CN109405262A - Pipeline Active noise control system, active-passive composite pipeline silencer - Google Patents
Pipeline Active noise control system, active-passive composite pipeline silencer Download PDFInfo
- Publication number
- CN109405262A CN109405262A CN201811538970.1A CN201811538970A CN109405262A CN 109405262 A CN109405262 A CN 109405262A CN 201811538970 A CN201811538970 A CN 201811538970A CN 109405262 A CN109405262 A CN 109405262A
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- Prior art keywords
- noise
- pipeline
- controller
- signal
- microphone
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Links
- 230000003584 silencer Effects 0.000 title claims abstract description 22
- 239000002131 composite material Substances 0.000 title claims abstract description 13
- 230000008030 elimination Effects 0.000 claims abstract description 17
- 238000003379 elimination reaction Methods 0.000 claims abstract description 17
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 12
- 230000005540 biological transmission Effects 0.000 claims abstract description 4
- 239000013078 crystal Substances 0.000 claims description 10
- 238000009434 installation Methods 0.000 claims description 5
- 238000005192 partition Methods 0.000 claims description 4
- 230000002745 absorbent Effects 0.000 claims description 3
- 239000002250 absorbent Substances 0.000 claims description 3
- 238000005253 cladding Methods 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 4
- 238000005516 engineering process Methods 0.000 description 12
- 230000008901 benefit Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 229920000742 Cotton Polymers 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 230000003044 adaptive effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 241000208340 Araliaceae Species 0.000 description 1
- 235000005035 Panax pseudoginseng ssp. pseudoginseng Nutrition 0.000 description 1
- 235000003140 Panax quinquefolius Nutrition 0.000 description 1
- 238000004378 air conditioning Methods 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 235000008434 ginseng Nutrition 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
- F24F2013/242—Sound-absorbing material
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
- F24F13/24—Means for preventing or suppressing noise
- F24F2013/247—Active noise-suppression
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
- Exhaust Silencers (AREA)
Abstract
The present disclosure proposes a kind of pipeline Active noise control systems, active-passive composite pipeline silencer, wherein the pipeline Active noise control system includes: with reference to microphone, for obtaining the noise signal of upstream；Controller is connect with described with reference to microphone, for receiving the signal sent with reference to microphone and generating control signal；Sub-loudspeaker, for receiving the control signal of the controller transmission and generating reverse phase secondary noise, so that the noise to downstream pipe controls.Disclosure pipeline Active noise control system, active-passive composite pipeline silencer, low frequency anechoic frequency bandwidth improve noise elimination effect, meet the broad band low frequency requirement of ventilating system pipeline noise.
Description
Technical field
The disclosure belongs to the noise elimination technique field of the fields such as building, rail traffic, ship ventilating system pipeline, more particularly to
A kind of pipeline Active noise control system, active-passive composite pipeline broadband muffler and piping installation.
Background technique
With the continuous promotion that resident, passenger and crewman pay attention to work, living condition comfort, indoor noise circumstance
It is paid close attention to as each side one of an important factor for measuring comfort, is increasingly subject to.
Air-conditioning ventilation system meets inhabitation personnel thermal comfort and health as good indoor air environment is created
Important equipment, operating when inevitably bring noise, wherein ventilating system pipeline be most important noise transmission approach it
One.Ventilating system pipeline noise is mainly derived from the pneumatic noise in fan noise and pipeline, according to a large amount of field test,
Apparent broad band low frequency characteristic is presented.For ventilating system pipeline noise is effectively reduced, installing silencer additional in pipeline is to have the most
The method of effect.
Currently used passive silencer or low frequency noise elimination frequency band are narrow, or effectively frequency of noise elimination is excessively high, generally deposits
The disadvantages of low frequency noise elimination effect is undesirable, drag losses are big, volume and weight is big, it is difficult to meet ventilating system pipeline noise
Broad band low frequency control require.
Summary of the invention
(1) technical problems to be solved
Present disclose provides a kind of pipeline Active noise control system, active-passive composite pipeline broadband muffler and pipeline dresses
It sets, at least partly to solve technical problem set forth above.
