CN110748506A - Noise elimination device for turbocharger - Google Patents
Noise elimination device for turbocharger Download PDFInfo
- Publication number
- CN110748506A CN110748506A CN201911089303.4A CN201911089303A CN110748506A CN 110748506 A CN110748506 A CN 110748506A CN 201911089303 A CN201911089303 A CN 201911089303A CN 110748506 A CN110748506 A CN 110748506A
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- Prior art keywords
- hole
- pipe
- noise elimination
- turbocharger
- muffler
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- 230000008030 elimination Effects 0.000 title claims description 31
- 238000003379 elimination reaction Methods 0.000 title claims description 31
- 230000008878 coupling Effects 0.000 claims description 7
- 238000010168 coupling process Methods 0.000 claims description 7
- 238000005859 coupling reaction Methods 0.000 claims description 7
- 230000008676 import Effects 0.000 claims description 4
- 230000030279 gene silencing Effects 0.000 abstract description 27
- 230000003584 silencer Effects 0.000 abstract description 10
- 230000005540 biological transmission Effects 0.000 abstract description 9
- 230000002238 attenuated effect Effects 0.000 abstract description 4
- 230000000694 effects Effects 0.000 description 7
- 230000009467 reduction Effects 0.000 description 5
- 238000004088 simulation Methods 0.000 description 4
- 238000013016 damping Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000001743 silencing effect Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/663—Sound attenuation
- F04D29/665—Sound attenuation by means of resonance chambers or interference
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/66—Combating cavitation, whirls, noise, vibration or the like; Balancing
- F04D29/661—Combating cavitation, whirls, noise, vibration or the like; Balancing especially adapted for elastic fluid pumps
- F04D29/663—Sound attenuation
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Supercharger (AREA)
Abstract
The invention discloses a silencing device for a turbocharger, which comprises an inlet pipe, a cone-shaped silencing assembly coaxially connected to the right end of the inlet pipe, a first column-shaped silencing assembly, a second column-shaped silencing assembly and an outlet pipe, wherein the first column-shaped silencing assembly and the second column-shaped silencing assembly are sequentially coaxially connected to the right end of the cone-shaped silencing assembly, the outlet pipe is coaxially connected to the right end of the second column-shaped silencing assembly, the cone-shaped silencing assembly is used for silencing within the frequency range of 2300Hz to 4830Hz, and the first column-shaped silencing assembly and the second column-shaped silencing assembly are used for silencing within the frequency range of. The silencer has the advantages of simple and compact structure, wide silencing range and large silencing quantity, the transmission loss amplitude in the frequency range of 460Hz to 4830Hz reaches more than 20dB, and the intake noise of the medium-high frequency broadband turbocharger is effectively attenuated.
Description
Technical Field
The invention relates to the technical field of noise elimination and reduction, in particular to a noise elimination device for a turbocharger.
Background
The engine is introduced into the turbocharger, so that the dynamic property and the fuel economy of the automobile can be improved, but the noise generated by the turbocharger during high-frequency vibration and high-speed rotation can greatly affect the service life and the comfort of the automobile, and the frequency range of the generated noise is mainly concentrated in the range of 600 Hz-3000 Hz. In operation, a wide noise band is generated in this frequency band, so that a wide-frequency muffler in this frequency range is required for the turbocharger intake system to eliminate its characteristic noises such as Hiss sound, blowoff sound, synchronization and subsynchronization, and a sufficient amount of sound attenuation is required in this frequency band. The simple resistive muffler cannot completely eliminate the broadband noise of the turbocharger because the muffling amplitude of the simple resistive muffler is limited in the full frequency range. In addition, the installation space of the current engine compartment is more and more miniaturized, and the space size of the silencer is more and more required.
