CN111120766B - Detachable metal sintering silk screen noise reduction device - Google Patents
Detachable metal sintering silk screen noise reduction device Download PDFInfo
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- CN111120766B CN111120766B CN201911193651.6A CN201911193651A CN111120766B CN 111120766 B CN111120766 B CN 111120766B CN 201911193651 A CN201911193651 A CN 201911193651A CN 111120766 B CN111120766 B CN 111120766B
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- 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
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Abstract
The invention discloses a detachable metal sintering wire mesh noise reduction device, which comprises a groined support frame arranged in a pipeline, a plurality of metal sintering wire mesh modules and a plurality of front pressing plates, wherein the front pressing plates are arranged on the groined support frame; the metal sintering wire mesh module comprises a front lattice frame, M layers of metal sintering wire meshes and a rear lattice frame; the front lattice frame is used for inhibiting back pressure impact deformation, and the rear lattice frame is used for inhibiting impact deformation in the airflow direction; the M layers of metal sintering silk screens are metal sintering silk screens which are laminated together in a laser sintering mode and are used for pneumatic noise reduction in a wide frequency domain; the frame strips are positioned between the front lattice frame and the back lattice frame, are opposite in position and are fixed together; the front pressing plates fix the metal sintering wire mesh modules on the # -shaped supporting frame through screws; the periphery of the metal sintering wire mesh module is processed into concave-convex structures with different structures, and the concave-convex structures can be connected in a concave-convex mode to reduce the blocking ratio of the # -shaped frame. The invention has reasonable and simple structure, convenient disassembly and assembly, wide noise reduction frequency band and can bear larger impact load.
Description
Technical Field
The invention relates to a detachable metal sintering wire mesh noise reduction device, which is a noise reduction device applied to flowing gas in a pipeline and belongs to the field of experimental aerodynamics.
Background
The high-quality flow field of the wind tunnel requires low noise and low turbulence. The noise reducing method for the temporary-flushing high-speed wind tunnel pressure regulating valve mainly comprises a mesh-laying multilayer pore plate and a resonant cavity type sheet silencer. The noise reduction of the mesh-laying multi-layer pore plate is not obvious, and the mesh-laying multi-layer pore plate mainly depends on a resonant cavity type sheet silencer. The plate type silencer has small pressure loss and good silencing effect for medium and high frequency bands of about 4000 Hz. But the structure blockage ratio is large, the occupied space is large, regenerative noise exists, the high-speed noise reduction effect is weakened, the low-frequency noise elimination quantity is small, and the like. And the resonant cavity type sheet silencer is installed at one time, the noise reduction effect is reduced after long-term use, the later maintenance is usually required to be stopped, the production is removed and the maintenance is difficult, and the maintenance cost is huge for a large-size wind tunnel.
Disclosure of Invention
The technical problems solved by the invention are as follows: the detachable metal sintering wire mesh noise reduction device applied to the high-speed wind tunnel pipeline is provided, and has stronger noise reduction capability in a full frequency band range; through unsmooth concatenation between a plurality of metal sintering silk screen modules, for direct concatenation, the reduction structure jam ratio.
The technical solution of the invention is as follows: a detachable metal sintering wire mesh noise reduction device comprises a groined support frame and N metal sintering wire mesh modules, wherein N is the number of grids in the groined support frame;
the metal sintering wire mesh module comprises a front lattice frame, M layers of metal sintering wire meshes and a rear lattice frame, wherein M is more than or equal to 1; the front lattice frame is used for inhibiting back pressure impact deformation, and the rear lattice frame is used for inhibiting impact deformation in the airflow direction; m layers of metal sintering silk screen layers are overlapped together and positioned between the front grid frame and the rear grid frame for pneumatic noise reduction in a wide frequency domain, and the frame strips of the front grid frame and the rear grid frame are opposite in position and fixed together; the metal sintering wire mesh module is made into a module which can be independently installed and detached, and is installed and fixed on the # -shaped supporting frame through a body, and the # -shaped supporting frame is fixedly installed on the cross section of the pipeline.
The groined support frame is formed by welding a plurality of transverse strip plates and longitudinal strip plates after being spliced.
And the middle part of each inner wall in each grid of the # -shaped supporting frame is provided with a positioning block for positioning the metal sintering wire mesh module, so that the metal sintering wire mesh module is flush with the surface of the # -shaped supporting frame after being plugged into the corresponding grid of the # -shaped supporting frame.
The metal sintering silk screen is formed by sintering one or more layers of laser, and the mesh number is 40-160.
The periphery of the metal sintering wire mesh module is processed into concave-convex structures with different structures, and the concave-convex structures are connected with each other to reduce the blocking ratio of the # -shaped frame.