(2) technical solution
According to one aspect of the disclosure, a kind of pipeline Active noise control system is provided, comprising:
With reference to microphone, for obtaining the noise signal of upstream；
Controller is connect with described with reference to microphone, for receiving the signal sent with reference to microphone and generating control
Signal processed；
Sub-loudspeaker, for receiving the control signal of the controller transmission and generating reverse phase secondary noise, thus right
The noise of downstream pipe is controlled.
In some embodiments, the controller is using the noise signal of the upstream as reference signal, to the ginseng
It examines signal and is filtered the generation control signal.
In some embodiments, the system further include: error microphone is connect, for obtaining with the controller
The noise signal of downstream pipe is simultaneously sent to the controller.
In some embodiments, the controller receive the downstream pipe that the error microphone is sent noise signal and
The noise signal of the upstream sent with reference to microphone, and according to the noise signal and upstream of the downstream pipe
Noise signal correct the control signal.
In some embodiments, the system further includes power amplifier, is connect with the controller and the sub-loudspeaker,
The power amplifier receives the control signal that the controller is sent, and sends it to the sub-loudspeaker, drives the secondary
Loudspeaker generates the antiphase secondary noise.
A kind of active-passive composite pipeline silencer another aspect of the present disclosure provides, including the pipeline
Active noise control system and muffler body；Wherein, the muffler body includes that pipe passage and the cladding pipeline are logical
The cavity structure in road.
In some embodiments, the cavity structure include input end chamber, outlet end chamber and be located at input end chamber,
Intermediate cavity between the chamber of outlet end；Reference microphone and the controller are installed in the input end chamber,
It is equipped with phonon crystal periodicity noise elimination structure and absorbent tampons in the intermediate cavity, is equipped in the outlet end chamber described
Sub-loudspeaker and the error microphone.
In some embodiments, the phonon crystal periodicity noise elimination structure includes:
First panel is microperforated panel, coats the pipe passage；
Second panel is oppositely arranged with the first panel；And
Multiple partitions are uniformly arranged between the first panel and second panel.
In some embodiments, the first panel is variable diameter microperforated panel.
According to the another aspect of the disclosure, a kind of piping installation is provided comprising pipeline and the silencer,
Described in pipeline be arranged in the pipe passage of the silencer.
(3) beneficial effect
(1) disclosure pipeline Active noise control system includes: and utilizes with reference to microphone, controller and sub-loudspeaker
Sub-loudspeaker generates reverse phase secondary noise, can improve low frequency noise elimination effect, the low frequency for meeting ventilating system pipeline noise is wide
Band requires.
(2) disclosure pipeline Active noise control system and muffler, structure is simple, is conducive to reduce volume and weight,
It is convenient to use.
(3) it is designed using the structure of active-passive composite, wherein passive part introduces phonon crystal technology and resistance noise reduction skill
Art is good at by phonon crystal technology in the noise elimination advantage of intermediate frequency and the high frequency noise elimination advantage of resistive technology with active control technology
The characteristics of controlling low-frequency noise combines, and forms the ventilating system pipeline acoustical absorptivity of covering Whole frequency band.
(4) wind face is crossed in silencer internal wall, the variable diameter microperforated panel construction small using resistance, pneumatic noise is small, reference
Microphone may be arranged at the interior acquisition signal of cavity after microperforated panel, and air-flow must be goed deep by avoiding microphone in traditional technology, easily
Incoming flow reference noise can not be accurately measured by turbulent flow interference, the shortcomings that can only using at low wind speeds.
(5) the multi channel adaptive control device for using the feedback mixed structure before digital based on FPGA, can preferably fit
Answer the variation of operating condition.
Detailed description of the invention
Fig. 1 is according to disclosure pipeline Active noise control system structural schematic diagram.
Fig. 2 is according to disclosure active-passive composite pipeline broadband muffler structural schematic diagram.
<symbol description>
1- refer to microphone, 2- controller, 3- power amplifier, 4- sub-loudspeaker, 5- error microphone, 6- input end chamber,
7- intermediate cavity, the outlet end 8- chamber, 9- pipe passage, 10- sound absorption cotton, 11- microperforated panel, the common orifice plate of 12-, 13- partition,
S1- fan noise, S2- reference signal, S3- control signal.
Specific embodiment
For the purposes, technical schemes and advantages of the disclosure are more clearly understood, below in conjunction with specific embodiment, and reference
The disclosure is further described in attached drawing.
