CN113270084A - Noise reduction device and method for aircraft cavity based on sound absorption material - Google Patents
Noise reduction device and method for aircraft cavity based on sound absorption material Download PDFInfo
- Publication number
- CN113270084A CN113270084A CN202110515994.0A CN202110515994A CN113270084A CN 113270084 A CN113270084 A CN 113270084A CN 202110515994 A CN202110515994 A CN 202110515994A CN 113270084 A CN113270084 A CN 113270084A
- Authority
- CN
- China
- Prior art keywords
- cavity
- sound absorption
- aircraft
- sound
- absorption material
- 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.)
- Pending
Links
- 238000010521 absorption reaction Methods 0.000 title claims abstract description 105
- 239000000463 material Substances 0.000 title claims abstract description 73
- 238000000034 method Methods 0.000 title claims abstract description 35
- 230000009467 reduction Effects 0.000 title claims abstract description 35
- 230000010355 oscillation Effects 0.000 claims abstract description 38
- 239000011358 absorbing material Substances 0.000 claims description 38
- 238000012360 testing method Methods 0.000 claims description 5
- 238000003466 welding Methods 0.000 claims description 4
- 238000004026 adhesive bonding Methods 0.000 claims description 2
- 238000002474 experimental method Methods 0.000 claims description 2
- 239000006260 foam Substances 0.000 claims description 2
- 238000012937 correction Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 210000005239 tubule Anatomy 0.000 description 2
- 239000006096 absorbing agent Substances 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000010349 pulsation Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Images
Classifications
-
- 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
- G10K11/162—Selection of materials
-
- 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
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Multimedia (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Abstract
The invention provides a noise reduction device and method for an aircraft cavity based on a sound absorption material, relates to a noise reduction device and method, particularly relates to a noise reduction device and method for an aircraft cavity based on a sound absorption material, and belongs to the technical field of noise reduction. Firstly, calculating to obtain the self-sustaining oscillation frequency of the cavity according to the flight working condition parameters of the aircraft, secondly, selecting the best sound absorption material according to the self-sustaining oscillation frequency and the sound absorption coefficient of different sound absorption materials under the frequency, and finally, fixing the sound absorption material on the cavity of the aircraft as the outer surface of the cavity inner cavity to finish the cavity noise reduction on the premise of keeping the length, depth and width dimensions of the cavity of the aircraft unchanged. The invention solves the technical problems of severe noise and self-sustaining pressure oscillation in the cavity when the aircraft flies. The control of the cavity of the aircraft from two aspects of flow and noise is realized, additional equipment such as an air source and a control system is not introduced, and further the noise is reduced better.
Description
Technical Field
The application relates to a noise reduction device and method, in particular to an aircraft cavity noise reduction device and method based on sound absorption materials, and belongs to the technical field of noise reduction.
Background
Cavities are widely present on modern aircraft. Despite its simple geometry, the flow is quite complex, including a range of unsteady flow characteristics such as high aerodynamic noise, shear-layer instability, turbulence, shock/swell wave interference, shock/shear-layer interference, flow-induced resonance, and turbulence. Therefore, the measure of noise and flow comprehensive control is adopted, the pneumatic noise is reduced, the unsteady flow in the cavity is improved, and the method has important significance.
For the cavity of an aircraft, there are mainly several problems to be solved: the first is high-intensity pneumatic noise, namely after the cavity is exposed to free incoming flow, an unstable shear layer with high-frequency oscillation can be formed, and feedback sound waves after the shear layer impacts the rear wall can form self-sustaining oscillation in the cavity, so that the high-intensity pneumatic noise is formed, and the sound pressure level reaches 160-180 dB; the second is structural coupling, that is, the frequency of noise may reach 50-60Hz, which is close to the natural frequency of the coupling of the body, and it will produce acoustic fatigue and even damage to the cavity structure and the electronic equipment in the cabin. Meanwhile, in the aspect of airplane structural design, in order to avoid damage to the cavity and the airplane body caused by high-strength noise, the damage is avoided only by improving the structural strength of the airplane body, the structural weight of the airplane body is inevitably increased, and the overall performance of the airplane is greatly damaged.
