CN113763914A - Spiral Helmholtz resonator - Google Patents
Spiral Helmholtz resonator Download PDFInfo
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- CN113763914A CN113763914A CN202111135203.8A CN202111135203A CN113763914A CN 113763914 A CN113763914 A CN 113763914A CN 202111135203 A CN202111135203 A CN 202111135203A CN 113763914 A CN113763914 A CN 113763914A
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- 239000000463 material Substances 0.000 claims description 9
- 229910000746 Structural steel Inorganic materials 0.000 claims description 2
- 239000002131 composite material Substances 0.000 claims description 2
- 239000011347 resin Substances 0.000 claims description 2
- 229920005989 resin Polymers 0.000 claims description 2
- 239000002023 wood Substances 0.000 claims description 2
- 230000005540 biological transmission Effects 0.000 abstract description 24
- 230000008859 change Effects 0.000 abstract description 4
- 230000008030 elimination Effects 0.000 abstract description 4
- 238000003379 elimination reaction Methods 0.000 abstract description 4
- 238000000034 method Methods 0.000 abstract description 3
- 238000002834 transmittance Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 230000030279 gene silencing Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 229920000122 acrylonitrile butadiene styrene Polymers 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000000644 propagated effect Effects 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/172—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using resonance effects
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- Acoustics & Sound (AREA)
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- Soundproofing, Sound Blocking, And Sound Damping (AREA)
- Building Environments (AREA)
Abstract
The invention provides a spiral Helmholtz resonator, which comprises a Helmholtz resonator neck pipe B, a Helmholtz resonator cavity structure C and a spiral blade arranged in the cavity, wherein the spiral blade and the cavity are integrally formed, the Helmholtz resonator cavity structure C is connected with the Helmholtz resonator neck pipe B, and the Helmholtz resonator neck pipe B is vertically connected with a main pipe A. The technical problem of prior art's helmholtz resonator low frequency range noise elimination ability not enough is solved, provides a screw-tutz resonator, through the inside method that changes the cavity, obtains under the prerequisite that does not change overall dimension, guarantees that resonant frequency does not change to the helmholtz resonator that transmission loss is strong.
Description
Technical Field
The invention relates to a spiral Helmholtz resonator, and belongs to the technical field of noise control devices.
Background
The pipeline system has very wide application background in the fields of aerospace, ships, chemical engineering, water conservancy and the like. Noise propagation and noise control of sound waves in pipes is a very important research. It is common practice to use the acoustic resonance characteristics of helmholtz resonators to cancel noise. Through setting up traditional helmholtz resonant cavity structural parameters, when the sound wave propagated to pipeline and resonator neck pipe boundary surface, because the change of interface acoustic impedance, the sound wave got into the cavity of resonator, can arouse the vibration of resonator to produce resonance, can be effectual with the energy consumption of sound wave near resonant frequency this moment.
Generally, helmholtz resonators control the resonance frequency and the magnitude of the transmission loss by varying the neck and cavity dimensions. The Helmholtz resonator has small size, high resonance frequency and strong transmission loss; large size, low resonance frequency and weak transmission loss. In the precision field, a pipeline system is compact in arrangement and strict in size control, noise has the characteristic of strong low-frequency transmission capability, low-frequency noise elimination cannot be realized in a small size, and noise transmission cannot be effectively inhibited in a large size.
Disclosure of Invention
In order to solve the technical problem mentioned in the background art that the helmholtz resonator in the prior art has insufficient noise elimination capability in the low frequency range, the invention provides a spiral helmholtz resonator, and the helmholtz resonator which ensures that the resonance frequency is not changed and the transmission loss is strong is obtained on the premise of not changing the whole size by changing the interior of the cavity.
The invention provides a spiral Helmholtz resonator, which comprises a Helmholtz resonator neck pipe B, a Helmholtz resonator cavity structure C and spiral blades arranged in a cavity, wherein the spiral blades and the cavity are integrally formed, the Helmholtz resonator cavity structure C is connected with the Helmholtz resonator neck pipe B, and the Helmholtz resonator neck pipe B is vertically connected with a main pipe A.
Preferably, the Helmholtz resonator neck B and Helmholtz resonator cavity structure C are both cylindrical, and the Helmholtz resonator cavity structure C has a diameter greater than the diameter of Helmholtz resonator neck B.
