CN116045414A - Continuous frequency-adjustable ventilation sound insulation structure based on Fano resonance and frequency modulation method - Google Patents

Continuous frequency-adjustable ventilation sound insulation structure based on Fano resonance and frequency modulation method Download PDF

Info

Publication number
CN116045414A
CN116045414A CN202211620699.2A CN202211620699A CN116045414A CN 116045414 A CN116045414 A CN 116045414A CN 202211620699 A CN202211620699 A CN 202211620699A CN 116045414 A CN116045414 A CN 116045414A
Authority
CN
China
Prior art keywords
frequency
sound insulation
motor
ventilation
controller
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.)
Granted
Application number
CN202211620699.2A
Other languages
Chinese (zh)
Other versions
CN116045414B (en
Inventor
吴晓莉
王俪静
缑斌丽
郁毛林
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nanjing Forestry University
Original Assignee
Nanjing Forestry University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nanjing Forestry University filed Critical Nanjing Forestry University
Priority to CN202211620699.2A priority Critical patent/CN116045414B/en
Publication of CN116045414A publication Critical patent/CN116045414A/en
Application granted granted Critical
Publication of CN116045414B publication Critical patent/CN116045414B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F7/00—Ventilation
    • F24F7/007—Ventilation with forced flow
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/24—Means for preventing or suppressing noise
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
    • F24F13/24—Means for preventing or suppressing noise
    • F24F2013/245—Means for preventing or suppressing noise using resonance
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)

Abstract

The invention relates to a continuous frequency-adjustable ventilation sound insulation structure based on Fano resonance and a frequency modulation method. The structure comprises a ventilation sound insulation unit, a frequency modulation mechanism, a data acquisition and analysis system and a control driving system; the ventilation and sound insulation unit comprises a hollow pipe with spiral blades and a cube base with threaded through holes, the matched spiral blades are screwed into the threaded through holes of the cube base by the frequency modulation mechanism, and the greater the screwing depth is, the lower the frequency of the isolation sound wave is; the data acquisition and analysis system completes the determination of noise frequency, data are transmitted to the control driving system, the driving motor drives the frequency modulation mechanism to work, and the frequency modulation mechanism drives the spiral blade to screw in and screw out, so that the continuous adjustment of sound insulation frequency is realized. The invention has the advantages of simple frequency modulation, good ventilation and sound insulation effects, thin thickness and the like, and has great application potential in building acoustics.

