CN111564149A - Cavity structure noise control method and device based on controllable impedance boundary - Google Patents
Cavity structure noise control method and device based on controllable impedance boundary Download PDFInfo
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- CN111564149A CN111564149A CN202010364109.9A CN202010364109A CN111564149A CN 111564149 A CN111564149 A CN 111564149A CN 202010364109 A CN202010364109 A CN 202010364109A CN 111564149 A CN111564149 A CN 111564149A
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- 210000003454 tympanic membrane Anatomy 0.000 claims description 8
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- G—PHYSICS
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- G10K11/161—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general in systems with fluid flow
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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
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Abstract
The invention belongs to the field of noise control, and discloses a cavity structure noise control method based on a controllable impedance boundary.
Description
Technical Field
The invention belongs to the field of noise control, and particularly relates to a cavity structure noise control method and a cavity structure noise control device based on a controllable impedance boundary.
Background
When fluid flows through the cavity structure, due to interaction between the flow of the shear layer outside the cavity and the flow in the cavity, a strong self-excited vibration phenomenon will occur in the cavity, severe pressure, speed and other pulsations are generated, and strong noise is accompanied, and the phenomenon is radiated and spread outwards and towards the front end of the cavity, and is called cavity flow-induced oscillation. The problems related to unsteady flow, flow instability, sound-flow interaction and the like are one of the hot problems in research in fluid mechanics, and the problems are often encountered in engineering practice, such as an embedded missile bay of an aircraft, a landing gear bay, a gap of a high-speed rail car, a sunroof of an automobile and the like. In order to effectively change the flow state in the cavity and restrain strong cavity noise, a series of researches are carried out by a plurality of research institutions at home and abroad aiming at the cavity flow and the cavity noise.
The methods for controlling the flow and noise of the cavity structure mainly include active control methods (such as leading edge plasma excitation, leading edge high frequency forcing, leading edge mass injection, etc.) and passive control methods (such as leading edge spoilers, vortex generators, trailing edge ramps, etc.). The existing active control method often forms flow disturbance at the front edge position of the cavity to influence the incoming flow condition, and the adopted methods all need to add a mechanical actuating mechanism and increase an external excitation voltage and an air entraining system, so that the structure near the cavity structure is more complex, and the weight of the cavity structure is increased; in the passive control method, as the turbulence structure is added at the front edge of the cavity, the aerodynamic performance of the cavity structure area can be influenced, and the noise is reduced by aerodynamic loss, so that the actual engineering application is difficult to obtain.
Disclosure of Invention
The purpose of the invention is as follows: the cavity structure noise control method and the cavity structure noise control device based on the controllable impedance boundary are simple in structure and good in noise reduction effect, and propagation of noise in a cavity and generation and continuation of sound-vortex coupling of the cavity structure in an airflow environment are restrained, so that the noise in the cavity structure is reduced.
The technical scheme of the invention is as follows: in one aspect, a method for controlling noise of a cavity structure based on a controllable impedance boundary is provided, the cavity structure comprises a front edge, a cavity with an opening at one end and a rear edge, airflow flows from the front edge to the rear edge of the cavity structure,
the control method comprises the following steps: replacing a bottom plate of the cavity with a micro-perforated plate, and arranging rigid wall plates on one side of the micro-perforated plate, which is far away from the airflow, at intervals; the micro-perforated plate and the rigid wall plate are both connected with the side wall of the cavity, and a gap exists between the micro-perforated plate and the rigid wall plate.
Furthermore, the rigid wall plate is movably connected with the side wall of the cavity, and the distance between the rigid wall plate and the micro-perforated plate is adjustable.
Further, a sound absorbing material is disposed between the microperforated panel and the rigid wall panel.
Furthermore, a sensor is arranged on one side of the micro-perforated plate close to the airflow, and a plurality of loudspeakers are arranged on one side of the rigid wall plate far away from the micro-perforated plate;
and adjusting the excitation voltage of the loudspeaker according to the acoustic parameter information fed back by the sensor so as to enable the tympanic membrane at the top end of the loudspeaker to vibrate to different degrees and change the thickness of an air layer between the tympanic membrane and the micro-perforated plate.
Further, a sound absorbing material is disposed between the microperforated panel and the rigid wall panel.