Preferably, the outer diameter of the helical blade is the same as the inner diameter of the Helmholtz resonator cavity structure C, and the inner diameter of the helical blade is larger than the inner diameter of the Helmholtz resonator neck tube B.
Preferably, the helical blade longitudinal height is the same as the helmholtz resonator cavity structure C height.
Preferably, the helmholtz resonator cavity structure C is open only at the junction with the helmholtz resonator neck B, with the sound wave incident end of the helmholtz resonator cavity structure C communicating with the helmholtz resonator neck B.
Preferably, the helical blade is provided in two turns.
Preferably, the pitch of both turns of the helical blade is 25 mm.
Preferably, the pitch of the first turn of the helix of the helical blade is 35mm and the pitch of the second turn of the helix is 15 mm.
Preferably, the duct a, the helmholtz resonator neck B and the helmholtz resonator cavity structure C are all made of hard boundary materials.
Preferably, the duct a, the helmholtz resonator neck B and the helmholtz resonator cavity structure C are all made of structural steel, resin, wood or composite material.
The spiral Helmholtz resonator has the beneficial effects that:
(1) because the spiral structure is used, the spiral resonant cavity with the same size is adopted to replace the traditional Helmholtz resonant cavity, when sound waves enter the cavity through the neck pipe, the spiral structure is added, the propagation distance of the sound waves in the cavity can be increased, namely, the obstruction of the sound waves in the transmission process is increased, so that the impedance inside the cavity can be increased, the transmission loss under the same resonance frequency is improved, the silencing capability of the Helmholtz resonator is enhanced, and the silencing capability of a large volume or a plurality of traditional Helmholtz resonators during working can be achieved under the condition of not changing the volume.
(2) The spiral Helmholtz resonator can increase the transmission loss without changing the volume of the resonant cavity, and the transmission coefficient shows that the effective working frequency band of the resonator can be widened and the acoustic performance of the whole structure can be improved.
(3) The spiral structural material adopted by the invention has the advantages of wide selection, simple manufacture, low cost, convenient assembly and wide application prospect.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention.
In the drawings:
FIG. 1 is a schematic diagram of a conventional Helmholtz resonator;
FIG. 2 is a graphical representation of the transmission loss, transmittance as a function of acoustic frequency for the conventional Helmholtz resonator of FIG. 1;
FIG. 3 is a structural view of a helical Helmholtz resonator according to the present invention
FIG. 4 is a graphical representation of the transfer loss of the helical Helmholtz resonator of FIG. 3 versus the frequency of the sound waves;
FIG. 5 is a schematic view of adjusting the pitch of the helix;
FIG. 6 is a graphical representation of the transmission loss of the spiral Helmholtz resonator of FIG. 5 as a function of acoustic frequency;
the structure comprises a 1-Helmholtz resonator cavity structure C, 2-helical blades and a 3-Helmholtz resonator neck tube B.
Detailed Description
The following detailed description of embodiments of the invention is provided in conjunction with the appended drawings:
the first embodiment is as follows: the present embodiment is explained with reference to fig. 1 to 6. The helical helmholtz resonator of this embodiment includes helmholtz resonator neck B3, helmholtz resonator cavity structure C1 and places helical blade 2 inside the cavity, helical blade 2 and cavity integrated printing, helmholtz resonator cavity structure C1 is connected with helmholtz resonator neck B3, helmholtz resonator neck B3 is connected perpendicularly with trunk a.
The Helmholtz resonator neck B3 and Helmholtz resonator cavity structure C1 are both cylindrical, and the Helmholtz resonator cavity structure C1 has a diameter greater than the diameter of Helmholtz resonator neck B3.
The outer diameter of the spiral blade 2 is the same as the inner diameter of a Helmholtz resonator cavity structure C1, and the inner diameter of the spiral blade 2 is larger than the inner diameter of a Helmholtz resonator neck tube B3.
The longitudinal height of the helical blade 2 is the same as the height of the Helmholtz resonator cavity structure C1. The helical blade 2 is provided with two turns.
The helmholtz resonator cavity structure C1 is open only at the junction with the helmholtz resonator neck B3, and the sound wave incident end of the helmholtz resonator cavity structure C1 communicates with the helmholtz resonator neck B3.
