CN113012538B - Device and method for controlling pneumatic suspended particulate matters by sound waves - Google Patents
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Abstract
The invention discloses a device and a method for controlling pneumatic suspended particles by sound waves, which are characterized by comprising a signal generator capable of generating sine wave audio, a power amplifier, two identical Helmholtz sound sources arranged at two ends of a waveguide tube and pneumatic suspended particles placed in the waveguide tube. The critical voltage amplitude of the transition of the pneumatic suspended particles from the fluidized particle aggregation state to the stripe particle aggregation state is determined, the sound radiation force and the secondary radiation force of the pneumatic suspended particles are balanced and modulated in the numerical range lower/higher than the critical voltage amplitude, the discrete distribution characteristics of the stripe particle aggregation and the fluidized particle aggregation are regulated and controlled, a large number of particles are subjected to ordered static or dynamic particle stripe aggregation process, or fluidized adjustable particle swarm migration is carried out in a gas medium standing wave space, and the collision, aggregation, sedimentation, removal, mixing, crushing, fluidization and transmission processes of the pneumatic suspended particles are improved.
Description
Technical Field
The invention relates to a device and a method for controlling pneumatic suspended particles by sound waves, and belongs to the field of pneumatic suspended particle control.
Background
The device and the system which can flexibly and contactlessly control the complex movement and evolution behaviors (including agglomeration, crushing, suspension, collision, sedimentation, removal, transmission and the like) of the suspended particles are developed, and are important subjects of important focus in the field of particle science, and have great significance in guiding the industrial production application of utilizing the particles.
Disclosure of Invention
The invention aims to: in order to overcome the problems in the prior art, the invention provides a device and a method for controlling pneumatic suspended particles by sound waves.
The technical scheme is as follows: in order to achieve the above purpose, the invention adopts the following technical scheme:
the utility model provides a device of pneumatic suspended particulate matter is controlled to sound wave which characterized in that: the device comprises a signal generator capable of generating sine wave audio, a power amplifier, a waveguide tube, two identical Helmholtz sound sources arranged at two ends of the waveguide tube and pneumatic suspended particles placed in the waveguide tube;
the Helmholtz sound source comprises a loudspeaker and a Helmholtz resonator, and the Helmholtz resonator is positioned between the waveguide port and the loudspeaker;
the signal generator, the power amplifier and the loudspeaker are connected in sequence and form a closed electrical loop;
the signal generator outputs an audio signal with adjustable frequency and voltage amplitude, after the voltage is increased by the power amplifier, an alternating current electric signal is supplied to a loudspeaker of a Helmholtz sound source, and a small-amplitude sound wave generated by the loudspeaker is amplified by the Helmholtz resonator and then a standing wave sound field is generated in the waveguide tube;
the frequency of the audio signal output by the signal generator is one of a plurality of orders of resonance frequencies of the waveguide tube obtained through experiments, and the frequency regulation and control range is 1 Hz-20000 Hz; the sound pressure amplitude regulation range of the sound field in the waveguide tube is 0 Pa-1500 Pa.
Preferably:
the input voltage amplitude of the speaker includes a particular threshold voltage amplitude;
when the input voltage amplitude of the loudspeaker is lower than the critical voltage amplitude, the pneumatic suspended particles migrate and aggregate into discrete stripe particle aggregation groups distributed in a stripe shape in the waveguide tube;
when the input voltage amplitude of the loudspeaker is higher than the critical voltage amplitude, the pneumatic suspended particles migrate, suspend and agglomerate in the waveguide into fluidized particle agglomerates mixed with the gas medium in the waveguide.
Preferably:
the stripe particle aggregation group is in a film sheet shape formed by stacking a plurality of particles and is perpendicular to the transmission direction of sound waves in the waveguide tube;
the fluidized particle aggregate moves integrally in the waveguide tube, and the external contour of the fluidized particle aggregate changes dynamically;
and the fluidized particulate collection clusters are present as a number of discrete collection areas within the waveguide, with particles moving rapidly within the fluidized particulate collection clusters.
Preferably:
the waveguide tube is annular, and the circumference is 978mm;
the critical voltage amplitude is 7V;
the pneumatic suspended particles are cylindrical coke particles generated by rice hull combustion.
