KR100555375B1 - Resonance type duct silencer - Google Patents

Abstract

The present invention relates to a resonance type duct silencer, which is connected to the duct and the hollow body is formed in the inlet and the discharge port at both ends so that the sound propagates with the fluid flowing, and is hypothesized along the side wall inside the body to form a flow path And a splitter made of a steel plate having an inner space formed by a planar portion punched between the curved portion having both sides and the curved portion having a predetermined curvature at both ends, wherein the splitter is parallel to the inner sidewall of the body. A steel plate forming an internal resonance space to be arranged, a first diaphragm perpendicular to the plane portion of the steel plate, dividing the internal resonance space into a plurality of parts, and a resonance space divided by the first diaphragm at a predetermined ratio; It consists of a plurality of second diaphragm partitioning and the steel plate is partitioned by a second diaphragm in the flat portion When the thickness is in the range of 0.4 to 2 mm so as to open the side resonance space, the diameter of 0.1 to 5 mm, the opening ratio to the area is selectively partially drilled in the range of 3 to 30%, and the second diaphragm is formed by the steel plate and When the thickness is in the range of 0.4 to 2mm so that the closed spaces can communicate with each other, the noise incident on the perforated plate is formed by selectively drilling in the range of 0.1 to 4mm in diameter and 0.1 to 5% of the opening ratio to the area. It has a strong resonance between and the resonance space. This resonance effect is accompanied by strong nonlinear phenomena as the sound waves pass through the perforations of the perforated plate, dissipating the sound energy into thermal energy, providing a resonance type duct silencer that effectively reduces the noise propagating into the duct without sound absorbing material. do.

Duct, Silencer, Cavity, Perforated Plate

Description

Resonance Duct Silencer {RESONANCE TYPE DUCT SILENCER}

1 is a perspective view showing a first embodiment of a resonance duct silencer of the present invention.

2 is a cross-sectional view of FIG. 1.

3 is a cross-sectional view showing a second embodiment of the resonance type duct silencer of the present invention.

4 is a sectional view showing a third embodiment of the resonance type duct silencer of the present invention.

5 is a perspective view showing a fourth embodiment of the resonance type duct silencer of the present invention.

6 is a perspective view showing a fifth embodiment of the resonance type duct silencer of the present invention.

7 is a side cross-sectional view of FIG. 6.

Figure 8 is a graph comparing the noise level of the resonance type duct silencer of the present invention and the duct silencer using the glass fiber of the prior art as a suction material.

** Description of the symbols for the main parts of the drawings **

1, 100, 200, 300, 400: Silencer 10, 410: Body

11, 411: inlet 12, 412: outlet

13: side wall 14: intermediate wall

20, 120, 220, 310, 320, 330, 340: splitter 21, 121, 221: steel sheet

22, 23, 122, 123, 222, 223: curved portion 24: flat portion

25, 125, 127, 225, 227, 229, 413: perforated 31, 131, 231, 431: first plate

32, 132, 232, 432: second plate 33, 133, 233, 433: perforated

124, 224: first flat portion 126, 226: second flat portion

228: third planar portion 420: splitter

The present invention relates to a resonance type duct silencer, and more particularly, to form a resonance volume of a predetermined volume and the perforated plate formed with a plurality of perforations causing strong resonance in the perforated plate and the resonant space to dissipate the noise without the sound absorbing material inside the duct It provides a resonance type duct silencer that can effectively reduce the noise propagated to.

In general, the duct is a passage and structure through which air or other fluids flow, and mainly serves as a pipe for moving air or gas in air-conditioning, air-conditioning and ventilation systems, and various industrial facilities. It is used a lot.

In this way, the duct serves as a passage for transmitting the noise generated from each element along with the transportation of the fluid, thereby installing a silencer for blocking noise at the entrance or the middle of the duct.

Sound-absorbing silencers are widely used to prevent noise in the duct or pipe as described above. Representative sound absorbing materials embedded in sound absorbing silencers include glass fiber and polyurethane foam. These sound absorbing materials are excellent in sound absorbing performance, but due to the characteristics of the material is severely limited in use. In other words, glass fiber is legally regulated in terms of environmental pollution due to scattering problems, and has a disadvantage in that durability and moisture resistance are weak. In addition, polyurethane foams are vulnerable to fire and are therefore prohibited from use in confined spaces for safety reasons.