The metal sintering wire mesh is obtained by restoring the permeability through ultrasonic cleaning.
The wire diameter of the metal sintering wire mesh is 0.07mm-0.25 mm.
The device also comprises a front pressing plate, and the front pressing plate simultaneously fixes the plurality of metal sintering silk screen modules on the # -shaped supporting frame along the longitudinal or transverse frame of the # -shaped supporting frame through screws.
The front pressing plate, the groined support frame, the front lattice frame and the rear lattice frame are all made of metal materials.
A plurality of metal sintering wire mesh noise reduction devices can be arranged in the pipeline at certain intervals to realize graded noise reduction.
Compared with other technologies, the invention has the advantages that:
(1) according to the invention, the space in the pipeline is divided into N independent grids through the # -shaped frame, and the metal sintering wire mesh module is independently installed in each grid and used for rectifying in the pipeline to break large vortexes into tiny small vortexes, so that the uniformity of fluid can be greatly improved, and the turbulence degree of air flow in the pipeline is reduced. The effect is superior to that of a damping net structure.
(2) The metal sintering wire mesh is fixed by the screws through the front lattice frame and the rear lattice frame, so that the metal sintering wire mesh can bear larger impact load, and the structural strength and rigidity of the metal sintering wire mesh are good.
(3) The invention adopts the metal sintering wire mesh to reduce noise frequency bandwidth of flowing gas in the pipeline, has good noise reduction effect on the broadband of 0-40000Hz, optimizes the mesh number and the laying layer number of the sintering wire mesh, has large noise reduction range and reduces noise amount within 4dB-15 dB.
(4) Compared with a resonant cavity type sheet silencer, each metal sintering wire mesh module of the metal sintering wire mesh noise reduction device can be independently disassembled and assembled, and the permeability of the metal sintering wire mesh noise reduction device can reach 5.47 multiplied by 10 through ultrasonic cleaning-3L/(min·cm2Pa) can restore the original noise reduction capability, is convenient to disassemble and assemble, is easy to maintain, can be used for a long time, and reduces the cost;
(5) the invention has simple structure, convenient disassembly and maintenance and small occupied space. The ratio L/D of the structural length L to the pipeline diameter ratio D is always larger than 1, and the ratio L/D of the structural length L to the pipeline diameter ratio D can be controlled to be 0.25-0.8. For large wind tunnels and pipelines, the structure occupies small space and the construction cost is correspondingly reduced under the same noise reduction level.
(6) The peripheral frames of the metal sintering wire mesh module can be designed and processed into concave-convex structures, are integrally installed through concave-convex splicing and are fixed on the # -shaped supporting frame through screws, and the blocking ratio of the # -shaped supporting frame is reduced by about 20% compared with that of the # -shaped supporting frame which is directly spliced in a straight line.
(8) The detachable metal sintering wire mesh noise reduction device provided by the invention can be installed on the ground in a modularized manner, so that the time for installing the detachable metal sintering wire mesh noise reduction device in a pipeline is shortened.
(9) The multi-channel metal sintering wire mesh noise reduction device provided by the invention can be arranged in the pipeline at certain intervals along the axial direction of the pipeline, so that graded noise reduction is realized.
Drawings
FIG. 1 is a general view of a detachable sintered wire mesh noise reducer according to an embodiment of the present invention;
FIG. 2(a) is a left side view of a detachable sintered wire mesh noise reducer according to an embodiment of the present invention;
FIG. 2(b) is an enlarged view of a detachable sintered wire mesh noise reducer A according to an embodiment of the present invention;
FIG. 3(a) is a top view of a modular construction of an embodiment of a wire sintering screen of the present invention;
FIG. 3(b) is a side view of a modular construction of a sintered wire mesh module according to an embodiment of the present invention;
FIG. 4(a) is a schematic diagram of a metal sintered wire mesh module without concave-convex splicing structure;
FIG. 4(b) is a schematic diagram of a rectangular concave-convex splicing structure of a sintered metal screen module according to an embodiment of the present invention;
FIG. 4(c) is a schematic diagram of a rectangular and trapezoidal concave-convex splicing structure of a sintered metal screen module according to an embodiment of the present invention;
fig. 5 is a detailed view of the fixing of the concave-convex splicing structure of the sintered metal screen module according to the embodiment of the present invention.
Detailed Description
The invention is described in further detail below with reference to the following figures and specific examples: the examples are not intended to limit the invention. Those skilled in the art will appreciate that those matters not described in detail in the present specification are well known in the art.