The muffling principle of the perforated muffler is similar to a Helmholtz resonance effect, the impedance effect generated when sound waves pass through the through holes of the perforated pipe can obviously attenuate the sound waves with the same frequency as the resonance frequency of the resonant cavity chamber, the muffling capacity of medium-high frequency noise is good, and the muffling frequency band is wide. The silencing effect of full-frequency high silencing quantity is realized by controlling the number of resonant cavities and the number, diameter and depth of through holes. In recent years, transmission loss research on a perforated pipe silencing structure is increasing, and JW Sullivan et al establish an acoustic impedance model to find that the acoustic velocity has a large influence on the acoustic impedance. K. Narayana Rao et al propose empirical formulas for calculating the acoustic resistivity of a perforated panel. The Convergo analysis designs an empirical acoustic resistivity model of the effect of perforation rate, air flow parameters and frequency on acoustic impedance.
However, the above studies are all based on single-chamber perforated structures. The traditional single-cavity resonance silencer can only inhibit the noise of a narrow frequency band, cannot attenuate the medium-high frequency noise of a wide frequency band, has poor silencing capability, and has the problems of large structural size, complex structure and the like.
Disclosure of Invention
In order to solve the defects of the prior art, the invention provides the silencer for the turbocharger, so that the transmission loss amplitude in the frequency range of 460Hz to 4830Hz reaches more than 20dB, and the intake noise of the medium-high frequency broadband turbocharger is effectively attenuated.
The technical effect to be achieved by the invention is realized by the following scheme: the utility model provides a noise eliminator for turbo charger, includes the awl type noise elimination subassembly of import pipe, coaxial coupling in proper order at the awl type noise elimination subassembly of import pipe right-hand member, coaxial coupling in proper order in the first column type noise elimination subassembly and the second column type noise elimination subassembly of awl type noise elimination subassembly right-hand member and the coaxial coupling in the outlet pipe of second column type noise elimination subassembly right-hand member, the awl type noise elimination subassembly is used for the noise elimination in 2300Hz ~4830Hz frequency range, first column type noise elimination subassembly and second column type noise elimination subassembly are used for the noise elimination in 460Hz ~2300Hz frequency range.
Preferably, the cone-shaped noise elimination assembly comprises a first central pipe and a plurality of first resonant cavities which are annularly arranged on the outer layer of the first central pipe and have the volume increasing in an equal proportion from left to right, and the first central pipe is provided with a first through hole.
Preferably, the number of the first resonant cavities is 4.
Preferably, the first through hole is a rectangular through hole.
Preferably, the first cylindrical silencing assembly comprises a second central pipe and a second resonant cavity annularly arranged on the outer layer of the second central pipe, and the second central pipe is provided with a second through hole.
Preferably, the second column type noise elimination assembly comprises a third central pipe, a fourth central pipe arranged on the outer layer of the third central pipe in a surrounding mode and a third resonant cavity arranged on the outer layer of the third central pipe in a surrounding mode, the third central pipe is provided with a third through hole, and the fourth central pipe is provided with a fourth through hole.
Preferably, the diameter of the fourth through hole is larger than the diameter of the third through hole.
Preferably, the second through hole, the third through hole and the fourth through hole are all circular through holes.
Preferably, the first resonant cavity, the second resonant cavity and the third resonant cavity are separated by cavity walls with the same wall thickness to form independent cavities.
Preferably, the inlet pipe and the outlet pipe are fixedly connected to an air inlet pipe of the turbocharger through flanges.
The invention has the following advantages:
the silencer provided by the embodiment of the invention has the advantages of simple and compact structure, wide silencing range and large silencing quantity, the transmission loss amplitude in the frequency range of 460 Hz-4830 Hz reaches more than 20dB, and the intake noise of the medium-high frequency broadband turbocharger is effectively attenuated.
Drawings
Fig. 1 is a schematic plan view of a muffler device for a turbocharger according to the present invention;
FIG. 2 is a schematic cross-sectional view of a muffler assembly for a turbocharger of the present invention;
FIG. 3 is a mesh division of a simulation model of a muffler assembly for a turbocharger of the present invention;
fig. 4 is a graph showing a simulation of a sound transmission loss curve of a muffler device for a turbocharger according to the present invention.
