KR20060004748A - Silencer of absorption-resonance type - Google Patents

Abstract

The present invention relates to a high performance sound absorption resonance silencer, comprising: an internal combustion engine (power generation airflow), exhaust gas, and a reduced pressure rear end stage. A muffler used in steam safety valves and the like, with a simple structure, the purpose of the present invention is to have a sound attenuation performance that is effective in reducing frequency components in the low and mid range.

To this end, the present invention is arranged in the longitudinal direction in the passage through which the fluid (Steam, exhaust gas) passes so that a plurality of washers 121 is inserted in the inner surface space, so as to prevent scattering of the sound absorbing material 124 while reducing resonance sound. A perforated plate 122 having a plurality of perforations formed therein is formed while surrounding the outside of the washer 121, and an outer side of the perforated plate is provided with a sound absorbing material 124 that absorbs noise, and surrounds the outside of the sound absorbing material 124. Sound absorbing resonance silencer is characterized in that the finishing material is formed to include 125.

Washers, Perforated Plates, Sound Absorbers, Silencers

Description

Sound Absorption Type Silencer {Silencer of Absorption-Resonance type}             

1 is an overall configuration cross-sectional view of a conventional rectifier silencer.

2 is a cross-sectional view of a silencer used in a conventional boiler pipe and the like.

Figure 3 is a cross-sectional view of the overall configuration of the resonance silencer according to the present invention.

Figures 4a, 4b is a graph showing the noise level of the empty tube shown in Table 1 and the resonance type silencer results of the present invention.

Explanation of symbols on the main parts of the drawings

110: inner tube 121: washer

122: perforated plate 124: sound absorbing material

125: finish

The present invention relates to a sound-absorbing resonance silencer, and more particularly, is used in the outlet of the steam safety valve, the exhaust gas of the internal combustion engine (generator), the intake of the air compressor of the reduced pressure rear end, the discharge tube, and the like. The present invention relates to a sound-absorbing resonance silencer capable of reducing the structure, having strong structural bonding strength and tensile strength even when exposed to air, and having a short drainage time and improving sound absorption performance.

Conventionally, the silencer absorbs sound energy by sound absorbing materials such as glass fibers provided in the periphery of the flow path and in the flow path, thereby reducing noise and causing interference and reflection of sound waves by the resonator attached to the flow path and the rapid expansion of the cross section of the flow path. There is reactance type to reduce noise.

However, in the sound absorption type, the noise of the high frequency range can be reduced, but the noise of the low frequency range can not be efficiently absorbed. In the reactance type, the noise of the low frequency range can also be reduced, but there is a problem of requiring a large installation space. As the sound absorbing type and the reacting type are properly combined and used, the structure becomes complicated and there is a difficulty in manufacturing and installing.

1 is a conventional silencer, the rectifier silencer 10 is installed in the gas supply line to implement the rectified noise when decompression gas, is installed in the fluid supply line to provide the rectified noise during fluid decompression, A main body 15 having an inlet part 11 to which a supply side is connected, an outlet part 13 to which a fluid demanding side is connected, and a rectifying chamber 17 formed between the inlet part 11 and the outlet part 13. And a rectifying member 19 which is accommodated in the rectifying chamber 17 to apply resistance to the flow of the fluid flowing through the inlet 11, and concentric with the rectifying member 19 of the main body 15. It includes a sound absorbing tube 20 of the porous portion 21 is in contact with the inner wall.

In addition, as shown in Figure 2 is another silencer is formed a plurality of supports 41 on the outside of the inner tube 30, the outer noise prevention tube 42 is formed by being surrounded by a predetermined interval spaced apart by the support. .

The silencer as described above generally reduces the noise of 80 to 90 dB with a noise of 73 to 83 dB in the frequency band between 500 and 1,000 Hz, and generally exhibits a 7 to 10 dB reduction effect. In addition, such a silencer for the pressure reducing valve has a disadvantage in that it must be designed in a special structure in conjunction with the configuration of the valve, even if installed outside the pressure reducing valve must be exposed to the air for a long time, so the durability of the silencer that generates a lot of vibration must be secured. .

Therefore, there is a need for the application of a silencer that can be easily applied while having a more effective attenuation performance in the low-mid range between 500 and 1,000 Hz, and the development of a silencer that has excellent structural coupling force even when exposed to severe external environments. .

Therefore, the present invention was developed in view of the above circumstances, and has a more compact structure, exhibits effective sound absorption performance in the low-mid frequency components that influence sound performance, and exhibits structural bonding strength and tensile strength even when exposed to air. The purpose is to provide a strong sound absorbing resonance silencer.

In addition, the present invention has an object to provide a sound absorbing resonance silencer that can suppress the scattering of the sound absorbing material due to the flow of air in applying the sound absorbing silencer.

