CN115930001A - Blade type metamaterial pipeline for vibration and noise reduction - Google Patents
Blade type metamaterial pipeline for vibration and noise reduction Download PDFInfo
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- CN115930001A CN115930001A CN202211359892.5A CN202211359892A CN115930001A CN 115930001 A CN115930001 A CN 115930001A CN 202211359892 A CN202211359892 A CN 202211359892A CN 115930001 A CN115930001 A CN 115930001A
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- 230000009467 reduction Effects 0.000 title claims abstract description 27
- 229920001971 elastomer Polymers 0.000 claims abstract description 20
- 238000000034 method Methods 0.000 claims description 7
- 238000013016 damping Methods 0.000 claims description 6
- 239000000463 material Substances 0.000 claims description 5
- 229910000746 Structural steel Inorganic materials 0.000 claims description 3
- 239000006163 transport media Substances 0.000 claims 1
- 230000000737 periodic effect Effects 0.000 description 15
- 238000002955 isolation Methods 0.000 description 11
- 230000000694 effects Effects 0.000 description 8
- 238000013461 design Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 238000004088 simulation Methods 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 4
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- 230000006870 function Effects 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000006872 improvement Effects 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 244000043261 Hevea brasiliensis Species 0.000 description 1
- 230000009471 action Effects 0.000 description 1
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- 239000013078 crystal Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000012067 mathematical method Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 229920003052 natural elastomer Polymers 0.000 description 1
- 229920001194 natural rubber Polymers 0.000 description 1
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- 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
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Abstract
The invention discloses a blade type metamaterial pipeline for vibration and noise reduction, and belongs to the technical field of artificial elastic wave metamaterial. The pipeline comprises an inner cylinder, an outer cylinder, a circular ring, a rotary blade and filling rubber; the inner cylinder and the outer cylinder are arranged concentrically, the rings are distributed between the inner cylinder and the outer cylinder at equal intervals along the axial direction, the inner ring of each ring is connected with the outer circumferential surface of the inner cylinder, the outer circumferential surface of each ring is connected with the inner circumferential surface of the outer cylinder, the annular area between the inner cylinder and the outer cylinder is divided into independent and closed annular cavities by the two adjacent rings, the rotary blades are fixedly connected between the two rings and distributed along the circumferential direction, and the gaps formed by the rotary blades in the annular cavities are filled with filling rubber. The invention realizes the purposes of vibration reduction and noise reduction in a specific working frequency domain range and can provide enough bearing capacity.
Description
Technical Field
The invention belongs to the technical field of artificial elastic wave metamaterial, and particularly relates to a blade type metamaterial pipeline structure with internal fluid pressure for vibration and noise reduction.
Background
With the development of science and technology and the improvement of human living standard, the pipeline transportation becomes an important transportation mode due to the large use of pumps, and the negative effects brought by flow-induced vibration and noise in the process of conveying media by the pipeline are important factors influencing the transportation stability. Therefore, a pipeline structure with low vibration and low noise in the conveying process and certain bearing capacity is needed to solve the technical problem of pipeline conveying.
The periodic structure design is a structural design method with vibration and noise reduction functions, which tends to be perfect day by day, from 20 th century and 90 th era research to the present of mature theoretical and practical engineering application backgrounds. The frequency band gap characteristic can be generated through the design of the periodic structure, and the transmission characteristic of the elastic wave is blocked in the frequency forbidden band of the periodic structure, so that the vibration reduction and noise reduction functions of the structure are formed. And compared with the traditional damping vibration isolation method, the artificial periodic structure can meet the vibration and noise reduction function and simultaneously has bearing performance, so that the design of the vibration and noise reduction structure has guiding significance.
Disclosure of Invention
In view of this, the invention provides a blade type metamaterial pipeline for vibration damping and noise reduction, which achieves the purpose of vibration damping and noise reduction in a specific working frequency range and can provide sufficient bearing capacity.
A blade type metamaterial pipeline for vibration and noise reduction comprises an inner cylinder, an outer cylinder, a circular ring, a rotary blade and filling rubber;
the inner cylinder and the outer cylinder are concentrically arranged, the rings are distributed between the inner cylinder and the outer cylinder at equal intervals along the axial direction, the inner ring of each ring is connected with the outer circumference of the inner cylinder, the outer circumference of each ring is connected with the inner circumference of the outer cylinder, the annular area between the inner cylinder and the outer cylinder is divided into independent and closed annular cavities by the two adjacent rings, the n rotary blades are fixedly connected between the two rings and distributed along the circumferential direction, the filling rubber fills the gaps formed by the rotary blades in the annular cavities, the two rings and the n rotary blades between the two rings form a single cell, and the number of the single cells is m.
