CN114242027B - Composite sound absorption super-structured surface based on porous material - Google Patents
Composite sound absorption super-structured surface based on porous material Download PDFInfo
- Publication number
- CN114242027B CN114242027B CN202210106593.4A CN202210106593A CN114242027B CN 114242027 B CN114242027 B CN 114242027B CN 202210106593 A CN202210106593 A CN 202210106593A CN 114242027 B CN114242027 B CN 114242027B
- Authority
- CN
- China
- Prior art keywords
- cavity
- vertical cavity
- horizontal
- composite
- sound absorption
- 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.)
- Active
Links
- 239000002131 composite material Substances 0.000 title claims abstract description 121
- 238000010521 absorption reaction Methods 0.000 title claims abstract description 102
- 239000011148 porous material Substances 0.000 title claims abstract description 28
- 238000000926 separation method Methods 0.000 claims abstract description 46
- 239000006261 foam material Substances 0.000 claims abstract description 39
- 239000006260 foam Substances 0.000 claims description 8
- 229920000877 Melamine resin Polymers 0.000 claims description 5
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 claims description 5
- 230000001105 regulatory effect Effects 0.000 claims description 5
- 238000006073 displacement reaction Methods 0.000 claims description 3
- 239000006262 metallic foam Substances 0.000 claims description 3
- 230000004044 response Effects 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 18
- 230000000737 periodic effect Effects 0.000 abstract description 10
- 230000009467 reduction Effects 0.000 abstract description 6
- 238000013461 design Methods 0.000 abstract description 5
- 239000011358 absorbing material Substances 0.000 description 6
- 238000004364 calculation method Methods 0.000 description 5
- 238000004088 simulation Methods 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000010146 3D printing Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- RNFJDJUURJAICM-UHFFFAOYSA-N 2,2,4,4,6,6-hexaphenoxy-1,3,5-triaza-2$l^{5},4$l^{5},6$l^{5}-triphosphacyclohexa-1,3,5-triene Chemical compound N=1P(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP=1(OC=1C=CC=CC=1)OC1=CC=CC=C1 RNFJDJUURJAICM-UHFFFAOYSA-N 0.000 description 1
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 241000282414 Homo sapiens Species 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000003063 flame retardant Substances 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
- 125000006850 spacer group Chemical group 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/162—Selection of materials
-
- 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
- G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
- G10K2210/10—Applications
- G10K2210/128—Vehicles
- G10K2210/1281—Aircraft, e.g. spacecraft, airplane or helicopter
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Abstract
The invention provides a composite sound absorption super-structure surface based on a porous material, which comprises a plurality of composite sound absorption super-structure units which are arranged according to one-dimensional linear period or two-dimensional linear period; each composite sound absorption super-structure unit comprises a rigid cavity structure and a porous foam material; the rigid cavity structure is provided with a separation insert plate and a horizontal protrusion. The composite sound absorption super-structured surface based on the porous material provided by the invention is a sound absorption structure with a periodic structure array, has a broadband sound absorption effect and a vibration reduction effect, particularly has an excellent absorption effect on low-frequency noise, and can realize a wider-band sound absorption effect by being matched with the combined application of a plurality of different periodic structures. Specifically, the design of the tortuous cavity channel and the application of foam materials with corresponding parameters are matched, so that the sound absorption performance of the tortuous cavity channel for noise in a plurality of specific frequency bands, which is close to 100%, can be realized, and the tortuous cavity channel has good application prospects.
Description
Technical Field
The invention belongs to the technical field of sound absorption and noise reduction, and particularly relates to a composite sound absorption super-structured surface based on a porous material.
Background
The rapid development of modern society has led to the gradual manifestation of environmental pollution problems. Noise pollution is used as an environmental pollution and generates great harm to the production and life of human beings. Among them, the noise problem in aerospace, transportation and industrial production is particularly serious. In the operation process of the aviation aircraft, great noise can be generated, and the noise can be influenced by the normal life and rest of residents in the vicinity of an airport, especially the noise of the aircraft. Increasingly more attention and importance is being paid to aircraft noise pollution, and noise reduction at sound sources is often the most effective and economical noise control measure. Therefore, the sound absorbing material is widely applied, and the occupied area and thickness of the sound absorbing material are limited due to the restrictions of the use scene and the application.
In aviation noise control engineering, noise control by sound absorbing materials is a widely used noise control means. However, with general sound absorbing materials such as porous materials, sound absorbing effects are good only for high frequency noise, it is difficult for low frequency noise to be absorbed, and in order to improve sound absorbing effects, only by increasing the thickness or density of the sound absorbing material or structure can be achieved. In practical production and application, the weight and thickness of the sound absorption device are required to be certain, and the sound absorption device is convenient to install.
In summary, the conventional sound absorbing material and structure only has good sound absorbing effect on medium and high frequency, and cannot play an effective sound absorbing effect on low frequency band. Therefore, how to reduce the weight and thickness without reducing the noise, especially the absorption of low-frequency noise, has great significance for military and civil fields.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention provides a composite sound absorption super-structured surface based on a porous material, which can effectively solve the problems.