Sound absorbing resonance silencer of the present invention for achieving the above object is a plurality of hollow washer having a hole penetrated therein is arranged in the longitudinal direction in the passage through which the fluid passes and the fluid can pass through the silencer. In the gap between the washer and the washer, the noise characteristics of the bass and midrange are changed from the inside of the narrow passage to the treble region, so that the noise caused by the resonance is absorbed by the sound absorbing material on the rear side and prevents the sound absorbing material from passing through the gas. A perforated plate having a plurality of perforations formed therethrough is formed to surround the outside of the washer, and a sound absorbing material for absorbing noise is formed on the outside of the perforated plate, and a finish material surrounding the outside of the sound absorbing material is formed.

In addition, in the present invention, the washer has a circular hole, a rectangular hole and a rectangular shape, and the sound absorbing resonance silencer is characterized in that the cross-sectional shape of the sound absorbing resonator is circular or rectangular.

In addition, in the present invention, the washer is provided with a sound absorption resonance silencer, characterized in that arranged at a predetermined interval and the interval is 4 mm.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 3, in the first embodiment of the sound absorbing resonance silencer according to the present invention, resonance sound generated between a plurality of washers 121 and washers 121 arranged in the longitudinal direction of the silencer is absorbed into the sound absorbing material 124. Sound absorption is achieved by the structure to reduce the noise. The diameter of the inner tube 110 is merely the same size as the inner diameter of the washer and the inner tube is not formed through the interior of the silencer. That is, the center of the silencer has a passage for flow because a plurality of hollow park washer 121 is inserted. As can be seen from the overall configuration cross-sectional state of the sound-absorbing resonance silencer, the washers are arranged continuously, and the space is formed between the washers and the washers so that the air is resonant. The smaller the size of the space part is, the higher the frequency of the resonance sound is. The larger the size of the space part is, the lower the frequency of resonance sound is generated.

As the washer is provided in the longitudinal direction and the tube is not installed inside, it becomes structurally compact and thus prevents the transmission of structural vibration sound or solid transmission sound generated in the inner tube even though continuous external vibration occurs. In addition, the outer peripheral surface of the washer 121 is formed with a perforated plate 122 through which a plurality of perforations (not shown) and the sound absorbing material 124 is formed to reduce the resonance sound.

In addition, a sound absorbing material 124 is formed to absorb the reduced resonance sound on the outer circumferential surface of the perforated plate 122. In general, glass wool is widely applied to the sound absorbing silencer, but in the present invention, harmful effects on the human body may occur. Instead of fiberglass, Mitch applies Saslon, which is harmless to the human body. In addition, the perforated plate is a plate formed with a plurality of holes that are used as a surface material of the sound absorbing material, which is usually used a galvanized steel sheet.

 On the other hand, the outer peripheral surface of the sound absorbing material 124 is formed surrounded by a finish material 125 which is a steel plate.

The perforated plate and the sound absorbing material act as a so-called Helmholtz resonator, and sound energy is absorbed by heat energy through the sound absorbing material.

The damping amount of the sound-absorbing resonance silencer according to the present invention thus formed is 23 to 25 dB (A) attenuation per 1 m length, washer 121 is to use a steel washer 121 to ensure the rigidity of the washer In order to suppress the generation of singular sounds due to vibration of the plate, it is preferable to apply a thickness of about 5mm. In addition, depending on the frequency band to be attenuated, it is preferable to apply a 4 mm spacing between washers to reduce mid-band noise from the center frequency 500 Hz to 2000 Hz.

The cross-sectional shape of the sound absorbing resonance silencer according to the present invention is not limited to the shape of a circle or a square. If the shape is circular, the circular washer 121 is inserted into the outer circumference of the inner tube 110, and in the case of the square, the rectangular washer 121 is inserted. In addition, the general silencer uses a material that can not withstand the room temperature, whereas the sound absorbing resonance silencer of the present invention uses a steel plate capable of withstanding high temperatures of 300 ~ 400 ℃.

Resonance silencer of the present invention is formed in the order of finish, sound absorbing material, perforated plate, washer from the outermost and compact structure and at the same time through the flow path so as not to obstruct the flow path at all, regardless of performance when applied to an internal combustion engine, etc. It does not have a structure.

Looking at the operation of the sound-absorbing resonance silencer according to the invention of the configuration made as described above are as follows.

The silencer is installed at the outlet of the system or engine where noise is generated. The exhaust gas or the compressed air is incident at the inlet of the silencer, and the incident noise energy is formed in the longitudinal direction of the flow direction of the washer 121 and the washer ( Resonance phenomena in which the piston action and reflection are repeated in the spaces between 121) are generated, and the resonance sound generated by the resonance phenomenon is reduced by the perforated plate 122 and the sound absorbing material provided outside the washer.

