CN106015818A - Noise elimination energy-saving pipeline - Google Patents
Noise elimination energy-saving pipeline Download PDFInfo
- Publication number
- CN106015818A CN106015818A CN201610530255.8A CN201610530255A CN106015818A CN 106015818 A CN106015818 A CN 106015818A CN 201610530255 A CN201610530255 A CN 201610530255A CN 106015818 A CN106015818 A CN 106015818A
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- China
- Prior art keywords
- pipeline
- energy
- saving
- noise
- sound
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/02—Energy absorbers; Noise absorbers
- F16L55/033—Noise absorbers
Abstract
The invention discloses a noise elimination energy-saving pipeline. The noise elimination energy-saving pipeline comprises a pipeline inlet, a pipeline body and a pipeline outlet; the pipeline body is arranged between the pipeline inlet and the pipeline outlet and comprises one or more pipeline sets, and each pipeline set is composed of two independent branch pipelines; after sound waves enter the pipeline sets, the sound waves are divided into different paths along two branch pipelines of each pipeline set to be propagated; and finally, after the sound waves are propagated out of each pipeline set to be joined, the phase difference of the sound waves propagated out of two corresponding branch pipelines is odd times. On the basis of the sound wave interference offsetting principle, sound elimination and flow stabilizing are ingeniously combined together, the good sound elimination is achieved, and the energy-saving flow stabilizing effect is achieved.
Description
Technical field
The technology of the present invention relates to a kind of energy-saving silencing pipeline, belongs to smeltery, oil plant, coal-burning power plant's heat-exchange system, sky
Adjust and the energy saving ventilation system of other field.
Background technology
Produce during the fan operation of smeltery, oil plant, coal-burning power plant's heat-exchange system, air conditioning system and other ventilating systems
Noise in addition to a part is transmitted to surrounding space environment by blower fan and tube wall, also have major part noise along tubing pass
Broadcast, be radiated free surrounding space by pipeline air inlet.Meanwhile, in tubing quadratic noise produced by air current flow also by
Both the above approach is radiated surrounding space.This two parts noise the work of periphery personnel and life all can be produced bigger not
Profit impact.
Efficiently, the design object pursued of energy-conservation always ventiduct system, and pipeline flow field characteristic is this mesh
Target key influence factor.In uneven pipeline, flow velocity and pressure distribution will reduce drafting efficiency, increase equipment running resistance,
And these cause often caused by pipe design parameter is unreasonable.In ventilation shaft designs, air-flow flow field in pipeline
Extremely complex, especially in pipe bent position, the speed of gas and pressure all occur significantly to change, and produce turbulent flow, are to cause pipeline pressure
The main cause of power loss, the most easily causes higher reproduced air-flow noise and vibration.
At present for the noise abatement of ventiduct system, the general sound insulation using blower fan and pipeline thereof processes；Pipeline enters
Air port arranges the measures such as air-inlet sound eliminator.The sound insulation of blower fan and tubing thereof processes, and can reduce noise in blower fan and pipeline
Direct out the noisiness of radiation；Tubing air inlet installs acoustic filter additional, it is possible to decrease blower fan and pneumatic noise are outside along pipeline
The noisiness of radiation.But both the above noise abatement measure is imitated for the improvement of low-frequency noise produced by blower fan and air current flow
The poorest, especially under Wind Volume, conditions of high flow rate, the acoustic attenuation performance of air-inlet sound eliminator declines even to be lost.Meanwhile, pipeline enters
The pressure loss of wind acoustic filter is often several times even tens times of the own pressure loss of ventilation shaft, after installing air-inlet sound eliminator additional
Largely increase the aeration resistance of pipeline, under identical air quantity requires, increase blower fan input power, make again energy consumption
Increase.
Under harsh energy-saving and emission-reduction pressure and environmental noise abatement require, there is energy-conservation and from acoustic attenuation performance bend pipe,
The developing direction of this technology will be become.