Fig. 1 shows a schematic plan view of a conventional helmholtz resonator, which includes a main duct a, a helmholtz resonator neck B, and a helmholtz resonator cavity structure C. Main pipe A and Helmholtz resonator neck B communicate, and Helmholtz resonator neck B and Helmholtz resonator cavity structure C communicate. Wherein, Helmholtz resonator cavity structure C is cylindrical cavity. According to the lumped parameter theory, the resonance frequency of the helmholtz resonator is:
in the formula: c. C0Is the speed of sound in air; scIs the cross street area of the neck pipe; lcIs the length of the connecting tube; vnIs the volume of the cavity. The structural size of the Helmholtz resonator comprises the length and the diameter of a main pipeline A, the length and the diameter of a neck pipe B of the Helmholtz resonator and the length and the diameter of a cavity structure C of the Helmholtz resonator. The length of trunk pipe A is 200mm, and the diameter is 30mm, and Helmholtz resonator neck pipe B is long for 12mm, and the diameter is 12mm, and Helmholtz resonator cavity structure C is long for 50mm, and the diameter is 40 mm. The Helmholtz resonator transmission loss and the change curve of the transmittance with the acoustic wave frequency in FIG. 2 were obtained by placing the integrated unit in the axial direction of the pipe and using simulation software COMSOL Multiphysics. As shown in fig. 2, the red curve represents the variation curve of the transmittance with the acoustic frequency, and the smaller the transmittance is, the more the noise loss is, the better the noise is eliminated. The black curve represents the variation of transmission loss with acoustic frequency, and can be observedThe Helmholtz resonators can effectively eliminate noise within the frequency range of 200 Hz-400 Hz in the whole structure, and the loss of the noise at 300Hz can reach the maximum value close to 35 dB. According to the noise control design specification of industrial enterprises (GBT 50087-2013) implemented in 2013 in China, the all-day noise emission is limited, and the maximum noise emission cannot exceed 70 dB. A transmission loss of 35dB in the noise control domain still does not satisfy the effective control of noise.
Fig. 1 shows a conventional helmholtz resonator, and in the research process of the conventional helmholtz resonator, the problem that the transmission loss is too low when the conventional helmholtz resonator works in a pipeline is found. To solve this problem, the present invention proposes a helical helmholtz resonator for eliminating noise in a pipe as shown in fig. 3. Fig. 3 uses the connection to main duct a of fig. 1, with the dimensions of main duct a, helmholtz resonator neck B3 and helmholtz resonator cavity structure C1 unchanged. By changing the inner part of the cavity, the Helmholtz resonator which ensures that the resonance frequency is not changed and the transmission loss is strong is obtained on the premise of not changing the whole size.
Referring to fig. 3, the present invention is to place a helical blade 2 with an outer diameter of 30mm, an inner diameter of 7mm and two turns of a pitch of 25mm in a cavity structure C1 of a conventional helmholtz resonator. The helical blade 2 placed inside the helmholtz resonator cavity structure C1 can increase the distance of sound wave propagating inside the cavity, increasing the obstruction in the transmission process, thereby increasing the impedance inside the helmholtz resonator cavity structure C1.
As shown in fig. 4, compared with the conventional helmholtz resonator, because the impedance inside the cavity is increased, the transmission loss of the sound wave is increased when the sound wave with the corresponding frequency is transmitted into the cavity, and the transmission loss of the sound wave at 300Hz is increased from 34dB to 39dB, the effect of eliminating the sound wave entering the pipeline within the frequency range of 200Hz to 400Hz can be realized, and it is proved that the working performance of the resonator can be effectively improved by placing the spiral structure inside the cavity.
Referring to fig. 5, the pitch of the helical blade 2 is optimized by increasing the pitch of the first turn of the helix to 35mm and the pitch of the second turn of the helix to 15 mm. The transmission loss of the structure is also calculated by simulation in a way of connecting with the main pipeline A in the figure 1. According to the calculation results, as shown in fig. 6, it is found that the resonance frequency of the spiral resonator is not shifted after the pitch is changed, the effect of eliminating the sound waves entering the pipeline in the frequency range of 200Hz to 400Hz can be realized, the peak value of the transmission loss at 300Hz is as high as 66dB, and the average transmission loss is greatly improved.