A method for controlling pneumatic suspended particulate matters by sound waves, which is characterized by comprising the following steps: comprises the steps of,
1) The actual resonance frequencies of a plurality of orders of the waveguide tube are tested through experiments;
2) The method comprises the steps of taking any first-order resonant frequency of a waveguide tube as the frequency of an audio signal output by a signal generator, changing the voltage amplitude of the audio signal output by the signal generator, inputting the audio signal into a loudspeaker after the voltage of the audio signal is increased by a power amplifier, changing the input voltage amplitude of the loudspeaker, generating a non-uniform standing wave sound field in the waveguide tube after the small-amplitude sound wave generated by the loudspeaker is amplified by a Helmholtz resonator, and observing and recording the behavior evolution characteristics of pneumatic suspended particles in the non-uniform standing wave sound field in the waveguide tube, including the characteristics of collision, agglomeration, suspension, sedimentation, removal, mixing, crushing, fluidization, transmission and the like of the pneumatic suspended particles;
3) Determining the critical voltage amplitude of the transition of the pneumatic suspended particles from the fluidized particle aggregation state to the striped particle aggregation state of the striped stack;
4) In the numerical range lower than the critical voltage amplitude, gradually reducing or increasing the input voltage amplitude of the loudspeaker, balancing and modulating the relative magnitude of the acoustic radiation force and the secondary radiation force received by the pneumatic suspended particles, regulating and controlling the characteristic of the stripe particle aggregation, and improving the collision, agglomeration, sedimentation and removal processes of the pneumatic suspended particles;
in the numerical range higher than the critical voltage amplitude, the input voltage amplitude of the loudspeaker is gradually reduced or increased, the relative magnitude of the acoustic radiation force and the secondary radiation force received by the pneumatic suspended particles is balanced and modulated, the characteristic of the discrete distributed fluidized particle aggregation is regulated and controlled, and the mixing, crushing, fluidization and transmission processes of the pneumatic suspended particles are improved.
The beneficial effects are that: the invention has the remarkable beneficial effects that:
the invention provides a device and a method for controlling pneumatic suspended particles by sound waves, which enable micro particles to undergo the processes of clustered agglomeration, crushing, suspension, collision, sedimentation, removal and transmission. By adjusting the amplitude and frequency of the input voltage of the loudspeaker, a non-uniform sound field with controllable parameters is constructed in the waveguide tube. Under the condition of waveguide resonant frequency, secondary radiation force and acoustic radiation force received by the suspended particles are balanced and modulated by means of the high-low variation of certain specific voltage amplitude, so that complex motion evolution behaviors of the suspended particles in a waveguide space can be flexibly controlled in a contactless manner, and the complex motion evolution behaviors comprise collision-agglomeration-suspension-sedimentation-removal, mixing-crushing-fluidization-transmission and the like. The agglomerated large particles can be directly settled or removed in a particle gas mixed flow state when flowing through a post-stage dust remover. The device and the method not only can be used for many occasions such as environmental protection, energy conversion, particle material preparation and the like, but also can be used as a teaching instrument for demonstrating the behavior characteristics of complex particles such as fluidization, agglomeration, crushing, suspension, collision, sedimentation, removal, transmission and the like of pneumatic suspended particles in a non-uniform sound field.
Drawings
FIG. 1 is a schematic view of an apparatus of the present invention;
FIG. 2 is a schematic illustration of the apparatus and test of the present invention;
FIG. 3 is a schematic diagram of a Helmholtz acoustic source of the present invention;
FIG. 4 is a schematic representation of particle agglomeration at lower voltage amplitudes during operation of the apparatus of the present invention;
in the figure: 1-a signal generator; a 2-power amplifier; 3-waveguide; 4-Helmholtz sound source; 41-a loudspeaker; 42-Helmholtz resonator; 51-striped particle clusters; 511-a first stripe particle agglomeration; 512-second stripe particle clusters; 513-a third stripe particle agglomerate; 52-fluidization of the particle agglomeration; 521-a first fluidised particle aggregation group; 522-second fluidized particle agglomeration.
Detailed Description
The invention will be further described with reference to fig. 1 to 4.
The utility model provides a device of pneumatic suspended particulate matter is controlled to sound wave which characterized in that: comprising a signal generator 1 capable of generating sine wave audio, a power amplifier 2, a waveguide 3, two identical Helmholtz sound sources 4 mounted at both ends of the waveguide 3, and pneumatically suspended particles placed in the waveguide 3.