The sintered wire mesh modules with the mesh number of 80-160 meshes are arranged on the # -shaped frame through one or more layers, the mesh number and the laying layer number of the sintered wire mesh are optimized, the noise reduction is 4dB-15dB, the sintered wire mesh modules can be integrally disassembled, and the maintenance and the installation are convenient. The metal sintering wire mesh is integrally installed and fixed on the # -shaped supporting frame through concave-convex splicing, so that the structural blockage ratio can be reduced, and the structural blockage ratio is reduced by about 20%. The metal sintering wire mesh can be used for a long time after the permeability is restored by ultrasonic cleaning. The invention has reasonable and simple structure, convenient disassembly and assembly, wide noise reduction frequency band and can bear larger impact load.
As shown in fig. 1, 2(a) and 2(b), the sintered wire mesh noise reduction device includes a # -shaped support frame 2, N sintered wire mesh modules 4 and a front press plate 5, where N is the number of meshes in the # -shaped support frame 2;
the metal sintering wire mesh module 4 is made into a module which can be independently installed and detached, and is installed and fixed on a groined support frame through a body, and the groined support frame is fixedly installed on the cross section of the pipeline 1; the front pressing plate 5 fixes a plurality of metal sintering wire mesh modules 4 on the # -shaped supporting frame 2 simultaneously along the longitudinal or transverse frame of the # -shaped supporting frame 2 through screws, and then the whole pipeline is covered with the metal sintering wire mesh modules.
The groined support frame 2 is formed by welding a plurality of transverse strips and longitudinal strips after being spliced. The structural design of the # -shaped support frame 2 is determined by the mechanical properties of the sintered wire mesh and the maximum total pressure difference. Designing a supporting form and a structure of the sintering silk screen according to the characteristics of strength, rigidity and the like of the sintering silk screen; and determining the maximum load design frame structure according to the maximum pressure difference and the cross section area of the cross section.
The middle part of each inner wall in each grid of the # -shaped supporting frame 2 is provided with a positioning block 3 for positioning the metal sintering wire mesh module 4, so that the metal sintering wire mesh module 4 is flush with the surface of the # -shaped supporting frame 2 after being plugged into the corresponding grid of the # -shaped supporting frame 2.
As shown in fig. 3(a) and 3(b), the sintered wire mesh module 4 includes a front lattice frame 4-1, M layers of sintered wire mesh 4-2, and a rear lattice frame 4-3, M being equal to or greater than 1; the front lattice frame 4-1 is used for inhibiting back pressure impact deformation, and the rear lattice frame 4-3 is used for inhibiting impact deformation in the airflow direction; m layers of metal sintering silk screens 4-2 are laminated together and are positioned between the front grid frame 4-1 and the rear grid frame 4-3 for pneumatic noise reduction in a wide frequency domain, and the positions and the sizes of the frame strips of the front grid frame 4-1 and the rear grid frame 4-3 are in one-to-one correspondence and are fixed together. The front lattice frame 4-1 and the sintered wire mesh 4-2 are fixed to the rear lattice frame 4-3 by fixing screws 4-4.
The metal sintering wire mesh 4-2 is a sintering porous material, is made by overlapping a plurality of layers of metal wire meshes according to a certain process and sintering under vacuum, and has good permeability. The sintered structure generally includes a support layer, a working layer, and a protective layer. Can be one or more layers of sintered silk screen sintered by laser, and the mesh number is 40-160.
The excellent metal sintered wire mesh 4-2 has the following characteristics:
A. excellent permeability;
B. controllability of pore size and porosity;
C. the strength is high, and the toughness is good;
D. better regeneration performance;
E. better machinability.
The selection of the mesh number of the metal sintering wire mesh 4-2 and the layer number determines the noise reduction characteristic and the pressure loss characteristic according to the previous test. Determining the optimal value of the noise reduction/pressure loss of the whole flow speed interval according to a test; and selecting one or more groups for installation according to the noise reduction design requirement. The wire diameter of the used metal sintering wire mesh 4-2 is 0.07mm-0.25mm, and the wire warp deviation is strictly controlled to be less than or equal to 5%, so that the metal sintering wire mesh has better and consistent air permeability on the premise of ensuring enough strength. The noise reduction of each layer of metal sintered wire mesh 4-2 is about 4dB-15 dB.