Authorized announcement date is on 09 30th, 2014, and Authorization Notice No. is in the Chinese patent of CN204164042U, open
A kind of discharge bend muffler for 35kV transformer chamber, installs and the going out of the wall type axial flow blower on 35KV transformer chamber outer wall
At air port, including shell and the ventilation cavity being located in shell, ventilation cavity is respectively equipped with air intake vent on described shell and goes out
Air port, the centrage of ventilation cavity air intake vent overlaps with the centrage of locular wall formula axial flow blower, also includes being arranged on shell
And be positioned at the stainless steel cloth at air outlet and be arranged at ventilation cavity center the anechoic sheet extending along direction extension, eliminate the noise
The wind inlet end of sheet is provided with between conical flow guiding part, and the top of this conical flow guiding part and the residing plane of air intake vent and is provided with gap,
The other end of anechoic sheet and the planes align residing for air outlet.The overall sound deadening capacity of the technology of the present invention discharge bend muffler is higher,
Relatively prior art can improve more than 3dB (A), and has more preferable soundproof effect at the crest frequency of 35kV transformer noise.Should
Bend muffler use resistive sound-absorbing material formed silencing channel mode reach eliminate the noise purpose, but its noise elimination frequency band mainly for
Medium-high frequency, according to the version of its passage, the sound deadening capacity of passage is relatively low and environmental suitability is poor.Simultaneously because inner-walls of duct
It is filled with sound-absorbing material, relatively increases the resistance of bend pipe, and volume is bigger.
Authorized announcement date is on 09 26th, 2011, and Authorization Notice No. is in the Chinese patent of CN202248777U, open
The energy-saving elbow structure of a kind of thermal power plant flue gas system, including wallboard, reinforcing rib, it is characterised in that: wallboard composition four
The continuous print road body in face, in road body central axial along air-flow and connect two side wall panels be provided with aerofoil profile guiding device.This is energy-conservation curved
Head, for reducing pipeline crushing, improves its interior flow field and has bigger positive role, but simply improve in terms of noise-and-vibration-reduction
Turbulent condition in pipeline, reduces quadratic noise produced by turbulent air flow and vibration, and elbow itself is not eliminated the noise energy
Power.
Summary of the invention
One of purpose of the technology of the present invention is to provide a kind of Novel silencing energy saving pipeline, and this bend pipe structure is simple, it is not necessary to
Adding any sound-absorbing material and can realize preferable soundproof effect, environmental suitability is strong, and it can be carried out according to characteristic frequency
Design, has higher design frequency band acoustic characteristics.For tubings such as smeltery, oil plant, coal-burning power plant's heat exchange, removable
Original pipeline silencer, reduces voltage loss.
The two of the purpose of the technology of the present invention are that the flow field combining in pipeline when interfering the design of noise elimination lateral respectively organized by bend pipe
Characteristic, makes each group of branches pipeline have current-sharing, current stabilization effect while realizing eliminating the noise, and then improves tubing interior flow field
Characteristic, reduces pipeline flow resistance, it is achieved energy-conservation.
The three of the purpose of the present invention are the regulation effects by energy-saving silencing pipeline, improve the turbulent shape of air-flow in pipeline
State, reduces the secondary gas flow noise that air current flow is caused, reduces the vibration that turbulent air flow is induced simultaneously.
Technical scheme is as follows:
A kind of energy-saving silencing pipeline, including entrance, pipe main body and pipe outlet；Wherein pipe main body is that pipeline enters
Mouthful and pipe outlet between part, pipe main body includes one or more pipeline group, and pipeline group is independent by two
Lateral forms；Sound wave is divided into different path at two laterals entering pipeline group this pipeline group of tailing edge and propagates,
The last odd-multiple that phase contrast is π of the sound wave that two laterals spread out of when spreading out of this pipeline group and converging.
Acoustic pressure extreme value in acoustic pressure spectrum curve at described energy-saving silencing pipeline, the number of pipeline group and entrance
Number is identical.