In which fig. 3 is a schematic view of a Helmholtz acoustic source 4 according to the present invention, the Helmholtz acoustic source 4 includes a speaker 41 and a Helmholtz resonator 42 having a smaller inner diameter of a bandpass hole, and the Helmholtz resonator 42 is located between a port of the waveguide 3 and the speaker 41.
Wherein the signal generator 1, the power amplifier 2 and the speaker 41 are connected in sequence and form a closed electrical loop.
The signal generator 1 outputs an audio signal with adjustable frequency and voltage amplitude, the power amplifier 2 supplies an alternating current signal to the loudspeaker 41 in the Helmholtz sound source 4 after the audio signal is boosted by the power amplifier 2, and a standing wave sound field is generated in the waveguide tube 3 after a small-amplitude sound wave generated by the loudspeaker 41 is amplified by the Helmholtz resonator 42.
The frequency of the audio signal output by the signal generator 1 is one of a plurality of orders of resonance frequencies of the waveguide tube 3 obtained through experiments, and the frequency regulation and control range is 1 Hz-20000 Hz; the sound pressure amplitude regulation range of the sound field in the waveguide tube 3 is 0 Pa-1500 Pa.
The input voltage amplitude of the speaker 41 includes a specific threshold voltage amplitude.
When the input voltage amplitude of the speaker 41 is lower than the threshold voltage amplitude, the pneumatically suspended particles migrate and aggregate into discrete striped particle aggregates 51 distributed in a striped manner in the waveguide 3.
Wherein when the input voltage amplitude of the speaker 41 is higher than the threshold voltage amplitude, the pneumatically suspended particles migrate, suspend, and agglomerate in the waveguide 3 into fluidized particle agglomerates 52 that are well mixed with the gaseous medium in the waveguide 3.
Wherein the striped particle aggregation 51 is in the form of a thin film sheet composed of a plurality of stacked particles, perpendicular to the transmission direction of the acoustic wave in the waveguide.
Wherein the fluidized particle aggregate 52 moves throughout the waveguide 3 and its outer contour changes dynamically.
Wherein the fluidized particulate clusters 52 present a number of discrete aggregation areas within the waveguide 3, the particles moving rapidly within the fluidized particulate clusters 52.
Preferably, the waveguide 3 is annular with a circumference of 978mm.
Preferably, the threshold voltage amplitude is about 7V.
Preferably, the pneumatically suspended particles are cylindrical coke particles produced by the combustion of rice hulls.
A method for controlling pneumatic suspended particulate matters by sound waves, which is characterized by comprising the following steps: the method comprises the following steps:
1) The actual several orders of resonance frequencies of the waveguide were experimentally measured.
2) The resonance frequency of one waveguide tube measured by the experiment is randomly selected as the output frequency of the signal generator, the input voltage amplitude of the loudspeaker is changed, and the behavior evolution characteristics of the pneumatic suspended particles in the nonuniform standing wave sound field in the waveguide tube are observed and recorded, including the characteristics of collision, agglomeration, suspension, sedimentation, removal, mixing, crushing, fluidization, transmission and the like of the pneumatic suspended particles.
3) The threshold voltage amplitude at which the pneumatically-suspended particles transition from the fluidized particle agglomerate state to the fringe-shaped stacked discrete particle agglomerate state is determined.
4) In the numerical range lower than the critical voltage amplitude, gradually reducing or increasing the input voltage amplitude of the loudspeaker, balancing and modulating the relative magnitude of the acoustic radiation force and the secondary radiation force received by the pneumatic suspended particles, regulating and controlling the characteristics (such as geometric thickness, height, width and the like) of the stripe particle aggregation groups, and improving the collision, agglomeration, sedimentation and removal processes of the pneumatic suspended particles;
the definition of the acoustic radiation force is:
for the actual suspended small particles equivalent to a spherical structure and with the sphere radius far smaller than the wavelength of sound waves, in a fluid calibrated by a space Cartesian three-dimensional rectangular coordinate system, the sound field generates sound radiation force on the single small particles
Can be expressed as:
in the method, in the process of the invention,
unit vectors corresponding to x, y and z coordinate axes respectively; u (U) rad Is acoustic potential and is related to space-time fluctuation of quantum sound field in the waveguide;<p 2 >and<v 2 >a time average of the square of the instantaneous sound pressure (p) and a time average of the square of the instantaneous velocity (v) of the fluid particles, respectively, over the oscillation period;a p is the equivalent radius of the suspended particles; kappa (kappa) 0 And kappa (kappa) p The compressibility of the air medium and suspended particles, respectively; ρ p Is the density of the suspended particles; c p Sound velocity for suspended particles; f (f) 1 And f 2 Is an acoustic contrast factor and is associated with scattering sound waves by suspended particles. Because equation (1 b) describes the acoustic potential relationship between the wave and the particle in the quantum sound field, it is possible to obtain, in combination with equation (1 a), a positive correlation between the magnitude of the acoustic radiation force and the magnitude of the acoustic pressure amplitude.