The technical scheme adopted by the invention is as follows:
the invention provides a composite sound absorption super-structure surface based on a porous material, which comprises a plurality of composite sound absorption super-structure units (1) which are arranged according to one-dimensional linear period or two-dimensional linear period;
each composite sound absorption super-structure unit (1) comprises a rigid cavity structure (1-1) and a porous foam material (1-2); the rigid cavity structure (1-1) comprises A horizontal cavity (A1), wherein the surfaces of the horizontal cavity (A1) are sequentially provided with A1 st vertical cavity, A2 nd vertical cavity, … th vertical cavity and an n-th vertical cavity which are communicated with the horizontal cavity (A1) at equal intervals in the direction from the left end to the right end; the 1 st vertical cavity and the n vertical cavity are edge cavities, the 2 nd vertical cavity is …, and the n-1 st vertical cavity is a middle cavity; the width d1 of the edge cavity is half of the width d2 of the middle cavity; the heights of the edge cavity and the middle cavity are the same;
A separation plugboard (1-3) is vertically arranged in the center of each middle cavity; the bottom of the separation plugboard (1-3) extends to the bottom of the horizontal cavity (A1); the top of the separation plugboard (1-3) and the top of the middle cavity are provided with a certain gap, and the gap is further adjusted by adjusting the height of the separation plugboard (1-3), and the height of the gap is adjusted according to the wavelength of the absorbed sound wave; therefore, the center of the 2 nd vertical cavity is provided with the 2 nd separation plugboard, the center of the 3 rd vertical cavity is provided with the 3 rd separation plugboard, …, and the center of the n-1 th vertical cavity is provided with the n-1 th separation plugboard; inside the rigid cavity structure (1-1), forming a tortuous cavity channel by arranging each separation plugboard (1-3) so as to enable the inner cavity of the rigid cavity structure (1-1);
The right side of the 2 nd vertical cavity is provided with a2 nd horizontal bulge communicated with the 2 nd vertical cavity; the right side of the 3 rd vertical cavity is provided with a 3 rd horizontal protrusion communicated with the 3 rd vertical cavity; and the right side of the nth vertical cavity is provided with an nth horizontal protrusion communicated with the nth vertical cavity; the surface phase of the composite sound absorption super-structure unit (1) is adjusted by setting the length of the 2 nd horizontal bulge, the thickness of the 2 nd horizontal bulge and the height of the setting position of the 2 nd horizontal bulge, the length of the 3 rd horizontal bulge, the thickness of the 3 rd horizontal bulge and the height of the setting position of the 3 rd horizontal bulge, …, the length of the nth horizontal bulge, the thickness of the nth horizontal bulge and the height of the setting position of the nth horizontal bulge; wherein, the height of the setting position of each horizontal bulge refers to the distance between the horizontal bulge and the bottom surface of the rigid cavity structure (1-1);
The spacing space between the 1 st vertical cavity and the 2 nd vertical cavity forms a1 st porous foam material embedded cavity;
the spacing space between the 2 nd vertical cavity and the 3 rd vertical cavity forms a 2 nd porous foam material embedded cavity;
…
the n-1 th vertical cavity and the interval space between the n-1 th vertical cavities form an n-1 th porous foam material embedded cavity;
The 1 st porous foam material is embedded into the cavity, the 2 nd porous foam material is embedded into the cavity, … th porous foam material is embedded into the cavity, and the n-1 st porous foam material is respectively embedded into the porous foam materials.
Preferably, each of the composite sound absorption super-structure units (1) comprises n-1 composite structure subunits;
Wherein:
A1 st composite structure subunit is formed between the left side of the 1 st vertical cavity and the 2 nd separation plugboard;
A2 nd composite structure subunit is formed between the left side of the 2 nd vertical cavity and the 3 rd separation plugboard;
an n-1 composite structure subunit is formed between the n-1 separation plugboard and the right side of the n vertical cavity.
Preferably, each of the composite sound absorbing super-structure units (1) comprises 4 or 8 composite structure subunits.
Preferably, the length L3, the thickness H2 and the setting position height H3 of the horizontal protrusion of each composite structure subunit are selected according to the vibration displacement response of the composite structure subunit, and the phase of the reflected sound wave is regulated and controlled within the range of 0-2 pi.
Preferably, the lengths of the sub units of the composite structure are equal, L2 is adopted, and the heights are H1;
Then:
the length l3= (0-0.5) L2 of the horizontal protrusion of each composite structural subunit; thickness h2= (0-0.1) H1 of the horizontal protrusion; the setting position height h3= (0-1) H1 of the horizontal protrusion.
Preferably, when n=5, the 2 nd vertical cavity, the 3 rd vertical cavity, the 4 th vertical cavity and the 5 th vertical cavity set up the horizontal protrusion by adopting the following modes respectively:
The horizontal protrusions of the 2 nd vertical cavity have the following parameters: l3= (0.2-0.4) L2; h3 = (0.6-0.7) H1; h2 = (0-0.1) H1;
The horizontal protrusions of the 3 rd vertical cavity set have the following parameters: l3=0; h3 =0, h2=0, i.e.: no horizontal protrusions are arranged;
The horizontal protrusions of the 4 th vertical cavity have the following parameters: l3= (0.2-0.4) L2; h3 =h1; h2 = (0-0.1) H1;
The horizontal protrusions of the 5 th vertical cavity have the following parameters: l3= (0.2-0.4) L2; h3 =h1; h2 = (0 to 0.1) H1.
Preferably, the width d1= (0-0.2) L2 of the edge cavities of the respective composite structural subunits.
Preferably, the height of the separation insert plate of each composite structure subunit is H4; h4 = (0.5-0.99) H1.
Preferably, the porous foam material (1-2) adopts melamine foam or metal foam;
the length L2 of each composite structure subunit is 10-30 mm, and the height H1 is 20-50 mm; the wall thickness of the cavity wall of the rigid cavity structure (1-1) is 0.3-3 mm; the thickness of the separation plugboard (1-3) is 1-10 mm.