At present, the research on the cavity of the aircraft mainly focuses on the aspects of the flow field and the flow field control in the cabin, and the main passive controller/exciter is additionally arranged on the front edge of the cavity, so that the increase of the equipment, the weight and the complexity of the aircraft is brought.
Therefore, the noise reduction device and method for the aircraft cavity based on the sound absorption material are urgently needed to be invented, the cavity is controlled from two aspects of flow and noise, additional equipment such as an air source and a control system is not introduced, better noise consistency is further realized, and the problems of severe noise and self-sustaining pressure oscillation in the aircraft cavity are solved.
Disclosure of Invention
In order to solve the technical problems of severe noise and self-sustaining pressure oscillation in a cavity when an aircraft flies in the prior art, the invention provides a noise reduction device and a noise reduction method for the cavity of the aircraft based on a sound absorption material, and the defects in the prior art are overcome.
An aircraft cavity noise reduction method based on sound absorption materials comprises the following steps:
s1, calculating a cavity self-sustaining oscillation frequency according to flight condition parameters of an aircraft;
s2, selecting a sound absorption material according to the self-sustaining oscillation frequency of the cavity and the sound absorption coefficient of different sound absorption materials under the frequency;
s3, fixing the sound absorption material on the cavity of the aircraft as the outer surface of the inner cavity of the cavity, keeping the length, depth and width of the aircraft unchanged, and completing cavity noise reduction.
Preferably, the specific method for calculating the cavity self-sustained oscillation frequency in step S1 is: obtaining the free flow speed U of the front edge of the cavity according to the flight condition parameters of the aircraft∞The length L of the cavity and the incoming flow Mach number M, and the 1-3 order cavity self-sustained oscillation frequency is calculated by the following formula:
where γ is the specific heat ratio, n is the number of modes, and κ is the empirical constant.
Preferably, the sound absorbing material of step S2 includes a porous sound absorbing material and a resonance sound absorbing structure.
Preferably, the porous sound absorption material of step S2 is fibrous or granular or foam; the resonance sound absorption structure is a micro-perforated plate resonance sound absorption structure.
Preferably, in step S2, the specific method for obtaining the sound absorption coefficient is actually measured by a standing wave tube test.
Preferably, in step S2, the specific method for obtaining the coefficient of the porous sound absorbing material is calculated by the following formula:
wherein EαFor absorbed energy, EiFor incident energy, R is the reflection coefficient, which is the ratio of the reflected sound pressure at the interface to the incident sound pressure.
Preferably, in step S2, the specific method for obtaining the sound absorption coefficient of the resonant sound absorption structure is calculated by the following formula:
where c is the speed of sound, ShIs the area of the hole, V is the volume of the cavity, lhThe depth of the hole.
Preferably, the specific method for fixing the sound-absorbing material on the aircraft cavity as the outer surface of the cavity inner cavity in step S3 is to fix the sound-absorbing material on the aircraft cavity by means of gluing, embedding or welding.
The noise reduction device for the aircraft cavity based on the sound absorption material is characterized by comprising a perforated plate, the sound absorption material and a rigid wall surface, wherein the perforated plate and the rigid wall surface are arranged in parallel; the perforated plate and the rigid wall surface form a cavity, and the sound absorption material is filled in the cavity in a specific filling mode that the cavity is filled with the sound absorption material; or the sound absorption material is filled on the side of the cavity close to the rigid wall surface, and a certain distance is reserved between the sound absorption material and the perforated plate; or the sound absorption material is filled in the side of the cavity close to the perforated plate, and a certain distance is reserved between the sound absorption material and the rigid wall surface.
An aircraft cavity noise reduction device based on sound absorption materials comprises a micro-perforated plate, wherein the micro-perforated plate is arranged in parallel with a rigid wall surface; the micro-perforated plate and the rigid wall surface form a cavity body, and the number of the micro-perforated plates is 1 or more.