Further, the number m of the unit cells and the number n of the rotating blades take the values as follows: n is more than or equal to 8, m is more than or equal to 4.
Furthermore, the inner diameter D of the inner cylinder is more than or equal to 100mm, the outer diameter of the outer cylinder is D, wherein D-D is more than or equal to 10mm and more than or equal to 30mm.
Furthermore, the rotating blade has a torsion angle in the length direction of the pipeline, the torsion angle is theta, the thickness is h, and the rotating blade is positioned between the two circular rings and forms a circle with the circular rings
Angle setting angle mounting, setting angle>
Is the degree of an included angle between a tangent line of a middle surface of the rotary blade and the vertical direction of the circular ring.
Furthermore, the value range of the torsion angle theta is between 5 and 45 degrees, the value range of the thickness h is between 1 and 5mm, and the installation angle is
The value range of (a) is between 10 and 45 degrees.
Further, the inner cylinder is used for conveying a medium.
Furthermore, the rubber is soft rubber, and is sealed in a gap of the circular ring sleeved blade structure by a pouring method.
Further, the circular ring, the rotary blade, the inner cylinder and the outer cylinder are all made of common structural steel.
Has the advantages that:
1. the circular rings are arranged between the inner cylinder and the outer cylinder and are distributed at equal intervals along the axial direction, the rotary blades are connected between the circular rings, an artificial periodic metamaterial structure is formed, the structure can inhibit the propagation of axial elastic waves in a specific frequency domain, the pipeline can be used for the actual engineering requirements of vibration isolation and noise reduction of the specific frequency domain, and a pipeline selection for vibration isolation and noise reduction is provided for the working condition.
2. The values of the number m of single cells and the number n of rotating blades in the pipeline are as follows: n is more than or equal to 8, m is more than or equal to 4, and the obvious vibration reduction effect of the artificial periodic structure can be achieved.
3. The rotary blade of the invention has a torsion angle along the length direction of the pipeline, the torsion angle is theta, the thickness is h, the rotary blade is positioned between two circular rings and forms a circle with the circular rings
The angle mounting can play the roles of connection, vibration reduction and support.
4. The value range of the torsion angle theta of the rotary blade is between 5 and 45 degrees, the value range of the thickness h is between 1 and 5mm, and the mounting angle
The value range of (1) is 10-45 degrees, the torsion angle theta converts the axial force into the action of torsion force, so that the vibration damping effect is achieved, and the rotary blade with the thickness of 1-5 mm has an obvious vibration isolation effect.
5. The pipeline is made of common structural steel and natural materials, is easy to purchase, assemble and process compared with other metamaterial structures, has slightly higher cost than the common pipeline, and has obvious vibration isolation and noise reduction effects.
Drawings
FIG. 1 is a drawing ofThe blade type metamaterial pipeline n =12,m =6, theta =30 degrees,
structure diagram when d =240mm, d =280mm, h = 1mm;
fig. 2 shows a blade type metamaterial pipeline n =12,m =6, theta =30 degrees,
section diagrams of unit cells at d =240mm, d =280mm, h = 1mm;
fig. 3 shows that the blade type metamaterial pipeline n =12,m =6, theta =30 degrees,
unit cell burst plot at d =240mm, d =280mm, h = 1mm;
fig. 4 shows a metamaterial pipeline n =12,m =6, θ =30 °,
a main body structure diagram when d =240mm, d =280mm, h = 1mm;
fig. 5 shows that the metamaterial pipeline n =12,m =6, θ =30 °,
d =240mm, d =280mm, h = 1mm;
FIG. 6 is a front section view of a rotary blade according to an embodiment of the present invention;
FIG. 7 is a design drawing of the tail end of the rotary blade according to the embodiment of the present invention
Fig. 8 is a model diagram of the rotating blade of the embodiment of the invention when θ =30 ° and h =1 mm;
fig. 9 shows a metamaterial pipeline n =12,m =6, θ =30 °,
a graph of the simulation result of the vibration response when d =240mm, D =280mm, h = 1mm;
FIG. 10 shows a metamaterial according to an embodiment of the present inventionPipeline n =12,m =6, θ =30 °,
graph of sound transmission loss simulation results when d =240mm, d =280mm, h = 1mm.