That is, although the perforated plate and the sound absorbing material have a structure that functions as a conventional sound absorbing type silencer, in the present invention, the sound energy is primarily stored between the washers to increase the sound absorbing effect, and the stored resonance sound is stored in the perforated plate and the sound absorbing material 124. It is absorbed by) and disappears as heat energy.

Experiments were carried out for the sound absorbing resonance silencer according to the present invention. In FIG. 4, the experimental apparatus is illustrated. The noise source generator 150 generates a white noise including all frequency components at one end of the silencer. The white noise proceeds along the inner tube of the silencer and is discharged from the other end of the silencer. The other end of the silencer is provided with a microphone 200 that can measure the sound pressure.

Experiments were performed by comparing empty tubes with empty insides having the same radius as the sound-absorbing resonance silencer according to the present invention.

Compared with the experimental results, as shown in Table 1 and FIG. 4, the total noise level (AP) of 108.5 dB (A) generated by the noise generator is reduced while passing through a hollow tube of the same size as the silencer of the present invention is 85.1. While dB (A) reduces 24.3 dB, the total noise level that is reduced while passing through the silencer of the present invention is 60.6 dB (A), resulting in a 47.9 dB reduction, resulting in a reduction of 1 per unit length. The noise level is reduced to 24.5 dB (A) has a sound absorption effect is further reduced.

Table 1 shows the noise level of the silencer inlet side, the exit noise level to which the silencer of the present invention is applied, and the noise level of each outlet side of the empty tube having the same diameter as the silencer of the present invention for each octave band. In addition, Figure 4a and Figure 4b is a graph showing the results of the above Table 1 to measure the attenuation effect for each octave band.

As can be seen in Table 1, the silencer according to the present invention can be seen that the noise effect is greatly generated at the center frequency 500 Hz, 1000 Hz, 2000 Hz. A general muffler requires a reactance type silencer that is complex in structure and structure of a muffler in order to exhibit the noise effect in the frequency band as described above. However, the muffler according to the present invention has a compact structure, which provides excellent sound absorption characteristics of about 30 dB per unit length. It works.

In addition, the sound absorbing resonance silencer according to the present invention is a fluid flow pipe equal to the size of the pipe or duct to generate noise, so there is no pressure loss, but only a friction loss occurs. In addition, since the sound absorbing perforated plate and the sound absorbing material according to the present invention are located at the outer side of the washer, no scattering of the sound absorbing material occurs.

And the sound absorption resonance silencer of this invention does not specifically limit the application object. The above-described application apparatus described the pressure reducing valve of the high pressure steam feed pipe of the boiler, but in addition, the steam safety valve outlet, the lower part of the pressure reducing valve of the high pressure steam feed pipe of the boiler, the pipe that generates noise, the root blower fan inlet and the discharge hole that generate noise. , Generator pipe gas flue pipe, air compressor suction pipe, air compressor discharge pipe, diesel locomotive exhaust pipe and suction pipe, subway electric vehicle air pressure outlet, industrial air cylinder exhaust port, air extrusion blower suction and discharge pipe, pump discharge port and suction port and boiler It can be applied to flue pipes and the like.

As described above, the sound absorbing resonance silencer of the present invention has a compact structure in which the sound absorbing material and the washer are formed in the longitudinal direction, thereby providing an effect of reducing the sound of the frequency component of the low and mid range.

In addition, the sound-absorbing resonance silencer of the present invention has a compact structure, excellent tensile strength and bonding strength, and does not cause self-extinguishing and sparking with organic materials and has high heat resistance.

In addition, by installing a perforated plate formed with a perforation between the washer and the sound absorbing material, it is an environmentally friendly structure that has a strong bonding force even when exposed to air for a long time and hardly scatters due to weathering, and does not damage the product during transportation and handling and does not require a protective device. It provides an effect that can facilitate the work.

Claims (3)

A plurality of hollow washers having holes penetrated therein are inserted into the passage through which the fluid passes, and a perforated plate having a plurality of perforated holes formed therein to prevent scattering of the sound absorbing material while reducing resonance sound. The sound absorbing resonance silencer is formed while surrounding the outside, and the sound absorbing material for absorbing noise is formed on the outside of the perforated plate, the finishing material surrounding the outside of the sound absorbing material is formed. The method of claim 1, The washer has a rectangular hole and a rectangular shape, the sound absorbing resonance silencer, characterized in that the cross-sectional shape of the sound absorbing resonator is also rectangular. The method according to claim 1, The washer is disposed at a predetermined interval and the sound absorption resonance silencer, characterized in that the interval is 4 mm.

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