In another aspect, a method for controlling noise of a cavity structure based on a controllable impedance boundary is provided, the cavity structure comprises a front edge, a cavity with an opening at one end and a rear edge, airflow flows from the front edge to the rear edge of the cavity structure,
the control method comprises the following steps: replacing a bottom plate of the cavity with a micro-perforated plate, and arranging electrically driven soft shells on one side of the micro-perforated plate, which is far away from the airflow, at intervals; the micro-perforated plate and the electrically-driven soft shell are both connected with the side wall of the cavity, and a gap is formed between the micro-perforated plate and the electrically-driven soft shell; and adjusting the driving voltage of the electrically-driven soft shell to drive the electrically-driven soft shell to move relative to the micro-perforated plate.
Further, a sensor is arranged on the inner wall of the cavity above the micro-perforated plate; and adjusting the driving voltage of the electrically-driven soft shell according to the acoustic parameter information fed back by the sensor to drive the electrically-driven soft shell to move relative to the micro-perforated plate.
Further, a sound absorbing material is disposed between the microperforated panel and the electrically-driven bladder.
On the other hand, the cavity structure noise control device based on the controllable impedance boundary is provided, the cavity structure comprises a front edge, a cavity with an opening at one end and a rear edge, airflow flows from the front edge to the rear edge of the cavity structure, a bottom plate of the cavity is a micro-perforated plate, and a rigid wall plate or an electrically driven soft shell is arranged on one side of the micro-perforated plate away from the airflow at intervals; the rigid wall plate or the electrically driven soft shell is connected with the side wall of the cavity; a gap exists between the microperforated panel and the rigid wall plate or the electrically driven bladder.
The invention has the technical effects that:
according to the invention, the movable rigid wall plate or the electrically-driven soft shell is added behind the micro-perforated plate, and the transmission of noise in the cavity is absorbed and inhibited by adjusting the position of the rigid wall plate behind the micro-perforated plate and the position of the electrically-driven soft shell, so that the purpose of reducing the noise is achieved.
In the invention, the sound absorption material is arranged between the micro-perforated plate and the rigid wall plate or the electrically driven soft shell, so that the sound absorption material absorbs noise; if no sound absorbing material is placed between the microperforated panel and the rigid wall panel or the electrically driven bladder, acoustic energy is dissipated by air vibration.
Under the prior art conditions and the test conditions, the method with the simple structure can play a good role in suppressing the cavity noise, and particularly has a good effect of suppressing the amplitude of the sound pressure level at the main peak frequency of the cavity structure. The method has the advantages of relatively simple structure, good reliability, good applicability, easy popularization and application, and great practical engineering application and military value.
Drawings
FIG. 1 is a schematic view of a cavity structure;
fig. 2 is a schematic view of the noise reduction principle of embodiment 1;
fig. 3 is a schematic view of the noise reduction principle of embodiment 2;
fig. 4 is a schematic view of the noise reduction principle of embodiment 3.
Detailed Description
When air flows through the cavity structure, due to interaction between flow of the shear layer outside the cavity and flow in the cavity, a strong self-oscillation phenomenon can occur in the cavity, severe pressure and velocity pulsation is generated, airflow impacts the rear wall of the cavity and generates strong noise, one part of the generated noise can be transmitted to the outside of the cavity, the other part of the generated noise can be transmitted to the front edge area of the cavity from the rear edge area of the cavity, and the noise transmitted to the front edge of the cavity can influence the flow of the shear layer at the front edge of the cavity and the formation of vortexes after reaching the front edge of the cavity, so that the noise of the cavity is more serious.
The technical idea of the invention is as follows: the invention provides a cavity structure noise control method based on a controllable impedance boundary, which replaces a cavity structure bottom plate with a micro-perforated plate, adds a movable rigid wall plate or an electrically driven soft shell behind the micro-perforated plate, changes the acoustic impedance of the cavity structure boundary wall surface by adjusting the position of the rigid wall plate behind the micro-perforated plate and the position of the electrically driven soft shell, attenuates the process of generating noise forward propagation at the rear edge of a cavity structure, reduces the noise amplitude reaching the unstable shearing layer at the front edge of the cavity, inhibits the unstable shearing layer from generating new shedding vortexes, and weakens the generation and continuation of the sound-vortex coupling in the cavity structure, thereby achieving the purpose of reducing the noise.
The acoustic impedance of the surface of the cavity bottom plate structure can be changed by reasonably designing the distance between the micro-perforated plate and the rigid wall plate, so that the acoustic impedance of the micro-perforated plate is matched with the optimal impedance, the method of adding the rigid wall plate behind the micro-perforated plate mainly aims at single frequency, and the distance between the micro-perforated plate and the rigid wall plate is increased sharply along with the reduction of noise frequency. The method for adding the rigid wallboard after the micro-perforation mainly aims at the second-order peak frequency with the maximum cavity sound pressure level amplitude, the range of the second-order peak frequency can be calculated through a theoretical formula according to the geometric dimension of the cavity and the incoming flow speed, and the sound pressure level amplitude at the second-order peak frequency of the cavity can be reasonably reduced by reasonably designing the geometric parameters of the micro-perforated plate and the distance between the micro-perforated plate and the rigid wallboard.