For a one-dimensional plane standing wave field simplified by three-dimensional coordinates, the instantaneous sound pressure p and the instantaneous particle velocity v in the sound field are respectively as follows:
p(x,t)＝Pcos(ωt)sin(kx) (2a)
where k=2pi f is the wave number and f is the frequency.
Because the time average of the sine and cosine squares is:
the sound pressure term in the acoustic potential formula (1 b) can be calculated by the time average method of the formula (3) under the position one-dimensional condition by using the formulas (2 a) and (2 b)<p 2 >And velocity term < v 2 >. Thus, the positional one-dimensional acoustic potential
Can be expressed as:
substituting the formula (4) into the formula (1 a) for the position one-dimensional standing wave field, and finishing the sound radiation force
The expression is as follows:
wherein E is ac Is acoustic energy density;
is an improved acoustic contrast factor.
Definition of secondary radiation force:
in addition to each suspended particle being subjected to acoustic radiation forces between antinodes and nodes in a standing wave acoustic field, interactions between different suspended particles also cause the suspended particles themselves to be subjected to secondary radiation forces F' of other suspended particles in the vicinity, expressed as:
in formula 8, θ' is the intersection angle of the line of the centers of the two suspended particles and the propagation direction of the acoustic wave; d' is the distance between the suspended particles; like the angular velocity of the standing wave acoustic field, ω=2pi f=2pi c 0 λ is also the angular velocity of the main flow medium wave. F' consists of a suspended particle velocity term (first term on the right of the equation) and an acoustic pressure term (second term on the right of the equation). Depending on the sign of the actual calculated value of F', the interaction forces appear to be attractive or repulsive.
In the numerical range higher than the critical voltage amplitude, the input voltage amplitude of the loudspeaker is gradually reduced or increased, the relative magnitudes of the acoustic radiation force and the secondary radiation force received by the pneumatic suspended particles are balanced and modulated, the characteristics (such as geometric dimension volume, height, width and the like) of the discrete distributed fluidized particle aggregation are regulated and controlled, and the mixing, crushing, fluidization and transmission processes of the pneumatic suspended particles are improved.
The device and the method have the following action principle: the signal generator 1 inputs an audio signal with specific voltage amplitude and frequency to the speaker 41 through the power amplifier 2, and the small-amplitude sound wave generated by the speaker 41 is amplified by the Helmholtz resonator 42 and then radiated to the waveguide 3 to constitute a non-uniform standing wave sound field. Changing input frequency, testing the maximum sound pressure amplitude in the waveguide tube 3 through the array sound pressure sensor, obtaining a resonance response curve of frequency-maximum sound pressure amplitude, and obtaining the frequency corresponding to the sound pressure amplitude peak value through experiments, namely, each-order resonance frequency of the waveguide tube 3. Under the condition of a certain resonant frequency of the waveguide 3, the relative magnitudes of the acoustic radiation force and the secondary radiation force suffered by the suspended particles are balanced and modulated by changing the amplitude of the input voltage of the loudspeaker 41, and finally the evolution behavior state of the suspended particles in the waveguide 3 is regulated and controlled.
FIGS. 1-2 are schematic diagrams of the apparatus and test schematic diagrams of the present invention. Wherein x is 1 、x 2 、……、x 55 The measuring points in the waveguide tube 3 are used for arranging an array sound pressure sensor, and the array sound pressure sensor is recorded into a computer through data acquisition and test, and the actual resonant frequency of the waveguide tube 3 is obtained after analysis; x-y-z is the coordinate system: o, A, B, C is a feature point on the waveguide; α is an angle of the first fluidized particle aggregate 521 from the radial line OB, and when α changes, it indicates that the first fluidized particle aggregate 521 moves integrally in the waveguide 3; this global movement characteristic is recorded with a camera. The signal generator 1, the power generator 2, and the speaker 41 are connected in an electrical circuit by wires. The circumference of the waveguide 3 is much larger than its inner diameter. The acoustic wavelength is much larger than the inner diameter of the waveguide 3. Above a threshold voltage amplitude of 7V, the dispersed variable volume first and second fluidised particle aggregates 521, 522 together constitute the fluidised particle aggregate 52.