The invention has the following beneficial effects: the noise reduction device comprises a cavity self-sustaining oscillation frequency obtained by calculation according to flight working condition parameters of an aircraft, an optimal sound absorption material selected according to the cavity self-sustaining oscillation frequency and sound absorption coefficients of different sound absorption materials under the frequency, and a sound absorption material serving as the outer surface of a cavity inner cavity and fixed on the aircraft cavity. The problems of severe noise and self-sustaining pressure oscillation in the cavity during flying of the aircraft can be effectively solved.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:
fig. 1 is a schematic flow chart of a cavity noise reduction method according to an embodiment of the present invention;
fig. 2 is a schematic structural view of a sound absorber according to embodiment 2 of the present invention;
FIG. 3 is a schematic structural view of a side of a sound absorbing material close to a perforated plate according to embodiment 3 of the present invention;
FIG. 4 is a schematic view of the structure of the sound-absorbing material of example 4 of the present invention near a rigid wall;
FIG. 5 is a schematic diagram of a micro-perforated plate structure according to embodiment 5 of the present invention;
FIG. 6 is a schematic diagram of a structure of a multi-layer micro-perforated plate according to example 6 of the present invention.
In the figure, 1, a perforated plate; 2. a rigid wall surface; 3. a sound absorbing material; 4. a cavity; 7. a micro-perforated plate; 8. a cavity body.
Detailed Description
In order to make the technical solutions and advantages of the embodiments of the present application more apparent, the following further detailed description of the exemplary embodiments of the present application with reference to the accompanying drawings makes it clear that the described embodiments are only a part of the embodiments of the present application, and are not exhaustive of all embodiments. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.
s1, calculating a cavity self-sustaining oscillation frequency according to flight condition parameters of an aircraft;
and calculating to obtain the self-sustaining oscillation frequency of the cavity according to flight working condition parameters of the aircraft, and according to the Rosster feedback loop theory, the vortex periodically falling off from the front edge of the cavity convects to the downstream in the shear layer. The vortices impinge on the cavity trailing edge, causing a series of acoustic pulsations that propagate upstream within the cavity. The internal component impinges on the cavity front wall causing more vortex shedding, forming a self-sustaining oscillating flow field. When the aircraft flies, according to parameters such as the free flow speed of the front edge of the cavity, the length of the cavity, the Mach number of incoming flow and the like, the self-sustained oscillation frequency of the cavity in the state can be calculated according to a Heller correction formula, and the self-sustained oscillation frequency is the main noise frequency.
Specifically, the specific method for calculating the cavity self-sustained oscillation frequency is as follows: obtaining the free flow speed U of the front edge of the cavity according to the flight condition parameters of the aircraft∞The length L of the cavity and the incoming flow Mach number M, and the 1-3 order cavity self-sustained oscillation frequency is calculated by the following formula:
where γ is the specific heat ratio, n is the number of modes (n ═ 1,2,3) and α, and κ is the empirical constant (α ═ 0.25, κ ═ 0.57).
Specifically, the specific method for calculating the cavity self-sustained oscillation frequency is as follows: obtained by CFD calculation.
Specifically, the specific method for calculating the cavity self-sustained oscillation frequency is as follows: the scale model is obtained by wind tunnel test measurement.
Specifically, the specific method for calculating the cavity self-sustained oscillation frequency is as follows: measured by flight experiments.
S2, selecting a sound absorption material according to the self-sustaining oscillation frequency of the cavity and the sound absorption coefficient of different sound absorption materials under the frequency;
the best sound absorption material is selected according to the cavity self-sustaining oscillation frequency and the sound absorption coefficients of different sound absorption materials under the frequency, and the sound absorption mechanism of the sound absorption material is mainly as follows: firstly, the action of viscosity and internal friction, and because the vibration speed of mass points is different at each position when the sound wave is transmitted, a speed gradient exists, so that the viscosity force or the internal friction force of interaction is generated between adjacent mass points, the movement of the mass points is hindered, and the sound energy is continuously converted into heat energy. Secondly, the heat conduction effect is that the density of medium particles is different everywhere when the sound wave is transmitted, so the temperature of the medium is different everywhere, and a temperature gradient exists, thereby heat transfer is generated between adjacent particles, and the sound energy is continuously converted into heat energy.
Specifically, the sound absorbing material includes a porous sound absorbing material and a resonance sound absorbing structure.