Moreover, since glass fiber and polyurethane foam have excellent sound absorption performance in the medium and high frequency bands, there is a limit of application in suppressing low frequency noise generated in various rotary machines and combustors.

Therefore, the recent sound absorbing materials require various requirements such as flame retardancy, scattering suppression and durability depending on the application field as well as the sound absorbing performance, and as a alternative, a porous plate system composed of a porous plate and a resonance space has much interest. Is dragging.

The resonance type duct silencer of the present invention devised to solve such a problem is to absorb sound by dissipating sound waves by resonance of sound waves incident into the resonance space by forming a plurality of through-holes and a perforated plate formed in the resonance space. It can reduce noise even without

In addition, another feature of the present invention is to configure the perforated plate partitioning the resonant space different diameter and area perforated by differently perforated configuration so that it is possible to freely adjust the frequency bandwidth to reduce the noise.

Further, another feature of the present invention is to further improve the sound absorption performance by forming a plurality of rows of porous plates according to the degree and magnitude of noise, and by forming a plurality of layers of resonance spaces formed by the porous plates.

In addition, another feature of the present invention is to form a plurality of spaces vertically and horizontally formed through the perforated plate is formed differently to adjust the magnitude of the resonance may increase the efficiency of dissipation of noise and noise bandwidth is reduced To adjust.

In order to achieve the above object, the present invention is a hollow body in which the inlet and outlet are formed at both ends so that the sound propagates with the fluid flowing in connection with the duct, and is hypothesized along the side wall of the body to form a flow path And a splitter made of a steel plate having an inner space formed by a planar portion punched between the curved portion having both sides and the curved portion having a predetermined curvature at both ends, wherein the splitter is parallel to the inner sidewall of the body. A steel plate forming an internal resonance space to be arranged, a first diaphragm perpendicular to the plane portion of the steel plate, dividing the internal resonance space into a plurality of parts, and a resonance space divided by the first diaphragm at a predetermined ratio; It consists of a plurality of second diaphragm partitioning and the steel plate is partitioned by a second diaphragm in the flat portion When the thickness of the side resonance space is in the range of 0.4 to 2mm, the diameter of 0.1 to 5mm and the opening ratio to the area are selectively partially drilled in the range of 3 to 30%, and the second diaphragm is sealed with the space opened by the steel sheet. When the spaces are in the range of 0.4 to 2mm in thickness so as to communicate with each other, it is characterized in that it is configured to selectively perforate in the range of 0.1 to 4mm in diameter and 0.1 to 5% of the open ratio to the area.

In addition, the splitter is characterized in that a plurality of planes spaced apart from each other between the curved surface portions of the steel plate having a different width to form a plurality of layers of internal resonance space.

In addition, the splitter is characterized in that the resonance space of a plurality of layers formed by the planar portion of the steel sheet is partitioned into respective resonance spaces having different volumes by the first and second diaphragms extending.

In addition, the steel sheet is characterized in that the perforations formed in each of the planar portion is formed to have a different diameter and area to open ratio.

In addition, the second diaphragm is characterized in that the perforated to have a different diameter and area to open ratio.

In addition, the volume of the open space and the flow path by the flat portion of the steel sheet is characterized in that the larger than the volume of the closed space partitioned by the second diaphragm.

In addition, the splitter may be further hypothesized on both sides of at least one intermediate wall which is hypothesized side by side between both side walls of the body.

In addition, the splitter is characterized in that it is hypothesized along the outer peripheral surface of the cylindrical body.

Hereinafter, with reference to the accompanying drawings a preferred embodiment of the resonance type duct silencer of the present invention will be described.

1 is a perspective view showing a first embodiment of a resonance type duct silencer of the present invention, FIG. 2 is a plan sectional view of FIG. 1, and FIG. 3 shows a second embodiment of a resonance type duct silencer of the present invention. 4 is a cross-sectional view showing a third embodiment of the resonance type duct silencer of the present invention, FIG. 5 is a perspective view showing a fourth embodiment of the resonance type duct silencer of the present invention, and FIG. Is a perspective view showing a fifth embodiment of the resonant duct silencer of FIG. 7 is a side cross-sectional view of FIG. 6, and FIG. 8 is a duct silencer using the resonant duct silencer of the present invention and glass fiber of the prior art as a suction material. A graph comparing noise levels.

As shown in Figure 1 or 2, the configuration and operation effects of the resonance type duct silencer of the present invention according to the first embodiment are as follows.