The micro-perforated plate and electrically-driven soft shell double-layer structure mainly realizes noise control in a wider frequency range through continuous optimization of a control algorithm and a control target, obtains acoustic impedance and particle vibration speed of the surface of the micro-perforated plate by adopting a reasonable error sensor, and then adjusts the movement of the electrically-driven soft shell to obtain a better noise control effect.
Example 1
In this embodiment, a method for controlling noise of a cavity structure based on a controllable impedance boundary is provided, as shown in fig. 2, and fig. 2 is a schematic diagram of a noise reduction principle of embodiment 1. Fig. 1 is a schematic view of a cavity structure, and as shown in fig. 1 and 2, the cavity structure 1 includes a front edge 10 and a rear edge 20, and a front wall 31 and a rear wall 32, and an air flow flows from the front edge to the rear edge. The noise control method of the embodiment comprises the following steps:
replacing the bottom plate of the cavity with a micro-perforated plate 30, and arranging rigid wall plates 40 at intervals on one side of the micro-perforated plate 30, which is far away from the airflow; both microperforated panel 30 and rigid wall panel 40 are connected to the side walls of the chamber. The side walls of the cavity comprise a front wall 31 and a rear wall 32.
In this embodiment, it is not limited that the microperforated panel and the rigid wall panel are both fixedly connected to the side wall of the chamber, and the rigid wall panel may be movably connected to the side wall of the chamber, so that the distance between the rigid wall panel and the microperforated panel is adjustable.
As one of the preferred embodiments of this embodiment, there is a gap between microperforated panel 30 and rigid wall panel 40, and acoustic energy is dissipated by air vibration between microperforated panel 30 and rigid wall panel 40.
Further, as one of the other preferred embodiments of the present embodiment, the present embodiment provides a sound absorbing material 50 between the microperforated panel 30 and the rigid wall panel 40, by which noise is absorbed.
In the noise control method provided by the embodiment, the cavity bottom plate is replaced by the micro-perforated plate, and the micro-perforated plate, the rigid wall plate and the sound absorbing material form an impedance composite muffling structure. The structure has better sound absorption effect on certain frequency noise and medium-high frequency noise. The cavity noise has obvious peak noise and usually takes the second order as a main part, the second order peak frequency can be calculated through a theoretical formula according to the geometric dimension of the cavity and the incoming flow speed, and the sound pressure level amplitude at the second order peak frequency of the cavity can be reasonably reduced by reasonably designing the geometric parameters (including aperture, thickness and perforation rate) of the micro-perforated plate and the distance between the micro-perforated plate and the rigid wall plate, so that the purpose of reducing the cavity noise is achieved.
Example 2
In this embodiment, another cavity structure noise control method based on a controllable impedance boundary is provided, as shown in fig. 3, fig. 3 is a schematic diagram of a noise reduction principle of embodiment 2. As shown in connection with fig. 3, the cavity structure 1 comprises a front edge 10 and a rear edge 20, from which the air flow flows towards the rear edge, a front wall 31 and a rear wall 32. The noise control method of the embodiment comprises the following steps:
firstly, replacing a bottom plate of the cavity with a micro-perforated plate 30, and arranging rigid wall plates 40 at intervals on one side of the micro-perforated plate 30, which is far away from the airflow; both microperforated panel 30 and rigid wall panel 40 are connected to the side walls of the chamber. The side walls include a front wall 31 and a rear wall 32.
Then, a sensor 60 is provided in the inner wall of the cavity above the microperforated panel, and a plurality of speakers 70 are arranged on the side of the rigid wall plate 40 remote from the microperforated panel 30. And adjusting the excitation voltage of the loudspeaker according to the acoustic parameter information fed back by the sensor so as to enable the tympanic membrane 71 at the top end of the loudspeaker to vibrate to different degrees and change the thickness of the air layer between the tympanic membrane and the micro-perforated plate.
Further, in this embodiment, a small amount of sound absorbing material may also be provided between the microperforated panel and the rigid wall panel.
In the control method of the embodiment, the eardrum at the top end of the loudspeaker can vibrate in different degrees under different excitation voltages, the vibration changes the thickness of an air layer between the eardrum of the loudspeaker and the micro-perforated plate, and the impedance of the control structure is adjusted by matching with a control algorithm; the voltage is controlled according to the frequency and amplitude conditions of the main components of the cavity noise, and the noise control of a wide frequency band can be realized.