When the noise reduction performance is reduced by 10%, the metal sintering wire mesh module 4 is removed from the # -shaped supporting frame 2, the metal sintering wire mesh 4-2 is placed in an ultrasonic cleaning machine for ultrasonic cleaning, and the permeability reaches 5.47 multiplied by 10-3L/(min·cm2Pa) can restore the original noise reduction capability, and is convenient to disassemble and assemble and easy to maintain;
when the structure of the # -shaped supporting frame 2 requires a small blocking ratio, the peripheries of the plurality of metal sintering wire mesh modules 4-2 can be processed into concave-convex structures of different patterns, and the concave-convex structures are spliced and integrally installed and fixed on the # -shaped supporting frame 2, so that the cross-sectional area of the screws fixed on the # -shaped supporting frame 4 is reduced, the blocking ratio of the whole device is reduced, and the blocking ratio of the # -shaped supporting frame is reduced by more than about 20% compared with that of the straight line splicing (figure 4 (a)). The rectangular concavo-convex structure is shown in fig. 4(b), and the trapezoidal concavo-convex structure is shown in fig. 4 (c). The fixing manner of the concave-convex splicing structure of the metal sintered wire mesh module is shown in fig. 5.
The front pressing plate 5, the # -shaped supporting frame 2, the front lattice frame 4-1 and the rear lattice frame 4-3 are all made of metal materials.
The invention relates to a detachable metal sintering wire mesh noise reduction device, which reduces the installation time in a pipeline through modularized ground installation, and solves the installation problem of a sintering wire mesh with a small processing size in a large pipeline through modularized and groined frame installation.
Based on the invention, a plurality of metal sintering wire mesh noise reduction devices can be arranged in the pipeline at certain intervals to realize graded noise reduction.
Those skilled in the art will appreciate that those matters not described in detail in the present specification are well known in the art.
Claims (7)
1. A detachable metal sintering wire mesh noise reduction device is characterized by comprising a groined support frame (2) and N metal sintering wire mesh modules (4), wherein N is the number of grids in the groined support frame (2);
the metal sintering wire mesh module (4) comprises a front lattice frame (4-1), M layers of metal sintering wire meshes (4-2) and a rear lattice frame (4-3), wherein M is more than or equal to 1; the front lattice frame (4-1) is used for inhibiting back pressure impact deformation, and the rear lattice frame (4-3) is used for inhibiting impact deformation in the airflow direction; m layers of metal sintering silk screens (4-2) are laminated together and positioned between the front grid frame (4-1) and the rear grid frame (4-3) for pneumatic noise reduction in a wide frequency domain, and the frame strips of the front grid frame (4-1) and the rear grid frame (4-3) are opposite in position and fixed together; the metal sintering wire mesh module is made into a module which can be independently installed and detached, and is integrally installed and fixed on the # -shaped supporting frame through splicing, and the # -shaped supporting frame is fixedly installed on the cross section of the pipeline (1); the groined support frame (2) is formed by splicing and welding a plurality of transverse strip plates and longitudinal strip plates; a positioning block (3) is arranged in the middle of each inner wall in each grid of the # -shaped supporting frame (2) and used for positioning the metal sintering wire mesh module (4), so that the metal sintering wire mesh module (4) is flush with the surface of the # -shaped supporting frame (2) after being plugged into the corresponding grid of the # -shaped supporting frame (2); the periphery of the metal sintering wire mesh module is processed into concave-convex structures with different structures, and the concave-convex structures are connected with each other to reduce the blocking ratio of the # -shaped frame.
2. A removable sintered wire mesh noise reducer according to claim 1, wherein said sintered wire mesh (4-2) is one or more layers of sintered wire mesh made by laser sintering, with a mesh size of 40-160.
3. A demountable sintered metal mesh noise reducer according to claim 1, wherein said sintered metal mesh (4-2) is a sintered mesh with restored permeability by ultrasonic cleaning.
4. A demountable sintered wire mesh noise reduction device according to claim 1, wherein the wire diameter of said sintered wire mesh (4-2) is 0.07mm-0.25 mm.
5. A removable sintered wire mesh noise reduction device according to claim 1, characterized by further comprising a front pressing plate (5), the front pressing plate (5) simultaneously fixing a plurality of sintered wire mesh modules (4) on the # -shaped supporting frame (2) along the longitudinal or transversal frame of the # -shaped supporting frame (2) by means of screws.
6. A demountable sintered wire mesh noise reducer according to claim 1, wherein the front press plate (5), the cross-shaped support frame (2), the front lattice frame (4-1), and the rear lattice frame (4-3) are made of metal materials.
7. The detachable sintered metal mesh noise reducer of claim 1, wherein a plurality of sintered metal mesh noise reducers are arranged in the pipeline at intervals to achieve graded noise reduction.
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| CN114813096B (en) * | 2022-06-29 | 2022-09-06 | 中国空气动力研究与发展中心超高速空气动力研究所 | Multi-layer sintering net test model selection method for hypersonic wind tunnel |
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| JPH1061342A (en) * | 1996-08-15 | 1998-03-03 | Yamaha Corp | Soundproof door |
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| CN2380992Y (en) * | 1999-07-27 | 2000-05-31 | 安泰科技股份有限公司 | Sound-absorbing noise-reducing net apparatus |
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