Description

Continuous frequency-adjustable ventilation sound insulation structure based on Fano resonance and frequency modulation method
Technical Field
The invention relates to the technical field of noise treatment equipment, in particular to a ventilation and sound insulation structure capable of adjusting an internal structure in real time according to external environment noise so as to change sound insulation frequency, and particularly relates to a continuous adjustable frequency ventilation and sound insulation structure based on Fano resonance and a frequency modulation method.
Background
The sound insulation and ventilation are a pair of contradictions, the sound insulation requires that the material density is high, the structure is compact and seamless, the low-frequency sound insulation is required to be thick and heavy, the ventilation and heat dissipation can cause almost all leakage of noise, and the traditional material based on the mass density law can not realize sound insulation and ventilation at the same time. In recent years, acoustic metamaterials are widely focused on the academic circles by virtue of the unique acoustic properties, and a new thought is provided for the research and development of ventilation and sound insulation equipment.
The acoustic metamaterial is an artificially designed sub-wavelength size structure, can effectively regulate and control sound waves, and achieves the function which cannot be achieved by the traditional material. The ventilation and sound insulation by using the acoustic metamaterial generally has two principles, namely, a resonant cavity such as a Helmholtz resonator is arranged beside a ventilation pipeline, when the frequency of sound waves is matched with the resonant frequency of the Helmholtz resonator, the energy of the sound waves is consumed, the transmission sound energy of the structure is weakened, the purpose of sound insulation is achieved, but the sound insulation frequency range is narrow, and the ventilation area is limited. The other is to design a parallel coiled path acoustic wave channel beside the ventilation pipeline, discrete state waves are generated when the acoustic wave passes through the coiled path, the waveform of the acoustic wave channel is unchanged and is continuous, fano resonance is realized by coupling the two waveforms, the acoustic wave line type is an asymmetric Fano line type, the acoustic wave is reflected at the structural resonance frequency, and air can be transmitted through the two channels, so that efficient ventilation and sound insulation are realized, and the ventilation area can reach 60%.
However, once the ventilation and sound insulation structures are manufactured, the ventilation and sound insulation structures cannot be changed, so that the noise reduction frequency is fixed and cannot adapt to complex and changeable noise environments, if the noise reduction frequency is required to be changed, structural design and reassembly are required, and therefore the flexibility is low, and the practical application in various scenes cannot be met.
Disclosure of Invention
The invention aims to overcome the defects of the prior art, combines an acoustic metamaterial based on the Fano resonance principle with an active control technology to construct a self-adaptive ventilation and sound insulation structure with the functions of noise identification, active structure adjustment and real-time sound insulation frequency adjustment, and particularly relates to a continuous adjustable frequency ventilation and sound insulation structure based on Fano resonance and a frequency modulation method.
In order to achieve the technical purpose, the invention adopts the following technical scheme:
a continuously adjustable frequency ventilation and sound insulation structure based on Fano resonance comprises a ventilation and sound insulation wall, a frequency modulation mechanism, a data acquisition and analysis system and a control driving system;
the ventilation sound insulation wall is formed by connecting a plurality of ventilation sound insulation units, wherein each ventilation sound insulation unit comprises a cube base, a hollow tube and a spiral blade, the spiral blade is fixedly connected to the outer wall of the hollow tube, a through hole is formed in the middle of the cube base, threads matched with the spiral blade are distributed on the inner wall of the through hole, the spiral blade can be screwed in and screwed out of the through hole, a spiral channel is formed by the outer wall of the hollow tube, the spiral blade and the through hole wall on the cube base in a surrounding mode, and sound waves and air flow enter and exit from the hollow tube and the spiral channel;
the frequency modulation mechanism comprises a plurality of gears and a plurality of synchronous belts, each gear is fixedly connected to the outer side of the end part of the hollow tube, each synchronous belt is a toothed belt, and the belt teeth of each synchronous belt are meshed with two adjacent gears;
the data acquisition and analysis system comprises a microphone and a microprocessor, wherein the microphone is fixedly connected to the sound receiving surface of the ventilation sound insulation wall, and the microprocessor is fixedly connected to the motor gear base;
the control driving system comprises a motor gear base, a motor gear, a first synchronous belt and a controller, wherein the motor gear base is fixedly connected to a ventilation and sound insulation wall, the motor and the controller are fixedly connected to the motor gear base, an output shaft of the motor is connected with the motor gear, and the motor gear is connected with a gear on the hollow pipe through the first synchronous belt;
the microphone is connected with the microprocessor, the microprocessor is connected with the controller, and the controller is connected with the motor.
As a further improved technical scheme of the invention, the data acquisition and analysis system further comprises an angle sensor, an output shaft of the motor is connected with the motor gear through a coupler, the end part of the shaft in the center of the motor gear is fixedly connected with the angle sensor, the angle sensor is connected with the microprocessor, and the angle sensor is used for detecting the rotation angle data of the motor gear and sending the rotation angle data to the microprocessor.
As a further improved technical scheme of the invention, the microphone is used for collecting noise of the external environment; the microprocessor is used for receiving the noise collected by the microphone, analyzing and calculating, and sending the main frequency in the analyzed and calculated noise frequency to the controller; the controller is used for receiving data sent by the microprocessor, converting a main frequency value into an angle through which a motor gear rotates through a control equation and then driving the motor to rotate; the motor is used for driving the first synchronous belt to rotate so as to drive all synchronous belts in the frequency modulation mechanism to rotate together, and finally drives the helical blade to rotate, so that the helical blade is screwed into or out of the cube base, and the sound insulation frequency is adjusted.
As a further improved technical scheme of the invention, the through hole is cylindrical.
As a further improved technical scheme of the invention, the thicknesses of the hollow tube and the helical blades are both larger than 2mm.
In order to achieve the technical purpose, the invention adopts another technical scheme that:
