Linear acceleration acoustic propulsion system and method

Abstract

The invention provides a linear acceleration acoustic propulsion system and method. The linear acceleration acoustic propulsion system comprises a control device and an annular acoustic levitation device. The annular acoustic levitation device is formed by assembling two semi-cylindrical outer walls with transducer bases and a plurality of layers of transducer rings, and each layer of transducer ring comprises a plurality of transducers; the control device is connected with each transducer, the control device is used for outputting a control signal corresponding to each transducer to each transducer, and the control signal is used for controlling the emission sound pressure and phase relation of each layer of transducer ring; and each transducer is used for generating sound waves in response to the received control signal, so that the annular acoustic levitation device generates a Bessel sound field, and linear acceleration of the particulate matter is realized. According to the scheme, efficient and stable linear acceleration and propulsion of particulate matter in an air medium are achieved, and an innovative solution is provided for deep space exploration and small thrust tasks in rarefied atmosphere.

Description

Technical Field

[0001] The present invention relates to the field of aerospace technology, and in particular to a linear acceleration acoustic propulsion system and method. Background Art

[0002] Space propulsion technology is the technology that propels spacecraft to move and maneuver in space. It covers the propulsion systems required for all stages of space missions, from launch to on-orbit operation, attitude control, orbital maneuvers, landing and deep space exploration. Space propulsion technology involves spacecraft propulsion methods and devices, especially new chemical-free propulsion systems, which are suitable for small thrust propulsion of spacecraft such as satellites and probes.

[0003] At present, the main propulsion method for small thrust missions is electric propulsion. Electric propulsion uses electromagnetic energy to accelerate the ejection of the working fluid to obtain a reaction force. The ejection speed can reach 20-50km / s, and the utilization efficiency of the working fluid is high. However, electric propulsion is limited by energy density and power level, and the thrust and thrust-to-weight are relatively small. If the thrust level of chemical propulsion is to be achieved through stacking, the volume and mass of its propulsion system will be much larger than that of the chemical propulsion system, and the engineering difficulty is high and the manufacturing is complex. At the same time, electric propulsion has high requirements on the state and stability of the working fluid, and inert gases such as argon and xenon are often used.

[0004] In practical applications, compared with traditional propulsion technology, acoustic propulsion technology has the advantages of low medium requirements, low manufacturing material requirements, simple device, and controllable device volume and mass. More and more research is focused on achieving small thrust tasks through acoustic propulsion devices. However, acoustic propulsion technology has made some progress in liquid media, but its application in air media still needs further exploration.

[0005] In summary, how to achieve linear acceleration of particulate matter in the air medium to realize effective acoustic propulsion in the air has become a technical problem that needs to be solved urgently. Summary of the invention

[0006] The present invention provides a linear acceleration acoustic propulsion system and method, which are used to solve the defect that the prior art cannot realize linear acceleration of particulate matter in the air medium, and realizes efficient and stable linear acceleration and propulsion of particulate matter in the air medium, providing an innovative solution for deep space exploration and small thrust missions in a thin atmosphere.

[0007] The present invention provides a linear acceleration acoustic propulsion system, comprising: a control device and an annular acoustic suspension device; the annular acoustic suspension device is assembled from two semi-cylindrical outer walls with transducer bases and multiple layers of transducer rings, each layer of transducer rings comprising multiple transducers; the control device is connected to each transducer, the control device is used to output a control signal corresponding to each transducer to each transducer, the control signal is used to control the emission sound pressure and phase relationship of each layer of transducer rings; each transducer is used to generate sound waves in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field, thereby realizing linear acceleration of particulate matter.

[0008] According to a linear acceleration acoustic propulsion system provided by the present invention, the control device includes: a main control board and a drive module; the main control board is connected to the drive module, and the main control board is used to output an intermediate control signal corresponding to each transducer to the drive module; the drive module is connected to each transducer, and the drive module is used to convert the intermediate control signal corresponding to each transducer into a control signal corresponding to each transducer, and output the control signal corresponding to each transducer to each transducer.

[0009] According to a linear acceleration acoustic propulsion system provided by the present invention, the linear acceleration acoustic propulsion system also includes: a DC regulated power supply and a boost circuit; the DC regulated power supply is used to output a DC voltage signal; the input end of the boost circuit is connected to the DC regulated power supply, and the output end of the boost circuit is connected to each transducer, for converting the DC voltage signal into a power supply signal suitable for each transducer.

[0010] The present invention also provides a linear acceleration acoustic propulsion method, which is applied to a linear acceleration acoustic propulsion system, wherein the linear acceleration acoustic propulsion system includes a control device and an annular acoustic suspension device; the annular acoustic suspension device is assembled from two semi-cylindrical outer walls with transducer bases and multiple layers of transducer rings, and each layer of transducer rings includes multiple transducers; the method includes: the control device outputs a control signal corresponding to each transducer to each transducer, and the control signal is used to control the emission sound pressure and phase relationship of each layer of transducer rings; each transducer generates a sound wave in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of particulate matter.

[0011] According to a linear acceleration acoustic propulsion method provided by the present invention, the Bessel sound field is a zero-order Bessel sound field or a first-order Bessel sound field.

[0012] According to a linear acceleration acoustic propulsion method provided by the present invention, the control signal includes a zero-order Bessel sound field control signal; the control device outputs a control signal corresponding to each transducer to each transducer, specifically including: the control device outputs a zero-order Bessel sound field control signal corresponding to each transducer to each transducer; each transducer generates an acoustic wave in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of particulate matter, specifically including: each transducer generates an acoustic wave in response to receiving the zero-order Bessel sound field control signal to achieve acoustic propulsion based on a moving potential well to achieve linear acceleration of particulate matter.

[0013] According to a linear acceleration acoustic propulsion method provided by the present invention, the control signal includes a first-order Bessel sound field control signal; the control device outputs the control signal corresponding to each transducer to each transducer, specifically including: the control device outputs the first-order Bessel sound field control signal corresponding to each transducer to each transducer; each transducer generates a sound wave in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of particulate matter, specifically including: each transducer generates a sound wave in response to receiving the first-order Bessel sound field control signal to achieve acoustic propulsion with decreasing sound intensity layer by layer to achieve linear acceleration of particulate matter.

[0014] According to a linear acceleration acoustic propulsion method provided by the present invention, the method also includes: determining the radius of the transducer ring and the radius of the semi-cylindrical outer wall through single-ring sound field simulation; determining the spacing between adjacent transducer ring layers through multi-ring sound field simulation; based on the design parameters of the annular acoustic suspension device, the two semi-cylindrical outer walls with transducer bases are manufactured through 3D printing technology; the design parameters of the annular acoustic suspension device include the radius of the transducer ring, the radius of the semi-cylindrical outer wall and the spacing between adjacent transducer ring layers.

[0015] According to a linear acceleration acoustic propulsion method provided by the present invention, after the two semi-cylindrical outer walls with transducer bases are manufactured by 3D printing technology based on the radius of the transducer ring, the radius of the semi-cylindrical outer wall and the spacing between adjacent transducer ring layers, the method also includes: assembling the two semi-cylindrical outer walls with transducer bases and multiple transducers manufactured by 3D printing technology to obtain an annular acoustic suspension device to be verified; verifying the linear acceleration process of particulate matter of the annular acoustic suspension device to be verified by computer simulation and acoustic propulsion experiments; and optimizing the design parameters of the annular acoustic suspension device by comparing the verification results of computer simulation and acoustic propulsion experiments.

[0016] According to a linear acceleration acoustic propulsion method provided by the present invention, the control signal is a square wave signal.