Preferably, the top surface of the 1 st vertical cavity is a cavity channel inlet, a microperforated panel (1-4) is arranged on the top surface of the 1 st vertical cavity, and the thickness of the microperforated panel (1-4) is the same as the thickness of the outer wall surface of the rigid cavity structure (1-1);
The micro-perforated plate (1-4) is provided with a plurality of micro through holes (1-4-1); the micro through holes (1-4-1) are uniformly distributed in a regular manner; the number and the diameter of the micro through holes (1-4-1) are selected according to the foam porosity and the surface impedance requirement of the composite sound absorption super-structure surface of the porous material.
The composite sound absorption super-structure surface based on the porous material has the following advantages:
The composite sound absorption super-structure surface based on the porous material provided by the invention is a sound absorption structure with a periodic structure array, is easy to process, splice and assemble, low in cost, high in structural strength and rigidity, small in density, light in weight, thin in thickness, fireproof and thermal insulation, can be applied to an airplane body, a ship cabin, a building wall body and an industrial sound absorption and noise reduction structure, has a wide-band sound absorption effect and a vibration reduction effect, particularly has an excellent low-frequency noise absorption effect, and can realize a wide-band sound absorption effect by being matched with the combined application of a plurality of different periodic structures. Specifically, the design of the tortuous cavity channel and the application of foam materials with corresponding parameters are matched, so that the sound absorption performance of the tortuous cavity channel for noise in a plurality of specific frequency bands, which is close to 100%, can be realized, and the tortuous cavity channel has good application prospects.
Other features and characteristics of the present invention will be described in detail in the examples of composite sound absorbing super-construction surface designs based on the present porous materials.
Drawings
FIG. 1 is a schematic view of a rigid cavity structure according to the present invention;
FIG. 2 is a front view of a composite sound absorptive super-structure unit provided by the present invention;
FIG. 3 is a front view of the composite sound absorbing super-structure unit provided by the invention with structural dimension marks added;
FIG. 4 is a schematic diagram of the phase distribution of reflected sound waves of the composite sound absorption super-structure unit provided by the invention;
FIG. 5 is a schematic diagram of a condition setting for finite element software simulation calculation according to the present invention;
FIG. 6 is a graph of the transmission profile of reflected sound waves of a0 degree incident sound wave in a composite sound absorbing super-structure surface;
FIG. 7 is a graph of the transmission profile of reflected sound waves of 30 degrees incident sound waves in a composite sound absorbing super-structure surface;
FIG. 8 is a graph of sound absorption coefficients calculated when the composite sound absorption super-structured surface provided by the invention is subjected to sound absorption test;
FIG. 9 is a graph comparing sound absorption coefficient curves;
Fig. 10 is a diagram of an arrangement mode of two-dimensional linear periodic arrangement of composite sound absorption super-structure units.
Wherein:
1-a composite sound absorption super-structure unit;
1-1-rigid cavity structure; a1-a horizontal cavity; a2-a vertical cavity; a3-horizontal protrusions;
1-2-porous foam material;
1-3-separating plugboards;
1-4-microperforated panels; 1-4-1-minute through holes;
1-5-front wall panel;
1-6-rear wall panel.
Detailed Description
The following describes the embodiments of the present invention further with reference to the drawings. The illustrative embodiments of the invention and their description are for the purpose of explaining the invention and are not intended to be exhaustive of all embodiments according to the invention. It is to be understood that some modifications or combinations of this structure may be made for other embodiments without departing from the scope of the invention.
In the following detailed description, unless otherwise specifically indicated, the terms "upper, middle, lower, forward, reverse, inner, outer" are used generally to refer to the terms upper, middle, lower, forward, reverse, inner, outer in the drawings. The components of the embodiments of the present invention may be positioned in a variety of different orientations and are not intended to limit the present invention.
In order to make up for the defect of the existing acoustic super surface on noise, especially low-frequency noise absorption effect, the invention provides a composite sound absorption super-structure surface based on a porous material, solves the contradiction between the quality, thickness and sound absorption effect of a sound absorption structure, realizes broadband sound absorption by using smaller thickness, and particularly has excellent sound absorption effect on low-frequency noise below 1000 Hz.
The invention provides a composite sound absorption super-structured surface based on a porous material, which mainly comprises a porous foam material, a rigid cavity structure which is embedded in the porous foam material and is periodically arranged, wherein the rigid cavity structure consists of horizontal protrusions, a zigzag cavity channel, a separation plugboard and a micro-perforated plate positioned at one side of the cavity structure, and the micro-perforated plate is provided with micro through holes with a certain size and a certain arrangement mode.
The invention provides a composite sound absorption super-structure surface based on a porous material, referring to figures 1-3, comprising a plurality of composite sound absorption super-structure units 1 which are arranged according to one-dimensional linear period or two-dimensional linear period;
Each composite sound absorption super-structure unit 1 comprises a rigid cavity structure 1-1 and a porous foam material 1-2; the porous foam material 1-2 adopts melamine foam or metal foam, preferably melamine foam, and the melamine foam can reach the B1 grade specified in GB/T8624-2012 under the condition of no flame retardant medium, and has excellent sound absorption, low volume weight and heat insulation, so that the composite sound absorption super-structured surface has wide application prospect.