a frequency modulation method of a continuously frequency-adjustable ventilating sound insulation structure based on Fano resonance comprises the following steps:
(1) In the controller, the initial helical blade is screwed into the depth t in advance 0 Corresponding resonant frequency f 0 And the angle theta rotated by the motor gear 0 Performing an assignment in which the initial screw blade screw-in depth t 0 The maximum depth to which the helical blade is screwed into the cube base;
(2) The microphone collects noise of the external environment in real time, and the microphone sends collected data to the microprocessor;
(3) The microprocessor adopts FFT conversion method to analyze noise frequency and extract main frequency f in noise frequency 1 Judging the dominant frequency f 1 Whether the noise reduction frequency range is within the structural noise reduction frequency range or not, if not, ending the program; otherwise, the microprocessor will have a main frequency f 1 Sending to a controller;
(4) The controller will master frequency f 1 The value of (2) is substituted into a control equation as sound insulation frequency, and the angle theta rotated by the motor gear is calculated 1 If Δθ=θ 1 -θ 0 And (2) not less than 0, the controller controls the motor to rotate forwards by an angle delta theta, and if delta theta=theta 1 -θ 0 If the value is less than 0, the controller controls the motor to reverse the delta theta angle, and after the motor executes the instruction, the controller reassigns the value, namely theta 0 ＝θ 1 ，f 0 ＝f 1 The method comprises the steps of carrying out a first treatment on the surface of the Circularly executing the steps (2) to (4);
(5) When the controller issues a termination program command, the controller controls the motor to rotate to an initial position.
As a further improved technical solution of the present invention, the control equation is:
Figure SMS_1
wherein θ represents the angle through which the motor gear rotates, i 12 Representing the transmission ratio of the first synchronous belt, c 0 The sound velocity in the air is represented by β, the pitch of the screw through hole of the cube base is represented by P, the pitch of the screw blade is represented by f, and the sound insulation frequency is represented by f.
The beneficial effects of the invention are as follows:
the continuous frequency-adjustable ventilation sound insulation structure based on the Fano resonance principle comprises a plurality of ventilation sound insulation units, wherein each ventilation sound insulation unit comprises a hollow channel formed by a spiral channel and a through hole, sound waves in the double channels are mutually coupled under certain specific frequencies to generate Fano resonance to realize sound insulation, and air in the double channels freely circulates to ensure good ventilation performance. The frequency modulation mechanism screws the matched helical blade into corresponding threads, the length of the helical acoustic wave channel is adjusted, the sound insulation frequency is changed, and the larger the screw-in depth of the helical blade is, the longer the acoustic wave coiling path is, the lower the sound insulation frequency is; and the screwing-in and screwing-out process of the helical blade is continuous, which means that the sound insulation frequency is continuously adjustable. The continuous frequency-adjustable ventilation and sound insulation structure formed by the ventilation and sound insulation units has the advantages of convenience in installation, simplicity in frequency modulation method, good ventilation and sound insulation effect, thin thickness, light weight, high strength and the like, and has great application potential in building acoustics.
Drawings
FIG. 1 is a schematic diagram of a continuously tunable frequency ventilated sound insulation structure (back-side) based on Fano resonance in accordance with the present invention.
Fig. 2 is a schematic diagram of a Fano resonance-based continuously tunable ventilation and sound insulation structure (sound receiving surface) of the present invention.
FIG. 3 is a schematic diagram of a ventilation and sound insulation unit of a Fano resonance based continuously tunable ventilation and sound insulation structure of the present invention.
FIG. 4 is a schematic diagram of a hollow tube welded gear of a Fano resonance-based continuously tunable ventilating sound insulation structure of the present invention.
FIG. 5 is a schematic diagram of a frequency modulation mechanism of a continuously tunable ventilating sound insulation structure based on Fano resonance in accordance with the present invention.
FIG. 6 is a schematic diagram of a Fano resonance-based continuously tunable ventilating sound insulation structure actuation control system of the present invention.
FIG. 7 is a schematic diagram II of the Fano resonance-based drive control system for the continuously tunable, ventilated sound insulation structure of the present invention.
Fig. 8 (a) is a schematic diagram of the dimensions of a ventilation and sound insulation unit of the Fano resonance-based continuously tunable ventilation and sound insulation structure of the present invention.
Fig. 8 (b) is a schematic diagram of the dimensions of a ventilation and sound insulation unit of the Fano resonance-based continuously tunable ventilation and sound insulation structure of the present invention.
Fig. 9 (a) is a schematic diagram of a frequency modulation process of the Fano resonance-based continuous frequency-modulated ventilation and sound insulation structure of the present invention.
Fig. 9 (b) is a schematic diagram two of the frequency modulation process of the Fano resonance-based continuous frequency-modulated ventilation and sound insulation structure of the present invention.
FIG. 10 is a flow chart of adaptive frequency modulation of a Fano resonance-based continuously tunable ventilating sound insulation structure of the present invention.
FIG. 11 is a plot of motor corner versus sound isolation frequency for an embodiment of a Fano resonance-based continuously tunable ventilating sound isolation structure of the present invention.
FIG. 12 is a graph showing sound insulation curves when a motor of an embodiment of the Fano resonance-based continuously tunable ventilating sound insulation structure drives a helical blade to rotate into different angles.
Reference numerals:
1. a ventilation and sound insulation unit; 2. a frequency modulation mechanism; 3. a data acquisition and analysis system; 4. controlling a driving system; 101. a cube base; 102. a hollow tube; 103. a helical blade; 104. a through hole; 201. a gear; 202. a synchronous belt; 301. a microphone; 302. an angle sensor; 303. a microprocessor; 401. a motor gear; 402. a first synchronization belt; 403. a motor gear base; 404. a motor; 405. and a controller.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Fig. 1 and 2 are schematic diagrams of a sound receiving surface and a back sound surface of a Fano resonance-based continuous tunable ventilation and sound insulation structure of the present invention, which includes a ventilation and sound insulation wall, a frequency modulation mechanism 2, a data acquisition and analysis system 3, and a control driving system 4.