[0017] The linear acceleration acoustic propulsion system and method provided by the present invention include: a control device and an annular acoustic suspension device; the annular acoustic suspension device is assembled by two semi-cylindrical outer walls with transducer bases and multiple layers of transducer rings, and each layer of transducer rings includes multiple transducers; the control device is connected to each transducer, and the control device is used to output a control signal corresponding to each transducer to each transducer, and the control signal is used to control the emission sound pressure and phase relationship of each layer of transducer ring; each transducer is used to generate sound waves in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of particulate matter. In the scheme of the present invention, the control device outputs a control signal to each transducer to control the emission sound pressure and phase relationship of each layer of transducer ring, which can achieve precise control of the sound field distribution and the potential well position; each transducer generates a sound wave in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of particulate matter. It can be seen that the solution of the present invention realizes efficient and stable linear acceleration and propulsion of particulate matter in the air medium, and provides an innovative solution for deep space exploration and low-thrust missions in a thin atmosphere. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is one of the structural schematic diagrams of the linear acceleration acoustic propulsion system provided by the present invention.

[0020] Figure 2 This is the second structural schematic diagram of the linear acceleration acoustic propulsion system provided by the present invention.

[0021] Figure 3 It is a schematic flow chart of the linear acceleration acoustic propulsion method provided by the present invention.

[0022] Figure 4 It is a schematic diagram of the acoustic propulsion device based on the mobile potential well provided by the present invention.

[0023] Figure 5 It is a schematic diagram of the suspension of particles by the zero-order Bessel sound field provided by the present invention.

[0024] Figure 6 It is a schematic diagram of the zero-order Bessel acoustic field suspension stability experiment provided by this application.

[0025] Figure 7It is a schematic diagram of the potential well movement experimental process of double-loop control provided by the present invention.

[0026] Figure 8 It is a schematic diagram of the change of the lowest point position of the acoustic field potential well provided by the present invention with the voltage ratio of the second layer ring.

[0027] Fig. 9 It is a schematic diagram of a five-layer first-order Bessel acoustic suspension device provided in this application.

[0028] Fig.10 It is a schematic diagram of the suspension points on the axis of the five-layer first-order Bessel-shaped acoustic suspension device provided by the present invention.

[0029] Fig.11 It is a schematic diagram of particles in the first-order Bessel-shaped acoustic suspension device provided by the present invention recovering to stability after being slightly disturbed.

[0030] Fig.12 It is a schematic diagram of the foam stick provided by the present invention being suspended on an axis. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] It should be noted that the brief description of terms in this application is only for the convenience of understanding the embodiments described below, and is not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their common and usual meanings.

[0033] In addition, the terms "including" and "having" and any variations thereof are intended to cover but not exclude inclusion, for example, a product or device comprising a series of components is not necessarily limited to those components explicitly listed, but may include other components not explicitly listed or inherent to these products or devices. The term "module" as used in this application refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic or combination of hardware and / or software code that can perform the functions associated with the element.

[0034] Space propulsion technology is the technology that propels spacecraft to move and maneuver in space. It covers the propulsion systems required for all stages of space missions, from launch to on-orbit operation, attitude control, orbital maneuvers, landing and deep space exploration. Space propulsion technology involves spacecraft propulsion methods and devices, especially new chemical-free propulsion systems, which are suitable for small thrust propulsion of spacecraft such as satellites and probes.

[0035] At present, the main propulsion method for small thrust missions is electric propulsion. Electric propulsion uses electromagnetic energy to accelerate the ejection of the working fluid to obtain a reaction force. The ejection speed can reach 20-50km / s, and the utilization efficiency of the working fluid is high. However, electric propulsion is limited by energy density and power level, and the thrust and thrust-to-weight are relatively small. If the thrust level of chemical propulsion is to be achieved through stacking, the volume and mass of its propulsion system will be much larger than that of the chemical propulsion system, and the engineering difficulty is high and the manufacturing is complex. At the same time, electric propulsion has high requirements on the state and stability of the working fluid, and inert gases such as argon and xenon are often used.

[0036] The acoustic propulsion device is mainly based on acoustic levitation technology, which generates thrust by manipulating the acceleration of granular materials and ejecting them from the device. Acoustic levitation technology uses the acoustic radiation force of sound waves to provide directional force in space, suspending and manipulating particles, and achieving contactless control. Its basic principle is as follows: objects are subject to acoustic pressure in the sound field. Simple first-order approximation cannot accurately describe the force on the object in the sound field. Therefore, it is necessary to perform a second-order approximation calculation on the sound pressure and medium velocity, and bring them into the Euler equation and continuity equation of the ideal fluid to obtain the acoustic radiation pressure.

[0037] Assuming that the particles do not interfere with the acoustic field and that the particles are rigid, the forces on a rigid sphere in the acoustic field can be calculated. Gor'kov derived a concise expression by assuming that a sphere with a radius much smaller than the wavelength of the acoustic wave is immersed in the acoustic field. From the Gor'kov potential, it can be seen that the particle will be trapped near a low potential energy point in the acoustic field, affected by the trapping force, the magnitude of which is mainly determined by the pressure amplitude gradient and the velocity gradient. The amplitude gradient pushes the particle to the low amplitude region, while the velocity gradient pushes the particle to the high gradient region.

[0038] Acoustic levitation technology is widely used in microgravity environment simulation, material science, biomedical engineering and precision manufacturing. It has achieved the suspension of solid particles, liquid droplets and even small animals. Some researchers have proposed methods for suspending special large objects, including spherical objects and flat objects. However, there are few studies on using sound waves to accelerate objects.

[0039] In practical applications, compared with traditional propulsion technology, acoustic propulsion technology has the advantages of low medium requirements, low manufacturing material requirements, simple device, and controllable device volume and mass. More and more research is focused on achieving small thrust tasks through acoustic propulsion devices. However, acoustic propulsion technology has made some progress in liquid media, but its application in air media still needs further exploration.

[0040] In summary, how to achieve linear acceleration of particulate matter in the air medium to realize effective acoustic propulsion in the air has become a technical problem that needs to be solved urgently.

[0041] The technical solution of the present invention is used to solve the above technical problems. The technical solution of the present application and how the technical solution of the present application solves the above technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. Figure 1-Figure 2 The linear acceleration acoustic propulsion system of the present invention is described.

[0042] Figure 1 FIG. 1 is one of the structural schematic diagrams of the linear acceleration acoustic propulsion system provided by the present invention. Figure 1 As shown, the linear acceleration acoustic propulsion system includes a control device 10 and a ring-shaped acoustic suspension device 20 .

[0043] In this embodiment, the annular acoustic suspension device 20 is assembled by two semi-cylindrical outer walls 201 with transducer bases and multiple layers of transducer rings 202 , and each layer of transducer rings includes multiple transducers 2021 .

[0044] The control device 10 is connected to each transducer 2021 , and is used to output a control signal corresponding to each transducer 2021 to each transducer 2021 , and the control signal is used to control the emission sound pressure and phase relationship of each layer of transducer ring 202 .

[0045] Each transducer 2021 is used to generate sound waves in response to receiving a control signal, so that the annular acoustic suspension device 20 generates a Bessel sound field to achieve linear acceleration of the particulate matter.

[0046] like Figure 1 As shown, the annular acoustic suspension device 20 is an acoustic suspension device in which the transducers 2021 are arranged in an annular shape and the emitting surface is directed toward the center of the annular shape. For the annular acoustic suspension device in an open sound field, in order to form a standing wave, its diameter is required to be ,in is the wavelength of sound in the medium. The initial phases of the transducers 2021 are arranged linearly, and the phase difference of one circle of the transducer ring 202 is At this time, the relationship between the sound pressure field in the middle part and the distance to the axis is approximately a Bessel function, so it is called a Bessel-shaped sound field.

[0047] In this embodiment, the control device 10 outputs a control signal corresponding to each transducer 2021 to each transducer 2021. The control signal can control the emission sound pressure and phase relationship of each layer of transducer ring 202, and can achieve precise control of the Bessel-shaped sound field, thereby achieving linear acceleration of particulate matter. In this embodiment, by adjusting the emission sound pressure and phase relationship of each layer of transducer ring 202, a flexible propulsion control method is achieved, which can adapt to different mission requirements and environmental conditions.

[0048] In this embodiment, there is no specific limitation on the form of the control signal. As an example, the control signal may be a square wave signal, a sine wave signal, a triangle wave signal, a sawtooth wave signal, a pulse width modulation signal (PWM), a custom waveform signal, etc.

[0049] In one implementation, the control signal is a square wave signal, and the control signal is used to control the transmitted sound pressure and phase relationship of each layer of the transducer ring 202 .