The disclosure is mentioned primarily directed to the ventilating system pipeline noise problem of the technical fields such as building, rail traffic, ship
Inhibit pipeline Active noise control system, the active-passive composite pipeline broadband muffler of pipeline noise in a kind of wide frequency range out.
Compared with existing pipeline noise impedance, the disclosure uses the structure of active-passive composite, and wherein operand separates
Enter phonon crystal technology and resistance noise reduction technology, phonon crystal technology is disappeared in the noise elimination advantage of intermediate frequency and the high frequency of resistive technology
Sound advantage combines the characteristics of active control technology is good at control low-frequency noise, and the ventage for forming covering Whole frequency band is under the overall leadership
Road acoustical absorptivity.
In one embodiment, as shown in Figure 1, disclosure pipeline Active noise control system includes: with reference to microphone 1, control
Device 2, power amplifier 3, sub-loudspeaker 4 and error microphone 5 processed.The initial noisc letter that upstream is picked up with reference to microphone
Number, and as reference signal S2 input controller；The controller is filtered generation control letter to the reference signal
Number S3, and drive the sub-loudspeaker to issue antiphase secondary noise signal by the power amplifier, to realize to downstream tube
Effective control of the noise on road.
The error microphone is used to be monitored pipe line downstream noise, obtains the noise signal of downstream pipe, thus
Filter in controller described in offline design or online updating.Specifically, the controller receives the error microphone hair
The noise signal (reference signal) of the noise signal of the downstream pipe sent and the upstream sent with reference to microphone, and root
The control signal is corrected according to the noise signal of the downstream pipe and the noise signal of upstream.
Controller described in the present embodiment uses the multi channel adaptive control of the feedback mixed structure before digital based on FPGA
Device can well adapt to the variation of operating condition, using the regular lowest mean square Active control mode of post filtering, can effectively improve system
Convergence rate, stability and noise reduction.
As shown in Fig. 2, disclosure active-passive composite broadband muffler includes the pipeline Active noise control system and disappears
Sound device ontology.Wherein, the muffler body includes the cavity structure of pipe passage 9 and the cladding pipe passage.The sky
Cavity configuration includes input end chamber 6, positioned at the input end of muffler pipe paths；It is logical to be located at silencer pipeline for outlet end chamber 8
The outlet end in road and the intermediate cavity 7 between input end chamber, outlet end chamber.In muffler body input end chamber
It is interior, reference microphone 1 and the controller 2 are installed, phonon crystal periodicity noise elimination structure is equipped in intermediate cavity
With absorbent tampons 10, set in the chamber of outlet end there are two sub-loudspeaker 4 and error microphone 5.
The quantity of each component included by silencer is not limited to the quantity limited in embodiment, example in certain disclosure
Such as, the quantity of sub-loudspeaker is not limited to two gone out given in embodiment.
The phonon crystal periodicity noise elimination structure includes: microperforated panel 11, coats the pipe passage；Common orifice plate
(perforated plate) 12 is oppositely arranged with the microperforated panel；Multiple partitions 13, are uniformly arranged on the microperforated panel and common orifice plate
Between；And sound absorption cotton 10, coat the common orifice plate.
Disclosure noise elimination structure is axially in periodic arrangement along pipeline, can form multiple acoustic band gaps, is made an uproar with abundant inhibition
Sound.
Preferably, the microperforated panel 11 is variable diameter microperforated panel.Wind face is crossed in silencer internal wall, small using resistance,
The small variable diameter microperforated panel of pneumatic noise, makes that noise elimination bandwidth is wider, drag losses are smaller, may be arranged at micropunch with reference to microphone
Signal is acquired in cavity after plate, air-flow must be goed deep by avoiding microphone in traditional technology, can not be accurate vulnerable to turbulent flow interference
Measuring incoming flow reference noise can be according to use environment spread the technical issues of can only using at low wind speeds.
In addition, the disclosure additionally provides a kind of piping installation comprising pipeline and the silencer, wherein the pipeline
It is arranged in the pipe passage of the silencer.Specifically, the piping installation can be the logical of building, rail traffic, ship etc.
Air pipe line device.
Noise impedance technology is introduced into the design of ventilating system pipeline silencer by the disclosure, is sent out by secondary sound source
Antiphase sound wave out reaches the former noisy purpose of counteracting.