Example 3
In this embodiment, another cavity structure noise control method based on a controllable impedance boundary is provided, as shown in fig. 4, fig. 4 is a schematic diagram of a noise reduction principle of embodiment 3. As shown in connection with fig. 4 and 1, the cavity structure 1 comprises a front edge 10 and a rear edge 20, a front wall 31 and a rear wall 32. The noise control method of the embodiment comprises the following steps:
replacing the bottom plate of the cavity with a micro-perforated plate 30, and arranging electrically driven soft shells 80 at intervals on one side of the micro-perforated plate 30, which is far away from the airflow; both microperforated panel 30 and rigid wall panel 40 are connected to the side walls of the chamber. The side walls include a front wall 31 and a rear wall 32. By adjusting the drive voltage of the electrically driven soft shell, the electrically driven soft shell 80 is driven to move relative to the microperforated panel to adjust the distance between the electrically driven soft shell and the microperforated panel. The electrically-driven soft shell of the embodiment is made of piezoelectric materials or other materials capable of generating obvious displacement under voltage excitation, and the position of the electrically-driven soft shell is moved by adjusting the intensity of external excitation voltage.
Further, a sensor 60 can be arranged on the inner wall of the cavity above the micro-perforated plate, and the driving voltage of the electrically-driven soft shell is adjusted according to the acoustic parameter information fed back by the sensor, so as to drive the electrically-driven soft shell 80 to move relative to the micro-perforated plate 30.
Further, sound absorbing material may also be disposed between microperforated panel 30 and electrically driven bladder 80.
This embodiment, microperforated panel and the combination of the soft shell of electricity that drives in the control method that provides, it is portable unit to drive the soft shell to drive the electricity, along with driving voltage is different, it can move in microperforated panel below to drive the soft shell to drive the electricity, this makes the microperforated panel and drives the distance between the soft shell to become adjustable with the electricity, the regional feedback sensor of cooperation cavity back wall, through control algorithm and feedback parameter (including cavity noise primary frequency noise component) adjust the soft shell position of electricity that drives, make the wall impedance of cavity structure and air impedance well match, realize the noise control of broad frequency section.
The cavity test device is designed according to the method provided by the invention, and after the test device is used in a test wind tunnel, the propagation of noise generated by the cavity structure can be well inhibited by using the method, and the sound-vortex interference in the cavity structure is effectively inhibited. According to the geometric dimension of the cavity structure and the incoming flow speed, the geometric parameters of the micro-perforated plate, the thickness of the air layer, the vibration amplitude of the loudspeaker and the like are reasonably designed, so that a better noise reduction effect can be obtained, and the method has a higher engineering practical application value and a higher military value.
Claims (9)
1. A cavity structure noise control method based on controllable impedance boundary, the cavity structure comprises a front edge, a cavity with an opening at one end and a rear edge, airflow flows from the front edge to the rear edge of the cavity structure,
the control method comprises the following steps: replacing a bottom plate of the cavity with a micro-perforated plate, and arranging rigid wall plates on one side of the micro-perforated plate, which is far away from the airflow, at intervals; the micro-perforated plate and the rigid wall plate are both connected with the side wall of the cavity, and a gap exists between the micro-perforated plate and the rigid wall plate.
2. The control method of claim 1, wherein the rigid wall plate is movably connected to the side wall of the chamber, and the distance between the rigid wall plate and the microperforated plate is adjustable.
3. The control method of claim 1, wherein a sound absorbing material is disposed between the microperforated panel and the rigid wall panel.
4. The control method according to any one of claim 1,
a sensor is arranged on one side of the micro-perforated plate close to the airflow, and a plurality of loudspeakers are arranged on one side of the rigid wall plate far away from the micro-perforated plate;
and adjusting the excitation voltage of the loudspeaker according to the acoustic parameter information fed back by the sensor so as to enable the tympanic membrane at the top end of the loudspeaker to vibrate to different degrees and change the thickness of an air layer between the tympanic membrane and the micro-perforated plate.
5. A control method according to claim 4, characterized in that a sound-absorbing material is arranged between the microperforated panel and the rigid wall panel.
6. A cavity structure noise control method based on controllable impedance boundary, the cavity structure comprises a front edge, a cavity with an opening at one end and a rear edge, airflow flows from the front edge to the rear edge of the cavity structure,
the control method comprises the following steps: replacing a bottom plate of the cavity with a micro-perforated plate, and arranging electrically driven soft shells on one side of the micro-perforated plate, which is far away from the airflow, at intervals; the micro-perforated plate and the electrically-driven soft shell are both connected with the side wall of the cavity, and a gap is formed between the micro-perforated plate and the electrically-driven soft shell; and adjusting the driving voltage of the electrically-driven soft shell to drive the electrically-driven soft shell to move relative to the micro-perforated plate.
