CN108443631A - A kind of asymmetric acoustic propagation triangle superstructure - Google Patents
A kind of asymmetric acoustic propagation triangle superstructure Download PDFInfo
- Publication number
- CN108443631A CN108443631A CN201810328533.0A CN201810328533A CN108443631A CN 108443631 A CN108443631 A CN 108443631A CN 201810328533 A CN201810328533 A CN 201810328533A CN 108443631 A CN108443631 A CN 108443631A
- Authority
- CN
- China
- Prior art keywords
- triangle
- acoustic propagation
- superstructure
- asymmetric acoustic
- triangular prism
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/02—Energy absorbers; Noise absorbers
- F16L55/033—Noise absorbers
Abstract
The invention discloses a kind of asymmetric acoustic propagation triangle superstructures, the regular triangular prism 1 biased including one, 21 equilateral triangle resonant cavities (2 22) are arranged in 1 periphery of regular triangular prism, one equilateral triangle cavity 23 surrounds 21 equilateral triangle resonant cavities (2 22), and three sides of equilateral triangle cavity 23 are connected to rectangular waveguide 24,25 and 26 respectively.It is six identical right angled triangle helmholtz resonance chambers (27 32) inside each equilateral triangle resonant cavity.The asymmetric acoustic propagation triangle superstructure of the present invention, when regular triangular prism biases, which can make original tape gap be divided into two new band gap, and generate a new passband therebetween.Asymmetric acoustic propagation triangle superstructure modal distribution shows that two rectangular waveguides of regular triangular prism biased direction interconnect.Asymmetric acoustic propagation triangle superstructure can change direction and the transmission efficiency of acoustic propagation by adjusting the biasing of center regular triangular prism.
Description
Technical field
The present invention relates to acoustics helmholtz resonance, acoustic propagation control technology, sound scattering block bias structure and acoustics superjunction
Structure more particularly to a kind of asymmetric acoustic propagation triangle superstructure.
Background technology
Sound wave controlled is the significant challenge of current duct acoustics faced in pipe-line system.Pipeline itself is not generated and is made an uproar
Sound, but noise caused by the equipment such as the ventilation blower by being connected, air blower, compressor, water pump, oil pump and steam turbine lead to
Medium and pipeline itself in piping transmits.In addition, fluid generates hydrodynamic noise due to turbulent flow in the duct, hydrodynamic noise
It will increase with flowing velocity and increase.Pipeline sound wave is controlled, sonic propagation of making an uproar can be effectively blocked, reduces duct noise
Influence to surrounding enviroment.In addition, the propagation path to duct noise controls so that sound wave is according to preset path
It propagates, reaches pre- region, can greatly expand existing acoustic propagation control technology.Pipe can be effectively realized by rotary air at present
Road sound wave is propagated along free routing, but because of its stability and inherent noise, seriously affects the robustness of its sound wave controlled and reliable
Property, it is difficult to realize its engineer application.
Invention content
The technical problem to be solved in the present invention is to provide a kind of asymmetric acoustic propagation triangle superstructures, are controlled in pipeline
Sound transmission realizes that the orientation fixed point of sound is propagated.
In order to solve the above technical problems, the present invention provides a kind of asymmetric acoustic propagation triangle superstructures.Asymmetric sound
Propagate triangle superstructure：The regular triangular prism biased including one, 21 equilateral triangle resonant cavities, three sides difference
Connect the equilateral triangle cavity there are three rectangular waveguide.Each equilateral triangle resonant cavity is by six identical right angled triangle last of the twelve Earthly Branches nurses
Hereby resonant cavity is constituted suddenly.The tubule of helmholtz resonance chamber is connected to equilateral triangle cavity.
The improvement of asymmetric acoustic propagation triangle superstructure as the present invention：Asymmetric acoustic propagation triangle superstructure is adopted
With equilateral triangle cavity.
As being further improved for asymmetric acoustic propagation triangle superstructure of the invention：Three sides of equilateral triangle cavity
It is connected to a rectangular waveguide respectively.
As being further improved for asymmetric acoustic propagation triangle superstructure of the invention：The inside of equilateral triangle cavity has
Bias regular triangular prism.
As being further improved for asymmetric acoustic propagation triangle superstructure of the invention：The periphery of the regular triangular prism of biasing
For 21 equilateral triangle resonant cavities.