The rigid cavity structure 1-1 comprises A horizontal cavity A1, wherein the surfaces of the horizontal cavity A1 are sequentially provided with A1 st vertical cavity, A2 nd vertical cavity, … th vertical cavity and an n-th vertical cavity which are communicated with the horizontal cavity A1 at equal intervals in the direction from the left end to the right end; the 1 st vertical cavity and the n vertical cavity are edge cavities, the 2 nd vertical cavity is …, and the n-1 st vertical cavity is a middle cavity; the width d1 of the edge cavity is half of the width d2 of the middle cavity; the heights of the edge cavity and the middle cavity are the same;
The center of each middle cavity is vertically provided with a separation plugboard 1-3; the bottom of the separation plugboard 1-3 extends to the bottom of the horizontal cavity A1; the top of the separation plugboard 1-3 and the top of the middle cavity are provided with a certain gap, the gap is further adjusted by adjusting the height of the separation plugboard 1-3, and the height of the gap is adjusted according to the wavelength of the absorbed sound wave; therefore, the center of the 2 nd vertical cavity is provided with the 2 nd separation plugboard, the center of the 3 rd vertical cavity is provided with the 3 rd separation plugboard, …, and the center of the n-1 th vertical cavity is provided with the n-1 th separation plugboard; inside the rigid cavity structure 1-1, through arranging each separation plugboard 1-3, the inner cavity of the rigid cavity structure 1-1 forms a zigzag cavity channel; the overall equivalent length of the tortuous cavity channel of the rigid cavity structure 1-1 is designed to be 20-80 mm, and the corresponding length is set according to the noise reduction requirement and the frequency of the sound wave to be absorbed.
The right side of the 2 nd vertical cavity is provided with a 2 nd horizontal bulge communicated with the 2 nd vertical cavity; the right side of the 3 rd vertical cavity is provided with a 3 rd horizontal protrusion communicated with the 3 rd vertical cavity; and the right side of the nth vertical cavity is provided with an nth horizontal protrusion communicated with the nth vertical cavity; the surface phase of the composite sound absorption super-structure unit 1 is adjusted by setting the length of the 2 nd horizontal bulge and the distance from the horizontal cavity A1, the length of the 3 rd horizontal bulge and the distance from the horizontal cavity A1, …, the length of the n-th horizontal bulge and the distance from the horizontal cavity A1;
The spacing space between the 1 st vertical cavity and the 2 nd vertical cavity forms a1 st porous foam material embedded cavity;
the spacing space between the 2 nd vertical cavity and the 3 rd vertical cavity forms a 2 nd porous foam material embedded cavity;
…
the n-1 th vertical cavity and the interval space between the n-1 th vertical cavities form an n-1 th porous foam material embedded cavity;
The 1 st porous foam material is embedded in the cavity, the 2 nd porous foam material is embedded in the cavity, … th porous foam material is embedded in the cavity of the cavity, and the porous foam materials are respectively embedded in the cavities.
In the invention, each composite sound absorption super-structure unit 1 comprises n-1 composite structure subunits;
Wherein:
A1 st composite structure subunit is formed between the left side of the 1 st vertical cavity and the 2 nd separation plugboard;
A 2 nd composite structure subunit is formed between the left side of the 2 nd vertical cavity and the 3 rd separation plugboard;
an n-1 composite structure subunit is formed between the n-1 separation plugboard and the right side of the n vertical cavity.
In the invention, each composite sound absorption super-structure unit 1 comprises 4 or 8 composite structure subunits, and the sound wave phase is regulated and controlled within the range of 0-2 pi. In addition, the front and rear surfaces of each composite sound absorption super structure unit 1 may be respectively provided with front wall panels 1-5 and rear wall panels 1-6 to be covered.
The following describes the major dimensions of the invention in detail:
First, composite sound absorption super-structure unit 1 size
The length and height of the composite sound absorption super-structure unit 1 can be adjusted in a small range according to the structural strength and the size of the internal cavity channel.
The composite sound absorption super-structure unit 1 can adopt the following dimensions: the length L1 of the composite sound absorption super-structure unit 1 is 40-180 mm, and the height H1 is 20-50 mm;
the length L2 of each composite structure subunit is 10-30 mm, and the height is equal to the height H1 of the composite sound absorption super-structure unit 1.
In the invention, the composite sound absorption super-structure unit 1 adjusts the surface phase of the composite sound absorption super-structure unit by controlling the length L3, the thickness H2 and the setting position height H3 of each horizontal protrusion.
(II) size of horizontal protrusions
The dimensions of each horizontal projection may be:
The length L3, the thickness H2 and the setting position height H3 of each horizontal protrusion are selected according to the vibration displacement response of the composite sound absorption super-structure surface, and the phase of the reflected sound wave is regulated and controlled within the range of 0-2 pi.
Wherein the length l3= (0-0.5) ×l2 of the horizontal protrusion of each composite structural subunit; thickness h2= (0-0.1) H1 of the horizontal protrusion; the setting position height h3= (0-1) H1 of the horizontal protrusion. .
As a specific example: when n=5, the 2 nd vertical cavity, the 3 rd vertical cavity, the 4 th vertical cavity and the 5 th vertical cavity set up the horizontal protrusion by adopting the following modes respectively:
The horizontal protrusions of the 2 nd vertical cavity have the following parameters: l3= (0.2-0.4) L2; h3 = (0.6-0.7) H1; h2 = (0-0.1) H1;
The horizontal protrusions of the 3 rd vertical cavity set have the following parameters: l3=0; h3 =0, h2=0, i.e.: no horizontal protrusions are arranged;
The horizontal protrusions of the 4 th vertical cavity have the following parameters: l3= (0.2-0.4) L2; h3 =h1; h2 = (0-0.1) H1;
The horizontal protrusions of the 5 th vertical cavity have the following parameters: l3= (0.2-0.4) L2; h3 =h1; h2 = (0 to 0.1) H1.