[0050] Specifically, the present invention does not specifically limit the manner in which the control device 10 controls the emission sound pressure of each layer of the transducer ring 202. In one example, the control device 10 can control the emission sound pressure of each layer of the transducer ring 202 by controlling the duty cycle of the square wave signal. Specifically, the control device 10 controls the emission voltage of each layer of the transducer ring 202 by adjusting the duty cycle of the square wave signal. For a pulse width modulated (PWM) square wave signal, the control device 10 can change the average voltage output by adjusting the duty cycle of the square wave signal, thereby controlling the emission sound pressure of each layer of the transducer ring 202. In another example, the control device 10 can control the emission sound pressure of each layer of the transducer ring 202 by controlling the peak-to-peak value of the square wave signal. Specifically, the control device 10 controls the emission voltage of each layer of the transducer ring 202 by adjusting the peak-to-peak value of the square wave signal. In another example, the emission sound pressure of each layer of the transducer ring 202 is controlled by controlling the manner in which the square wave signal is amplified. Specifically, the control device 10 adjusts the transmission voltage of each layer of transducer ring 202 by signal amplification. An amplifier is added to the signal chain, and the amplitude of the square wave signal output to the transducer is controlled by adjusting the gain of the amplifier.

[0051] Specifically, the present invention does not specifically limit the manner in which the control device 10 controls the phase relationship of each layer of transducer rings 202. In one example, the control device 10 can control the phase relationship of each layer of transducer rings 202 by controlling the time delay of the square wave signal. Specifically, by introducing a precise time delay between different square wave signals, the phase relationship of each layer of transducer rings 202 can be adjusted. This can be achieved by a digital signal processor or a dedicated phase delay circuit. In another example, the control device 10 synchronously generates multiple square wave signals and assigns a different initial phase or time delay to each signal to control the phase relationship of each layer of transducer rings 202.

[0052] Exemplarily, the above-mentioned Bessel sound field is a zero-order Bessel sound field or a first-order Bessel sound field. In this embodiment, by controlling the phase relationship of each layer of transducer ring 202, the annular acoustic suspension device 20 is controlled to generate a zero-order Bessel sound field or a first-order Bessel sound field. Specifically, let , that is, the phase difference of one circle of the transducer ring 202 is , at this time, the radius of the cylinder The point is a low potential energy point, which can capture particulate matter on the axis. At this time, the annular acoustic suspension device 20 generates a first-order Bessel sound field. Correspondingly, let At this time, the central axis of the annular acoustic suspension device 20 is a high potential energy area, and the generated potential well presents a concentric ring shape around the central axis. At this time, the annular acoustic suspension device 20 generates a zero-order Bessel sound field.

[0053] It should be noted that both the zero-order Bessel-shaped sound field and the first-order Bessel-shaped sound field can generate capture force, but their characteristics in the sound field and the mode of action of the capture force are different. Specifically, the sound field generated by the zero-order Bessel-shaped sound field forms a deep potential well at the center of the ring, and this sound field mode is particularly suitable for capturing and suspending particles. Due to its axial symmetry, the sound pressure of the zero-order Bessel-shaped sound field at the center of the ring is zero, while the sound pressure is the largest on the axis of the ring, thereby generating a stable capture area at the center of the ring. This capture force mainly comes from the sound pressure gradient, which pushes the particles to the low sound pressure area, that is, the center of the ring. Correspondingly, the sound field generated by the first-order Bessel-shaped sound field forms an annular potential well on the axis of the ring, and this sound field mode is suitable for guiding and moving particles near the axis. The capture force of the first-order Bessel-shaped sound field includes not only the force that pushes the particles to the low sound pressure area, but also the force generated by the velocity gradient, which pushes the particles to the high velocity gradient area. This sound field mode can be used to manipulate particles to move in a specific direction, such as along the axis of the ring.

[0054] In general, the capture force generated by the zero-order Bessel-shaped acoustic field is mainly at the center of the ring, which is suitable for suspending and fixing particles, while the capture force generated by the first-order Bessel-shaped acoustic field is distributed along the axis of the ring, which is suitable for guiding and moving particles. These two acoustic field modes have important applications in acoustic levitation and acoustic manipulation technologies.

[0055] As an example, in one implementation, the control signal includes a zero-order Bessel sound field control signal; the control device 10 is specifically configured to: output the zero-order Bessel sound field control signal corresponding to each transducer 2021 to each transducer 2021 .

[0056] Each transducer 2021 is specifically used to generate sound waves in response to receiving a zero-order Bessel sound field control signal, and realize acoustic propulsion based on a moving potential well, so as to achieve linear acceleration of particulate matter.

[0057] In practical applications, by adjusting the magnitude relationship of the transmitted sound pressures between the transducer rings 202, the potential well can be smoothly moved between the transducer rings 202. Specifically, the transmitted sound pressure of each layer of transducer rings 202 is adjusted in sequence, for example, the transmitted sound pressure of the a ring is linearly reduced from 100% to 0, and the transmitted sound pressure of the b ring is linearly increased from 0 to 100%, so that the potential well is smoothly moved from the center of the a ring to the center of the b ring.

[0058] In this embodiment, the moving potential well method is used to achieve efficient acceleration and propulsion of particles, thereby improving the efficiency of the propulsion system.

[0059] As an example, in one implementation, the control signal includes a first-order Bessel sound field control signal; the control device 10 is specifically configured to: output the first-order Bessel sound field control signal corresponding to each transducer 2021 to each transducer 2021 .

[0060] Each of the above transducers 2021 is specifically used for: In response to receiving a first-order Bessel sound field control signal, a sound wave is generated to achieve sound propulsion with a sound intensity decreasing layer by layer, so as to achieve linear acceleration of the particle matter.

[0061] In practical applications, the particles are constrained on the central axis of the device through a first-order Bessel-shaped sound field, and then the emission sound pressure of each transducer ring is reduced layer by layer to create a Gor'kov potential difference, thereby promoting the movement of the particle material. Specifically, the sound pressure of the transducer ring 202 is set to decrease by 10% layer by layer, for example, starting from the outermost layer, the sound pressure of each layer of transducer ring is reduced in sequence, so that the Gor'kov potential gradually decreases in the axial direction, forming a continuous potential difference, and promoting the particles to move along the axial direction.

[0062] In practical applications, software can be used to simulate the sound field to determine the ratio of the sound intensity decreasing layer by layer, and the sound pressure output by the transducer ring decreases by 10% layer by layer. The greater the degree of sound intensity reduction, the greater the gradient of the Gor'kov potential in the axial direction, and the greater the acceleration that can be provided. However, if the difference in sound intensity between adjacent rings is too large, it will affect the smoothness of the central energy channel. At the same time, too low sound intensity will also make the device's restraint on particulate matter unstable. Detect the movement speed and stability of the particulate matter, whether it can move stably between the rings, and determine the ratio of the sound intensity decreasing layer by layer.

[0063] In this embodiment, the method of decreasing the sound intensity layer by layer is used to achieve efficient acceleration and propulsion of particles, thereby improving the efficiency of the propulsion system.

[0064] In the scheme of this embodiment, the control device 10 outputs a control signal to each transducer 2021 to control the emission sound pressure and phase relationship of each layer of transducer ring 202, so as to achieve precise control of the sound field distribution and the potential well position; each transducer 2021 generates a sound wave in response to receiving the control signal, so that the annular acoustic suspension device 20 generates a Bessel sound field to achieve linear acceleration of the particulate matter. It can be seen that the scheme of this embodiment achieves efficient and stable linear acceleration and propulsion of particulate matter in the air medium, and provides an innovative solution for deep space exploration and small thrust missions in a rarefied atmosphere.

[0065] Furthermore, in another embodiment, Figure 2 FIG. 2 is a second structural diagram of the linear acceleration acoustic propulsion system provided by the present invention. Figure 2 As shown, the control device 10 comprises: a main control board 101 and a driving module 102 .

[0066] The main control board 101 is connected to the driving module 102 , and the main control board 101 is used to output an intermediate control signal corresponding to each transducer 2021 to the driving module 102 .