7. The control method according to claim 6, wherein a sensor is provided on an inner wall of the cavity above the micro-perforated plate;
and adjusting the driving voltage of the electrically-driven soft shell according to the acoustic parameter information fed back by the sensor to drive the electrically-driven soft shell to move relative to the micro-perforated plate.
8. The control method of claim 6, wherein a sound absorbing material is disposed between the microperforated panel and the electrically-driven bladder.
9. A cavity structure noise control device based on a controllable impedance boundary comprises a front edge, a cavity with an opening at one end and a rear edge, and airflow flows from the front edge to the rear edge of the cavity structure; the rigid wall plate or the electrically driven soft shell is connected with the side wall of the cavity; a gap exists between the microperforated panel and the rigid wall plate or the electrically driven bladder.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112365872A (en) * | 2020-11-10 | 2021-02-12 | 国网北京市电力公司 | Noise reduction regulation and control method, device and system and processor |
| CN113270084A (en) * | 2021-05-12 | 2021-08-17 | 中国航空工业集团公司沈阳空气动力研究所 | Noise reduction device and method for aircraft cavity based on sound absorption material |
| CN115206277A (en) * | 2021-04-06 | 2022-10-18 | 湾流航空航天公司 | Active noise cancellation of equipment fan noise on an aircraft |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101828988A (en) * | 2010-05-20 | 2010-09-15 | 中南大学 | Active sound absorption adjustable and noiseproof earplug with composite structure |
| WO2010147272A1 (en) * | 2009-06-15 | 2010-12-23 | 한국과학기술원 | Semi-active sound absorption system and method thereof |
| CN102044239A (en) * | 2009-10-22 | 2011-05-04 | 北京绿创声学工程股份有限公司 | Micro-perforated plate with resonant sound absorption structure |
| GB201708245D0 (en) * | 2017-05-23 | 2017-07-05 | Kp Acoustics Ltd | Acoustic resonators |
| CN107542514A (en) * | 2017-09-08 | 2018-01-05 | 合肥工业大学 | A kind of adaptive bipolar microperforated panel silencer |
| CN107782523A (en) * | 2017-10-31 | 2018-03-09 | 中国空气动力研究与发展中心高速空气动力研究所 | A kind of new cavity modal noise standing wave decomposition method |
| CN108867986A (en) * | 2018-07-02 | 2018-11-23 | 长春理工大学 | Combined frequency-change acoustic tile |
-
2020
- 2020-04-30 CN CN202010364109.9A patent/CN111564149B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010147272A1 (en) * | 2009-06-15 | 2010-12-23 | 한국과학기술원 | Semi-active sound absorption system and method thereof |
| CN102044239A (en) * | 2009-10-22 | 2011-05-04 | 北京绿创声学工程股份有限公司 | Micro-perforated plate with resonant sound absorption structure |
| CN101828988A (en) * | 2010-05-20 | 2010-09-15 | 中南大学 | Active sound absorption adjustable and noiseproof earplug with composite structure |
| GB201708245D0 (en) * | 2017-05-23 | 2017-07-05 | Kp Acoustics Ltd | Acoustic resonators |
| CN107542514A (en) * | 2017-09-08 | 2018-01-05 | 合肥工业大学 | A kind of adaptive bipolar microperforated panel silencer |
| CN107782523A (en) * | 2017-10-31 | 2018-03-09 | 中国空气动力研究与发展中心高速空气动力研究所 | A kind of new cavity modal noise standing wave decomposition method |
| CN108867986A (en) * | 2018-07-02 | 2018-11-23 | 长春理工大学 | Combined frequency-change acoustic tile |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112365872A (en) * | 2020-11-10 | 2021-02-12 | 国网北京市电力公司 | Noise reduction regulation and control method, device and system and processor |
| CN112365872B (en) * | 2020-11-10 | 2024-05-28 | 国网北京市电力公司 | Noise reduction regulation method, device and system and processor |
| CN115206277A (en) * | 2021-04-06 | 2022-10-18 | 湾流航空航天公司 | Active noise cancellation of equipment fan noise on an aircraft |
| CN113270084A (en) * | 2021-05-12 | 2021-08-17 | 中国航空工业集团公司沈阳空气动力研究所 | Noise reduction device and method for aircraft cavity based on sound absorption material |
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| CN111564149B (en) | 2023-11-21 |
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