Particular embodiments described above has carried out further in detail the purpose of the disclosure, technical scheme and beneficial effects
Describe in detail bright, it should be understood that the foregoing is merely the specific embodiment of the disclosure, be not limited to the disclosure, it is all
Within the spirit and principle of the disclosure, any modification, equivalent substitution, improvement and etc. done should be included in the protection of the disclosure
Within the scope of.
Claims (10)
1. a kind of pipeline Active noise control system, comprising:
With reference to microphone, for obtaining the noise signal of upstream；
Controller is connect with described with reference to microphone, for receiving the signal sent with reference to microphone and generating control letter
Number；
Sub-loudspeaker, for receiving the control signal of the controller transmission and generating reverse phase secondary noise, thus to downstream
The noise of pipeline is controlled.
2. system according to claim 1, wherein the controller is using the noise signal of the upstream as reference
Signal is filtered the reference signal and generates the control signal.
3. system according to claim 1, further includes: error microphone is connect, for obtaining downstream with the controller
The noise signal of pipeline is simultaneously sent to the controller.
4. system according to claim 3, wherein the controller receives the downstream pipe that the error microphone is sent
Noise signal and it is described with reference to microphone send upstream noise signal, and according to the noise of the downstream pipe believe
Number and the noise signal of upstream correct the control signal.
5. system according to claim 1 further includes power amplifier, it is connect with the controller and the sub-loudspeaker, institute
It states power amplifier and receives the control signal that the controller is sent, and send it to the sub-loudspeaker, the secondary is driven to raise
Sound device generates the antiphase secondary noise.
6. a kind of active-passive composite pipeline silencer is actively controlled including the pipeline noise as described in any one of claims 1 to 5
System processed and muffler body；Wherein, the muffler body includes the cavity knot of pipe passage and the cladding pipe passage
Structure.
7. silencer according to claim 6, wherein the cavity structure include input end chamber, outlet end chamber and
Intermediate cavity between input end chamber, outlet end chamber；It is equipped in the input end chamber described with reference to transaudient
Device and the controller are equipped with phonon crystal periodicity noise elimination structure and absorbent tampons, in the outlet in the intermediate cavity
It holds and is equipped with the sub-loudspeaker and the error microphone in chamber.
8. silencer according to claim 7, wherein the phonon crystal periodicity noise elimination structure includes:
First panel is microperforated panel, coats the pipe passage；
Second panel is oppositely arranged with the first panel；And
Multiple partitions are uniformly arranged between the first panel and second panel.
9. silencer according to claim 8, wherein the first panel is variable diameter microperforated panel.
10. a kind of piping installation comprising pipeline and the silencer as described in any one of claim 6 to 9, wherein the pipe
Road is arranged in the pipe passage of the silencer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811538970.1A CN109405262A (en) | 2018-12-14 | 2018-12-14 | Pipeline Active noise control system, active-passive composite pipeline silencer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811538970.1A CN109405262A (en) | 2018-12-14 | 2018-12-14 | Pipeline Active noise control system, active-passive composite pipeline silencer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109405262A true CN109405262A (en) | 2019-03-01 |
Family
ID=65459468
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811538970.1A Pending CN109405262A (en) | 2018-12-14 | 2018-12-14 | Pipeline Active noise control system, active-passive composite pipeline silencer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109405262A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110843831A (en) * | 2019-11-18 | 2020-02-28 | 中科振声（苏州）电子科技有限公司 | Distribution box, air conditioner pipe system and air conditioner of making an uproar fall |
| CN114396523A (en) * | 2022-02-24 | 2022-04-26 | 中国人民解放军海军工程大学 | Silencer for liquid filling pipeline |
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| CN104165255A (en) * | 2013-05-17 | 2014-11-26 | 中国科学院声学研究所 | Active-passive composite silencer for ventilation pipeline |
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| CN114396523A (en) * | 2022-02-24 | 2022-04-26 | 中国人民解放军海军工程大学 | Silencer for liquid filling pipeline |
| CN114396523B (en) * | 2022-02-24 | 2024-05-03 | 中国人民解放军海军工程大学 | Active and passive composite muffler for liquid filling pipeline |
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Effective date of abandoning: 20241008 |