As being further improved for asymmetric acoustic propagation triangle superstructure of the invention：Equilateral triangle resonant cavity is by six
Identical right angled triangle helmholtz resonance chamber composition.
Compared with the background technology, the present invention, tool has the advantages that：
The larger material of rigidity (such as steel and aluminium alloy) processing can be used in the asymmetric acoustic propagation triangle superstructure
It forms, production cost is relatively low.The asymmetric acoustic propagation triangle superstructure of the present invention makes sound wave can in the equilateral triangle operatic tunes
The space squeezed by regular triangular prism biases.The asymmetric acoustic propagation triangle superstructure of the present invention makes sound wave can be positive three
It is propagated between two rectangular waveguides of prism biased direction.The asymmetric acoustic propagation triangle superstructure of the present invention can be assembled into two dimension
Acoustic propagation network, and the biased direction by adjusting regular triangular prism inside asymmetric acoustic propagation triangle superstructure, control sound pass
Direction is broadcast, realizes that sound is propagated along free routing.
The present invention is further illustrated in the following with reference to the drawings and specific embodiments.
Description of the drawings
Fig. 1 is a kind of asymmetric acoustic propagation triangle superstructure of the present invention；
Fig. 2 be the present invention a kind of asymmetric acoustic propagation triangle superstructure Bravais square dot matrix positive grid and
Reciprocal lattice figure；
Fig. 3 is a kind of band structure of asymmetric acoustic propagation triangle superstructure of the present invention；
Fig. 4 is a kind of acoustic pressure modal graph of asymmetric acoustic propagation triangle superstructure of the present invention；
Fig. 5 is the transmission function and acoustic pressure field pattern of a kind of asymmetric acoustic propagation triangle superstructure of the present invention.
Fig. 6 is the two-dimentional acoustic propagation network that the asymmetric acoustic propagation triangle superstructure of the present invention is assembled into, and marks it
A kind of middle acoustic propagation path.
Specific implementation mode
Fig. 1 gives a kind of asymmetric acoustic propagation triangle superstructure.Asymmetric acoustic propagation triangle superstructure is positive three
It is angular.1 regular triangular prism biased for one.Cylinder periphery is 21 equilateral triangle resonant cavities (2-22).21 just
The outside of triangle resonant cavity (2-22) is an equilateral triangle cavity 23.Three sides of one equilateral triangle cavity 23 connect respectively
There is rectangular waveguide 24,25 and 26.Each equilateral triangle resonant cavity includes six identical right angled triangle helmholtz resonance chambers
(27-32)。
The present invention's divides shape sound absorption superstructure operation principle as follows：
(1) geometric parameter of the asymmetric acoustic propagation triangle superstructure is L1=43.301mm, L2=214.77mm, L3
=77.942mm, X=43.301mm, a=34.641mm, b=1mm, c=1mm, t=1mm.
(2) as shown in Fig. 2, it is a unit cell to take two asymmetric acoustic propagation triangle superstructures, unit cell is placed in lattice
Constant is in the Bravais hexagonal lattices of 664.77mm.It is e=(e that the base of Bravais hexagonal lattices, which loses,1,e2).Any other is former
Born of the same parents can be defined as one group of integer to (n1,n2).Work as n1=0 and n2When=0, initial primitive unit cell is indicated.Other any primitive unit cells all may be used
With along e1Direction translates n1Step, along e2Direction translates n2It walks and obtains.
The response of lattice point r is represented by u (r) in initial primitive unit cell.Due to Bravais hexagonal-lattices be it is periodic, because
This primitive unit cell (n1,n2) acoustic pressure be also periodic：
U (r)=u (r+Rn) (1)
Wherein Rn=n1e1+n2e2It is lost for positive lattice.
The Fourier progression forms of periodic function u (r) are represented by：
Formula (2), which is substituted into formula (1), to be obtained：
Gj·Rn=2 π k (3)
Wherein GjFor the mistake of falling lattice, base mistake is represented by
(3) the band structure figure of the Finite element arithmetic structure is used.With linear elasticity, anisotropy and non-homogeneous Jie
The Time Migration of Elastic Wave Equation of matter is represented by：
Wherein r=(x, y, z) indicates that position is lost；U=(ux,uy,uz) indicate motion vector；Table
Show gradient operator；C (r) indicates elasticity tensor；ρ (r) indicates density tensor.