The Helmholtz resonator neck B3, Helmholtz resonator cavity structure C1, main duct A, and helical blade 2 are made using hard boundary materials. The hard boundary material is a rigid boundary material, and the normal sound pressure of incident sound waves on the rigid wall is zero. In addition, the hard boundary material, namely the rigid boundary material in the embodiment of the invention adopts ABS plastic, so that the hard boundary material has wide sources, simple manufacture, low cost and convenient assembly.
In summary, the helical helmholtz resonator of the present invention is composed of a helmholtz resonator neck B3, a helmholtz resonator cavity structure C1, and an internal helical blade 2, and determines the geometric parameters of the helical helmholtz resonator according to the helmholtz resonator principle. By utilizing a finite element method, the transfer loss of the spiral Helmholtz resonator is calculated in a simulation mode, and the structure with the optimal noise elimination capacity is determined by adjusting the size of the thread pitch.
The above-mentioned embodiments further explain the objects, technical solutions and advantages of the present invention in detail. It should be understood that the above-mentioned embodiments are only examples of the present invention, and are not intended to limit the present invention, and that the reasonable combination of the features described in the above-mentioned embodiments can be made, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The utility model provides a spiral type helmholtz resonator, its characterized in that includes helmholtz resonator neck B (3), helmholtz resonator cavity structure C (1) and places helical blade (2) inside the cavity, helical blade (2) and cavity integrated into one piece, helmholtz resonator cavity structure C (1) is connected with helmholtz resonator neck B (3), helmholtz resonator neck B (3) is connected with trunk line A is perpendicular.
2. Spiral Helmholtz resonator according to claim 1, characterized in that said Helmholtz resonator neck B (3) and Helmholtz resonator cavity structure C (1) are both cylindrical, the Helmholtz resonator cavity structure C (1) having a diameter larger than the Helmholtz resonator neck B (3).
3. Spiral Helmholtz resonator according to claim 1, characterized in that the outer diameter of the spiral vane (2) is the same as the inner diameter of the Helmholtz resonator cavity structure C (1), the inner diameter of the spiral vane (2) being larger than the inner diameter of the Helmholtz resonator neck B (3).
4. Spiral Helmholtz resonator according to claim 1, characterized in that the longitudinal height of the spiral vane (2) is the same as the height of the Helmholtz resonator cavity structure C (1).
5. Spiral Helmholtz resonator according to claim 1, characterized in that the Helmholtz resonator cavity structure C (1) is open only at the connection with Helmholtz resonator neck B (3), the sound wave incident end of the Helmholtz resonator cavity structure C (1) communicating with Helmholtz resonator neck B (3).
6. Spiral Helmholtz resonator according to claim 1, characterized in that the spiral vane (2) is provided with two turns.
7. Spiral Helmholtz resonator according to claim 6, characterized in that the pitch of both turns of the spiral vane (2) is 25 mm.
8. Spiral Helmholtz resonator according to claim 6, characterized in that the pitch of the first spiral of the spiral vane (2) is 35mm and the pitch of the second spiral is 15 mm.
9. Spiral Helmholtz resonator according to claim 1, characterized in that the main duct A, the Helmholtz resonator neck B (3) and the Helmholtz resonator cavity structure C (1) are made of hard boundary material.