[0067] The driving module 102 is connected to each transducer 2021 , and is used to convert the intermediate control signal corresponding to each transducer 2021 into a control signal 2021 corresponding to each transducer, and output the control signal corresponding to each transducer 2021 to each transducer 2021 .

[0068] On the one hand, the main control board 101 can generate accurate intermediate control signals corresponding to each transducer 2021, including specific frequencies, phases, and amplitudes, and the driver module 102 is responsible for amplifying these intermediate control signals to a sufficient power level to drive the transducer 2021. On the other hand, the main control board 101 can be programmed to generate a variety of complex intermediate control signals, and the driver module 102 can adapt to the changes in these signals, providing a high degree of flexibility to meet different sound field control requirements. On the other hand, the driver module 102 can isolate and protect the main control board 101 from high voltages and high currents, improving the reliability and durability of the system.

[0069] In this embodiment, the combination of the main control board 101 and the driving module 102 provides a powerful control platform for the linear acceleration acoustic propulsion system, which can achieve accurate, flexible and efficient sound field control and meet various complex sound field designs and application requirements.

[0070] In addition, in a possible implementation, the above-mentioned linear acceleration acoustic propulsion system further includes: a DC regulated power supply and a boost circuit.

[0071] DC regulated power supply, used to output DC voltage signal.

[0072] The input end of the boost circuit is connected to a DC regulated power supply, and the output end of the boost circuit is connected to each transducer 2021, for converting a DC voltage signal into a power supply signal suitable for each transducer.

[0073] It is understandable that the DC regulated power supply can ensure the provision of a stable voltage source, reduce the impact of voltage fluctuations on device performance, and ensure the reliability and stability of the operation of the transducer 2021. The boost circuit can boost the DC voltage signal output by the DC regulated power supply to a higher voltage level required by the transducer 2021 to meet the need for the transducer 2021 to generate sufficient sound pressure. This power supply method provides flexibility, allowing system designers to adjust the boost circuit according to the specific requirements of the transducer 2021 to achieve optimal performance.

[0074] In this embodiment, the combination of the DC regulated power supply and the boost circuit provides a stable, efficient, flexible and reliable power supply solution for the annular acoustic suspension device 20 , which helps to achieve the best performance of the annular acoustic suspension device 20 .

[0075] In combination with the above description, the annular acoustic suspension device 20 is assembled by two semi-cylindrical outer walls 201 with transducer bases and a multi-layer transducer ring 202, and each layer of transducer ring includes a plurality of transducers 2021. In practice, the semi-cylindrical outer walls 201 with transducer bases can be spliced ​​to form a whole cylindrical structure, which is more suitable for installing transducers and can improve the efficiency of assembling the annular acoustic suspension device 20.

[0076] In practical applications, two semi-cylindrical outer walls 201 with transducer bases need to be prepared in advance. As an example, in a possible implementation, preparing the annular acoustic suspension device 20 includes the following steps.

[0077] Step 1: Determine the radius of the transducer ring and the radius of the semi-cylindrical outer wall through single-ring sound field simulation.

[0078] As an example, Comsol Multiphysics software is used to simulate the sound field generated by a single transducer ring in detail. Specifically, a simulation model is created to simulate a single transducer ring in a ring-shaped acoustic suspension device and the air environment around it. The transducer diameter is set to 10 mm, the frequency is 40 kHz, the radius of the annular transducer emission cylinder is 13 mm, and the outer wall radius is set to 20 mm and the outer wall thickness is 3 mm in the simulation model to ensure that the sound waves emitted by the transducer can be reflected inside the outer wall and form a stable sound field. Run the simulation calculation to analyze the sound field distribution generated by the transducer ring under the set frequency and boundary conditions, focusing on the sound pressure distribution and potential well position in the central area. Generate a spatial distribution diagram of the Gor'kov potential, determine the position and intensity of the potential well formed in the center of the ring, ensure that the sound field can produce a stable suspension area in the center of the ring, and adjust the parameter combination of the transducer ring radius and the outer wall radius until the ideal sound field distribution is obtained to ensure that the single ring can produce a stable Bessel potential well in the center of the ring, and obtain the radius of the transducer ring and the radius of the semi-cylindrical outer wall. Among them, the ideal sound field distribution has the following characteristics: the potential energy along the axis of the cylinder is continuous; the potential energy at the particle capture point is strong and the restraint force is large.

[0079] Step 2: Determine the spacing between adjacent transducer ring layers through multi-ring sound field simulation.

[0080] Combined with the above description, multiple layers of transducer rings are arranged along the axial direction of the annular acoustic suspension device 20, and the distance between each layer will affect the ability to capture particles. In the multi-ring sound field simulation process, by changing the spacing between adjacent transducer ring layers, the spatial distribution of potential energy received by the particles is calculated, and the inter-layer distance corresponding to the potential energy distribution with the strongest potential energy and the most continuous potential energy distribution along the axis is found, and the ideal spacing between adjacent transducer ring layers is determined.

[0081] Among them, multi-ring sound field simulation refers to the detailed simulation of the sound field generated by the superposition of multiple transducer rings. Specifically, based on the optimal parameters determined by the single-ring simulation, the combination of multiple transducer rings is simulated, the radius of each layer of transducer ring is set to 13mm, the outer wall radius is set to 20mm, and a layer of transducer ring is placed at a fixed interval of 13mm along the axial direction. By changing the ring spacing, the corresponding potential energy distribution is simulated, the sound field distribution between each layer of rings and the spatial distribution of Gor'kov potential are analyzed, and the potential well connection between each layer of rings is focused on to ensure the formation of a continuous and uniform energy channel, and then the ring spacing corresponding to the potential energy distribution with strong continuity is selected as the spacing between adjacent transducer ring layers.

[0082] Step 3: Based on the design parameters of the annular acoustic suspension device 20, two semi-cylindrical outer walls 201 with transducer bases are manufactured by 3D printing technology; the design parameters of the annular acoustic suspension device 20 include the radius of the transducer ring, the radius of the semi-cylindrical outer wall, and the spacing between adjacent transducer ring layers.

[0083] Step 4: Use 3D printing technology to manufacture the two semi-cylindrical outer walls 201 with transducer bases and multiple transducers 2021, and assemble them to obtain the annular acoustic suspension device 20 to be verified.

[0084] For example, a semi-cylindrical outer wall with a transducer base is made using 3D printing technology. Each transducer base has a diameter of 10mm and a depth of 5mm, which is used to stably install the transducer. Ultrasonic transducers are selected, and a circle of transducer rings are placed at fixed intervals along the axial direction inside the cylindrical outer wall, with a total of 5 layers, and each layer of transducer rings contains 8 transducers evenly distributed. Furthermore, a power supply system is designed, using a 7.5V DC regulated power supply, and the voltage is increased to 20V through an adjustable boost module, connected to the motor drive module, and then the Arduino Nano main control board generates a 40kHz square wave signal to control the emission sound pressure of each layer of transducers, so as to achieve precise control of the sound field. The device design ensures the formation of a stable Bessel-shaped sound field by adjusting the ring structure and transducer arrangement.

[0085] Step 5: Verify the linear acceleration process of the particle material of the annular acoustic suspension device to be verified by computer simulation and acoustic propulsion experiment respectively; compare the verification results of computer simulation and acoustic propulsion experiment, and optimize the design parameters of the annular acoustic suspension device 20.

[0086] Specifically, the acoustic propulsion process of the moving potential well is verified using computer simulation and experiments to ensure that the velocity and acceleration of the particle are almost equal to the velocity and acceleration of the potential well, and the design parameters of the annular acoustic levitation device 20 are optimized to achieve a stable moving potential well.

[0087] Specifically, Comsol software is used to simulate the acoustic propulsion process with gradually decreasing sound intensity to verify its feasibility, and the influence of decreasing sound pressure on particle stability and movement speed is verified through experiments to optimize the design parameters of the annular acoustic suspension device 20.