In particular, the porous sound absorbing material is fibrous or granular or foamed.
Specifically, the resonance sound absorbing structure is a micro-perforated plate resonance sound absorbing structure.
Specifically, the sound absorption coefficient of different sound absorption materials under the frequency can be obtained through actual measurement of standing wave tube tests according to the self-sustained oscillation frequency of the cavity.
Specifically, according to the cavity self-sustaining oscillation frequency and the sound absorption coefficients of different sound absorption materials under the frequency, the coefficient of the porous sound absorption material can be obtained by the following formula:
wherein EαFor absorbed energy, EiFor incident energy, R is the reflection coefficient, which is the ratio of the reflected sound pressure at the interface to the incident sound pressure.
Specifically, according to the cavity self-sustained oscillation frequency and the sound absorption coefficients of different sound absorption materials under the frequency, the sound absorption coefficient of the resonance sound absorption structure can be obtained by the following formula:
where c is the speed of sound, ShIs a holeArea, V is the volume of the cavity, lhThe depth of the hole.
When the acoustic wave wavelength is much larger than the pipe diameter (or small hole diameter), the end correction needs to be considered. The approximate expression of the end correction is
Wherein: phi is the ratio of the cross-sectional areas of the tubule and the cavity, ahFor the radius of the tubules, this equation is valid for φ < 0.2.
After considering the end correction, the calculation formula of the resonance frequency is as follows:
wherein: d is the thickness of the cavity l'hIs the effective length of the pipe.
The variation range of the sound absorption coefficient is 0-1, and the larger the sound absorption coefficient is, the better the sound absorption effect of the material is. Therefore, the best sound absorption material is selected according to the self-sustaining oscillation frequency of the cavity, the parameters such as the type, the material and the thickness of the sound absorption material, whether the cavity is added or not, the thickness of the cavity and the like are determined, and the sound absorption material for cavity noise reduction is determined.
S3, fixing the sound absorption material on the cavity of the aircraft as the outer surface of the inner cavity of the cavity, keeping the length, depth and width of the aircraft unchanged, and completing cavity noise reduction.
The sound absorption material is used as the outer surface of the cavity inner cavity, the sound absorption material is fixed with the aircraft cavity, and the length, depth and width of the aircraft cavity are kept unchanged, so that the noise reduction of the aircraft cavity is completed.
Specifically, the sound absorption material and the aircraft cavity can be fixed in a sticking mode;
specifically, the sound-absorbing material and the aircraft cavity can be fixed in an embedded manner;
specifically, the sound-absorbing material and the aircraft cavity can be fixed in a welding mode;
In this embodiment, the perforated plate 1 can play a role in protecting and fixing the sound-absorbing material 3 and transmitting sound; the perforated plate 1 and the rigid wall surface 2 form a chamber 4, and the sound-absorbing material 3 is filled in the chamber 4, so that the structure has good high-frequency sound-absorbing performance.
in this embodiment, the perforated plate 1 can play a role in protecting and fixing the sound-absorbing material 3 and transmitting sound; the perforated plate 1 and the rigid wall surface 2 form a chamber 4, and the sound-absorbing material 3 is filled in the chamber 4 close to the rigid wall surface 2, so that the structure has good high-frequency sound-absorbing performance. Compared with the embodiment 2, the low-frequency sound absorption effect of the device is improved after the chamber 4 is added to the perforated plate 1 and the sound absorption material 3 with the same size.
In this embodiment, the perforated plate 1 can play a role in protecting and fixing the sound-absorbing material 3 and transmitting sound; the perforated plate 1 and the rigid wall surface 2 form a chamber 4, and the sound-absorbing material 3 is filled in the chamber 4 close to the perforated plate 1, so that the structure has good high-frequency sound-absorbing performance. Compared with the embodiment 2, the low-frequency sound absorption effect of the device is improved after the chamber 4 is added to the perforated plate 1 and the sound absorption material 3 with the same size.
Embodiment 5, refer to fig. 5 to illustrate this embodiment, an aircraft cavity noise reduction device based on sound absorption material of this embodiment, a microperforated panel 7 and a rigid wall 2, the microperforated panel 7 is arranged in parallel with the rigid wall 2; the microperforated panel 7 forms a cavity 8 with the rigid wall 2.