Described energy-saving silencing pipeline, the continuous passage that lateral is made up of polylith wallboard.
Described energy-saving silencing pipeline, entrance and pipe outlet are provided with connection member.
Described energy-saving silencing pipeline, it is characterised in that connection member is flange.
The energy-saving silencing pipeline that the present invention provides, this pipeline configuration is simple, it is not necessary to adding any sound-absorbing material can be real
The highest soundproof effect, environmental suitability is strong.Energy-saving silencing pipeline, while realizing duct attenuation, improves pipe interior stream
Field characteristic, reduces aeration resistance and realizes energy-conservation, reduces in pipeline the quadratic noise caused by air current flow and vibration simultaneously.
The energy-saving silencing pipeline that the present invention provides based on lateral along the central axial length of air-flow according to bend pipe noise
Acoustic pressure extreme frequencies (counteracting frequency) design of porch, has been reached the effect eliminated the noise, has utilized branch simultaneously by sound wave interference
Pipeline, by sound wave and airflow diversion, serves the effect eliminating eddy flow, further up to steady flow result.
The technology of the present invention relates to multiple operation principle, specific as follows:
Operation principle one: the noise that fan operation produces, propagates along tubing, interferes noise elimination lateral to enter at each group
Mouth is divided into two row, and sound wave produces interference in lateral outlet after propagating different distance in two laterals, if two row
The amplitude of sound wave is identical, and at the area of space of the odd-multiple that phase contrast is π, two row sound waves will be cancelled out each other.
Operation principle two: air-flow flow field in pipeline is extremely complex, especially in pipe bent position, the speed of air-flow and pressure
Significant change will occur, bigger barometric gradient and speed difference occur, turbulization panting action is also attended by depositing of maelstrom
, increase the aeration resistance of pipeline, produce bigger quadratic noise easy induced vibration.Energy-saving silencing pipeline each component arm
Road passes through certain current balance function, can improve pipeline flow field, eliminates turbulent flow phenomenon so that manifold pressure is relative with velocity flow profile
Uniformly, the aeration resistance of pipeline is reduced, it is achieved energy-conservation.Along with the improvement of pipeline flow field, the turbulent flow of air-flow, panting action fall
Low, secondary recycling and vibration that air-flow velocity is induced weaken the most therewith.
Operation principle three: it is less that pipeline interferes noise elimination to be affected by air velocity, and owing to not using any sound-absorbing material,
Therefore structure is relatively easy, and volume is little, and environmental suitability is higher, it is to avoid make because installing silencing apparatus additional in traditional noise reduction schemes
Obtain the problem that voltage loss increases, greatly improve energy saving.
The present invention compared with prior art has the beneficial effect that:
1, energy-saving damping inner-walls of duct need not add any sound-absorbing material and i.e. can reach higher acoustic attenuation performance, structure letter
Single, volume is little, and adaptive capacity to environment is strong, and is affected little by air-flow.
2, in energy-saving damping pipeline, each group interferes the application of noise elimination lateral to interfere noise-cancelling theory, can enter according to characteristic frequency
Row design, has preferably design frequency band acoustic characteristics.
3, each group of energy-saving damping pipeline interferes the design of noise elimination pipeline, utilizes and be respectively in charge of while reaching soundproof effect
Road, by airflow diversion, improves pipe interior flow field, reduces aeration resistance, it is achieved be energy-conservation.
4, each group interferes noise elimination pipeline to be combined, and improves pipe interior flow field, plays the effect of current-sharing current stabilization, reduces
The secondary gas flow noise induced because of turbulent air flow and vibration.
5, the technology of the present invention achieves the unification of duct attenuation noise reduction and energy-saving vibration-reduction first.
6, the technology of the present invention realizes not method for designing according to conventional muffler first, it is achieved ventilating noise-elimination, improves logical
The service life of wind pipeline.