[0088] In this embodiment, the design parameters of the annular acoustic suspension device are determined by single-ring sound field simulation and multi-ring sound field simulation, and the two semi-cylindrical outer walls with transducer bases are manufactured by 3D printing technology. Two semi-cylindrical outer walls with transducer bases and multiple transducers are manufactured by 3D printing technology, and the annular acoustic suspension device to be verified is assembled. The linear acceleration process of the particulate matter of the annular acoustic suspension device to be verified is verified by computer simulation and acoustic propulsion experiments respectively; the verification results of computer simulation and acoustic propulsion experiments are compared to optimize the design parameters of the annular acoustic suspension device. In this embodiment, the feasibility and effectiveness of the technical solution are ensured through detailed simulation and experimental verification, and reliable data support and theoretical basis are provided. By optimizing the design parameters of the annular acoustic suspension device, the accuracy and reliability of the linear acceleration acoustic propulsion are improved.

[0089] The linear acceleration acoustic propulsion system provided in this embodiment includes: a control device and an annular acoustic suspension device; the annular acoustic suspension device is assembled by two semi-cylindrical outer walls with transducer bases and multiple layers of transducer rings, and each layer of transducer rings includes multiple transducers; the control device is connected to each transducer, and the control device is used to output a control signal corresponding to each transducer to each transducer, and the control signal is used to control the emission sound pressure and phase relationship of each layer of transducer ring; each transducer is used to generate sound waves in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of particulate matter. In this embodiment, the control device outputs a control signal to each transducer to control the emission sound pressure and phase relationship of each layer of transducer ring, which can achieve precise control of the sound field distribution and the potential well position; each transducer generates a sound wave in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of particulate matter. It can be seen that the solution of this embodiment realizes efficient and stable linear acceleration and propulsion of particulate matter in the air medium, and provides an innovative solution for deep space exploration and low-thrust missions in a thin atmosphere.

[0090] The linear acceleration acoustic propulsion method provided by the present invention is described below. The linear acceleration acoustic propulsion method described below and the linear acceleration acoustic propulsion system described above can be referred to each other.

[0091] Specifically, the linear acceleration acoustic propulsion method is applied to the linear acceleration acoustic propulsion system, combined with Figure 1The linear acceleration acoustic propulsion system includes a control device 10 and an annular acoustic suspension device 20; the annular acoustic suspension device 20 is assembled by two semi-cylindrical outer walls 201 with transducer bases and a multi-layer transducer ring 202, and each layer of the transducer ring includes a plurality of transducers 2021.

[0092] Figure 3 FIG. 1 is a flow chart of the linear acceleration acoustic propulsion method provided by the present invention, such as Figure 3 As shown, the linear acceleration acoustic propulsion method includes step 301 and step 302.

[0093] Step 301: The control device outputs a control signal corresponding to each transducer to each transducer, where the control signal is used to control the emission sound pressure and phase relationship of each layer of transducer ring.

[0094] Step 302: Each transducer generates a sound wave in response to receiving a control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of the particulate matter.

[0095] Combination Figure 1 The annular acoustic suspension device 20 is an acoustic suspension device in which the transducers 2021 are arranged in an annular shape and the emitting surface is directed toward the center of the annular shape. For the annular acoustic suspension device in an open sound field, in order to form a standing wave, the diameter is required to be ,in is the wavelength of sound in the medium. The initial phases of the transducers 2021 are arranged linearly, and the phase difference of one circle of the transducer ring 202 is At this time, the relationship between the sound pressure field in the middle part and the distance to the axis is approximately a Bessel function, so it is called a Bessel-shaped sound field.

[0096] In this embodiment, the control device 10 outputs a control signal corresponding to each transducer 2021 to each transducer 2021. The control signal can control the emission sound pressure and phase relationship of each layer of transducer ring 202, and can achieve precise control of the Bessel-shaped sound field, thereby achieving linear acceleration of particulate matter. In this embodiment, by adjusting the emission sound pressure and phase relationship of each layer of transducer ring 202, a flexible propulsion control method is achieved, which can adapt to different mission requirements and environmental conditions.

[0097] In this embodiment, there is no specific limitation on the form of the control signal. As an example, the control signal may be a square wave signal, a sine wave signal, a triangle wave signal, a sawtooth wave signal, a pulse width modulation signal (PWM), a custom waveform signal, etc.

[0098] In one implementation, the control signal is a square wave signal, and the control signal is used to control the transmitted sound pressure and phase relationship of each layer of the transducer ring 202 .

[0099] Specifically, the present invention does not specifically limit the manner in which the control device 10 controls the emission sound pressure of each layer of the transducer ring 202. In one example, the control device 10 can control the emission sound pressure of each layer of the transducer ring 202 by controlling the duty cycle of the square wave signal. Specifically, the control device 10 controls the emission voltage of each layer of the transducer ring 202 by adjusting the duty cycle of the square wave signal. For a pulse width modulated (PWM) square wave signal, the control device 10 can change the average voltage output by adjusting the duty cycle of the square wave signal, thereby controlling the emission sound pressure of each layer of the transducer ring 202. In another example, the control device 10 can control the emission sound pressure of each layer of the transducer ring 202 by controlling the peak-to-peak value of the square wave signal. Specifically, the control device 10 controls the emission voltage of each layer of the transducer ring 202 by adjusting the peak-to-peak value of the square wave signal. In another example, the emission sound pressure of each layer of the transducer ring 202 is controlled by controlling the manner in which the square wave signal is amplified. Specifically, the control device 10 adjusts the transmission voltage of each layer of transducer ring 202 by signal amplification. An amplifier is added to the signal chain, and the amplitude of the square wave signal output to the transducer is controlled by adjusting the gain of the amplifier.

[0100] Specifically, the present invention does not specifically limit the manner in which the control device 10 controls the phase relationship of each layer of transducer rings 202. In one example, the control device 10 can control the phase relationship of each layer of transducer rings 202 by controlling the time delay of the square wave signal. Specifically, by introducing a precise time delay between different square wave signals, the phase relationship of each layer of transducer rings 202 can be adjusted. This can be achieved by a digital signal processor or a dedicated phase delay circuit. In another example, the control device 10 synchronously generates multiple square wave signals and assigns a different initial phase or time delay to each signal to control the phase relationship of each layer of transducer rings 202.

[0101] Exemplarily, the above-mentioned Bessel sound field is a zero-order Bessel sound field or a first-order Bessel sound field. In this embodiment, by controlling the phase relationship of each layer of transducer ring 202, the annular acoustic suspension device 20 is controlled to generate a zero-order Bessel sound field or a first-order Bessel sound field. Specifically, let , that is, the phase difference of one circle of the transducer ring 202 is , at this time, the radius of the cylinder The point is a low potential energy point, which can capture particulate matter on the axis. At this time, the annular acoustic suspension device 20 generates a first-order Bessel sound field. Correspondingly, let At this time, the central axis of the annular acoustic suspension device 20 is a high potential energy area, and the generated potential well presents a concentric ring shape around the central axis. At this time, the annular acoustic suspension device 20 generates a zero-order Bessel sound field.

[0102] It should be noted that both the zero-order Bessel-shaped sound field and the first-order Bessel-shaped sound field can generate capture force, but their characteristics in the sound field and the mode of action of the capture force are different. Specifically, the sound field generated by the zero-order Bessel-shaped sound field forms a deep potential well at the center of the ring, and this sound field mode is particularly suitable for capturing and suspending particles. Due to its axial symmetry, the sound pressure of the zero-order Bessel-shaped sound field at the center of the ring is zero, while the sound pressure is the largest on the axis of the ring, thereby generating a stable capture area at the center of the ring. This capture force mainly comes from the sound pressure gradient, which pushes the particles to the low sound pressure area, that is, the center of the ring. Correspondingly, the sound field generated by the first-order Bessel-shaped sound field forms an annular potential well on the axis of the ring, and this sound field mode is suitable for guiding and moving particles near the axis. The capture force of the first-order Bessel-shaped sound field includes not only the force that pushes the particles to the low sound pressure area, but also the force generated by the velocity gradient, which pushes the particles to the high velocity gradient area. This sound field mode can be used to manipulate particles to move in a specific direction, such as along the axis of the ring.