In this embodiment, the micro-perforated plate 7 may have a noise reduction function; the micro-perforated plate 7 and the air layer behind the plate form a resonance sound absorption structure, and the structure has the characteristics of high sound absorption coefficient and wide sound absorption frequency band.
Embodiment 6, referring to fig. 6, this embodiment is described, and an aircraft cavity noise reduction device based on sound absorption material of this embodiment includes a plurality of microperforated panels 7 and a rigid wall surface 2, and the microperforated panels 7 are arranged in parallel with the rigid wall surface 2; the plurality of microperforated panels 7 form a plurality of hollow cavities with the rigid wall 2.
In this embodiment, the micro-perforated plate 7 may have a noise reduction function; the micro-perforated plate 7 and the air layer behind the plate form a resonance sound absorption structure, and the structure has the characteristics of high sound absorption coefficient and wide sound absorption frequency band.
The sound-absorbing material according to any of the above embodiments may be classified into a porous sound-absorbing material and a resonance sound-absorbing structure.
Specifically, the sound absorbing material may be classified into a fibrous shape, a granular shape, a foamed shape, and the like.
Specifically, the sound absorbing structure may be divided into a single resonator, a perforated plate resonance sound absorbing structure, a thin film resonance sound absorbing structure, a thin plate resonance sound absorbing structure, and the like.
The sound absorbing material of any of the above embodiments is affixed to the exterior surface of the cavity of the aircraft.
Specifically, the sound absorption material and the aircraft cavity can be fixed in a sticking mode;
specifically, the sound-absorbing material and the aircraft cavity can be fixed in an embedded manner;
specifically, the sound-absorbing material and the aircraft cavity can be fixed in a welding mode;
the working principle of the invention is as follows: when the aircraft flies, the self-sustained oscillation frequency of the cavity in the state is calculated according to parameters such as the free flow speed of the front edge of the cavity, the length of the cavity, the Mach number of incoming flow and the like and a Heller correction formula; secondly, selecting a sound absorption material according to the self-sustaining oscillation frequency of the cavity and the sound absorption coefficients of different sound absorption materials under the frequency; and finally, fixing the sound absorption material on the cavity of the aircraft as the outer surface of the inner cavity of the cavity, keeping the length, depth and width of the aircraft unchanged, and completing the noise reduction of the cavity.
It should be noted that, in the above embodiments, as long as the technical solutions can be aligned and combined without contradiction, those skilled in the art can exhaust all possibilities according to the mathematical knowledge of the alignment and combination, and therefore, the present invention does not describe the technical solutions after alignment and combination one by one, but it should be understood that the technical solutions after alignment and combination have been disclosed by the present invention.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art.
Claims (10)
1. An aircraft cavity noise reduction method based on sound absorption materials is characterized by comprising the following steps:
s1, calculating a cavity self-sustaining oscillation frequency according to flight condition parameters of an aircraft;
s2, selecting a sound absorption material according to the self-sustaining oscillation frequency of the cavity and the sound absorption coefficient of different sound absorption materials under the frequency;
s3, fixing the sound absorption material on the cavity of the aircraft as the outer surface of the inner cavity of the cavity, keeping the length, depth and width of the aircraft unchanged, and completing cavity noise reduction.
2. The method according to claim 1, wherein the specific method for calculating the cavity self-sustained oscillation frequency in step S1 is as follows: obtaining the free flow speed U of the front edge of the cavity according to the flight condition parameters of the aircraft∞The length L of the cavity and the incoming flow Mach number M, and the 1-3 order cavity self-sustained oscillation frequency is calculated by the following formula:
wherein gamma is specific heat ratio, n is mode number, and kappa is empirical constant;
or, the specific method for calculating the cavity self-sustained oscillation frequency is as follows: the calculation is carried out through CFD;
or, the specific method for calculating the cavity self-sustained oscillation frequency is as follows: measured by a scaled model wind tunnel test;
or, the specific method for calculating the cavity self-sustained oscillation frequency is as follows: measured by flight experiments.