Referring to fig. 3 and 4, the ventilation and sound insulation wall is formed by connecting a plurality of ventilation and sound insulation units 1, wherein the ventilation and sound insulation units 1 comprise a cube base 101, a hollow tube 102 and a spiral blade 103, the spiral blade 103 is fixedly connected to the outer wall of the hollow tube 102, a cylindrical through hole 104 is formed in the middle of the cube base 101, internal threads matched with parameters of the spiral blade 103 are distributed on the inner wall of the through hole 104, the spiral blade 103 can be screwed into and screwed out of the threaded through hole 104 anticlockwise, a spiral air channel is surrounded by the outer wall of the hollow tube 102, the spiral blade 103 and the through hole wall on the cube base 101, and sound waves and air flow enter and exit from the hollow tube 102 and the spiral air channel.
Referring to fig. 4 and 5, the frequency modulation mechanism 2 includes a plurality of gears 201 and a plurality of synchronous belts 202, the outer side of the end portion of each hollow tube 102 is fixedly connected with a gear 201, the synchronous belts 202 are toothed belts, and the belt teeth of the synchronous belts 202 are meshed with two adjacent gears 201. In operation, the toothed belt 202 drives the gear 201 outside the end of the hollow tube 102 to rotate.
Referring to fig. 2 and 6, the data acquisition and analysis system 3 includes an angle sensor 302, a microphone 301, and a microprocessor 303. The microphone 301 is fixedly connected to the sound receiving surface of the ventilation and sound insulation structure at a position close to the middle, and is used for collecting noise of the external environment. The angle sensor 302 is installed at the axial center of the motor gear 401, and is used for detecting the rotation angle data of the motor gear 401 and sending the rotation angle data to the microprocessor 303. The microprocessor 303 is fixedly connected to the motor gear base 403, and is configured to receive the noise collected by the microphone 301, analyze and calculate the noise, and send the main frequency of the analyzed and calculated noise frequency to the controller 405.
Referring to fig. 6 and 7, the control driving system 4 includes a motor gear base 403, a motor 404, a motor gear 401, a first synchronous belt 402, and a controller 405, where the motor gear base 403 is fixedly connected to a ventilation and sound insulation wall, the motor 404 and the controller 405 are both fixedly connected to the motor gear base 403, and the controller 405 is configured to receive data sent by the microprocessor 303, and convert a main frequency value into an angle through which the motor gear 401 rotates by using a control equation, so as to drive the motor 404 to rotate. An output shaft of the motor 404 is connected with a motor gear 401 through a coupling, and the motor gear 401 is connected with the gear 201 on the hollow tube 102 through a first synchronous belt 402. The motor 404 is used for driving the first synchronous belt 402 to rotate and further driving all synchronous belts 202 in the frequency modulation mechanism 2 to rotate together, and finally driving all the spiral blades 103 to rotate, so that the spiral blades 103 are screwed into or screwed out of the cube base 101, and the sound insulation frequency is adjusted.
The angle sensor 302 and the microphone 301 are both connected to a microprocessor 303, the microprocessor 303 is connected to a controller 405, and the controller 405 is connected to a motor 404. The angle sensor 302, microphone 301, processor, controller 405 and motor 404 are all connected to an external power source.
The sound insulation frequency of the ventilation and sound insulation structure is changed through the frequency modulation mechanism 2, the synchronous belt 202 drives the gear 201 on the hollow tube 102 to rotate, the matched spiral blade 103 is screwed into the internal threaded hole of the cube base 101 anticlockwise, the screwing depth is equal to the thickness of the ventilation and sound insulation unit 1, and under the condition that the screw pitch is unchanged, the larger the screwing depth is, the longer the path of the sound wave coiling is, and the lower the sound insulation frequency is; and the process of screwing in and screwing out the spiral blade 103 is continuous, meaning that the sound insulation frequency is continuously adjustable.
All gears 201 and synchronous belts 202 in the frequency modulation mechanism 2 have the same size parameters, so that each ventilation and sound insulation unit 1 can have the same parameter variation in the frequency modulation process, and the sound insulation frequency of all sound insulation units is consistent with the target frequency.
The thickness of the hollow tube 102 and the helical blades 103 is greater than 2mm so as to avoid acoustic-solid coupling.
Compare (a) and (b) in FIG. 8, where r 1 Radius r of hollow tube 102 2 The radius of the cylindrical through hole 104 of the cube base 101, t is the height of the spiral channel, or the depth of screwing the spiral blade 103 into the cube base 101; r is (r)<r 1 Is an air channel, r 1 <r<r 2 Is a spiral channel. Acoustic wave at r<r 1 The distance in the area is a straight line, so that continuous transmission is maintained, and sound waves with any frequency can be transmitted; acoustic wave at r 1 <r<r 2 The path in the region of (2) is a spiral line, obviously, the sound wave path in the spiral channel is prolonged, the equivalent sound velocity is reduced, the high refractive index is caused, and only sound waves meeting the resonance frequency of the spiral channel can penetrate, so that the sound waves in the spiral channel are in a discrete resonance state; at the position ofThe emission end of the sound wave, the sound wave in a discrete resonance state and the sound wave in a continuous state interfere to cause zero transmittance, and the transmission spectrum of the sound wave is an asymmetric Fano line type, so that the sound insulation mechanism is called as being based on Fano resonance, and the sound insulation frequency of the ventilation sound insulation unit 1 is the frequency of Fano resonance. The Fano resonance conditions are:
Figure SMS_2
in n r At r is sound wave 1 <r<r 2 In the region of (2), lambda is the wavelength of the sound wave, let the helix angle of the helical channel be beta, the effective refractive index is:
Figure SMS_3
the relationship between the height t of the spiral channel and the Fano resonance frequency, that is, the relationship between the depth of screwing the spiral blade 103 and the sound insulation frequency f is:
Figure SMS_4
wherein, c 0 Is the speed of sound in air. In the present invention, the helix angle β of the internal thread of the through hole 104 in the screw blade 103 and the cube base 101 is fixed, so that the depth of screwing the screw blade 103 into the cube base 101 (i.e., the height of the screw channel) can be changed, i.e., the sound insulation frequency can be changed.
Let the pitch of the spiral blade 103 be P, the height of the corresponding spiral channel be P/sin beta when the spiral blade 103 rotates one revolution
Figure SMS_5
The angle, the screw blade 103 is screwed in to a depth of +.>
Figure SMS_6
Thus the rotation angle of the helical blade 103
Figure SMS_7
The relation with the sound insulation frequency f is:
Figure SMS_8
according to the above formula, the sound insulation frequency of the ventilation sound insulation structure can be adjusted, if the main frequency of noise is f, the spiral blade 103 rotates to a corresponding angle, a spiral channel with a corresponding height can be obtained, and Fano resonance with a corresponding frequency occurs in the structure.
If the transmission ratio of the first synchronous belt 402 is i 12 The relationship between the angle θ rotated by the motor gear 401 and the sound insulation frequency f, namely, the control equation is:
Figure SMS_9