[0103] In general, the capture force generated by the zero-order Bessel-shaped acoustic field is mainly at the center of the ring, which is suitable for suspending and fixing particles, while the capture force generated by the first-order Bessel-shaped acoustic field is distributed along the axis of the ring, which is suitable for guiding and moving particles. These two acoustic field modes have important applications in acoustic levitation and acoustic manipulation technologies.

[0104] As an example, in one embodiment, the control signal includes a zero-order Bessel sound field control signal; the step 301 specifically includes: the control module 10 outputs a zero-order Bessel sound field control signal corresponding to each transducer 2021 to each transducer 2021, and the zero-order Bessel sound field control signal is used to control the emission sound pressure and phase relationship of each layer of transducer ring.

[0105] The above step 301 specifically includes: each transducer 2021 generates a sound wave in response to receiving a zero-order Bessel sound field control signal, and implements acoustic propulsion based on a moving potential well, so as to achieve linear acceleration of the particulate matter.

[0106] In practical applications, by adjusting the magnitude relationship of the transmitted sound pressures between the transducer rings 202, the potential well can be smoothly moved between the transducer rings 202. Specifically, the transmitted sound pressure of each layer of transducer rings 202 is adjusted in sequence, for example, the transmitted sound pressure of the a ring is linearly reduced from 100% to 0, and the transmitted sound pressure of the b ring is linearly increased from 0 to 100%, so that the potential well is smoothly moved from the center of the a ring to the center of the b ring.

[0107] In this embodiment, the moving potential well method is used to achieve efficient acceleration and propulsion of particles, thereby improving the efficiency of the propulsion system.

[0108] As an example, in one embodiment, the control signal includes a first-order Bessel sound field control signal; the step 301 specifically includes: the control device 10 outputs a first-order Bessel sound field control signal corresponding to each transducer 2021 to each transducer 2021, and the first-order Bessel sound field control signal is used to control the emission sound pressure and phase relationship of each layer of transducer ring.

[0109] The above step 301 specifically includes: each transducer 2021 generates a sound wave in response to receiving a first-order Bessel sound field control signal, so as to achieve acoustic propulsion with a sound intensity decreasing layer by layer, so as to achieve linear acceleration of the particulate matter.

[0110] In practical applications, the particles are constrained on the central axis of the device through a first-order Bessel-shaped sound field, and then the emission sound pressure of each transducer ring is reduced layer by layer to create a Gor'kov potential difference, thereby promoting the movement of the particle material. Specifically, the sound pressure of the transducer ring 202 is set to decrease by 10% layer by layer, for example, starting from the outermost layer, the sound pressure of each layer of transducer ring is reduced in sequence, so that the Gor'kov potential gradually decreases in the axial direction, forming a continuous potential difference, and promoting the particles to move along the axial direction.

[0111] In practical applications, software can be used to simulate the sound field to determine the ratio of the sound intensity decreasing layer by layer, and the sound pressure output by the transducer ring decreases by 10% layer by layer. The greater the degree of sound intensity reduction, the greater the gradient of the Gor'kov potential in the axial direction, and the greater the acceleration that can be provided. However, if the difference in sound intensity between adjacent rings is too large, it will affect the smoothness of the central energy channel. At the same time, too low sound intensity will also make the device's restraint on particulate matter unstable. Detect the movement speed and stability of the particulate matter, whether it can move stably between the rings, and determine the ratio of the sound intensity decreasing layer by layer.

[0112] In this embodiment, the method of decreasing the sound intensity layer by layer is used to achieve efficient acceleration and propulsion of particles, thereby improving the efficiency of the propulsion system.

[0113] In the scheme of this embodiment, the control device 10 outputs a control signal to each transducer 2021 to control the emission sound pressure and phase relationship of each layer of transducer ring 202, so as to achieve precise control of the sound field distribution and the potential well position; each transducer 2021 generates a sound wave in response to receiving the control signal, so that the annular acoustic suspension device 20 generates a Bessel sound field to achieve linear acceleration of the particulate matter. It can be seen that the scheme of this embodiment achieves efficient and stable linear acceleration and propulsion of particulate matter in the air medium, and provides an innovative solution for deep space exploration and small thrust missions in a rarefied atmosphere.

[0114] In addition, in a possible embodiment, in combination Figure 2The control device 10 includes: a main control board 101 and a driving module 102. The step 301 includes: the main control board 101 outputs an intermediate control signal corresponding to each transducer 2021 to the driving module 102; the driving module 102 converts the intermediate control signal corresponding to each transducer 2021 into a control signal 2021 corresponding to each transducer, and outputs the control signal corresponding to each transducer 2021 to each transducer 2021.

[0115] On the one hand, the main control board 101 can generate accurate intermediate control signals corresponding to each transducer 2021, including specific frequencies, phases, and amplitudes, and the driver module 102 is responsible for amplifying these intermediate control signals to a sufficient power level to drive the transducer 2021. On the other hand, the main control board 101 can be programmed to generate a variety of complex intermediate control signals, and the driver module 102 can adapt to the changes in these signals, providing a high degree of flexibility to meet different sound field control requirements. On the other hand, the driver module 102 can isolate and protect the main control board 101 from high voltages and high currents, improving the reliability and durability of the system.

[0116] In this embodiment, the combination of the main control board 101 and the driving module 102 provides a powerful control platform for the linear acceleration acoustic propulsion system, which can achieve accurate, flexible and efficient sound field control and meet various complex sound field designs and application requirements.

[0117] In addition, in a possible implementation, the above-mentioned linear acceleration acoustic propulsion system also includes: a DC regulated power supply and a boost circuit, and the above-mentioned linear acceleration acoustic propulsion method also includes: the DC regulated power supply outputs a DC voltage signal; the boost circuit converts the DC voltage signal into a power supply signal suitable for each transducer.

[0118] It is understandable that the DC regulated power supply can ensure the provision of a stable voltage source, reduce the impact of voltage fluctuations on device performance, and ensure the reliability and stability of the operation of the transducer 2021. The boost circuit can boost the DC voltage signal output by the DC regulated power supply to a higher voltage level required by the transducer 2021 to meet the need for the transducer 2021 to generate sufficient sound pressure. This power supply method provides flexibility, allowing system designers to adjust the boost circuit according to the specific requirements of the transducer 2021 to achieve optimal performance.

[0119] In this embodiment, the combination of the DC regulated power supply and the boost circuit provides a stable, efficient, flexible and reliable power supply solution for the annular acoustic suspension device 20 , which helps to achieve the best performance of the annular acoustic suspension device 20 .

[0120] In combination with the above description, the annular acoustic suspension device 20 is assembled by two semi-cylindrical outer walls 201 with transducer bases and a multi-layer transducer ring 202, and each layer of transducer ring includes a plurality of transducers 2021. In practice, the semi-cylindrical outer walls 201 with transducer bases can be spliced ​​to form a whole cylindrical structure, which is more suitable for installing transducers and can improve the efficiency of assembling the annular acoustic suspension device 20.

[0121] In practical applications, two semi-cylindrical outer walls 201 with transducer bases need to be prepared in advance. As an example, in a possible implementation, preparing the annular acoustic suspension device 20 includes the following steps.

[0122] Step 1: Determine the radius of the transducer ring and the radius of the semi-cylindrical outer wall through single-ring sound field simulation.

[0123] As an example, Comsol Multiphysics software is used to simulate the sound field generated by a single transducer ring in detail. Specifically, a simulation model is created to simulate a single transducer ring in a ring-shaped acoustic suspension device and the air environment around it. The transducer diameter is set to 10 mm, the frequency is 40 kHz, the radius of the annular transducer emission cylinder is 13 mm, and the outer wall radius is set to 20 mm and the outer wall thickness is 3 mm in the simulation model to ensure that the sound waves emitted by the transducer can be reflected inside the outer wall and form a stable sound field. Run the simulation calculation to analyze the sound field distribution generated by the transducer ring under the set frequency and boundary conditions, focusing on the sound pressure distribution and potential well position in the central area. Generate a spatial distribution diagram of the Gor'kov potential, determine the position and intensity of the potential well formed in the center of the ring, ensure that the sound field can produce a stable suspension area in the center of the ring, and adjust the parameter combination of the transducer ring radius and the outer wall radius until the ideal sound field distribution is obtained to ensure that the single ring can produce a stable Bessel potential well in the center of the ring, and obtain the radius of the transducer ring and the radius of the semi-cylindrical outer wall. Among them, the ideal sound field distribution has the following characteristics: the potential energy along the axis of the cylinder is continuous; the potential energy at the particle capture point is strong and the restraint force is large.