Resonance type duct silencer (1) is a rectangular hollow body (10) and the inlet (11) and the discharge port (12) is formed at both ends so that the fluid flowing through the square duct is passed, and the interior of the body (10) A splitter 20 is provided along both sidewalls 13 to form a flow path therein and to attenuate and dissipate noise propagated with the fluid along the flow path.

The splitter 20 has curved portions 22 and 23 having a predetermined curvature so as to reduce flow resistance on the inlet 11 and the outlet 12 of the body 10, and the curved portion 22, 23 the steel plate 21 forming the side wall 13 and the cavity (Cavity) by the planar portion 24 connecting between them, and the internal resonance space is perpendicular to the plane portion 24 of the steel sheet 21 The first diaphragm 31 which divides into several pieces, and each 2nd diaphragm 32 which divides the resonance space divided by the said 1st diaphragm by a predetermined ratio again.

In the steel plate 21, a plurality of perforations 25 are partially formed in the flat part 24 so that one resonance space partitioned by the second diaphragm 32 is opened with the flow path. The perforations 25 are selectively formed in a range of 0.1 to 5 mm in diameter and 3 to 30% in open ratio to area when the thickness of the flat portion 24 is in the range of 0.4 to 2 mm.

 In addition, the second diaphragm 32 has a plurality of perforations 33 formed so that the flow path, the open space (hereinafter, the open space) and the closed space (hereinafter, the closed space) are communicated with each other by the steel plate 21. do. When the perforations 33 are in the range of 0.4 to 2 mm in thickness of the second diaphragm, they are selectively formed in a range of 0.1 to 4 mm in diameter and 0.1 to 5% in open area to area ratio.

Each of the open space and the closed space partitioned by the first diaphragm 31 and the second diaphragm 32 are formed to have different lengths to induce resonance of different frequency bands, and each of the open diaphragms has a second length. It is more effective to form the diaphragm 32 in between than the adjacent closed space.

Referring to the operation and effect of the resonance type duct silencer according to the first embodiment having such a configuration as follows.

Noise propagating with the fluid flowing through the inlet 11 of the body 10 connected to the duct enters into the open space through the perforation 25 formed in the flat portion 24 of the steel plate 21 of the splitter 20. The noise incident into the open space travels to the open space and the closed space through the perforation 33 formed in the second diaphragm 32, the volume of the resonance space, the perforation formed in the flat part 24, and the second. In the predetermined frequency band determined by the perforations 33 formed in the diaphragm 32 has a strong resonance action.

This resonance action is a strong non-linear phenomenon in the process of the noise is introduced into the open space and the closed space through the perforation 25 formed in the flat portion 24 of the steel plate 21 or the perforation 33 of the second diaphragm 32. Accompanied by dissipating the sound energy of noise as heat energy, it is possible to effectively reduce the noise propagating into the duct without using a sound absorbing material.

 In addition, the perforations 25 formed in the flat part 24 of the steel plate 21 and the perforations 33 formed in the second diaphragm 32 have different diameters and open area ratios relative to the total area. The frequency band of the noise can be adjusted freely.

In addition, each open space and a closed space partitioned by the first diaphragm 31 and the second diaphragm 32 have different volumes to reduce the frequency band determined by the volume of the resonance space. You can adjust the frequency band of the noise.

Therefore, the perforations 33 formed in the planar portion 24 and the second diaphragm 32 of the steel plate 21 and the respective resonance spaces partitioned by the first diaphragm 31 and the second diaphragm 32 are different from each other. By forming it, the noise of a low frequency band as well as a medium and high frequency band can be reduced effectively.

In addition, by forming the volume of the open space partitioned by the second diaphragm 32 larger than the volume of the sealed space, the noise propagated into the body 10 is formed in the flat portion 24 of the steel plate 21. (25) It is possible to increase the dissipation efficiency of the noise by making it better incident into the resonance space.

Hereinafter, the configuration and operation effects of the resonance type duct silencer according to the second embodiment shown in FIG. 3 will be described, and redundant description of the same parts as in the first embodiment will be avoided.

The resonance type duct silencer 100 is installed along both sidewalls 13 of the inside of the body 10, and the splitter 120 has a first flat portion 124 between both curved portions 122 and 123 of the steel plate 121. ) And the second planar portion 126 are arranged side by side, and each resonance space formed therein forms a layer, and the resonance space of each layer is again formed by the first diaphragm 131 and the second diaphragm 132. It is partitioned to have different volumes.