As a preferred mode, the following specific values may be used:
The horizontal protrusions of the 2 nd vertical cavity have the following parameters: l3=0.3×l2; h3 =0.65×h1; h2 =0.08×h1;
The horizontal protrusions of the 3 rd vertical cavity set have the following parameters: l3=0; h3 =0, h2=0, i.e.: no horizontal protrusions are arranged;
The horizontal protrusions of the 4 th vertical cavity have the following parameters: l3=0.3×l2; h3 =h1; h2 =0.08×h1;
the horizontal protrusions of the 5 th vertical cavity have the following parameters: l3=0.3×l2; h3 =h1; h2 =0.08×h1.
The arrangement mode of each horizontal protrusion is regulated, so that the regulation and control of the sound wave phase range of 0-2 pi is realized.
(III) relative part wall thickness and height
The wall thickness of the cavity wall of the rigid cavity structure 1-1 is 0.3-3 mm; the width d1= (0-0.2) L2 of the edge cavity of each composite structural subunit.
The thickness of the separation plugboard 1-3 is 1-10 mm. The height of the spacer plates 1-3 can be adjusted according to the wavelength of the absorbed sound waves.
As a preferred mode, the height of the separation plugboard of each composite structure subunit is H4; h4 = (0.5-0.99) H1.
(IV) microperforated panels
In the invention, the top surface of the 1 st vertical cavity is a cavity channel inlet, the top surface of the 1 st vertical cavity is provided with a microperforated panel 1-4, and the thickness of the microperforated panel 1-4 is the same as the thickness of the outer wall surface of the rigid cavity structure 1-1;
The micro-perforated plate 1-4 is provided with a plurality of micro through holes 1-4-1; the micro through holes 1-4-1 are uniformly distributed in a regular manner; the number and the diameter of the micro through holes 1-4-1 are selected according to the foam porosity and the surface impedance requirement of the composite sound absorption super-structure surface of the porous material.
All rigid structures in the composite sound absorption super-structure unit 1, including the outer wall surfaces of the microperforated panel, the separation plugboard and the rigid cavity structure, are preferably made of the same rigid material, and are integrally formed by 3D printing.
An experimental example is described below:
As a specific example: n=5, the 2 nd vertical cavity, the 3 rd vertical cavity, the 4 th vertical cavity and the 5 th vertical cavity are respectively provided with horizontal protrusions in the following manner:
The horizontal protrusions of the 2 nd vertical cavity have the following parameters: l3=0.3×l2; h3 =0.65×h1; h2 =0.08×h1;
The horizontal protrusions of the 3 rd vertical cavity set have the following parameters: l3=0; h3 =0, h2=0, i.e.: no horizontal protrusions are arranged;
The horizontal protrusions of the 4 th vertical cavity have the following parameters: l3=0.3×l2; h3 =h1; h2 =0.08×h1;
the horizontal protrusions of the 5 th vertical cavity have the following parameters: l3=0.3×l2; h3 =h1; h2 =0.08×h1.
According to classical acoustic theory, planar acoustic waves follow the snell law in their propagation behavior as they pass from one medium to another. However, if there is an additional phase distribution at the interface of two media, i.e. the wave propagation produces a sudden phase change at the interface, there will be a new relationship between reflection angle, refraction angle and incidence angle, as shown in the following formula:
Wherein:
θ i: an angle of incidence of the acoustic wave;
θ r: angle of reflection of sound wave;
Lambda: the wavelength of the incident sound wave;
m: diffraction orders;
L1: the length of the composite sound absorption super-structure unit;
In the composite sound absorption super-structure surface provided by the invention, the phase of the structural surface of a single composite structural subunit can be adjusted by changing the length L3 and the height H3 of the horizontal protrusion, so that the range of the structural surface covers 0-pi, and through verification, abnormal control of the range of 0-2 pi of sound waves can be realized when the phase change of the composite sound absorption super-structure surface covers pi. When the length L1 of the composite sound absorption super-structure unit is smaller than 1/2 of the wavelength, that is, λ/L1 > 2, the reflected wave of m= ±1 order occupying the main sound wave energy at this time is converted into a surface wave propagating along the surface of the material, as shown in fig. 6 and 7, the structure only has a specular reflected wave of m=0 order at this time, and the absorption efficiency of the sound wave is highest at this time.
The phase of the composite sound absorbing super-structure unit and the sound absorbing properties of the overall structure were measured using COMSOL Multiphysics commercial finite element software. In numerical calculation, the reflected sound wave of each composite sound absorption super-structure unit is firstly studied independently, and the phase of each composite sound absorption super-structure unit is obtained through point calculation. The setting of the simulation calculation is shown in fig. 5, and the composite sound absorption super-structure units are periodically arranged with the hard acoustic boundary as the boundary condition. To simulate an infinite computational domain, periodic boundaries are imposed on the sides. A Perfect Matching Layer (PML) is placed in the far field to simulate the infinite domain of the pressure wave, eliminating the effects of spurious reflections. The temperature in the model input conditions was 293.15K and the absolute pressure was 1 atm. The plane wave is used as a background sound field, sound waves impact the upper surface of the whole structure, and reflected waves under complex pressure can be directly obtained in simulation, so that phases are extracted on the fixed lines A-B. The phase can be adjusted by changing the length, thickness and setting position height of the horizontal protrusion inside each composite sound absorption super-structure unit, so that the phase difference between two adjacent composite sound absorption super-structure units is kept consistent. The position of the measuring line A-B can be at any position of the transmission area, but the position of the measuring line A-B cannot be moved when the phases of each independent composite sound absorption super-structure units are compared. The sound absorption performance of the whole structure is measured in a similar way, the distribution condition of the reflected sound wave is obtained through simulation, and the sound absorption coefficient of the structure is calculated by combining known incident sound wave parameters.