When elastic wave is monochromatic wave, motion vector u (r, t) is represented by：
U (r, t)=u (r) eiωt (5)
Whereinω indicates angular frequency.Formula (5) is substituted into formula (4), Time Migration of Elastic Wave Equation can be reduced to：
▽[C(r):▽·u(r,t)]+ω2ρ (r) u (r)=0 (6)
Since there is only longitudinal wave, the simple harmonic quantity ACOUSTIC WAVE EQUATION of fluid is represented by a fluid：
Wherein cl(r) it is the velocity of wave of longitudinal wave；P (r) indicates fluid field pressure.
Fluid structurecoupling interface need to meet normal direction particle acceleration and the normal pressure condition of continuity：
Wherein nfAnd nsIndicate the normal vector of fluid structurecoupling surfactant fluid and solid；V indicates Particle Vibration Velocity；pfTable
Show fluid field pressure；σijIndicate the components of stress of solid.
Spatially, Bravais dot matrix are infinite periods.Using Bloch theories, motion vector u (r) and flow field are pressed
Power p (r) can be expressed as
Wherein k=(kx,ky,kz) indicate that wave loses；uk(r) and pk(r) the cyclic shift vector sum week of lattice dot matrix is indicated
Phase property flow field vector.Bloch-Floquet conditions are applied on periodic boundary, and FInite Element can be used and fall into a trap in initial primitive unit cell
Calculate the band structure figure of the periodic structure.Initially the Discrete Finite Element eigenvalue equation of primitive unit cell is：
Wherein KsAnd KfFor the stiffness matrix of solid and fluid；MsAnd MfFor the mass matrix of solid and fluid；Q is that stream is solid
Coupling matrix.
To obtain complete band structure, if structure unit cell has enough symmetry, it should theoretically calculate all waves and lose k
Corresponding modal frequency.In Bloch theories, it is symmetrical and periodic that the wave for the disalignment of falling lattice, which loses k,.Therefore, wave loses k and can limit
Fixed the first irreducible areas Brillouin to the mistake of falling lattice.Further, since always to appear in first irreducible for the extreme value of band gap
The boundary in the areas Brillouin, therefore wave mistake k can further limit boundary X → Γ to the first irreducible areas Brillouin,
Γ → M and M → X.
(4) as shown in figure 3, it is when asymmetric acoustic propagation triangle superstructure center regular triangular prism does not bias to scheme a
Band structure figure, figure b are band structure figure when asymmetric acoustic propagation triangle superstructure center regular triangular prism biases.It is logical
Comparison is crossed, when can be clearly observed regular triangular prism and not biasing, it is the band of [2310Hz, 2390Hz] which, which has frequency range,
Gap.In the frequency range, sound wave can not be propagated by the operatic tunes between rectangular waveguide.When regular triangular prism cylinder biases, the band of the structure
Gap changes.Original tape gap [2310Hz, 2390Hz] be divided into two new band gap [2310Hz, 2370Hz] and [2373Hz,
2393Hz].Among two new band gap, a new passband [2370Hz, 2373Hz] is generated.Passband [2370Hz,
2373Hz] in, sound can be propagated by the operatic tunes between rectangular waveguide.
(5) the acoustic pressure distribution mode of asymmetric acoustic propagation triangle superstructure is as shown in Figure 4.Asymmetric acoustic propagation triangle
Superstructure modal distribution shows that two rectangular waveguides of regular triangular prism biased direction are interconnected, it can be achieved that acoustic propagation.
(6) transmission function of asymmetric acoustic propagation triangle superstructure is as shown in Figure 5.When frequency is 2371Hz, sound wave
Enter from the upper rectangular waveguide of superstructure, the cavity that regular triangular prism squeezes can be passed through, into right rectangular waveguide.Sound wave is from upper rectangle
The transmission efficiency of waveguide to right rectangular waveguide is 99.6%, and to the transmission efficiency of left rectangular waveguide close to zero.Scheme (5b) display
When sound wave is from left rectangular waveguide incidence, sound wave can not travel to other two sound rectangular waveguides, i.e. acoustic propagation is ended.It is non-right
Direction and the transmission efficiency for claiming acoustic propagation triangle superstructure that can change acoustic propagation by adjusting the biasing of center equilateral triangle column.
(6) grid (Fig. 6) constituted using asymmetric acoustic propagation triangle superstructure adjusts the inclined of center equilateral triangle column
Direction is set, it can be achieved that sound wave is along preset propagated, and reaches scheduled target area.