 As in the first embodiment, the first plane portion 124 and the second plane portion, as in the first embodiment, have a lower resonance space partitioned by the first diaphragm 131 and the second diaphragm 132, respectively. Partially drilled to achieve.

The second planar portion 126 may also perforate the front surface so that noise propagated with the flowing fluid is better incident into the resonance space of each layer.

In addition, the perforations 125 and 127 formed in the first planar portion 124 and the second planar portion 126 and the respective perforations 133 formed in the second diaphragm 132 are the same as in the first embodiment. Formed selectively in the range of conditions, the volume of each of the open space and the closed space partitioned by the first diaphragm and the second diaphragm may be formed differently.

By this configuration, the noise propagated into the body 10 is incident into the upper resonance space through a plurality of perforations 127 formed in the second planar portion 126 of the splitter 120.

The noise incident into the upper resonant space is dissipated by the strong resonance between the second diaphragm 132 and the upper closed space, and is incident into the lower open space through the perforations formed in the first plane.

In addition, the noise incident into the lower open space further reduces sound by dissipating negative energy by strong resonance between the second diaphragm and the lower closed space.

Therefore, the perforations 125 and 127 formed in the first and second planar portions 124 and 126 of the steel sheet and the perforations 133 formed in the second diaphragm 132 have various diameters and an open ratio with respect to the total area. In addition, by forming a variety of volumes of the open space and the enclosed space of each layer partitioned by the first diaphragm 131 and the second diaphragm 132, a wider medium and high frequency band as well as low frequency band noise Has the effect of dissipating.

As illustrated in FIG. 4, the configuration and operation effects of the resonance type duct silencer according to the third embodiment will be described. The splitter 220 may have different widths between the curved surfaces 222 and 223 of the steel plate 221. Three resonance spaces are formed in layers by the first, second, and third planar portions 224, 226, and 228, which are hypothesized, and the resonance spaces of each layer are formed by the first diaphragm 231 and the second diaphragm ( 232) is divided into a plurality of open spaces and closed spaces.

In addition, the perforations 225, 227, and 229 formed in the first, second, and third planar portions 224, 226, and 228 and the perforations 233 formed in the second diaphragm 232 are the same as in the first embodiment. It is optionally formed in the condition range.

In addition, the second or third planar portions 226 and 228 may also puncture the front surface of the second or third planar portion 226 and 228 so that noise is better incident into the resonance space of each layer as described in the second embodiment.

In addition, the description of the operation of the resonance type duct silencer according to the third embodiment is omitted because it overlaps with the description of the operation of the second embodiment except that the resonance space is added upward by the third plane portion 228. do.

As described above with reference to the second and third embodiments, the resonance spaces formed in the splitters 120 and 220 are not limited to two layers or three layers, and may be used as needed. By forming a large number of layers has the effect of reducing the noise of more various frequency bands.

As shown in FIG. Referring to the configuration and operation of the resonance type duct silencer according to the fourth embodiment, the splitter 310, 320, 330, 340 is formed along both side walls of the inside of the body 10 and between the side walls 13 It is additionally installed on both sides of the intermediate wall 14 arranged side by side to increase the noise reduction effect.

It is also possible to increase the number of splitters additionally arranged between both sidewalls 13 inside the body 10 in more rows, and furthermore, each splitter used further has already been described in the first to third embodiments. As described above, it is desirable to have resonant spaces of different layers, or to combine to have resonant spaces of different volumes so as to reduce noise in more various frequency bands.

As shown in FIG. 6 or FIG. 7, the resonance type duct silencer according to the fifth embodiment has a cylindrical body 410 which forms an internal flow path with both ends open for connection to a circular duct, and the body. The first diaphragm 431 and the first diaphragm 431 dividing the internal resonance space by vertically installing the resonance space on the outer circumferential surface of the body 410 and dividing the internal resonant space are formed on the outer circumferential surface of the body 410. It is composed of a splitter 420 consisting of a second diaphragm 432 to divide the resonant space partitioned by the partition again.

The body 410 has a plurality of perforations 413 formed in a predetermined section so that one side resonance space divided by the second diaphragm 432 is opened, and the second diaphragm 432 is formed on the body 410. As a result, a plurality of perforations 433 are formed so that the flow path, the open space and the closed space communicate with each other.

In addition, the perforations 413 formed on the body 410 and the perforations 433 formed on the second diaphragm 432 are respectively planar portions 24 of the steel plate 21 described in the first embodiment; The perforations 25 and 33 formed in the second diaphragm 32 are selectively formed within the same condition range.

