face will polish flat, and gluing will be prevented uniformly
Degumming and bonding are loosely.Specifically: since Water Cutting has certain limitations plate thickness, plane strain problems are required in z-axis direction
Plate thickness reaches ten times of lattice constant, it is therefore desirable to which the manufactured porous Al alloy plate of multilayer is glued together to meet thickness
It is required that.This porous plate is two-dimension phonon functional structure.
The beneficial effects of the present invention are:
The present invention by the directions of propagation of direct sound waves, so as to allow immersed body hide in a certain direction sonar or
The detection of other ultrasonic instruments helps submarine etc. to set under water so that it is stealthy to may be implemented underwater sound wave within the scope of certain frequency
The standby detection for hiding active sonar；
The impedance match of structure and water of the invention is high, can be realized high-transmission rate；
Structure of the invention need to only drill on alloy matrix aluminum and obtain, and the processing is simple.
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto,
In the technical scope disclosed by the present invention, any changes or substitutions that can be easily thought of by anyone skilled in the art,
It should be covered by the protection scope of the present invention.Therefore, protection scope of the present invention should be with scope of protection of the claims
Subject to.
Claims (9)
1. a kind of realize that underwater sound wave orients stealthy phonon functional structure, comprising:
Alloy matrix aluminum；
The through hole arranged according to plane positive triangle lattice period is drilled on the alloy matrix aluminum, the through hole is along Z axis side
To through the alloy matrix aluminum；
The through hole includes: regular hexagon hole；
Each side of the regular hexagon hole is connected with T-shaped hole.
2. phonon functional structure according to claim 1, it is characterised in that:
The centre of the alloy matrix aluminum is provided with the cavity for running through the alloy matrix aluminum along Z-direction, for placing to hidden
Hide target.
3. phonon functional structure according to claim 2, which is characterized in that
The diameter of the cavity is less than or equal to the half of the width of the alloy matrix aluminum along the y axis.
4. phonon functional structure according to claim 1, it is characterised in that:
The alloy matrix aluminum is symmetrical along the x axis；
The size of regular hexagon hole distribution gradient along the y axis, the refractive index gradient of the regular hexagon hole is along Y
Axis direction is hyperbolic secant distribution；
The regular hexagon hole is in distribution in the same size along the x axis, and the refractive index of the regular hexagon hole is along the x axis
It is uniformly distributed.
5. phonon functional structure according to claim 4, which is characterized in that
When stealthy frequency is 25kHz, the density of the alloy matrix aluminum is ρ=2.7g/cm3；The longitudinal wave of the alloy matrix aluminum
Velocity of wave and transverse wave speed are respectively cl=6.15km/s and ct=3.1km/s；
The lattice constant a=20mm of the regular hexagon hole；The length L=24a of the alloy matrix aluminum in the X-axis direction；
The size of the T-shaped hole be respectively as follows: the boundary of unit cell of the cross-drilled hole of T-shaped hole to the alloy matrix aluminum away from
From b=0.0275a, the length e=0.32a of the cross-drilled hole of T-shaped hole, width h=0.06a and the T word of the cross-drilled hole of T-shaped hole
The width t=0.05a of the vertical core of shape hole；
The aperture d of the regular hexagon hole is followed successively by 0.5a, 0.507a, 0.526a, 0.556a, 0.594a along the size of y-axis,
0.636a,0.68a。
6. phonon functional structure according to claim 5, which is characterized in that
The stealthy frequency and the size of the lattice constant a are changed in equal proportion；
The cross-drilled hole of T-shaped hole is to the distance b on boundary of unit cell of the alloy matrix aluminum, the width of the cross-drilled hole of T-shaped hole
H, so that stealthy frequency reduces, the reduction of the length e of the cross-drilled hole of T-shaped hole makes for the reduction of the width t of the vertical core of T-shaped hole
Stealthy frequency increases.
7. phonon functional structure according to claim 5, which is characterized in that
The alloy matrix aluminum Z-direction with a thickness of the lattice constant at least ten times.
8. a kind of production method realized underwater sound wave and orient stealthy phonon functional structure characterized by comprising
Select an alloy matrix aluminum；
The through hole arranged according to plane positive triangle lattice period is cut on the alloy matrix aluminum, the through hole is along Z
Axis direction runs through the alloy matrix aluminum, and the through hole includes regular hexagon hole；
Each side of the regular hexagon hole is connected with T-shaped hole；
At least two alloy matrix aluminum bondings of the through hole will be cut into, so that the alloy matrix aluminum after bonding
Z-direction with a thickness of lattice constant at least ten times.
9. the production method of phonon functional structure according to claim 8, which is characterized in that further include:
It is cut into the cavity through the alloy matrix aluminum in the centre of the alloy matrix aluminum, for placing target to be concealed.
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| CN108845291A (en) * | 2018-06-12 | 2018-11-20 | 江苏大学 | A kind of underwater sound source positioning system and method based on phonon crystal sensing |
| CN110880312B (en) * | 2018-09-05 | 2023-10-27 | 湖南大学 | Underwater sub-wavelength local resonance type acoustic metamaterial |
| CN115602141B (en) * | 2022-11-16 | 2023-03-10 | 青岛国数信息科技有限公司 | Active acoustic stealth method for frogman |
| CN116956688B (en) * | 2023-07-31 | 2023-12-22 | 中国船舶集团有限公司第七一九研究所 | Five-mode metamaterial cell and design method thereof |
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| CN103046480A (en) * | 2011-10-11 | 2013-04-17 | 无锡市德林环保工程有限公司 | Complete aluminum pierced noise-absorbing plate |
| US8836792B1 (en) * | 2010-12-13 | 2014-09-16 | Image Acoustics, Inc. | Active cloaking with transducers |
| CN104989939A (en) * | 2015-07-02 | 2015-10-21 | 辽宁融达新材料科技有限公司 | Punched foamed aluminum panel and manufacturing method thereof |
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|---|---|---|---|---|
| US8836792B1 (en) * | 2010-12-13 | 2014-09-16 | Image Acoustics, Inc. | Active cloaking with transducers |
| CN103046480A (en) * | 2011-10-11 | 2013-04-17 | 无锡市德林环保工程有限公司 | Complete aluminum pierced noise-absorbing plate |
| CN104989939A (en) * | 2015-07-02 | 2015-10-21 | 辽宁融达新材料科技有限公司 | Punched foamed aluminum panel and manufacturing method thereof |
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