The energy-saving damping pipeline that the present invention provides creatively uses interferes the principle design eliminated the noise lateral to reach
Noise elimination effect, utilizes again the design of lateral to reach the effect of energy-conservation current stabilization on the basis of eliminating the noise simultaneously, will eliminate the noise with
Current stabilization is unified dexterously.Present configuration simply acts on substantially, reaches the effect of steady flow condition while noise elimination can be fully achieved
Really.
Accompanying drawing explanation
Fig. 1 is the energy-saving silencing piping schematic described in the embodiment of the present invention 1；
Fig. 2 is the energy-saving silencing pipe branch pipe design schematic diagram described in the embodiment of the present invention 1；
Fig. 3 is the energy-saving silencing piping schematic described in the embodiment of the present invention 2；
Fig. 4 is the energy-saving silencing piping schematic described in the embodiment of the present invention 3；
In figure 1 above, Fig. 3 and Fig. 4,1 is entrance, and 2 is pipe main body, and 21 is the first pipeline group, and 22 is the second pipe
Road group, 3 is pipe outlet, and 4 is connection member.
Detailed description of the invention:
The energy-saving silencing pipeline provided the present invention below in conjunction with accompanying drawing is further described.
Embodiment 1
As it is shown in figure 1, the energy-saving silencing piping schematic provided for the present invention, including entrance 1, pipe main body 2 with
Pipe outlet 3；Wherein pipe main body 2 is the part between entrance 1 and pipe outlet 3, and pipe main body 2 includes a pipeline
Group, pipeline group is made up of two independent laterals；Sound wave is entering pipeline group tailing edge two each laterals of this pipeline group
It is divided into different path to propagate, finally the phase place of the sound wave that two laterals spread out of when spreading out of this pipeline group and converging
Difference is the odd-multiple of π.The design principle of the present embodiment is as follows:
As in Fig. 2 pipeline group, parallel branch pipeline is set.If the length of two laterals is respectively l1And l2, pipeline section
Amass and beIncident acoustic wave is divided into two-way at branch point A, propagates l respectively1And l2After, converge at branch point B.If sound
Propagate the difference odd-multiple equal to half-wavelength of distance, i.e.
The odd-multiple that phase contrast is π of so two sound waves, therefore will cancel out each other after superposition at B.Remember corresponding frequency
For fn, i.e.
It follows that be f for frequencynSound wave, it is impossible to being blazed abroad by this lateral, this frequency is supporting
Disappear frequency.
Embodiment 2
As it is shown on figure 3, the energy-saving silencing piping schematic provided for the present embodiment, it is the improvement on the basis of embodiment 1,
Wherein the corner of lateral is cambered design, the most beneficially steady flow condition, plays energy-conserving action；Entrance and pipe
Being provided with connection member 4 in road outlet, this connection member is adpting flange, and the connection further facilitating pipeline and other equipment should
With.
Embodiment 3
Utilize the energy-saving damping pipe applications that the present invention provides in power plant's ventilating system, and be arranged on fan wind inleting tube road system
System plays energy-saving silencing effect.Through in-site measurement, the installation place sound pressure frequency response curve of energy-saving damping pipeline relates to two sound
Pressure crest frequency, the most described energy-saving silencing pipeline (as shown in Figure 4) includes two groups of pipeline group, the respectively first pipeline group 21 He
Second pipe group 22, each pipeline group corresponds to a peak sound pressure frequency, and wherein the first pipeline group 21 is using 230Hz as counteracting
Frequency, second pipe group 22 is using 460Hz as offsetting frequency.The continuous passage that each lateral is made up of polylith wallboard, respectively
Group of branches pipeline is with certain radian and inclination angle.
During energy-saving damping pipeline work, blower fan direction propagate the noise come, interfere noise elimination lateral to enter from each group
Mouth is divided into two row sound waves, interferes negative function after the lateral of each pipeline group in noise exit, and frequency is offset in design
Noise at rate will be completely counterbalanced by, it is achieved the noise elimination noise reduction of pipeline.Air-flow flows into each lateral, equal due to each lateral
Stream effect, it is to avoid the unfavorable flow field defects such as eddy current occur so that in pipeline, flow velocity and pressure distribution are uniform, reduce flow resistance,
Decrease quadratic noise and vibration that air-flow current stabilization causes, it is achieved that energy-conservation and vibration damping.