On the basis of the structure, a micro-perforated plate 1-4 with the thickness of L1/20mm is arranged at the inlet of one side of the cavity channel, and a plurality of micro through holes 1-4-1 with the diameter of L1/20mm are uniformly distributed on the micro-perforated plate. The addition of microperforated panels 1-4 does not affect the surface phase variation of the overall structure, and therefore the structure has good low frequency sound absorption properties while maintaining sound wave regulation and sound absorption properties at a design frequency of 2750 Hz.
The rigid cavity structure 1-1 is internally provided with a zigzag cavity channel through the separation plugboard 1-3, the height of the separation plugboard is (0.5-0.99×h1, preferably can be H1-d 1), the thickness H2 of the horizontal bulge is approximately equal to the width d1 of the edge cavity, the effective length of the zigzag cavity channel is approximately 5l1 cm, according to the impedance theory calculation of the micro-perforated plate sound absorption system, 1/4 of the sound wave wavelength of 300Hz is equivalent to the effective length of the zigzag cavity channel, therefore, better sound absorption effect can be obtained at the frequency, and in addition, the structure can also generate high-order absorption peaks at odd times of 300Hz such as 900Hz,1500Hz and the like, as shown in fig. 8.
The acoustic performance of the composite sound absorption super-structure surface is calculated by using a numerical simulation method, and as shown in fig. 9, the result shows that the composite sound absorption super-structure surface has good sound absorption effect at the low frequency parts 300Hz,900Hz and 1500Hz, and the sound absorption coefficient exceeds 0.9. In the high-frequency part, the composite sound absorption super-structure surface has better sound absorption performance in a wider frequency range, which is not weaker than that of a uniform foam material with the same thickness, the sound absorption coefficient of a frequency band of 2000-4000 Hz is more than 0.8, the sound absorption coefficient is close to 1 near the design frequency of 2750Hz, and the sound absorption coefficient is more than that of the uniform foam material with the same height (H1).
Referring to fig. 10, in the case of the two-dimensional linear periodic arrangement of the super-structured surface, a longitudinal periodic arrangement is added to the sound absorbing panel of the second embodiment of the present invention, and the periodic arrangement of the super-structured units of the composite sound absorbing panel is maintained in both the transverse and longitudinal directions as viewed in plane.
In fig. 10, 1,2,3,4 represent 4 composite structural subunits, respectively. The 4 composite structural subunits form a composite sound absorption super-structure unit. The composite sound absorption super-structure units are arranged periodically.
The overall height of the sound absorbing plate is 3cm, the length of 1 composite structure subunit is 6cm, and the phase of the surface of the structure is adjusted by controlling the length, thickness and setting position height of the horizontal protrusions of the rigid cavity structure.
In the periodic sequence, the length of the horizontal protrusion of the 1 st composite structure subunit is about 0.5cm, the height of the setting position is 2cm, and the thickness is 2.4mm; the length of the horizontal protrusion of the 2 nd composite structure subunit is 0, i.e. no horizontal protrusion is arranged; the length of the horizontal bulge of the 3 rd composite structure subunit is about 0.33cm, the height of the setting position is 3cm, and the thickness is 2.4mm; the length of the horizontal protrusion of the 4 th composite structure subunit is about 0.5cm, the height of the setting position is 3cm, and the thickness is 2.4mm. The wall thickness of the rigid cavity structure embedded into the foam material is 0.3mm, the micro-perforated plate with the thickness of 0.3mm is arranged at the inlet of the cavity, and a plurality of micro through holes with the diameter of 0.3mm are uniformly distributed on the micro-perforated plate. In this embodiment, three separation inserts are provided, the three separation inserts are equal in height and each have a thickness of 2.7cm and a thickness of 1mm, and the effective length of the tortuous cavity channel is about 28cm.
The micro-perforated plate, the outer wall surface of the cavity, the horizontal protrusions, the separation plugboards and the rear wall plate of the rigid cavity structure in the sound absorption plate structure are integrally formed by adopting aluminum alloy 3D printing, and the front wall plate can be fixed in an adhesive mode after being filled with porous foam materials.
It is pointed out here that a composite sound absorbing super-structured surface based on porous material according to the invention, as a general sound absorbing structure, can be used in various applications, such as cabin wall boards, engines, sound liner building walls, etc., the above specific embodiments merely illustrate the preferred implementation of the present example, but any combination of the various different embodiments of the invention is possible, as long as it does not deviate from the inventive idea, which should also be regarded as being within the scope of the present disclosure.