Finally, it should also be noted that it is listed above be only the present invention a specific embodiment.Obviously, of the invention
It is not limited to above example, acceptable there are many deformations, such as square, equilateral hexagon.Those skilled in the art
All deformations that directly can be exported or associate from present disclosure, are considered as protection scope of the present invention.
Claims (7)
1. a kind of asymmetric acoustic propagation triangle superstructure, including 1,21 equilateral triangles of regular triangular prism of a biasing are total
The chamber (2-22) that shakes is arranged in the periphery of regular triangular prism 1, and an equilateral triangle cavity 23 is by 21 equilateral triangle resonant cavity (2-
22) it surrounds, three sides of equilateral triangle cavity 23 are connected to rectangular waveguide 24,25 and 26 respectively.In each equilateral triangle resonant cavity
Portion is six identical right angled triangle helmholtz resonance chambers (27-32).
2. a kind of asymmetric acoustic propagation triangle superstructure according to claim 1, it is characterised in that：Asymmetric acoustic propagation
Triangle superstructure is equilateral triangle cavity.
3. a kind of asymmetric acoustic propagation triangle superstructure according to claim 1, it is characterised in that：Asymmetric acoustic propagation
The equilateral triangle cavity center of triangle superstructure is the regular triangular prism 1 of biasing.
4. a kind of asymmetric acoustic propagation triangle superstructure according to claim 1, it is characterised in that：Asymmetric acoustic propagation
The equilateral triangle cavity of triangle superstructure has 21 equilateral triangle resonant cavities (2-22).
5. a kind of asymmetric acoustic propagation triangle superstructure according to claim 1 and 4, it is characterised in that：21
Equilateral triangle resonant cavity (2-22) is evenly distributed in 1 periphery of biasing regular triangular prism.
6. a kind of asymmetric acoustic propagation triangle superstructure according to claim 1, it is characterised in that：Asymmetric acoustic propagation
Three sides of the equilateral triangle cavity 23 of triangle superstructure are connected to rectangular waveguide 24,25 and 26 respectively.
7. a kind of asymmetric acoustic propagation triangle superstructure according to claim 1 and 4, it is characterised in that：Each is just
It is six identical right angled triangle helmholtz resonance chambers (27-32) inside triangle resonant cavity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810328533.0A CN108443631A (en) | 2018-04-12 | 2018-04-12 | A kind of asymmetric acoustic propagation triangle superstructure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810328533.0A CN108443631A (en) | 2018-04-12 | 2018-04-12 | A kind of asymmetric acoustic propagation triangle superstructure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108443631A true CN108443631A (en) | 2018-08-24 |
Family
ID=63199822
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810328533.0A Pending CN108443631A (en) | 2018-04-12 | 2018-04-12 | A kind of asymmetric acoustic propagation triangle superstructure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108443631A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110880312A (en) * | 2018-09-05 | 2020-03-13 | 湖南大学 | Underwater sub-wavelength local resonance type acoustic metamaterial |
| CN110880311A (en) * | 2018-09-05 | 2020-03-13 | 湖南大学 | Underwater sub-wavelength space coiled acoustic metamaterial |
| CN110946580A (en) * | 2019-11-06 | 2020-04-03 | 中国人民解放军陆军军医大学第一附属医院 | Nuclear magnetic resonance detection system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4555433A (en) * | 1982-09-10 | 1985-11-26 | Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V. | Sound-absorbing element |
| CN106205590A (en) * | 2016-06-30 | 2016-12-07 | 湖南大学 | A kind of fractal sound absorption superstructure |
| CN106228969A (en) * | 2016-09-19 | 2016-12-14 | 四川大学 | A kind of three-dimensional locally resonant photonic crystal structure and preparation method |
| CN106652991A (en) * | 2016-10-27 | 2017-05-10 | 湖南大学 | Sound absorption superstructure |
| CN108615521A (en) * | 2018-04-12 | 2018-10-02 | 湖南大学 | A kind of sound topological insulator |
-
2018
- 2018-04-12 CN CN201810328533.0A patent/CN108443631A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4555433A (en) * | 1982-09-10 | 1985-11-26 | Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V. | Sound-absorbing element |