[0124] Step 2: Determine the spacing between adjacent transducer ring layers through multi-ring sound field simulation.

[0125] Combined with the above description, multiple layers of transducer rings are arranged along the axial direction of the annular acoustic suspension device 20, and the distance between each layer will affect the ability to capture particles. In the multi-ring sound field simulation process, by changing the spacing between adjacent transducer ring layers, the spatial distribution of potential energy received by the particles is calculated, and the inter-layer distance corresponding to the potential energy distribution with the strongest potential energy and the most continuous potential energy distribution along the axis is found, and the ideal spacing between adjacent transducer ring layers is determined.

[0126] Among them, multi-ring sound field simulation refers to the detailed simulation of the sound field generated by the superposition of multiple transducer rings. Specifically, based on the optimal parameters determined by the single-ring simulation, the combination of multiple transducer rings is simulated, the radius of each layer of transducer ring is set to 13mm, the outer wall radius is set to 20mm, and a layer of transducer ring is placed at a fixed interval of 13mm along the axial direction. By changing the ring spacing, the corresponding potential energy distribution is simulated, the sound field distribution between each layer of rings and the spatial distribution of Gor'kov potential are analyzed, and the potential well connection between each layer of rings is focused on to ensure the formation of a continuous and uniform energy channel, and then the ring spacing corresponding to the potential energy distribution with strong continuity is selected as the spacing between adjacent transducer ring layers.

[0127] Step 3: Based on the design parameters of the annular acoustic suspension device 20, two semi-cylindrical outer walls 201 with transducer bases are manufactured by 3D printing technology; the design parameters of the annular acoustic suspension device 20 include the radius of the transducer ring, the radius of the semi-cylindrical outer wall, and the spacing between adjacent transducer ring layers.

[0128] Step 4: Use 3D printing technology to manufacture the two semi-cylindrical outer walls 201 with transducer bases and multiple transducers 2021, and assemble them to obtain the annular acoustic suspension device 20 to be verified.

[0129] For example, a semi-cylindrical outer wall with a transducer base is made using 3D printing technology. Each transducer base has a diameter of 10mm and a depth of 5mm, which is used to stably install the transducer. Ultrasonic transducers are selected, and a circle of transducer rings are placed at fixed intervals along the axial direction inside the cylindrical outer wall, with a total of 5 layers, and each layer of transducer rings contains 8 transducers evenly distributed. Furthermore, a power supply system is designed, using a 7.5V DC regulated power supply, and the voltage is increased to 20V through an adjustable boost module, connected to the motor drive module, and then the Arduino Nano main control board generates a 40kHz square wave signal to control the emission sound pressure of each layer of transducers, so as to achieve precise control of the sound field. The device design ensures the formation of a stable Bessel-shaped sound field by adjusting the ring structure and transducer arrangement.

[0130] Step 5: Verify the linear acceleration process of the particle material of the annular acoustic suspension device to be verified by computer simulation and acoustic propulsion experiment respectively; compare the verification results of computer simulation and acoustic propulsion experiment, and optimize the design parameters of the annular acoustic suspension device 20.

[0131] Specifically, the acoustic propulsion process of the moving potential well is verified using computer simulation and experiments to ensure that the velocity and acceleration of the particle are almost equal to the velocity and acceleration of the potential well, and the design parameters of the annular acoustic levitation device 20 are optimized to achieve a stable moving potential well.

[0132] Specifically, Comsol software is used to simulate the acoustic propulsion process with gradually decreasing sound intensity to verify its feasibility, and the influence of decreasing sound pressure on particle stability and movement speed is verified through experiments to optimize the design parameters of the annular acoustic suspension device 20.

[0133] In this embodiment, the design parameters of the annular acoustic suspension device are determined by single-ring sound field simulation and multi-ring sound field simulation, and the two semi-cylindrical outer walls with transducer bases are manufactured by 3D printing technology. Two semi-cylindrical outer walls with transducer bases and multiple transducers are manufactured by 3D printing technology, and the annular acoustic suspension device to be verified is assembled. The linear acceleration process of the particulate matter of the annular acoustic suspension device to be verified is verified by computer simulation and acoustic propulsion experiments respectively; the verification results of computer simulation and acoustic propulsion experiments are compared to optimize the design parameters of the annular acoustic suspension device. In this embodiment, the feasibility and effectiveness of the technical solution are ensured through detailed simulation and experimental verification, and reliable data support and theoretical basis are provided. By optimizing the design parameters of the annular acoustic suspension device, the accuracy and reliability of the linear acceleration acoustic propulsion are improved.

[0134] The linear acceleration acoustic propulsion method provided in this embodiment includes: the control device outputs a control signal corresponding to each transducer to each transducer, and the control signal is used to control the emission sound pressure and phase relationship of each layer of transducer ring; each transducer generates a sound wave in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of particulate matter. In this embodiment, the control device outputs a control signal to each transducer to control the emission sound pressure and phase relationship of each layer of transducer ring, which can achieve precise control of the sound field distribution and potential well position; each transducer generates a sound wave in response to receiving the control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of particulate matter. It can be seen that the scheme of this embodiment realizes efficient and stable linear acceleration and propulsion of particulate matter in the air medium, and provides an innovative solution for deep space exploration and small thrust missions in a thin atmosphere.

[0135] Furthermore, in one embodiment, the linear acceleration acoustic propulsion method includes the following steps.

[0136] First, the semi-cylindrical outer wall with the transducer base is made using 3D printing technology to ensure the stable installation of the transducer.

[0137] Furthermore, ultrasonic transducers are selected to be assembled into a multi-layer transducer ring, and each layer ensures that the transducers are evenly distributed on the ring.

[0138] Furthermore, the circuit connection of the propulsion device is completed, including the DC regulated power supply, boost module, motor drive module and main control board, to ensure that the power supply and control signal connection of each transducer ring is stable and reliable.

[0139] Further, granular matter is prepared as a medium, which is injected into the device.

[0140] Finally, by controlling the main control board to generate a square wave signal, the emission sound pressure and phase relationship of each layer of transducer ring are adjusted to realize the acoustic propulsion scheme with a moving potential well and a gradually decreasing sound intensity, so that the particulate matter can be accelerated in the wave field space and the required reverse thrust can be obtained.

[0141] In this embodiment, precise device design, stable circuit connection and fine sound wave control are combined to achieve efficient and stable linear acceleration propulsion of particulate matter.

[0142] In addition, in order to further illustrate the beneficial effects of the present invention, a particle acceleration experiment in a zero-order Bessel sound field and an experiment on forming an energy channel in a first-order Bessel sound field were conducted to verify the beneficial effects of the present invention.

[0143] For the particle acceleration experiment in the zero-order Bessel acoustic field. Specifically, Figure 4 Schematic diagram of an acoustic propulsion device based on a mobile potential well provided by the present invention, such as Figure 4 As shown in the figure, the linear acceleration acoustic propulsion system uses the following equipment: a 3D printed semi-cylindrical outer wall with a transducer base, a 10mm diameter ultrasonic transducer with a frequency of 40kHz, a DC regulated power supply, an LTC1871 adjustable boost module, an L298N motor drive module, an Arduino Nano main control board and Potentiometer.

[0144] The device is powered by a 7.5V DC regulated power supply. The Arduino Nano main control board generates a 40kHz square wave signal. The LTC1871 boost module increases the voltage of 7.5V to 20V, and a potentiometer is connected to adjust the input voltage of the L298N driver module. The square wave signal generated by the Arduino Nano main control board is connected to the L298N driver module to amplify the signal, and finally a square wave signal with a peak-to-peak value of up to 20V is generated. The peak-to-peak value of the square wave signal can be adjusted by the corresponding potentiometer. Three layers of transducer rings are fixed in the outer walls of the two semi-cylinders, and they are assembled to form a cylinder.