when the microphone 301 detects a change in the dominant frequency of the incident sound wave, the motor 404 at that frequency should rotate by an angle θ as shown in the control equation (5) 2 Angle θ to the current position 1 Is not zero, the controller 405 determines (θ 2 -θ 1 ) To control the amount of rotation of motor 404 and the amount of angle to be rotated. Fig. 9 (a) and 9 (b) are schematic diagrams of the frequency modulation process, the motor 404 drives the first synchronous belt 402 to rotate, the gear 201 on each ventilation and sound insulation unit 1 is meshed with the corresponding synchronous belt 202 in a toothed manner, and the synchronous rotation (θ 2 -θ 1 ) Angle, change of screw depth of the screw blade 103 (t 2 -t 1 ) The frequency modulation process from fig. 9 (a) to fig. 9 (b) is such that the screw blade 103 rotates counterclockwise, the screw depth increases, and the noise reduction frequency gradually decreases.
FIG. 10 is a flowchart of a continuous frequency modulation process of the present invention, wherein the initial screw blade 103 screw-in depth t is initially assigned 0 Corresponding resonant frequency f 0 And the angle theta rotated by the motor gear 401 0 (i.e., the angle through which motor 404 rotates), the initial t of the present routine 0 For the maximum depth of screwing of the screw blade 103. The program first gives an initial rotation angle theta 0 And a value f of the initial frequency 0 MicrophoneWind 301 begins to collect data, which is transformed by the FFT of microprocessor 303, analyzes the noise frequency and extracts the dominant frequency f 1 Judging whether the frequency of the required noise reduction is within the structural noise reduction range, if not, ending the program, otherwise, calculating the corresponding theta by a control equation, namely a formula (5) 1 If Δθ=θ 1 -θ 0 Not less than 0, the motor 404 rotates forward by an angle delta theta, or rotates backward, the motor 404 executes the instruction, the program reassigns value theta 0 ＝θ 1 ，f 0 ＝f 1 Then driving the motor 404 to rotate according to the detected noise frequency; when a terminate program command is issued, the program controls the motor 404 to rotate back to the initial position.
From the above, the frequency modulation method of the continuously adjustable frequency ventilation and sound insulation structure based on Fano resonance specifically comprises the following steps:
step (1), in the controller 405, the initial screw blade 103 is screwed into the depth t in advance 0 Corresponding resonant frequency f 0 And the angle theta rotated by the motor gear 401 0 Assignment is made in which the initial helical blade 103 is screwed into depth t 0 For the maximum depth of screwing of the helical blade 103 into the cube base 101;
step (2), the microphone 301 collects noise of the external environment in real time, and the microphone 301 sends collected data to the microprocessor 303;
step (3), the microprocessor 303 analyzes the noise frequency by adopting the FFT method and extracts the dominant frequency f in the noise frequency 1 Judging the dominant frequency f 1 Whether the noise reduction frequency range is within the structural noise reduction frequency range or not, if not, ending the program; otherwise, the microprocessor 303 will generate the main frequency f 1 To the controller 405;
step (4), the controller 405 outputs the main frequency f 1 The value of (2) is substituted into a control equation (formula 5) as sound insulation frequency, and the angle theta rotated by the motor gear 401 is calculated 1 If Δθ=θ 1 -θ 0 Not less than 0, the controller 405 controls the motor 404 to rotate forward by an angle Δθ, and if Δθ=θ 1 -θ 0 If less than 0, the controller 405 controls the motor 404 to reverse the delta theta angle, and after the motor 404 executes the instruction, the controller 405 reassigns the value of theta 0 ＝θ 1 ，f 0 ＝f 1 The method comprises the steps of carrying out a first treatment on the surface of the Circularly executing the steps (2) to (4);
in step (5), when the controller 405 issues a termination program command, the controller 405 controls the motor 404 to rotate to an initial position, i.e., a position at which the screw blade 103 is screwed into the cube base 101 to a maximum depth.
Examples: the acoustic performance simulation of the continuously tunable ventilated sound insulation structure of the present invention was performed using a pressure acoustic module in multi-physical field software COMSOL Multiphysics. Radius r of helical blade 103 1 Radius r of hollow tube 102 =50mm 2 Height t of helical blade 103 =30mm 0 Pitch p=54 mm, helix angle β=9.7°, sound velocity in air c 0 =343 m/s. The transmission ratio i of the first timing belt 402 in this embodiment 12 =1, the screw blades 103 are all screwed into and out of the cube base 101, the height of the corresponding screw blade 103 can be in the range of 0-58 mm, and the angle θ=0-2.15 pi or θ=0-3870 that the motor gear 401 needs to rotate. Fig. 11 shows the relationship between the sound insulation frequency f and the angle θ required to rotate the motor gear 401 in this embodiment, in the simulation calculation, the motor 404 drives the frequency modulation mechanism 2 to make the screw blade 103 screw in to a depth of 13.5 mm-58 mm, the angle required to rotate the corresponding screw blade 103 is 0.5 pi-2.15 pi, and under the condition that the transmission ratio is equal to 1, the angle θ required to rotate the motor gear 401 is also 0.5 pi-2.15 pi, and as can be seen from the figure, the corresponding sound insulation frequency range is 500-2200 Hz.
Fig. 12 shows the sound insulation curves corresponding to the screw blades 103 screwed into different angles. In the drawing, the screw blade 103 is screwed in from 290 degrees to 340 degrees and 380 degrees, and the corresponding screw blade 103 is screwed in to the depths of 43.5mm, 51mm and 57mm, and it is obvious from the drawing that the larger the screw blade 103 is screwed in, the lower the sound insulation frequency is.
Fig. 12 shows the sound insulation mechanism and sound insulation effect of a Fano resonance-based ventilation sound insulation structure. Referring to fig. 8, the sound wave is incident on the hollow tube 102 and can be transmitted completely, the spiral channel is a long and narrow cavity, only the sound wave meeting the resonant frequency of the cavity can be transmitted, when the two channels are combined, a coupling structure is formed, when the sound wave passes through the coupling structure, the sound insulation amount is in an asymmetric Fano line shape, and the asymmetric resonance can generate two anti-resonance points behind the complete transmission peak. Taking a curve with θ=380° as an example, the total transmission peak is 460Hz, the frequencies of two antiresonance points are 510Hz and 916Hz respectively, and the sound waves are totally reflected at the two frequencies, so that sound insulation is realized, and the sound insulation amount is up to 45dB; in addition, in the range of 510 Hz-916 Hz, the sound insulation amount basically reaches 10dB, and the noise in the frequency range can be attenuated to a certain degree.
Finally, it should be noted that the above description is only for illustrating the technical solution of the present invention, and not for limiting the scope of the present invention, and that the simple modification and equivalent substitution of the technical solution of the present invention can be made by those skilled in the art without departing from the spirit and scope of the technical solution of the present invention.