Claims (10)
1. The composite sound absorption super-structure surface based on the porous material is characterized by comprising a plurality of composite sound absorption super-structure units (1) which are arranged according to one-dimensional linear period or two-dimensional linear period;
each composite sound absorption super-structure unit (1) comprises a rigid cavity structure (1-1) and a porous foam material (1-2); the rigid cavity structure (1-1) comprises A horizontal cavity (A1), wherein the surfaces of the horizontal cavity (A1) are sequentially provided with A1 st vertical cavity, A2 nd vertical cavity, … th vertical cavity and an n-th vertical cavity which are communicated with the horizontal cavity (A1) at equal intervals in the direction from the left end to the right end; the 1 st vertical cavity and the n vertical cavity are edge cavities, the 2 nd vertical cavity is …, and the n-1 st vertical cavity is a middle cavity; the width d1 of the edge cavity is half of the width d2 of the middle cavity; the heights of the edge cavity and the middle cavity are the same;
A separation plugboard (1-3) is vertically arranged in the center of each middle cavity; the bottom of the separation plugboard (1-3) extends to the bottom of the horizontal cavity (A1); the top of the separation plugboard (1-3) and the top of the middle cavity are provided with a certain gap, and the gap is further adjusted by adjusting the height of the separation plugboard (1-3), and the height of the gap is adjusted according to the wavelength of the absorbed sound wave; therefore, the center of the 2 nd vertical cavity is provided with the 2 nd separation plugboard, the center of the 3 rd vertical cavity is provided with the 3 rd separation plugboard, …, and the center of the n-1 th vertical cavity is provided with the n-1 th separation plugboard; inside the rigid cavity structure (1-1), forming a tortuous cavity channel by arranging each separation plugboard (1-3) so as to enable the inner cavity of the rigid cavity structure (1-1);
The right side of the 2 nd vertical cavity is provided with a2 nd horizontal bulge communicated with the 2 nd vertical cavity; the right side of the 3 rd vertical cavity is provided with a 3 rd horizontal protrusion communicated with the 3 rd vertical cavity; and the right side of the nth vertical cavity is provided with an nth horizontal protrusion communicated with the nth vertical cavity; the surface phase of the composite sound absorption super-structure unit (1) is adjusted by setting the length of the 2 nd horizontal bulge, the thickness of the 2 nd horizontal bulge and the height of the setting position of the 2 nd horizontal bulge, the length of the 3 rd horizontal bulge, the thickness of the 3 rd horizontal bulge and the height of the setting position of the 3 rd horizontal bulge, …, the length of the nth horizontal bulge, the thickness of the nth horizontal bulge and the height of the setting position of the nth horizontal bulge; wherein, the height of the setting position of each horizontal bulge refers to the distance between the horizontal bulge and the bottom surface of the rigid cavity structure (1-1);
The spacing space between the 1 st vertical cavity and the 2 nd vertical cavity forms a1 st porous foam material embedded cavity;
the spacing space between the 2 nd vertical cavity and the 3 rd vertical cavity forms a 2 nd porous foam material embedded cavity;
…
the n-1 th vertical cavity and the interval space between the n-1 th vertical cavities form an n-1 th porous foam material embedded cavity;
The 1 st porous foam material is embedded into the cavity, the 2 nd porous foam material is embedded into the cavity, … th porous foam material is embedded into the cavity, and the n-1 st porous foam material is respectively embedded into the porous foam materials.
2. A composite sound absorbing super-structure surface based on porous material according to claim 1, characterized in that each composite sound absorbing super-structure unit (1) comprises n-1 composite structure subunits;
Wherein:
A1 st composite structure subunit is formed between the left side of the 1 st vertical cavity and the 2 nd separation plugboard;
A2 nd composite structure subunit is formed between the left side of the 2 nd vertical cavity and the 3 rd separation plugboard;
an n-1 composite structure subunit is formed between the n-1 separation plugboard and the right side of the n vertical cavity.
3. A composite sound absorbing super-structure surface based on porous material according to claim 2, characterized in that each composite sound absorbing super-structure unit (1) comprises 4 or 8 composite structure subunits.
4. The composite sound absorption super-structure surface based on the porous material according to claim 2, wherein the length L3, the thickness H2 and the setting position height H3 of the horizontal protrusion of each composite structure subunit are selected according to the vibration displacement response of the composite structure subunit, and the phase of the reflected sound wave is regulated and controlled within the range of 0-2 pi.
5. The composite sound absorbing super-structure surface based on porous material as claimed in claim 4, wherein the length of each composite structural subunit is equal, and is L2, and the height is H1;
Then:
the length l3= (0-0.5) L2 of the horizontal protrusion of each composite structural subunit; thickness h2= (0-0.1) H1 of the horizontal protrusion; the setting position height h3= (0-1) H1 of the horizontal protrusion.
6. The porous material-based composite sound absorption super-structured surface of claim 5, wherein when n=5, the 2 nd vertical cavity, the 3 rd vertical cavity, the 4 th vertical cavity and the 5 th vertical cavity are respectively provided with horizontal protrusions by:
The horizontal protrusions of the 2 nd vertical cavity have the following parameters: l3= (0.2-0.4) L2; h3 = (0.6-0.7) H1; h2 = (0-0.1) H1;
The horizontal protrusions of the 3 rd vertical cavity set have the following parameters: l3=0; h3 =0, h2=0, i.e.: no horizontal protrusions are arranged;
The horizontal protrusions of the 4 th vertical cavity have the following parameters: l3= (0.2-0.4) L2; h3 =h1; h2 = (0-0.1) H1;
The horizontal protrusions of the 5 th vertical cavity have the following parameters: l3= (0.2-0.4) L2; h3 =h1; h2 = (0 to 0.1) H1.
7. A composite sound absorbing super structure surface based on porous material according to claim 1, wherein the width d1= (0-0.2) L2 of the edge cavities of each composite structural subunit.
8. A composite sound absorbing super structure surface based on porous material as claimed in claim 1, wherein the height of the separating insert plate of each composite structural subunit is H4; h4 = (0.5-0.99) H1.
9. A composite sound absorbing super-structured surface based on porous material according to claim 1, characterized in that the porous foam material (1-2) is melamine foam or metal foam;
the length L2 of each composite structure subunit is 10-30 mm, and the height H1 is 20-50 mm; the wall thickness of the cavity wall of the rigid cavity structure (1-1) is 0.3-3 mm; the thickness of the separation plugboard (1-3) is 1-10 mm.