Wherein: 1-circular ring, 2-rotary blade, 3-filling rubber, 4-inner cylinder and 5-outer cylinder.
Detailed Description
The invention is described in detail below by way of example with reference to the accompanying drawings.
The invention provides a blade type metamaterial pipeline for vibration reduction and noise reduction, which comprises an inner cylinder 4, an outer cylinder 5, a ring 1, a rotary blade 2 and filling rubber 3, as shown in figure 1, wherein the outer cylinder 5 with one half of circumference is cut in a partial sectional mode in the figure so as to be convenient for seeing the internal structure of the pipeline.
The inner cylinder 4 and the outer cylinder 5 are concentrically arranged, seven circular rings 1 are distributed between the inner cylinder 4 and the outer cylinder 5 at equal intervals along the axial direction, the inner ring of each circular ring 1 is connected with the outer circumferential surface of the inner cylinder, the outer circumferential surface of each circular ring is connected with the inner circumferential surface of the outer cylinder, the annular area between the inner cylinder 4 and the outer cylinder 5 is divided into independent and closed annular cavities by the two adjacent circular rings 1, 12 rotary blades 2 are fixedly connected between the two circular rings 1, the rotary blades 2 are distributed along the circumferential direction, the filling rubber 3 fills the gaps formed in the annular cavities by the rotary blades 2, half of the pipeline areas corresponding to the outer cylinder in a splitting part is filled with rubber, and the other half of the pipeline areas are not filled with rubber. The two circular rings 1 and the 12 rotary blades between the two circular rings form a single cell, and the number of the single cells is six.
In the embodiment, the filling rubber 3 is made of natural rubber material and is filled in the cavity, so that the noise response is effectively inhibited.
Fig. 2 and 3 show a unit cell structure diagram, wherein n (12) rotary blades with a rotation angle theta (30 degrees) are respectively fixed between two circular rings to play a certain role in connection and support, and the rotation angle can effectively inhibit axial excitation response.
Fig. 4 is a schematic view of a main structure formed by only the ring and the blades after the inner cylinder 4, the outer cylinder 5 and the filling rubber are removed, and fig. 5 is a schematic view of a structure formed by filling the filling rubber into three-quarter of the ring-shaped area on the basis of fig. 4.
Fig. 6 and 7 are design drawings for designing the front section and the tail end of the rotary blade 2, respectively, the rotary blade 2 has a torsion angle in the length direction of the pipeline, the torsion angle is theta, the thickness h is in the range of 5-45 degrees, the value range of the torsion angle theta is in the range of 1-5 mm, and the appearance of the rotary blade after the design is completed is as shown in fig. 8.
The elastic wave metamaterial has a periodic arrangement structure along the axial direction, and each unit cell is filled with rubber and forms a sandwich structure with the rotary blade, so that an artificial periodic elastic wave metamaterial pipeline configuration is formed, and the elastic wave metamaterial has an inhibiting effect on the propagation of elastic waves in a specific frequency domain range according to the characteristics of the artificial periodic metamaterial structure. When the elastic wave propagates in the artificial periodic structure, the elastic wave in certain frequency ranges cannot propagate under the interaction of the internal components, and the corresponding frequency ranges are called forbidden bands; while elastic waves in other frequency ranges may propagate, the corresponding frequency range being referred to as a passband.
In the embodiment of the invention, the number of each unit cell circumferential blade is n, the rotation angles are theta, the aim is to achieve the vibration isolation effect within the frequency range required by the engineering background of the embodiment of the invention, and the common technicians in the field can calculate and select the size and the material according to the actual working condition requirement and a theoretical formula of a band gap mechanism. The adjustment method is that when the ring direction is reduced to a certain number of blades and the rotation angle is increased, the forbidden band moves to a low frequency domain, otherwise, the forbidden band moves to a high frequency domain.
The invention can reduce the elastic wave and vibration transmission performance in certain frequency range by utilizing the band gap characteristic of the artificial periodic structure, thereby achieving the aim of vibration isolation and noise reduction. The invention is a blade type metamaterial pipeline for vibration and noise reduction, and can provide a new idea for further developing periodic structures or phononic crystal elastic wave metamaterials.
According to n =12,m =6, θ =30 °,
the simulation results of COMSOL software when d =240mm, D =280mm, h =1mm, and the vibration response simulation result graph of FIG. 9 and the sound transmission loss simulation result graph of FIG. 10 show that the vibration isolation effect is achieved in a plurality of frequency domains around 200Hz, 500Hz, 650Hz and 1000 Hz.