| CN106205590A (en) * | 2016-06-30 | 2016-12-07 | 湖南大学 | A kind of fractal sound absorption superstructure |
| CN106228969A (en) * | 2016-09-19 | 2016-12-14 | 四川大学 | A kind of three-dimensional locally resonant photonic crystal structure and preparation method |
| CN106652991A (en) * | 2016-10-27 | 2017-05-10 | 湖南大学 | Sound absorption superstructure |
| CN108615521A (en) * | 2018-04-12 | 2018-10-02 | 湖南大学 | A kind of sound topological insulator |
Non-Patent Citations (1)
| Title |
|---|
| HONGQING DAI,ETC.: ""Quasilossless acoustic transmission in an arbitrary pathway of a network",Hongqing Dai,etc., 054109-1至054109-6页，2017年2月10日", 《PHYSICAL REVIEW B》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110880312A (en) * | 2018-09-05 | 2020-03-13 | 湖南大学 | Underwater sub-wavelength local resonance type acoustic metamaterial |
| CN110880311A (en) * | 2018-09-05 | 2020-03-13 | 湖南大学 | Underwater sub-wavelength space coiled acoustic metamaterial |
| CN110880311B (en) * | 2018-09-05 | 2023-08-15 | 湖南大学 | Underwater sub-wavelength space coiling type acoustic metamaterial |
| CN110880312B (en) * | 2018-09-05 | 2023-10-27 | 湖南大学 | Underwater sub-wavelength local resonance type acoustic metamaterial |
| CN110946580A (en) * | 2019-11-06 | 2020-04-03 | 中国人民解放军陆军军医大学第一附属医院 | Nuclear magnetic resonance detection system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108443631A (en) | A kind of asymmetric acoustic propagation triangle superstructure | |
| Zhang et al. | Coupled vibration analysis of fluid-filled cylindrical shells using the wave propagation approach | |
| Desmet et al. | A computationally efficient prediction technique for the steady-state dynamic analysis of coupled vibro-acoustic systems | |
| CN106205590B (en) | Fractal sound absorption superstructure | |
| Mitri | Radiation forces and torque on a rigid elliptical cylinder in acoustical plane progressive and (quasi) standing waves with arbitrary incidence | |
| Li et al. | A BEM for band structure and elastic wave transmission analysis of 2D phononic crystals with different interface conditions | |
| CN110880312B (en) | Underwater sub-wavelength local resonance type acoustic metamaterial | |
| Mimani et al. | Transverse plane wave analysis of short elliptical chamber mufflers: An analytical approach | |
| Huang et al. | Multiple flexural-wave attenuation zones of periodic slabs with cross-like holes on an arbitrary oblique lattice: Numerical and experimental investigation | |
| Xiang et al. | Controlling sound transmission by space-coiling fractal acoustic metamaterials with broadband on the subwavelength scale | |
| Chen et al. | Multifunctional applications of topological valley-locked elastic waves | |
| Zhong et al. | Vibration characteristics and power flow analysis of irregular composite coupling laminated plate structures | |
| KR20160047503A (en) | Non-reciprocal acoustic devices based on linear or angular momentum biasing | |
| Xin et al. | Comprehensive analysis of band gap of phononic crystal structure and objective optimization based on genetic algorithm | |
| US11107452B2 (en) | Three-dimensional asymmetric lattice structure for tailoring the band gaps | |
| Torii et al. | GFEM for modal analysis of 2D wave equation | |
| Chen et al. | Modal analysis of flexural band gaps in a membrane acoustic metamaterial (MAM) and waveguides affected by shape characteristics | |
| Price et al. | Fluidelastic stability of a rotatedsquare array with multiple flexible cylinders, subject to cross-flow | |
| Wen et al. | The directional propagation characteristics of elastic wave in two-dimensional thin plate phononic crystals | |
| Riazat et al. | Three-dimensional nonlinear dynamics of imperfectly supported pipes conveying fluid | |
| CN110880311B (en) | Underwater sub-wavelength space coiling type acoustic metamaterial | |
| Tang et al. | Directional transmission characteristics of acoustic waves based on artificial periodic structures | |
| Gulia et al. | Multi-directional Sound Reduction by Slitted Sonic Crystal | |
| Geyer et al. | Passive control of the vortex shedding noise of a cylinder at low Reynolds numbers using flexible flaps | |
| Darinskii et al. | Acoustic wave degeneracies in two-dimensional phononic crystals |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20180824 |
|
| WD01 | Invention patent application deemed withdrawn after publication |