Detailed Description
The invention is described in detail below with reference to the drawings, wherein examples of the embodiments are shown in the drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.
In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.
Furthermore, the terms "first", "second", "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," "disposed," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the interconnection of two elements or through the interaction of two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
Referring to fig. 1 and 2, an embodiment of the present invention provides a muffler device for a turbocharger, which is connected to an intake duct of the turbocharger, and includes an intake pipe 100, a cone-shaped muffler assembly 200 coaxially connected to a right end of the intake pipe 100, a first cylindrical muffler assembly 300 and a second cylindrical muffler assembly 400 coaxially connected to a right end of the cone-shaped muffler assembly 200 in sequence, and an outlet pipe 500 coaxially connected to a right end of the second cylindrical muffler assembly 400, wherein the cone-shaped muffler assembly 200 is used for muffling within a frequency range of 2300Hz to 4830Hz, and the first cylindrical muffler assembly 300 and the second cylindrical muffler assembly 400 are used for muffling within a frequency range of 460Hz to 2300 Hz. The silencer provided by the embodiment of the invention has the advantages of simple and compact structure, wide silencing range and large silencing quantity, the transmission loss amplitude in the frequency range of 460 Hz-4830 Hz reaches more than 20dB, and the intake noise of the medium-high frequency broadband turbocharger is effectively attenuated.
Specifically, the cone-shaped muffling assembly 200 includes a first central tube 210 and a plurality of first resonant cavities 220 (the plurality of first resonant cavities 220 form a cone-shaped resonant cavity) arranged around the outer layer of the first central tube 210, wherein the volumes of the first resonant cavities are increased in an equal proportion from left to right, and a first through hole 230 is formed in the first central tube 210. Because the space in the conical resonant cavity is relatively small, the noise elimination frequency value is high, and the noise elimination device can be used for noise elimination within the frequency range of 2300Hz to 4830 Hz.
In the embodiment of the present invention, too many chambers of the first resonant cavity 220 may cause a reduction in frequency band, and too few chambers may cause a discontinuity in sound attenuation frequency, so the number of the first resonant cavities 220 is preferably 4, the volume of each first resonant cavity 220 from left to right increases in an equal proportion to form a cone structure, and the specific size of the volume of the first resonant cavity 220 may be designed into different specifications according to different sound attenuation required frequency ranges. The first through hole 230 is preferably a rectangular through hole, which can be designed according to the frequency range required for noise reduction (for example, three spaced rectangular through holes are formed on the first central tube 210 of each first resonant cavity 220 as shown in fig. 2), and since the rectangular through hole is easier to machine than the circular through hole, and the noise reduction frequency is related to the perforation rate, the rectangular through hole and the circular through hole provide the perforation area, and the perforation rate is the ratio of the perforation area to the total area of the perforated pipe.
The first cylindrical muffler assembly 300 comprises a second central pipe 310 and a second resonant cavity 320 annularly arranged on the outer layer of the second central pipe 310, and the second central pipe 310 is provided with a second through hole 330; the second cylindrical noise elimination assembly 400 comprises a third center pipe 410, a fourth center pipe 420 annularly arranged on the outer layer of the third center pipe 410, and a third resonant cavity 430 annularly arranged on the outer layer of the third center pipe 410, wherein the third center pipe 410 is provided with a third through hole 440, and the fourth center pipe 420 is provided with a fourth through hole 450. Impedance mismatch effect is caused by connecting the central pipes with the through holes in series and in parallel, and compared with the combination of Helmholtz resonators, the damping frequency is relatively low, and the damping device can be used for damping within the frequency range of 460Hz to 2300 Hz. It should be understood that the second center tube 310 and the third center tube 410 may be integrally formed together or may be separately formed and then fixed together.