FIG. 4 is a schematic diagram of a collection of striped particles at a lower voltage amplitude during operation of the apparatus of the present invention. When the amplitude of the input voltage to the speaker 41 is lower than the threshold voltage amplitude (e.g., 7V), the pneumatically suspended particles migrate, accumulate, and stack into a plurality of discrete thin film sheet-like clusters 51 of striped particles within the waveguide 3, with the distance between the clusters representing the distance between the two stripes. The dispersed first stripe particle clusters 511, second stripe particle clusters 512, and third stripe particle clusters 513 collectively constitute a stripe particle cluster 51.
The foregoing is only a preferred embodiment of the invention, it being noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the present invention, and such modifications and adaptations are intended to be comprehended within the scope of the invention.
Claims (2)
1. A method for controlling pneumatic suspended particulate matters by sound waves, which is characterized by comprising the following steps: comprises the steps of,
1) The actual resonance frequencies of a plurality of orders of the waveguide tube (3) are tested;
2) The method comprises the steps of taking any first-order resonant frequency of a waveguide tube (3) as the frequency of an audio signal output by a signal generator, changing the voltage amplitude of the audio signal output by the signal generator (1), inputting the audio signal into a loudspeaker (41) after the audio signal is boosted by a power amplifier (2), changing the input voltage amplitude of the loudspeaker (41), generating a non-uniform standing wave sound field in the waveguide tube (3) after a small-amplitude sound wave generated by the loudspeaker (41) is amplified by a Helmholtz resonator (42), and observing and recording the behavior evolution characteristics of pneumatic suspended particles in the non-uniform standing wave sound field in the waveguide tube (3), wherein the behavior evolution characteristics comprise the collision, agglomeration, suspension, sedimentation, removal, mixing, crushing, fluidization and transmission characteristics of the pneumatic suspended particles;
3) Determining a threshold voltage amplitude at which pneumatically-suspended particles transition from a fluidized particle agglomeration (52) state to a striped particle agglomeration (51) state of the striped stack;
4) In the numerical range lower than the critical voltage amplitude, gradually reducing or increasing the input voltage amplitude of the loudspeaker (41), balancing and modulating the relative magnitude of the acoustic radiation force and the secondary radiation force received by the pneumatic suspended particles, regulating and controlling the characteristic of the aggregation of the stripe particles, and improving the collision, agglomeration, sedimentation and removal processes of the pneumatic suspended particles;
in the numerical range higher than the critical voltage amplitude, gradually reducing or increasing the input voltage amplitude of the loudspeaker (41), balancing and modulating the relative magnitude of the acoustic radiation force and the secondary radiation force received by the pneumatic suspended particles, regulating and controlling the characteristic of the discrete distributed fluidized particle aggregation, and improving the mixing, crushing, fluidization and transmission processes of the pneumatic suspended particles;
wherein:
the definition of the acoustic radiation force is:
for the actual suspended small particles equivalent to a spherical structure and with the sphere radius far smaller than the wavelength of sound waves, in a fluid calibrated by a space Cartesian three-dimensional rectangular coordinate system, the sound field generates sound radiation force on the single small particles
The expression is as follows:
in the method, in the process of the invention,
unit vectors corresponding to x, y and z coordinate axes respectively; u (U) rad Is acoustic potential and is related to space-time fluctuation of quantum sound field in the waveguide;<p 2 >and<v 2 >a time average of the squares of the instantaneous sound pressure p and the fluid particle instantaneous velocity v over the oscillation period, respectively; a, a p Is the equivalent radius of the suspended particles; k (K) 0 And k p The compressibility of the air medium and suspended particles, respectively; ρ p Is the density of the suspended particles; c p Sound velocity for suspended particles; f (f) 1 And f 2 Is an acoustic contrast factor, and is related to the scattering sound wave of suspended particles; because equation (1 b) describes the acoustic potential relationship between the wave and the particle in the quantum sound field, it is possible to obtain, in combination with equation (1 a), a positive correlation between the magnitude of the acoustic radiation force and the magnitude of the acoustic pressure amplitude;