3. The method as claimed in claim 2, wherein the sound absorbing material of step S2 is a porous sound absorbing material or a resonant sound absorbing structure.
4. The method as claimed in claim 3, wherein the porous sound absorbing material of step S2 is fibrous or granular or foam; the resonance sound absorption structure is a micro-perforated plate resonance sound absorption structure.
5. The method of claim 4, wherein the step S2 of obtaining the sound absorption coefficient is actually measured by a standing wave tube test.
6. The method as claimed in claim 3, wherein the specific method for obtaining the coefficient of the porous sound absorbing material in step S2 is calculated by the following formula:
wherein EαFor absorbed energy, EiFor incident energy, R is the reflection coefficient, which is the ratio of the reflected sound pressure at the interface to the incident sound pressure.
7. The method as claimed in claim 3, wherein the step S2 is carried out by calculating the sound absorption coefficient of the resonant sound absorption structure according to the following formula:
where c is the speed of sound, ShIs the area of the hole, V is the volume of the cavity, lhThe depth of the hole.
8. The method of claim 6 or 7, wherein step S3 is performed by fixing the sound-absorbing material on the aircraft cavity as the outer surface of the cavity inner cavity by means of gluing, embedding or welding.
9. The noise reduction device for the aircraft cavity based on the sound absorption material is characterized by comprising a perforated plate (1), the sound absorption material (3) and a rigid wall surface (2), wherein the perforated plate (1) and the rigid wall surface (2) are arranged in parallel; the perforated plate (1) and the rigid wall surface (2) form a cavity (4), the sound absorption material (3) is filled in the cavity (4), and the concrete filling mode is that the cavity (4) is filled with the sound absorption material (3); or the sound absorption material (3) is filled in the side of the cavity (4) close to the rigid wall surface (2), and a certain distance is reserved between the sound absorption material (3) and the perforated plate (1); or the sound absorption material is filled in the side of the cavity (4) close to the perforated plate (1), and a certain distance is reserved between the sound absorption material (3) and the rigid wall surface (2).
10. An aircraft cavity noise reduction device based on sound absorption materials is characterized by comprising a micro-perforated plate (7), wherein the micro-perforated plate (7) is arranged in parallel with a rigid wall surface (2); microperforated panel (7) and rigid wall (2) form cavity body (8), the quantity of microperforated panel (1) is 1 and above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110515994.0A CN113270084A (en) | 2021-05-12 | 2021-05-12 | Noise reduction device and method for aircraft cavity based on sound absorption material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110515994.0A CN113270084A (en) | 2021-05-12 | 2021-05-12 | Noise reduction device and method for aircraft cavity based on sound absorption material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113270084A true CN113270084A (en) | 2021-08-17 |
Family
ID=77230543
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110515994.0A Pending CN113270084A (en) | 2021-05-12 | 2021-05-12 | Noise reduction device and method for aircraft cavity based on sound absorption material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113270084A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10128207A1 (en) * | 2001-06-11 | 2002-12-12 | Alveo Ag Luzern | Acoustic insulation to absorb atmospheric noise, has an air impermeable film welded to an air permeable film without adhesive, and structured to form chambers by heat and deep drawing |
| CN101264798A (en) * | 2008-05-08 | 2008-09-17 | 上海交通大学 | Three-dimensional cavity resonance pulsating pressure and aerodynamic noise inhibition device |
| CN204898916U (en) * | 2015-08-24 | 2015-12-23 | 青岛声达技术有限公司 | Multilayer double entry cavity wide band sound absorption device |
| CN205158899U (en) * | 2015-10-29 | 2016-04-13 | 潘路希 | Combination perforated plate |
| CN107741313A (en) * | 2017-11-29 | 2018-02-27 | 中国航空工业集团公司沈阳空气动力研究所 | A kind of low wide Mach number wind-tunnel laminar flow double venturi of disturbance |