In the embodiment of the present invention, the second through hole 330, the third through hole 440, and the fourth through hole 450 are preferably all circular through holes, and the diameter of the fourth through hole 450 is preferably greater than the diameter of the third through hole 440, so that the low-frequency lower limit cut-off frequency can be widened. It should be understood that the second through hole 330, the third through hole 440 and the fourth through hole 450 can be designed to have different diameters according to different frequency ranges of sound attenuation requirements.
In the embodiment of the present invention, for convenience of manufacturing, the first resonant cavity 220, the second resonant cavity 320 and the third resonant cavity 430 (corresponding to six cavities) are preferably separated by cavity walls with the same wall thickness to form independent cavities, the inlet pipe 100, the first central pipe 210, the second central pipe 310, the third central pipe 410 and the outlet pipe 500 are preferably integrally formed, and the pipe thicknesses of the inlet pipe 100, the first central pipe 210, the second central pipe 310, the third central pipe 410, the fourth central pipe 420 and the outlet pipe 500 are preferably the same as the wall thicknesses of the resonant cavities.
In the embodiment of the present invention, the inlet pipe 100 and the outlet pipe 500 may be fixedly connected to an inlet duct of a turbocharger through flanges, but are not limited thereto. The material of the silencing device is stainless steel or carbon steel, and the conical silencing component 200 and the cylindrical silencing component can be formed separately and then combined into a whole, but the silencing device is not limited to the above.
The silencer is arranged in an air inlet pipeline of a turbocharger, when an engine runs, airflow passes through the silencer without obstruction, when sound waves pass through a through hole of a central pipe, the through hole and a resonant cavity form an elastic vibration system, when the frequency of the internal sound waves of the air inlet pipeline is the same as the natural frequency of the resonant cavity vibration system, the system generates a resonance effect, so that the movement speed of an air column in the through hole is accelerated, the friction between air and the wall of the cavity is intensified, sound energy is converted into heat energy to the maximum extent, and the silencing effect on noise in the air inlet pipeline is the maximum.
According to the embodiment of the invention, the acoustic performance of the silencer is subjected to simulation analysis through finite element simulation software COMSOL Muitiphy 5.3a, and the control noise reduction effect of the silencer is verified. Please refer to fig. 3, which is a schematic diagram of meshing the air space inside the muffler device. The medium of the fluid domain is air, an air domain inlet and an air domain outlet are arranged, and the transmission loss of the model is calculated by using an acoustic-solid coupling module in software. Referring to FIG. 4, which is a simulation result diagram of transmission loss of the muffler device, the transmission loss amplitude in the frequency range of 460Hz to 4830Hz is above 20 dB.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the embodiments of the present invention and not for limiting the same, and although the embodiments of the present invention are described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the embodiments of the present invention, and these modifications or equivalent substitutions cannot make the modified technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (10)
1. The utility model provides a noise eliminator for turbo charger, its characterized in that, includes the awl type noise elimination subassembly of import pipe, coaxial coupling at the import pipe right-hand member, in proper order coaxial coupling at the first cylindricality noise elimination subassembly and the second cylindricality noise elimination subassembly of awl type noise elimination subassembly right-hand member and the coaxial coupling at the outlet pipe of second cylindricality noise elimination subassembly right-hand member, the awl type noise elimination subassembly is used for the noise elimination in 2300Hz ~4830Hz frequency range, first cylindricality noise elimination subassembly and second cylindricality noise elimination subassembly are used for the noise elimination in 460Hz ~2300Hz frequency range.
2. The muffler device for a turbocharger according to claim 1, wherein the cone-shaped muffler assembly comprises a first central pipe and a plurality of first resonant cavities which are annularly arranged on the outer layer of the first central pipe and have the volume increasing from left to right in an equal proportion, and the first central pipe is provided with a first through hole.
3. A muffler assembly for a turbocharger as claimed in claim 2, wherein the number of said first resonant cavities is 4.
4. The muffler apparatus for a turbocharger according to claim 2, wherein the first through-hole is a rectangular through-hole.