for a one-dimensional plane standing wave field simplified by three-dimensional coordinates, the instantaneous sound pressure p and the instantaneous particle velocity v in the sound field are respectively as follows:
p(x,t)＝Pcos(ωt)sin(kx)(2a)
wherein k=2pi f is wave number, f is frequency;
because the time average of the sine and cosine squares is:
under the condition of one dimension of the position, the sound pressure term in the acoustic potential formula (1 b) is calculated by a time average method of the formula (3) by using the formulas (2 a) and (2 b) respectively<p 2 >And velocity term<v 2 >The method comprises the steps of carrying out a first treatment on the surface of the Thus, the positional one-dimensional acoustic potential
The expression is as follows:
substituting the formula (4) into the formula (1 a) for the position one-dimensional standing wave field, and finishing the sound radiation force
The expression is as follows:
wherein E is ac Is acoustic energy density;
is an improved acoustic contrast factor;
definition of secondary radiation force:
in addition to each suspended particle being subjected to acoustic radiation forces between antinodes and nodes in a standing wave acoustic field, interactions between different suspended particles also cause the suspended particles themselves to be subjected to secondary radiation forces F' of other suspended particles in the vicinity, expressed as:
in formula 8, θ' is the intersection angle of the line of the centers of the two suspended particles and the propagation direction of the acoustic wave; d' is the distance between the suspended particles; like the angular velocity of the standing wave acoustic field, ω=2pi f=2pi c 0 λ is also the angular velocity of the main flow medium wave; f' consists of a suspended particle velocity term and an acoustic pressure term; depending on the sign of the actual calculated value of F', the interaction forces appear to be attractive or repulsive.
2. A device for acoustically manipulating pneumatically-suspended particulate matter, for implementing a method for acoustically manipulating pneumatically-suspended particulate matter as recited in claim 1, wherein: the device comprises a signal generator (1) capable of generating sine wave audio, a power amplifier (2), a waveguide tube (3), two identical Helmholtz sound sources (4) arranged at two ends of the waveguide tube (3), and pneumatic suspended particles placed in the waveguide tube (3);
the Helmholtz sound source (4) comprises a loudspeaker (41) and a Helmholtz resonator (42), wherein the Helmholtz resonator (42) is positioned between the port of the waveguide tube (3) and the loudspeaker (41);
the signal generator (1), the power amplifier (2) and the loudspeaker (41) are connected in sequence and form a closed electrical loop;
the signal generator (1) outputs an audio signal with adjustable frequency and voltage amplitude, after the voltage is increased by the power amplifier (2), an alternating current signal is supplied to the loudspeaker (41) of the Helmholtz sound source (4), and a small-amplitude sound wave generated by the loudspeaker (41) is amplified by the Helmholtz resonator (42) to generate a standing wave sound field in the waveguide tube (3);
the frequency of the audio signal output by the signal generator (1) is one of a plurality of orders of resonance frequencies of the waveguide tube (3) obtained through experiments, and the frequency regulation and control range is 1 Hz-20000 Hz; the sound pressure amplitude regulation range of the sound field in the waveguide tube (3) is 0 Pa-1500 Pa;
the input voltage amplitude of the speaker (41) includes a specific threshold voltage amplitude;
when the input voltage amplitude of the loudspeaker (41) is lower than the critical voltage amplitude, the pneumatic suspended particles migrate in the waveguide tube (3) and are gathered into discrete stripe particle gathering groups (51) distributed in a stripe shape;
when the input voltage amplitude of the loudspeaker (41) is higher than the critical voltage amplitude, the pneumatically suspended particles migrate, suspend and aggregate in the waveguide (3) into fluidized particle aggregates (52) mixed with the gaseous medium in the waveguide (3);
the stripe particle aggregation group (51) is in a film sheet shape formed by stacking particles and is perpendicular to the transmission direction of sound waves in the waveguide tube (3);
the fluidized particle agglomerate (52) moves integrally within the waveguide (3) and its outer contour changes dynamically;
and the fluidized particulate collection clusters (52) present a plurality of discrete collection areas within the waveguide (3), the particles moving rapidly within the fluidized particulate collection clusters (52);
the waveguide tube (3) is annular, and the circumference is 978mm;
the critical voltage amplitude is 7V;
the pneumatic suspended particles are cylindrical coke particles generated by rice hull combustion.
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