Claims (7)

1. A continuously adjustable frequency ventilation sound insulation structure based on Fano resonance is characterized in that: the system comprises a ventilation sound insulation wall, a frequency modulation mechanism, a data acquisition and analysis system and a control driving system;
the ventilation sound insulation wall is formed by connecting a plurality of ventilation sound insulation units, wherein each ventilation sound insulation unit comprises a cube base, a hollow tube and a spiral blade, the spiral blade is fixedly connected to the outer wall of the hollow tube, a through hole is formed in the middle of the cube base, threads matched with the spiral blade are distributed on the inner wall of the through hole, the spiral blade can be screwed in and screwed out of the through hole, a spiral channel is formed by the outer wall of the hollow tube, the spiral blade and the through hole wall on the cube base in a surrounding mode, and sound waves and air flow enter and exit from the hollow tube and the spiral channel;
the frequency modulation mechanism comprises a plurality of gears and a plurality of synchronous belts, each gear is fixedly connected to the outer side of the end part of the hollow tube, each synchronous belt is a toothed belt, and the belt teeth of each synchronous belt are meshed with two adjacent gears;
the data acquisition and analysis system comprises a microphone and a microprocessor, wherein the microphone is fixedly connected to the sound receiving surface of the ventilation sound insulation wall, and the microprocessor is fixedly connected to the motor gear base;
the control driving system comprises a motor gear base, a motor gear, a first synchronous belt and a controller, wherein the motor gear base is fixedly connected to a ventilation and sound insulation wall, the motor and the controller are fixedly connected to the motor gear base, an output shaft of the motor is connected with the motor gear, and the motor gear is connected with a gear on the hollow pipe through the first synchronous belt;
the microphone is connected with the microprocessor, the microprocessor is connected with the controller, and the controller is connected with the motor.
2. The Fano resonance-based continuously tunable ventilating sound insulation structure of claim 1, wherein: the data acquisition and analysis system further comprises an angle sensor, an output shaft of the motor is connected with the motor gear through a coupler, an end part of a shaft at the center of the motor gear is fixedly connected with the angle sensor, the angle sensor is connected with the microprocessor, and the angle sensor is used for detecting corner data of the motor gear and sending the corner data to the microprocessor.
3. The Fano resonance-based continuously tunable ventilating sound insulation structure of claim 1, wherein: the microphone is used for collecting noise of the external environment; the microprocessor is used for receiving the noise collected by the microphone, analyzing and calculating, and sending the main frequency in the analyzed and calculated noise frequency to the controller; the controller is used for receiving data sent by the microprocessor, converting a main frequency value into an angle through which a motor gear rotates through a control equation and then driving the motor to rotate; the motor is used for driving the first synchronous belt to rotate so as to drive all synchronous belts in the frequency modulation mechanism to rotate together, and finally drives the helical blade to rotate, so that the helical blade is screwed into or out of the cube base, and the sound insulation frequency is adjusted.
4. The Fano resonance-based continuously tunable ventilating sound insulation structure of claim 1, wherein: the through hole is cylindrical.
5. The Fano resonance-based continuously tunable ventilating sound insulation structure of claim 1, wherein: the thickness of the hollow tube and the helical blade is more than 2mm.
6. The Fano resonance-based frequency modulation method for a continuously tunable ventilating sound insulation structure of claim 1, wherein: the method comprises the following steps:
(1) In the controller, the initial helical blade is screwed into the depth t in advance 0 Corresponding resonant frequency f 0 And the angle theta rotated by the motor gear 0 Performing an assignment in which the initial screw blade screw-in depth t 0 The maximum depth to which the helical blade is screwed into the cube base;
(2) The microphone collects noise of the external environment in real time, and the microphone sends collected data to the microprocessor;
(3) The microprocessor adopts FFT conversion method to analyze noise frequency and extract main frequency f in noise frequency 1 Judging the dominant frequency f 1 Whether the noise reduction frequency range is within the structural noise reduction frequency range or not, if not, ending the program; otherwise, the microprocessor will have a main frequency f 1 Sending to a controller;
(4) The controller will master frequency f 1 The value of (2) is substituted into a control equation as sound insulation frequency, and the angle theta rotated by the motor gear is calculated 1 If Δθ=θ 1 -θ 0 And (2) not less than 0, the controller controls the motor to rotate forwards by an angle delta theta, and if delta theta=theta 1 -θ 0 If the value is less than 0, the controller controls the motor to reverse the delta theta angle, and after the motor executes the instruction, the controller reassigns the value, namely theta 0 ＝θ 1 ，f 0 ＝f 1 The method comprises the steps of carrying out a first treatment on the surface of the Circularly executing the steps (2) to (4);
(5) When the controller issues a termination program command, the controller controls the motor to rotate to an initial position.
7. The Fano resonance-based frequency modulation method for a continuously tunable ventilating sound insulation structure of claim 6, wherein: the control equation is:
Figure FDA0004001944050000021
wherein θ represents the angle through which the motor gear rotates, i 12 Representing the transmission ratio of the first synchronous belt, c 0 The sound velocity in the air is represented by β, the pitch of the screw through hole of the cube base is represented by P, the pitch of the screw blade is represented by f, and the sound insulation frequency is represented by f.
CN202211620699.2A 2022-12-15 2022-12-15 Continuous frequency-adjustable ventilation sound insulation structure based on Fano resonance and frequency modulation method Active CN116045414B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211620699.2A CN116045414B (en) 2022-12-15 2022-12-15 Continuous frequency-adjustable ventilation sound insulation structure based on Fano resonance and frequency modulation method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211620699.2A CN116045414B (en) 2022-12-15 2022-12-15 Continuous frequency-adjustable ventilation sound insulation structure based on Fano resonance and frequency modulation method