In the present embodiment, its noise reduction at 230 and 460Hz is respectively 17.8dB and 18dB, and pipeline sound transmission loss is about
20dB, an alternative Daepori leads to dissipative muffler.In energy-saving damping pipeline access conduit system, under design conditions, pipeline is originally
The body pressure loss reduces half, and the contrast tubing containing acoustic filter, amount of energy saving is about 15%.
Claims (5)
1. an energy-saving silencing pipeline, including entrance, pipe main body and pipe outlet；Wherein pipe main body is entrance
And the part between pipe outlet, it is characterised in that pipe main body includes one or more pipeline group, pipeline group is by two
Individual independent lateral composition；Sound wave is divided into different path at two laterals entering pipeline group this pipeline group of tailing edge and enters
Row is propagated, the odd-multiple that finally phase contrast of the sound wave that two laterals spread out of is when spreading out of this pipeline group and converging.
Energy-saving silencing pipeline the most according to claim 1, it is characterised in that acoustic pressure at the number of pipeline group and entrance
Acoustic pressure extreme value number in spectrum curve is identical.
Energy-saving silencing pipeline the most according to claim 1, it is characterised in that the company that lateral is made up of polylith wallboard
Continuous passage.
Energy-saving silencing pipeline the most according to claim 1, it is characterised in that entrance and the company of being provided with on pipe outlet
Relay part.
Energy-saving silencing pipeline the most according to claim 4, it is characterised in that connection member is flange.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610530255.8A CN106015818B (en) | 2016-07-06 | 2016-07-06 | A kind of energy-saving silencing pipeline |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610530255.8A CN106015818B (en) | 2016-07-06 | 2016-07-06 | A kind of energy-saving silencing pipeline |
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| Publication Number | Publication Date |
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| CN106015818A true CN106015818A (en) | 2016-10-12 |
| CN106015818B CN106015818B (en) | 2018-12-25 |
Family
ID=57108064
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610530255.8A Active CN106015818B (en) | 2016-07-06 | 2016-07-06 | A kind of energy-saving silencing pipeline |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106352516A (en) * | 2016-10-31 | 2017-01-25 | 珠海格力电器股份有限公司 | Variable air volume terminal and air conditioner |
| CN107631106A (en) * | 2017-08-24 | 2018-01-26 | 江西泰豪军工集团有限公司 | Discharge duct and its sound reduction method |
| CN107761620A (en) * | 2017-10-24 | 2018-03-06 | 徐工集团工程机械有限公司 | Air channel part and road cleaner |
| CN109341052A (en) * | 2018-10-18 | 2019-02-15 | 广东美的制冷设备有限公司 | Silencer for air conditioner and air conditioner |
| CN111426045A (en) * | 2020-02-28 | 2020-07-17 | 青岛海尔空调电子有限公司 | Noise reduction air duct assembly for air duct machine and design method thereof |
| CN112503024A (en) * | 2020-11-02 | 2021-03-16 | 北京朗新明环保科技有限公司南京分公司 | Energy-saving and comprehensive noise-reducing fan pipeline and transformation method |
| WO2021104211A1 (en) * | 2019-11-29 | 2021-06-03 | 维沃移动通信有限公司 | Electronic device |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106352516A (en) * | 2016-10-31 | 2017-01-25 | 珠海格力电器股份有限公司 | Variable air volume terminal and air conditioner |
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| CN112503024A (en) * | 2020-11-02 | 2021-03-16 | 北京朗新明环保科技有限公司南京分公司 | Energy-saving and comprehensive noise-reducing fan pipeline and transformation method |
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|---|---|
| CN106015818B (en) | 2018-12-25 |
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