10. The composite sound absorption super-structure surface based on the porous material according to claim 1, wherein the top surface of the 1 st vertical cavity is a cavity channel inlet, a microperforated plate (1-4) is arranged on the top surface of the 1 st vertical cavity, and the thickness of the microperforated plate (1-4) is the same as the thickness of the outer wall surface of the rigid cavity structure (1-1);
The micro-perforated plate (1-4) is provided with a plurality of micro through holes (1-4-1); the micro through holes (1-4-1) are uniformly distributed in a regular manner; the number and the diameter of the micro through holes (1-4-1) are selected according to the foam porosity and the surface impedance requirement of the composite sound absorption super-structure surface of the porous material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210106593.4A CN114242027B (en) | 2022-01-28 | 2022-01-28 | Composite sound absorption super-structured surface based on porous material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210106593.4A CN114242027B (en) | 2022-01-28 | 2022-01-28 | Composite sound absorption super-structured surface based on porous material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114242027A CN114242027A (en) | 2022-03-25 |
| CN114242027B true CN114242027B (en) | 2024-04-16 |
Family
ID=80747423
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210106593.4A Active CN114242027B (en) | 2022-01-28 | 2022-01-28 | Composite sound absorption super-structured surface based on porous material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114242027B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104464711A (en) * | 2014-12-08 | 2015-03-25 | 大连理工大学 | Low-frequency broadband sound-absorbing device with sound-absorbing material units in weakly elastic cascade connection as periodic structure design layers |
| CN112951191A (en) * | 2021-02-22 | 2021-06-11 | 长春理工大学 | Low-frequency broadband sound absorption composite structure and preparation method thereof |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9607598B2 (en) * | 2015-08-17 | 2017-03-28 | The Boeing Company | Acoustic sandwich panel and method |
| US11862136B2 (en) * | 2016-04-19 | 2024-01-02 | Component Technologies, L.L.C. | Acoustic metamaterial units with the function of soundproof, flow passing and heat; transfer enhancement, the composite structure and the preparation methods thereof |
-
2022
- 2022-01-28 CN CN202210106593.4A patent/CN114242027B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104464711A (en) * | 2014-12-08 | 2015-03-25 | 大连理工大学 | Low-frequency broadband sound-absorbing device with sound-absorbing material units in weakly elastic cascade connection as periodic structure design layers |
| CN112951191A (en) * | 2021-02-22 | 2021-06-11 | 长春理工大学 | Low-frequency broadband sound absorption composite structure and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| 基于微孔板与折曲通道的亚波长宽带吸声结构设计;吴飞;黄威;陈文渊;肖勇;郁殿龙;温激鸿;;物理学报;20200708(第13期);全文 * |
| 新型阻抗复合吸声材料设计研究;刘鹏;周兵;陈兴旺;王延召;袁文超;王佩华;;环境科学与技术;20171215(第S2期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114242027A (en) | 2022-03-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Zarastvand et al. | Acoustic insulation characteristics of shell structures: a review | |
| JP6970880B2 (en) | Acoustic metamaterials Equipment in noise control methods and duct systems | |
| Legault et al. | Sound transmission through a double panel structure periodically coupled with vibration insulators | |
| Tang et al. | Sound absorption of micro-perforated sandwich panel with honeycomb-corrugation hybrid core at high temperatures | |
| Huang et al. | Sound-absorbing materials | |
| Wang et al. | Sound transmission through a sandwich structure with two-layered pyramidal core and cavity absorption | |
| CN109754776B (en) | Low-frequency broadband sound absorption covering layer embedded with cylindrical cavity array | |
| Yang et al. | Development of a novel porous laminated composite material for high sound absorption | |
| Magliacano et al. | Numerical investigations about the sound transmission loss of a fuselage panel section with embedded periodic foams | |
| Zhou et al. | Optimization design of acoustic performance of underwater anechoic coatings | |
| Kone et al. | Multi-tonal low frequency noise control using Helmholtz resonators with complex cavity designs for aircraft cabin noise improvement | |
| Li et al. | Sound transmission through metamaterial-based double-panel structures with poroelastic cores | |
| CN113216025B (en) | Road sound barrier noise reduction device and structural design method thereof | |
| Ma et al. | Passive acoustic liners for aero-engine noise control: A review | |
| CN114242027B (en) | Composite sound absorption super-structured surface based on porous material | |
| CN112992113B (en) | Light and thin composite sound insulation structure based on acoustic super-surface and sound insulation method | |
| Cummings et al. | Finite element computation of attenuation in bar-silencers and comparison with measured data | |
| CN113002695B (en) | Underwater sandwich sound insulation structure based on foam super-structure surface | |
| CN214741561U (en) | Sound attenuation structure, muffler and unmanned aerial vehicle based on super material of acoustics | |
| Golzari et al. | Sound transmission through truncated conical shells | |
| Yan et al. | Broaden the sound absorption band by using micro-perforated plate back cavities with different cross-sectional areas | |
| Huang | A theoretical study of passive control of duct noise using panels of varying compliance | |
| Liu et al. | Analysis of an ultra-low frequency and ultra-broadband phononic crystals silencer with small size | |
| Qu et al. | Sound reflection of acoustic porous metasurfaces under uniform mean flow | |
| Yang et al. | Characteristics and calculation method of sound radiation of cylindrical shell with porous sound-absorbing material under acoustic excitation |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |