CN211449210U

CN211449210U - Resistive-resonant cavity composite muffler

Info

Publication number: CN211449210U
Application number: CN201922191859.6U
Authority: CN
Inventors: 张荷玲; 张大龙; 卢欢
Original assignee: Beijing Wanxunda Acoustics Equipment Co ltd
Current assignee: Beijing Wanxunda Acoustics Equipment Co ltd
Priority date: 2019-12-07
Filing date: 2019-12-07
Publication date: 2020-09-08
Anticipated expiration: 2029-12-07

Abstract

The utility model relates to a hindering nature-resonant cavity combined type silencer, including outer noise elimination body and be located the interior noise elimination body of outer noise elimination internal portion, leave the distance between outer noise elimination body and the interior noise elimination body, pass through vaulting pole fixed connection between outer noise elimination body and the interior noise elimination body. The outer noise elimination body comprises an outer shell and an outer perforated pipe, the two axial ends of the outer shell and the two axial ends of the outer perforated pipe are respectively connected, a distance is reserved between the outer shell and the outer perforated pipe to form an outer noise absorption cavity, and a sound absorption material is filled in the outer noise absorption cavity; the inner silencing body comprises an inner perforated pipe, and a plurality of resonant cavities are arranged in the inner perforated pipe; the two axial ends of the inner perforated pipe are respectively provided with a hollow flow guide cap, the flow guide cap is communicated with the inner perforated pipe, a cavity of the flow guide cap forms an inner sound absorption cavity, and the inner sound absorption cavity is filled with a sound absorption material. The utility model discloses set up sound absorbing material, inside at the outer wall of silencer and set up the resistance resonant cavity, can subduct wide band noise simultaneously, improved noise elimination effect.

Description

Resistive-resonant cavity composite muffler

Technical Field

The utility model belongs to the technical field of the technique of noise elimination equipment of making an uproar and specifically relates to a hindering nature-resonant cavity combined type silencer is related to.

Background

A muffler is a device that prevents sound from propagating while allowing airflow to pass through, and is an important measure for eliminating aerodynamic noise. When in use, the silencer is arranged on an airflow channel of aerodynamic equipment (such as a blower and an air compressor). The muffler can block the propagation of sound waves and allow air flow to pass through, and is an effective tool for controlling noise. Most of the existing silencers adopt impedance composite silencers. The impedance composite muffler refers to a muffler in which sound absorption and sound reflection are appropriately combined. The silencer has the characteristics of eliminating middle and high frequency noise by a resistive silencer and eliminating low and medium frequency noise by a resistive silencer, and has a broadband silencing effect.

The Chinese patent with the publication number of CN103727075B discloses a modular impedance compensation composite muffler, which comprises a three-section connecting assembly, namely a first resistive muffling pipe section, a second resistive muffling pipe section and a third resistive muffling pipe section, wherein a muffling plate assembly is arranged in the first pipe section, and the surface of the first pipe section, which is in contact with an air flow, is an aluminum perforated plate; the second pipe section and the third pipe section are unequal in length and comprise an outer panel, an inner mesh plate, a mesh ring frame support and a mesh ring frame cover plate, the mesh ring frame and the mesh ring frame support to form an expansion cavity, and a resonance cavity is formed between the outer panel and the mesh ring frame cover plate. The outside of the silencing piece component is an aluminum perforated plate, sound absorption materials are filled in the silencing piece component, and the first pipe section, the second pipe section and the third pipe section are riveted into a whole through rivets by rubber plates and clamps.

The prior art can achieve better muffling effect in the whole frequency band through impedance muffling and mutual compensation means. But the sectional arrangement mode on the outer wall of the silencer leads the gas flow to mainly adopt a resistance or reactive silencing mode in a certain stage in the process of passing through the silencer, achieves the aim of impedance combination by prolonging the length of the silencer, has no obvious effect of impedance combination in the same stage, and leads the length and the volume of the silencer to be increased by the sectional arrangement.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a hindering nature-resonant cavity combined type silencer sets up relative hindering nature noise elimination body and resistance noise elimination body with inside on the outer wall of silencer for the full route scope that the air current passes through in the silencer can carry out hindering nature noise elimination and resistance noise elimination simultaneously, realizes subducing the wide band of noise, has improved noise elimination efficiency, makes noise elimination effect better.

The above utility model discloses an above-mentioned utility model purpose can realize through following technical scheme:

a resistance-resonant cavity combined muffler comprises a tubular outer muffler body and an inner muffler body which is positioned inside the outer muffler body and coaxial with the outer muffler body, wherein a distance is reserved between the outer muffler body and the inner muffler body to form a channel allowing air flow to pass through, the outer muffler body and the inner muffler body are fixedly connected through a support rod, the outer muffler body comprises an outer shell far away from the inner muffler body and an outer perforated pipe close to the inner muffler body and provided with a plurality of through holes on the pipe wall, the outer shell and the outer perforated pipe are connected through fixing rings at two axial ends respectively, a distance is reserved between the outer shell and the outer perforated pipe to form an outer sound absorption cavity, and a sound absorption material is filled inside the outer sound absorption cavity; the inner noise elimination body comprises an inner perforated pipe which is provided with a plurality of through holes on the pipe wall and is hollow inside and sealed at two ends.

By adopting the technical scheme, the outer wall of the silencer is provided with the sound absorption material, and the interior of the silencer is provided with the reactive noise elimination resonant cavity, so that broadband noise can be eliminated simultaneously, and the noise elimination effect is improved.

The utility model discloses further set up to: the interior of the inner perforated pipe is divided into a plurality of cavities through a plurality of partition plates.

By adopting the technical scheme, the number of the resonant cavities is increased, so that the frequency of the noise reflected in the resonant cavities is increased, the residence time of the noise in the silencer is prolonged, and the silencing effect is improved.

The utility model discloses further set up to: a plurality of first spacers are arranged inside the inner perforated pipe at intervals along the axial direction of the inner perforated pipe, and the first spacers divide an inner cavity of the inner perforated pipe into a plurality of resonant cavities.

By adopting the technical scheme, the inner perforated pipe is divided into the plurality of resonant cavities which are arranged along the axial direction, the treatment times of noise in the silencer is increased by increasing the number of the resonant cavities, and the noise reduction quality is improved.

The utility model discloses further set up to: and the inner part of each inner perforated pipe is provided with a second spacer arranged along the axial direction of the inner perforated pipe, and each resonant cavity separated by the first spacer is separated into two cavities by the second spacer.

By adopting the technical scheme, the reflection distance of the noise in each resonant cavity is shortened, so that the reflection times of the noise are increased, and the processing efficiency of the noise is improved.

The utility model discloses further set up to: the perforation rate of the outer perforated pipe and the perforation rate of the inner perforated pipe axially positioned at different resonant cavities are different.

Through adopting above-mentioned technical scheme, the setting of multiple perforation rate makes the noise that the silencer can handle in the wider frequency channel scope.

The utility model discloses further set up to: the axial two ends of the inner perforated pipe are respectively provided with a flow guide cap with the diameter equal to that of the inner perforated pipe, and the end of the two flow guide caps departing from each other is an arc-shaped surface.

By adopting the technical scheme, the flow guide cap divides the air flow passing through the silencer, so that the pressure of the facing air flow on the inner silencer is reduced, namely the resistance of the flow guide cap on the air flow facing air flow is reduced.

The utility model discloses further set up to: the flow guide cap comprises a cap shell with a hollow inner part, a plurality of through holes are respectively formed in the end faces of the two axial ends of the inner perforated pipe, and the cavity of the cap shell is communicated with the cavity of the inner perforated pipe through the through holes in the end faces of the two axial ends of the inner perforated pipe.

By adopting the technical scheme, the space of the flow guide cap is fully utilized to reduce the noise.

The utility model discloses further set up to: the cap shell is characterized in that the cavity of the cap shell is an inner sound absorption cavity, and sound absorption materials are filled in the inner sound absorption cavity.

By adopting the technical scheme, the inner sound absorption cavity performs resistive sound absorption treatment on the middle and high frequency bands of the entering noise.

The utility model discloses further set up to: the sound absorption materials filled in the outer sound absorption cavity and the inner sound absorption cavity are all made of centrifugal glass wool felt.

By adopting the technical scheme, the glass wool is made of porous materials, so that the sound absorption performance is good, and the cost is low.

To sum up, the utility model discloses a beneficial technological effect does:

1. the resistive noise elimination body and the reactive noise elimination body are arranged on the outer wall and inside the silencer, so that resistive noise elimination and reactive noise elimination can be simultaneously carried out in the whole path range of air flow passing through the silencer, the broadband reduction of noise is realized, the noise elimination efficiency is improved, and the noise elimination effect is better. (ii) a

2. The sound absorption cavities are arranged at the two ends of the internal resonant cavity, so that the noise treated by the resonant cavity can quickly enter the sound absorption cavity to be treated in a middle-high frequency range, and the noise reduction speed is accelerated;

3. the perforation rates of the resonant cavities are designed to be different values, so that the resonant cavities can process noise in a wider frequency range, and the processing effect of the noise in the middle and low frequency ranges is improved.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention;

fig. 2 is a cross-sectional view of the present invention.

In the figure, 1, an outer muffler body; 11. an outer housing; 12. an outer perforated tube; 13. a fixing ring; 14. an outer acoustic cavity; 2. an inner muffler body; 21. an inner perforated tube; 211. a first resonant cavity; 212. a second resonant cavity; 213. a third resonant cavity; 22. a flow guide cap; 221. a cap shell; 222. an inner acoustic absorption cavity; 23. a first spacer; 24. a second spacer; 3. a stay bar; 4. a flange connecting plate; 5. a sound absorbing material; 6. an air inlet; 7. and an air outlet.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1 and 2, a resistive-resonant cavity composite muffler disclosed in the present invention includes a tubular outer muffler body 1 and a tubular inner muffler body 2 disposed inside the outer muffler body 1 and coaxial with the outer muffler body 1. The outer muffler body 1 and the inner muffler body 2 are spaced apart from each other to form a passage for allowing the passage of air, and the axial ends of the passage are an air inlet 6 and an air outlet 7, respectively. The inner noise elimination body 2 is fixed inside the outer noise elimination body 1 through a plurality of support rods 3, and two ends of each support rod 3 are fixedly connected with the inner noise elimination body 2 and the outer noise elimination body 1 respectively.

The outer muffler body 1 includes an outer shell 11 having an outer circular tubular shape and an outer perforated pipe 12 located inside the outer shell 11 and disposed coaxially with the outer shell 11. The length of the outer perforated tube 12 is longer than the length of the outer shell 11. Both ends of the outer perforated pipe 12 in the axial direction extend from both end faces of the outer shell 11 in the axial direction, respectively. The outer walls of the two axial ends of the outer perforated pipe 12 are provided with fixing rings 13 extending out of the outer shell 11, and the fixing rings 13 are coaxial with the outer perforated pipe 12. The fixing rings 13 are fixedly connected to the outer housing 11 and the inner perforated tube 12, respectively.

The outer diameter of the outer perforated tube 12 is smaller than the inner diameter of the outer housing 11 so that an outer sound-absorbing chamber 14 is formed between the outer perforated tube 12 and the outer housing 11. The wall of the outer perforated pipe 12 is provided with a plurality of through holes penetrating through the wall of the outer perforated pipe 12. The sound absorption material 5 is filled in the outer sound absorption cavity 14, and the sound absorption material 5 is made of centrifugal glass wool felt. The sound generated by the gas flow between the inner muffler body 2 and the outer muffler body 1 can be absorbed and attenuated by the sound-absorbing material 5 in the outer sound-absorbing chamber 14.

The inner muffler body 2 includes an inner perforated pipe 21 coaxially disposed with the outer muffler body 1, and the inner perforated pipe 21 is hollow and closed at both ends. The two ends of the inner perforated pipe 21 in the axial direction are respectively provided with a hemispherical deflector cap 22. The spherical diameter of the deflector cap 22 is equal to the outer diameter of the inner perforated pipe 21. The arc-shaped surface of the deflector cap 22 is disposed away from the inner perforated tube 21. The diversion cap 22 and the inner perforated pipe 21 are fixedly arranged. The deflector cap 22 divides the air flow passing through the muffler, and reduces the pressure of the facing air flow on the inner muffler body 2.