Publications (2)

Publication Number Publication Date
CN116045414A true CN116045414A (en) 2023-05-02
CN116045414B CN116045414B (en) 2023-06-20

Family

ID=86113860

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211620699.2A Active CN116045414B (en) 2022-12-15 2022-12-15 Continuous frequency-adjustable ventilation sound insulation structure based on Fano resonance and frequency modulation method

Country Status (1)

Country Link
CN (1) CN116045414B (en)

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104575484A (en) * 2014-12-30 2015-04-29 北京市劳动保护科学研究所 Controllable compound sound absorption structure
CN108301921A (en) * 2017-01-11 2018-07-20 上海怡允环境科技有限公司 A kind of sound insulation of engine, noise reduction, exhaust treatment system
CN108800517A (en) * 2018-08-29 2018-11-13 正升环境科技股份有限公司 Spread resonance muffler device and vent passages sound-attenuating system
JP6491787B1 (en) * 2017-12-06 2019-03-27 富士フイルム株式会社 Soundproof system
CN110211560A (en) * 2019-05-31 2019-09-06 广东美的制冷设备有限公司 Resonance sound-absorbing structure and air-conditioning draught fan component
CN110322868A (en) * 2019-06-06 2019-10-11 江苏科技大学 A kind of driving frequency-conversion Helmholz resonance device and its frequency modulation noise-reduction method
CN111561252A (en) * 2020-04-01 2020-08-21 同济大学 Broadband ventilation sound insulation window unit structure and application thereof
US20200349914A1 (en) * 2018-02-27 2020-11-05 Fujifilm Corporation Soundproof structure
CN111926933A (en) * 2019-12-24 2020-11-13 南京林业大学 Frequency-adjustable sound absorption plate based on Helmholtz resonator
CN112435646A (en) * 2019-08-26 2021-03-02 凌波怡声科技(深圳)有限公司 Acoustic metamaterial large-area short-channel broadband ventilation sound insulator and barrier
CN214657903U (en) * 2020-12-22 2021-11-09 南京林业大学 Frequency-adjustable sound-absorbing panel
CN214705424U (en) * 2020-12-22 2021-11-12 南京林业大学 Ventilation sound insulation barrier based on destructive interference
CN217236051U (en) * 2022-04-02 2022-08-19 宁波坤博测控科技有限公司 Ventilation noise eliminator
CN115162919A (en) * 2022-07-08 2022-10-11 上海申华声学装备有限公司 Sound insulation ventilation energy-saving window