In addition, the number of the rotary blades in the invention
Number m of axial cycles, thickness h of the rotating blade, angle of repose->
The angle of rotation θ, each parameter being adjustable within the ranges described in this specification. The person skilled in the art can realize the vibration isolation effect of the invention in a specific frequency domain by a simple mathematical method.
The invention adopts an artificial periodic metamaterial structure, the generated band gap is called as Bragg band gap based on Bragg scattering mechanism, the frequency position of the Bragg band gap is mainly controlled by Bragg condition, namely:
wherein a represents the lattice size of the artificial periodic structure; λ represents the elastic wave wavelength in the artificial periodic structure. The vibration isolation and noise reduction in a specific frequency range can be achieved by adjusting the rotation angle, the number of the rotating blades and the material filled with rubber as described above.
The pipeline configuration of the invention is not limited in placement direction, can meet the requirement of vibration isolation and noise reduction of the axial pipeline under the working condition, and has certain universality.
In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. A blade type metamaterial pipeline for vibration and noise reduction is characterized by comprising an inner cylinder, an outer cylinder, a circular ring, a rotary blade and filling rubber;
the inner cylinder and the outer cylinder are concentrically arranged, the rings are distributed between the inner cylinder and the outer cylinder at equal intervals along the axial direction, the inner ring of each ring is connected with the outer circumference of the inner cylinder, the outer circumference of each ring is connected with the inner circumference of the outer cylinder, the annular area between the inner cylinder and the outer cylinder is divided into independent and closed annular cavities by the two adjacent rings, the n rotary blades are fixedly connected between the two rings and distributed along the circumferential direction, the filling rubber fills the gaps formed by the rotary blades in the annular cavities, the two rings and the n rotary blades between the two rings form a single cell, and the number of the single cells is m.
2. The blade type metamaterial pipeline for damping vibration and reducing noise of claim 1 wherein the number m of unit cells and the number n of rotating blades are selected from the group consisting of: n is more than or equal to 8, m is more than or equal to 4.
3. The blade type metamaterial pipeline for reducing vibration and noise as claimed in claim 2, wherein the inner diameter D of the inner cylinder is more than or equal to 100mm, the outer diameter of the outer cylinder is D, wherein 10mm is more than or equal to D-D is more than or equal to 30mm.
4. The blade-type metamaterial pipeline for damping vibration and reducing noise of claim 3, wherein the rotary blade has a torsion angle in the length direction of the pipeline, the torsion angle is θ, the thickness is h, and the rotary blade is positioned between two rings and forms a circle with the rings
Is arranged at an angle of arrangement and the angle of arrangement is->
Is a square with the tangent line of the middle surface of the rotary blade perpendicular to the circular ringThe included angle between the two directions is degree.
5. The blade type metamaterial pipeline for reducing vibration and noise as claimed in claim 4, wherein the torsion angle θ is in a range of 5-45 °, the thickness h is in a range of 1-5 mm, and the lay angle is
The value range of (A) is between 10 and 45 degrees.
6. The blade type metamaterial tubing for vibration and noise reduction of claim 5 wherein the inner cylinder is used to transport media.
7. The blade type metamaterial pipeline for reducing vibration and noise as claimed in claim 6, wherein the rubber is soft rubber, and is sealed at the gap of the ring-sleeved blade structure by a pouring method.
8. The blade type metamaterial pipe for reducing vibration and noise as claimed in claim 6 or 7, wherein the material of the ring, the rotating blades, the inner cylinder and the outer cylinder is common structural steel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211359892.5A CN115930001A (en) | 2022-11-02 | 2022-11-02 | Blade type metamaterial pipeline for vibration and noise reduction |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211359892.5A CN115930001A (en) | 2022-11-02 | 2022-11-02 | Blade type metamaterial pipeline for vibration and noise reduction |
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| CN115930001A true CN115930001A (en) | 2023-04-07 |
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| CN202211359892.5A Pending CN115930001A (en) | 2022-11-02 | 2022-11-02 | Blade type metamaterial pipeline for vibration and noise reduction |
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Citations (13)
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|---|---|---|---|---|
| DE1924734A1 (en) * | 1968-05-15 | 1969-11-27 | Dunlop Co Ltd | Soundproofing element |
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| CN209604696U (en) * | 2019-03-15 | 2019-11-08 | 河北普尚管道科技有限公司 | A kind of Silencing tube material |
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2022
- 2022-11-02 CN CN202211359892.5A patent/CN115930001A/en active Pending
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