Two circular first spacers 23 partitioning the inner hollow space of the inner perforated tube 21 are provided inside the inner perforated tube 21 at intervals in the axial direction of the inner perforated tube 21, and the diameter of the first spacers 23 is equal to the inner diameter of the inner perforated tube 21. The first spacer 23 is fixedly connected to the inner perforated tube 21. The two first spacers 23 equally divide the inner cavity of the inner perforated tube 21 into three sections in the axial direction, and the first resonance chamber 211, the second resonance chamber 212, and the third resonance chamber 213 are arranged in this order from the gas inlet 6 to the gas outlet 7. The pipe wall of the inner perforated pipe 21 is provided with a plurality of through holes which penetrate through the pipe wall of the inner perforated pipe 21. The resonant cavity can reduce and treat the noise of the middle and low frequency bands passing through the silencer. Meanwhile, the resonant cavity receives the noise of the outer noise elimination body 1, which is already reduced by the middle and high frequency bands, and the middle and low frequency bands are processed.

The deflector cap 22 includes a hemispherical cap shell 221 having a hollow inside, and a space inside the cap shell 221 forms an internal sound absorption chamber 222. The inner sound-absorbing chamber 222 is filled with a sound-absorbing material 5. The sound absorption material 5 filled in the inner sound absorption cavity 222 adopts centrifugal glass wool felt. The end faces of the two axial ends of the inner perforated pipe 21 are provided with a plurality of through holes which penetrate through the end faces along the axial direction of the inner perforated pipe 21. The inner sound absorption chamber 222 communicates with the first resonance chamber 211 and the third resonance chamber 213 through holes formed in both end surfaces of the inner perforated tube 21 in the axial direction. The inner sound absorption cavity 222 utilizes the sound absorption material 5 inside to process the noise from and processed by the first resonant cavity 211 and the third resonant cavity 213 in the middle and high frequency range, thereby improving the noise reduction effect.

The perforation rate of outer perforated tube 12, the perforation rate of inner perforated tube 21 at first resonant cavity 211, the perforation rate of inner perforated tube 21 at second resonant cavity 212, and the perforation rate of inner perforated tube 21 at third resonant cavity 213 are all different. The resonant cavity and the sound absorption cavity with various perforation rates are arranged at different stages of the airflow channel, so that the noise frequency range which can be processed by the silencer is larger, and the silencing effect is better. Meanwhile, the multi-frequency resistive-resistant noise elimination is also beneficial to improving the noise elimination effect.

Inside each of first resonant cavity 211, second resonant cavity 212, and third resonant cavity 213, there is provided a second diaphragm 24 disposed axially along inner perforated tube 21, second diaphragm 24 separating the inside of first resonant cavity 211, second resonant cavity 212, and third resonant cavity 213 into two cavities disposed side by side along the radial direction of inner perforated tube 21. The first resonant cavity 211, the second resonant cavity 212 and the third resonant cavity 213 are divided, so that the reflection distance of noise in the resonant cavities is shortened, the reflection frequency is increased, and the noise elimination effect is improved.

And two ends of the outer perforated pipe 12 in the axial direction are respectively provided with a flange connecting plate 4. The flange connection disc 4 is in a circular ring shape, the flange connection disc 4 and the outer perforated pipe 12 are coaxially arranged, and an inner hole of the flange connection disc 4 is opposite to an inner hole of the outer perforated pipe 12. The flange connecting disc 4 and the outer perforated pipe 12 are welded and fixed. The flange connecting plate 4 is used for connecting the silencers or connecting the silencers with other pipeline equipment.