10. Spiral Helmholtz resonator according to claim 1, characterized in that said main duct A, Helmholtz resonator neck B (3) and Helmholtz resonator cavity structure C (1) are made of structural steel, resin, wood or composite material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111135203.8A CN113763914A (en) | 2021-09-27 | 2021-09-27 | Spiral Helmholtz resonator |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111135203.8A CN113763914A (en) | 2021-09-27 | 2021-09-27 | Spiral Helmholtz resonator |
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| CN113763914A true CN113763914A (en) | 2021-12-07 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113539223A (en) * | 2021-07-11 | 2021-10-22 | 哈尔滨工程大学 | Helmholtz sound absorption device |
| CN115780227A (en) * | 2022-10-27 | 2023-03-14 | 西北核技术研究所 | Automatic frequency modulation acoustic effect cabin based on Helmholtz resonant cavity and frequency modulation method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85204952U (en) * | 1985-11-19 | 1987-07-29 | 景尔强 | Rotary silencer |
| CA2094168A1 (en) * | 1993-04-16 | 1994-10-17 | Carl N. Ramjit | Mufflers |
| EP2318672A1 (en) * | 2008-08-14 | 2011-05-11 | Alstom Technology Ltd | Method for adjusting a helmholtz-resonators and a helmholtz-resonator for carrying out the method |
| US20110299981A1 (en) * | 2010-06-04 | 2011-12-08 | Gm Global Technology Operations, Inc. | Induction System with Air Flow Rotation and Noise Absorber for Turbocharger Applications |
| EP2772905A1 (en) * | 2013-02-28 | 2014-09-03 | Honda Motor Co., Ltd. | Helmholtz resonance silencer |
| CN204115188U (en) * | 2014-09-05 | 2015-01-21 | 上海汽车空调配件有限公司 | A kind of for the spirality muffler in automotive air-conditioning system |
| CN106382432A (en) * | 2016-11-22 | 2017-02-08 | 苏州大学 | Helmholtz resonant silencing unit based on maze structure and resonant silencer |
| CN106951623A (en) * | 2017-03-14 | 2017-07-14 | 中国人民解放军海军工程大学 | Pump-jet propulsor model and its method for designing with helmholtz resonance chamber |
| CN107360493A (en) * | 2017-09-07 | 2017-11-17 | 中国船舶重工集团公司第七〇九研究所 | Modified Reed bore muffler |
| CN108022581A (en) * | 2017-12-25 | 2018-05-11 | 中国船舶重工集团公司第七〇九研究所 | A kind of modified Helmholtz resonator |
| CN110503936A (en) * | 2019-08-13 | 2019-11-26 | 安徽建筑大学 | A kind of adjustable sub-wavelength low-frequency sound-absorbing structure |
| CN112489613A (en) * | 2020-12-10 | 2021-03-12 | 镇江华东电力设备制造厂有限公司 | Multilayer noise elimination structural layer disturbance silencer |
-
2021
- 2021-09-27 CN CN202111135203.8A patent/CN113763914A/en active Pending
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85204952U (en) * | 1985-11-19 | 1987-07-29 | 景尔强 | Rotary silencer |
| CA2094168A1 (en) * | 1993-04-16 | 1994-10-17 | Carl N. Ramjit | Mufflers |
| EP2318672A1 (en) * | 2008-08-14 | 2011-05-11 | Alstom Technology Ltd | Method for adjusting a helmholtz-resonators and a helmholtz-resonator for carrying out the method |
| US20110299981A1 (en) * | 2010-06-04 | 2011-12-08 | Gm Global Technology Operations, Inc. | Induction System with Air Flow Rotation and Noise Absorber for Turbocharger Applications |
| EP2772905A1 (en) * | 2013-02-28 | 2014-09-03 | Honda Motor Co., Ltd. | Helmholtz resonance silencer |
| CN204115188U (en) * | 2014-09-05 | 2015-01-21 | 上海汽车空调配件有限公司 | A kind of for the spirality muffler in automotive air-conditioning system |
| CN106382432A (en) * | 2016-11-22 | 2017-02-08 | 苏州大学 | Helmholtz resonant silencing unit based on maze structure and resonant silencer |
| CN106951623A (en) * | 2017-03-14 | 2017-07-14 | 中国人民解放军海军工程大学 | Pump-jet propulsor model and its method for designing with helmholtz resonance chamber |
| CN107360493A (en) * | 2017-09-07 | 2017-11-17 | 中国船舶重工集团公司第七〇九研究所 | Modified Reed bore muffler |
| CN108022581A (en) * | 2017-12-25 | 2018-05-11 | 中国船舶重工集团公司第七〇九研究所 | A kind of modified Helmholtz resonator |
| CN110503936A (en) * | 2019-08-13 | 2019-11-26 | 安徽建筑大学 | A kind of adjustable sub-wavelength low-frequency sound-absorbing structure |
| CN112489613A (en) * | 2020-12-10 | 2021-03-12 | 镇江华东电力设备制造厂有限公司 | Multilayer noise elimination structural layer disturbance silencer |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113539223A (en) * | 2021-07-11 | 2021-10-22 | 哈尔滨工程大学 | Helmholtz sound absorption device |
| CN113539223B (en) * | 2021-07-11 | 2022-05-06 | 哈尔滨工程大学 | Helmholtz sound absorption device |
| CN115780227A (en) * | 2022-10-27 | 2023-03-14 | 西北核技术研究所 | Automatic frequency modulation acoustic effect cabin based on Helmholtz resonant cavity and frequency modulation method |
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Application publication date: 20211207 |