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104575484A (en) * 2014-12-30 2015-04-29 北京市劳动保护科学研究所 Controllable compound sound absorption structure
CN108301921A (en) * 2017-01-11 2018-07-20 上海怡允环境科技有限公司 A kind of sound insulation of engine, noise reduction, exhaust treatment system
JP6491787B1 (en) * 2017-12-06 2019-03-27 富士フイルム株式会社 Soundproof system
US20200349914A1 (en) * 2018-02-27 2020-11-05 Fujifilm Corporation Soundproof structure
CN108800517A (en) * 2018-08-29 2018-11-13 正升环境科技股份有限公司 Spread resonance muffler device and vent passages sound-attenuating system
CN110211560A (en) * 2019-05-31 2019-09-06 广东美的制冷设备有限公司 Resonance sound-absorbing structure and air-conditioning draught fan component
CN110322868A (en) * 2019-06-06 2019-10-11 江苏科技大学 A kind of driving frequency-conversion Helmholz resonance device and its frequency modulation noise-reduction method
CN112435646A (en) * 2019-08-26 2021-03-02 凌波怡声科技(深圳)有限公司 Acoustic metamaterial large-area short-channel broadband ventilation sound insulator and barrier
CN111926933A (en) * 2019-12-24 2020-11-13 南京林业大学 Frequency-adjustable sound absorption plate based on Helmholtz resonator
CN111561252A (en) * 2020-04-01 2020-08-21 同济大学 Broadband ventilation sound insulation window unit structure and application thereof
CN214657903U (en) * 2020-12-22 2021-11-09 南京林业大学 Frequency-adjustable sound-absorbing panel
CN214705424U (en) * 2020-12-22 2021-11-12 南京林业大学 Ventilation sound insulation barrier based on destructive interference
CN217236051U (en) * 2022-04-02 2022-08-19 宁波坤博测控科技有限公司 Ventilation noise eliminator
CN115162919A (en) * 2022-07-08 2022-10-11 上海申华声学装备有限公司 Sound insulation ventilation energy-saving window

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
牛亚文: "可实现宽频隔声的全向通风铁路声屏障", 浙 江 大 学 学 报(工学版), vol. 55, no. 6, pages 1048 - 1055 *
王俪静: "声学超材料在绿色建筑通风隔声中的应用展望", 林业机械与木工设备, vol. 50, no. 10, pages 13 - 21 *

Also Published As

Publication number Publication date
CN116045414B (en) 2023-06-20

Similar Documents

Publication Publication Date Title
CN203549259U (en) Frequency-adjustable micro-perforated pipe muffler with variable-volume expanding cavity
CN103486394A (en) Variable-frequency microperforated pipe silencer with variable perforation section lengths
CN116045414B (en) Continuous frequency-adjustable ventilation sound insulation structure based on Fano resonance and frequency modulation method
US8287228B2 (en) System and methods for controlling the amplitude modulation of noise generated by wind turbines
WO2007073469A3 (en) Wide bandwidth farms for capturing wave energy
CN110322868A (en) A kind of driving frequency-conversion Helmholz resonance device and its frequency modulation noise-reduction method
CN103807996B (en) Muffler
CN112799077A (en) Sonar detecting system based on water pipeline
CN113241052B (en) Spiral curled underwater sound absorption super-surface structure
CN108279579B (en) A kind of Large Underwater platform noise reduction system with class cochlear structures
CN204026027U (en) A kind of plug-in type Reed bore muffler
CN210318438U (en) Noise reduction type multi-shaft output speed reducer
CN115874733B (en) Ventilating sound insulation wall with autonomous frequency modulation function and autonomous frequency modulation method
CN102322905B (en) Transducer driving circuit of ultrasonic flow meter
CN111503410A (en) Helmholtz type silencer
CN210068266U (en) Adjustable expansion cavity type silencer
CN203035342U (en) Mute type diesel power unit
CN112963330A (en) Air compressor machine silencer that admits air
CN202129238U (en) Ultrasonic scale removing device of sewage source heat pump system
CN110751938A (en) Helmholtz resonator and working method thereof
CN202939159U (en) Ultrasonic concrete detector probe
CN102866206A (en) Ultrasonic concrete detection probe
CN210688650U (en) Bionic noise-reduction air conditioner grille
CN214221333U (en) Air inlet and exhaust device of low-noise diesel generating set
CN108801444B (en) Array type thermoacoustic generator

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
GR01 Patent grant
GR01 Patent grant