The implementation principle of the embodiment is as follows: the inner muffler body 2 and the outer muffler body 1 are connected by a stay bar 3, and the muffler is connected to the ventilation duct by a flange connection plate 4. The outer silencer 1 utilizes the sound absorption material 5 in the outer sound absorption cavity 14 to reduce the middle and high frequency range noise passing through the silencer, and reflects the untreated middle and low frequency range noise to the inner silencer 2 for treatment; the inner muffler body 2 reduces the middle and low frequency band noise passing through the muffler by using the first resonant cavity 211, the second resonant cavity 212 and the third resonant cavity 213 with different perforation rates, and reflects the untreated middle and high frequency band noise to the outer sound absorption cavity 14 for treatment. The inner acoustic absorption chamber 222 can attenuate noise from the first resonant chamber 211 and the third resonant chamber 213. Through the arrangement, the characteristics of resistive noise elimination and resistive noise elimination are utilized, the noise is reduced for multiple times when passing through the silencer, and the noise elimination effect of the noise is obviously improved.

The embodiment of this specific implementation mode is the preferred embodiment of the present invention, not limit according to this the utility model discloses a protection scope, so: all equivalent changes made according to the structure, shape and principle of the utility model are covered within the protection scope of the utility model.

Claims

1. A resistive-resonant cavity composite muffler comprises a tubular outer muffler body (1) and an inner muffler body (2) which is positioned inside the outer muffler body (1) and coaxial with the outer muffler body (1), wherein a distance is reserved between the outer muffler body (1) and the inner muffler body (2) to form a channel allowing air flow to pass through, and the outer muffler body (1) and the inner muffler body (2) are fixedly connected through a support rod (3), and the resistive-resonant cavity composite muffler is characterized in that: the outer noise elimination body (1) comprises an outer shell (11) far away from the inner noise elimination body (2) and an outer perforated pipe (12) close to the inner noise elimination body (2) and provided with a plurality of through holes on the pipe wall, the outer shell (11) and the outer perforated pipe (12) are connected at two axial ends through fixing rings (13), a distance is reserved between the outer shell (11) and the outer perforated pipe (12) to form an outer sound absorption cavity (14), and a sound absorption material (5) is filled in the outer sound absorption cavity (14); the inner noise elimination body (2) comprises an inner perforated pipe (21) which is provided with a plurality of through holes on the pipe wall and is hollow inside and closed at two ends.

2. The resistive-resonant cavity composite muffler of claim 1, wherein: the interior of the inner perforated pipe (21) is divided into a plurality of cavities through a plurality of partition plates.

3. The resistive-resonant cavity composite muffler of claim 2, wherein: a plurality of first spacers (23) are arranged inside the inner perforated pipe (21) at intervals along the axial direction of the inner perforated pipe (21), and the first spacers (23) divide the inner cavity of the inner perforated pipe (21) into a plurality of resonant cavities.

4. The resistive-resonant cavity composite muffler of claim 3, wherein: and second spacers (24) axially arranged along the inner perforated pipe (21) are arranged in the inner perforated pipe (21), and each resonant cavity separated by the first spacers (23) is separated into two cavities by the second spacers (24).

5. The resistive-resonant cavity composite muffler of claim 3, wherein: the perforation rate of the outer perforated pipe (12) and the perforation rate of the inner perforated pipe (21) at different resonant cavities in the axial direction are different.

6. The resistive-resonant cavity composite muffler of claim 1, wherein: the axial two ends of the inner perforated pipe (21) are respectively provided with a diversion cap (22) with the same diameter as the inner perforated pipe (21), and one end of the two diversion caps (22) which deviates from each other is an arc-shaped surface.

7. The resistive-resonant cavity composite muffler of claim 6, wherein: the flow guide cap (22) comprises a hollow cap shell (221), a plurality of through holes are formed in the end faces of the two axial ends of the inner perforated pipe (21), and the cavity of the cap shell (221) is communicated with the cavity of the inner perforated pipe (21) through the through holes in the end faces of the two axial ends of the inner perforated pipe (21).

8. The resistive-resonant cavity composite muffler of claim 7, wherein: the cap shell (221) is characterized in that the cavity is an inner sound absorption cavity (222), and sound absorption materials (5) are filled in the inner sound absorption cavity (222).

9. The resistive-resonant cavity composite muffler of claim 8, wherein: the sound absorption materials (5) filled in the outer sound absorption cavity (14) and the inner sound absorption cavity (222) are all made of centrifugal glass wool felt.