| CN111564149A (en) * | 2020-04-30 | 2020-08-21 | 中国飞机强度研究所 | Cavity structure noise control method and device based on controllable impedance boundary |
| CN111581733A (en) * | 2020-05-22 | 2020-08-25 | 中国航空工业集团公司西安飞机设计研究所 | Design method of sound absorption structure of micropunch plate of nacelle of turbofan engine |
-
2021
- 2021-05-12 CN CN202110515994.0A patent/CN113270084A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10128207A1 (en) * | 2001-06-11 | 2002-12-12 | Alveo Ag Luzern | Acoustic insulation to absorb atmospheric noise, has an air impermeable film welded to an air permeable film without adhesive, and structured to form chambers by heat and deep drawing |
| CN101264798A (en) * | 2008-05-08 | 2008-09-17 | 上海交通大学 | Three-dimensional cavity resonance pulsating pressure and aerodynamic noise inhibition device |
| CN204898916U (en) * | 2015-08-24 | 2015-12-23 | 青岛声达技术有限公司 | Multilayer double entry cavity wide band sound absorption device |
| CN205158899U (en) * | 2015-10-29 | 2016-04-13 | 潘路希 | Combination perforated plate |
| CN107741313A (en) * | 2017-11-29 | 2018-02-27 | 中国航空工业集团公司沈阳空气动力研究所 | A kind of low wide Mach number wind-tunnel laminar flow double venturi of disturbance |
| CN111564149A (en) * | 2020-04-30 | 2020-08-21 | 中国飞机强度研究所 | Cavity structure noise control method and device based on controllable impedance boundary |
| CN111581733A (en) * | 2020-05-22 | 2020-08-25 | 中国航空工业集团公司西安飞机设计研究所 | Design method of sound absorption structure of micropunch plate of nacelle of turbofan engine |
Non-Patent Citations (1)
| Title |
|---|
| 王显圣等: "弹性空腔流致噪声/结构振动特性试验", 《航空学报》 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Jing et al. | Experimental investigations of perforated liners with bias flow | |
| Tam et al. | On the tones and pressure oscillations induced by flow over rectangular cavities | |
| CN111929026B (en) | Low-frequency pressure pulsation suppression method for wind tunnel 3/4 opening test section | |
| Fedorov et al. | Stability of hypersonic boundary layer on porous wall with regular microstructure | |
| DeMetz et al. | Laminar and turbulent shear flow induced cavity resonances | |
| Bravo et al. | Absorption and transmission of boundary layer noise through flexible multi-layer micro-perforated structures | |
| CN103533488A (en) | Helmholtz resonator and design method thereof | |
| Murray et al. | Development of a single degree of freedom perforate impedance model under grazing flow and high SPL | |
| Maury et al. | The use of microperforations to attenuate the cavity pressure fluctuations induced by a low-speed flow | |
| Zhu et al. | Multilayer structures for high-intensity sound energy absorption in low-frequency range | |
| Welsh et al. | Acoustics and experimental methods: the influence of sound on flow and heat transfer | |
| CN113270084A (en) | Noise reduction device and method for aircraft cavity based on sound absorption material | |
| Hou et al. | Case study: numerical study of the noise reduction characteristics of corrugated perforated pipe mufflers | |
| Kohlenberg et al. | Modelling of acoustic liners consisting of helmholtz resonators coupled with a second cavity by flexible walls | |
| Bauer et al. | Noise generated by boundary-layer interaction with perforated acoustic liners | |
| Lee et al. | Passive control techniques to alleviate supersonic cavity flow oscillation | |
| CN110705157B (en) | Rectifying cover similar structure extrapolation correction method based on scaling model | |
| Simon | Low frequency sound absorption of resonators with flexible tubes | |
| Murata et al. | Experimental Research on New Acoustic Liners Combined with Fine-Perforated-Film | |
| Simon et al. | Overview of low frequency resonators based on LEONAR design | |
| Simon et al. | Development and assessment of a LEONAR acoustic liner design for landing systems noise minimization | |
| CN112196672A (en) | Micro-miniature turbojet engine silencer and design method thereof | |
| Yan et al. | Experiment-simulation study on noise reduction of cylinder shell with horn Helmholtz resonator | |
| US20130306400A1 (en) | Method of Designing and Making an Acoustic Liner for Jet Aircraft Engines | |
| CN213478496U (en) | Micro-miniature turbojet engine silencer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210817 |