Description of the operation of the resonance-type duct silencer 400 according to the fifth embodiment is omitted because it is overlapped with that described in the first embodiment except that the splitter 420 is formed along the outer circumferential surface of the cylindrical body 410. do.

In addition, the splitter 420, although not shown in the drawing, as described above, to have resonant spaces of different layers, or to be combined to have resonant spaces of different volumes to reduce noise of various frequency bands. It is natural.

As shown in FIG. 8, in order to compare the performance of the resonance type duct silencer according to the first embodiment of the present invention and the duct silencer using the conventional glass fiber as a sound absorbing material, the Seoul National University Noise and Vibration Research Center (Gongneung 2, Nowon-gu, Seoul) The material).

As a result of the evaluation, the resonance type duct silencer of the present invention has the same noise reduction effect in the high frequency band of 1 kHz or more based on 1 kHz compared to the duct silencer using glass fiber as a sound absorbing material, but more excellent in the low frequency band of 1 kHz or less. You can see the effect.

The resonance type duct silencer of the present invention devised to solve such a problem forms a resonance volume of a predetermined volume and a porous plate having a plurality of through-holes, so that the noise incident into the resonance space is dissipated by the resonance action, without the sound absorbing material. It has an effect that can reduce.

In addition, another feature of the present invention has the effect of freely adjusting the frequency band of the noise to be reduced by configuring the perforated plate partitioning the resonant space different diameter and area perforated different configuration.

In addition, another feature of the present invention has the effect of improving the noise reduction effect by forming a plurality of layers of the perforated plate according to the degree and magnitude of the noise, and to form a plurality of layers of the resonance space formed by the perforated plate.

In addition, another feature of the present invention is to form a plurality of spaces formed vertically and horizontally so that the space between the perforated plate to be different to adjust the dissipated frequency band to effectively reduce the noise of the low and high frequency bands as well Can be reduced.

Claims (8)

A hollow body having suction and discharge ports formed at both ends thereof so that sound propagates with the fluid flowing in connection with the duct; A splitter made of a steel plate that is constructed along sidewalls of the body to form a flow path, and an inner space is formed by a planar portion that is perforated between curved surfaces having both ends and a curved surface having both ends; In the duct silencer to include, The splitter includes: a steel plate forming an internal resonance space arranged in parallel with an inner sidewall of the body; a first plate vertically installed on a flat portion of the steel plate to divide the internal resonance space into a plurality; When the steel plate is composed of a plurality of second diaphragms that divide and divide the divided resonance spaces again at a predetermined ratio, and the steel sheet has a thickness in the range of 0.4 to 2 mm so that one side resonance space partitioned by the second diaphragm is opened in the plane portion, When the diameter of 0.1 to 5 mm, the opening ratio to the area is selectively partially drilled in the range of 3 to 30%, and the second diaphragm is in the range of 0.4 to 2 mm in thickness so that the space opened by the steel plate and the sealed space pass through each other, Resonance type duct silencer, characterized in that configured to be selectively drilled in the range of 0.1 to 4mm in diameter and 0.1 to 5% of the opening ratio to the area. The method of claim 1, The splitter is a resonance type duct silencer, characterized in that a plurality of planes spaced apart from each other between the curved surface portions of the steel plate having a different width to form an internal resonance space of a plurality of layers. The method of claim 2, The splitter is a resonance type duct silencer, characterized in that the plural layers of resonance spaces formed by the planar portion of the steel sheet is divided into respective resonance spaces having different volumes by the first diaphragm and the second diaphragm. The method of claim 2 or 3, The steel sheet is a resonance type duct silencer, characterized in that the perforations formed in each of the plane portion is formed to have a different diameter and area ratio. The method according to any one of claims 1 to 3, The second diaphragm is a resonance type duct silencer, characterized in that the perforated to have a different diameter and area to open ratio. The method according to any one of claims 1 to 3, And a volume of the passageway and the space opened by the planar portion of the steel sheet is larger than the volume of the enclosed space partitioned by the second diaphragm. The method according to any one of claims 1 to 3, And the splitter is further hypothesized on both sides of at least one of the intermediate walls which are arranged side by side between both side walls of the body. The method according to any one of claims 1 to 3, The splitter is a resonance type duct silencer, characterized in that it is hypothesized along the outer peripheral surface of the cylindrical body

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