5. The muffler apparatus of claim 2, wherein the first cylindrical muffler assembly comprises a second center pipe and a second resonant cavity surrounding the second center pipe, and the second center pipe defines a second through hole.
6. The muffler device for a turbocharger of claim 5, wherein the second cylindrical muffler assembly comprises a third center pipe, a fourth center pipe annularly arranged on the outer layer of the third center pipe, and a third resonant cavity annularly arranged on the outer layer of the third center pipe, the third center pipe is provided with a third through hole, and the fourth center pipe is provided with a fourth through hole.
7. The muffler apparatus for a turbocharger according to claim 6, wherein the diameter of the fourth through hole is larger than the diameter of the third through hole.
8. The muffler apparatus for a turbocharger according to claim 6, wherein the second through-hole, the third through-hole, and the fourth through-hole are circular through-holes.
9. The muffler apparatus of claim 6, wherein the first resonator, the second resonator and the third resonator are separated by a wall having the same wall thickness to form separate chambers.
10. The muffler assembly for a turbocharger of claim 1, wherein the inlet pipe and the outlet pipe are fixedly coupled to an intake duct of the turbocharger by flanges.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201911089303.4A CN110748506B (en) | 2019-11-08 | Be used for turbo charger muffler device of a muffler |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201911089303.4A CN110748506B (en) | 2019-11-08 | Be used for turbo charger muffler device of a muffler |
Publications (2)
Publication Number | Publication Date |
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CN110748506A true CN110748506A (en) | 2020-02-04 |
CN110748506B CN110748506B (en) | 2024-10-22 |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112318876A (en) * | 2020-10-12 | 2021-02-05 | 李冉 | 3D prints silencing device |
CN112502872A (en) * | 2020-11-17 | 2021-03-16 | 宁波丰茂远东橡胶有限公司 | Noise reduction device for air outlet system of turbocharger |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105484828A (en) * | 2014-10-01 | 2016-04-13 | 通用汽车环球科技运作有限责任公司 | Silencer |
CN105822469A (en) * | 2016-05-11 | 2016-08-03 | 安徽江淮汽车股份有限公司 | Noise abatement device of engine air inlet system |
JP2017096114A (en) * | 2015-11-19 | 2017-06-01 | 小島プレス工業株式会社 | Muffler for vehicle |
CN207315551U (en) * | 2017-09-13 | 2018-05-04 | 安徽江淮汽车集团股份有限公司 | A kind of noise elimination structure of gas handling system |
CN207740102U (en) * | 2017-12-29 | 2018-08-17 | 宜润邦科技(天津)有限公司 | Engine air intake system noise elimination structure and vehicle |
CN210889493U (en) * | 2019-11-08 | 2020-06-30 | 河北亚大汽车塑料制品有限公司 | Noise elimination device for turbocharger |
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105484828A (en) * | 2014-10-01 | 2016-04-13 | 通用汽车环球科技运作有限责任公司 | Silencer |
JP2017096114A (en) * | 2015-11-19 | 2017-06-01 | 小島プレス工業株式会社 | Muffler for vehicle |
CN105822469A (en) * | 2016-05-11 | 2016-08-03 | 安徽江淮汽车股份有限公司 | Noise abatement device of engine air inlet system |
CN207315551U (en) * | 2017-09-13 | 2018-05-04 | 安徽江淮汽车集团股份有限公司 | A kind of noise elimination structure of gas handling system |
CN207740102U (en) * | 2017-12-29 | 2018-08-17 | 宜润邦科技(天津)有限公司 | Engine air intake system noise elimination structure and vehicle |
CN210889493U (en) * | 2019-11-08 | 2020-06-30 | 河北亚大汽车塑料制品有限公司 | Noise elimination device for turbocharger |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112318876A (en) * | 2020-10-12 | 2021-02-05 | 李冉 | 3D prints silencing device |
CN112502872A (en) * | 2020-11-17 | 2021-03-16 | 宁波丰茂远东橡胶有限公司 | Noise reduction device for air outlet system of turbocharger |
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