[0145] After assembling the experimental device, conduct the following experiments: (a) Single ring suspension experiment

[0146] Only open the middle ring, put in the granular material, observe the suspension position of the granular material, and test the stability of the particles.

[0147] (b) Particle movement experiment

[0148] If the experiment (a) is consistent with the simulation results, put the particles in, adjust the potentiometer according to the designed process to adjust the emission sound pressure of each layer of rings, observe whether the behavior of the particles in a movement cycle is consistent with the simulation results, record the movement distance of the particles, and compare with the simulation results. In experiment (a), the particle diameter is about 3mm. The experiment found that when only the second layer of rings is turned on, the particles can be suspended between the first and second layers of rings and between the second and third layers of rings, and the position is closer to the first and third layers of rings. Figure 5 Schematic diagram of the suspension of particles by the zero-order Bessel sound field provided by the present invention, such as Figure 5 As shown, the simulation results are consistent with the experimental results. Potential wells are generated above and below the second-layer ring, and their positions are very close to those in the experimental results.

[0149] The stability of particle suspension was tested. After a slight disturbance to the particles, the particles were very likely to oscillate along the angular direction. Figure 6 Schematic diagram of the zero-order Bessel acoustic field suspension stability experiment provided by this application. Figure 6 This phenomenon verifies that the potential well of the zero-order Bessel acoustic field is an annular potential well, and the potential well has stable constraints in both radial and axial directions.

[0150] Based on this phenomenon, we redesigned a way to move the potential well: Assume that rings a, b, and c are arranged in sequence, with ring b in the middle. In the initial state, ring a is opened to 100%, and rings b and c are closed, then a potential well will be formed between rings a and b. After starting to move the potential well, first increase the sound pressure emitted by ring c from 0 to 100%, then the potential well will move from the middle of rings a and b to the middle of ring b; then reduce the sound pressure emitted by ring a from 100% to 0, then the potential well will move from the middle of ring b to the middle of rings b and c. This alternating control can also achieve the purpose of moving the potential well.

[0151] The experimental results of controlling particle movement are as follows Figure 7 As shown, Figure 7 It is a schematic diagram of the potential well movement experimental process of double-loop control provided by the present invention. Figure 7 The voltage of the 2nd and 4th rings and the position of the particles are recorded in the figure. The particle diameter is about 3mm, the maximum voltage is about 20V, and the scale is 2mm per grid. Figure 7 (a) to Figure 7 (b), the particle moved about 1.5 grids, about 3 mm; Figure 7 (b) to Figure 7 (c), the particle moves about 2 grids, about 4mm, and a total of 7mm. Then make a graph of the change of the lowest point position of the potential well during half a cycle as the moving cycle progresses, as shown in Figure 8 As shown, Figure 8 Schematic diagram of the change of the lowest point position of the acoustic field potential well provided by the present invention with the voltage ratio of the second layer ring. Figure 8As can be seen in the figure, the experimental results are in good agreement with the simulation results. Since the scale may affect the acoustic field and particle motion, the particle movement distance measured by the experimental results may not be accurate, but it is sufficient to prove that this method can effectively move the potential well, thereby driving the particles forward, verifying the feasibility of the acoustic propulsion method based on the moving potential well.

[0152] Experiment on forming energy channels for the first-order Bessel sound field. Specifically, Fig. 9 Schematic diagram of a five-layer first-order Bessel morphoacoustic suspension device provided by the present application. Fig. 9 As shown in the figure, the experimental device uses the following equipment: a 3D printed semi-cylindrical outer wall with a transducer base, an ultrasonic transducer with a diameter of 10mm and a frequency of 40kHz, a DC regulated power supply, an LTC1871 adjustable boost module, an L298N motor driver module, and an FPGA main control board. The assembled experimental equipment is shown in Figure 1. The device is powered by a 7.5V DC regulated power supply. The FPGA main control board generates eight 40kHz square wave signals with a phase difference of π / 4 between each other. The LTC1871 boost module increases the voltage of 7.5V to 15V, and a potentiometer is connected to adjust the input amplification voltage of the L298N driver module. The square wave signal generated by the ArduinoNano is connected to the L298N driver module to amplify the signal, and finally a square wave signal with a peak-to-peak value of 15V is generated. Five layers of transducer rings are fixed in the outer walls of the two semi-cylinders, and they are assembled to form a cylinder. The two signals with a phase difference of π are connected to the positive and negative electrodes of a column of transducers respectively, and the circuits are connected in sequence. Finally, the signals at both ends of each transducer are square wave signals with a peak-to-peak value of 30V.

[0153] After assembling the experimental device, conduct a multi-ring suspension experiment: open the device, put in foam particles, observe the suspension position of the particles, observe their stability after disturbance, and calculate the size of the restraining force. Then put in a small foam stick and observe the suspension phenomenon of the device on a long object.

[0154] For the foam particles, more than five stable suspension points were observed on the axis, which were located in the center of each ring layer and between the 2nd and 3rd ring layers and the 3rd and 4th ring layers. Fig.10 Schematic diagram of the suspension points on the axis of the five-layer first-order Bessel-shaped acoustic suspension device provided by the present invention, such as Fig.10 As shown in the figure, there are five suspension points in the center of the ring, and the suspended particles will rotate at high speed in the tube. In particular, the stability of the two suspension points between the rings is slightly weaker than that of the suspension point in the center of the ring. The particle suspension experiment verifies the simulation results of the single-ring Bessel-shaped acoustic field.

[0155] To explore the stability of the suspension, a particle with a diameter of about 3 mm suspended on the axis was perturbed, and the process of its recovery to a stable state was recorded with a high-speed camera at a frame rate of 4352fps. The acceleration was calculated using the second-order difference. The results are as follows: Fig.11 As shown, Fig.11 This is a schematic diagram of the recovery of particles after perturbation in the first-order Bessel-shaped acoustic suspension device provided by the present invention. In this process, the maximum displacement is about 2mm, and the maximum acceleration is close to 4000m / s2. It is calculated that the maximum restraining force in this process is about 3mN. Due to the uncertainty of perturbation, the maximum restraining force in this process may be different from the maximum restraining force of the potential well, but it is enough to show that the potential well has sufficient stability to restrain the particulate matter.

[0156] A small foam stick with a diameter of about 3 mm was placed in the tube, and it was found that the foam stick could be suspended on the central axis and rotate at high speed. Fig.12 FIG. 1 is a schematic diagram of a foam stick provided by the present invention being suspended on an axis. Fig.12 As shown in the figure, it is found that the stick is almost free from constraints in the axial direction. After the device is tilted, it will fall out under the action of gravity. During this period, the stick is always constrained on the axis. This experiment shows that the repulsive effect of the higher potential energy area on and near the axis on the stick is weaker than the constraint effect of the potential well on the stick, which verifies that there is a continuous potential well that is almost through on the axis of this device, which is consistent with the simulation results. At the same time, the successful constraint of the stick has given the device a new application scenario, which can be used in the design of low-friction shafts such as turboprops or air bearings.

[0157] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0158] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0159] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A linear acceleration acoustic propulsion system, characterized in that: include: control device and annular acoustic suspension device; The annular acoustic suspension device is assembled from two semi-cylindrical outer walls with transducer bases and multiple layers of transducer rings, each layer of transducer rings including multiple transducers; The control device is connected to each transducer, and the control device is used to output a control signal corresponding to each transducer to each transducer, and the control signal is used to control the emission sound pressure and phase relationship of each layer of transducer ring; Each transducer is used to generate sound waves in response to receiving a control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of the particle matter.

2. The linear acceleration acoustic propulsion system according to claim 1, characterized in that: The control device comprises: a main control board and a drive module; The main control board is connected to the driving module, and the main control board is used to output the intermediate control signal corresponding to each transducer to the driving module; The driving module is connected to each transducer, and is used for converting the intermediate control signal corresponding to each transducer into a control signal corresponding to each transducer, and outputting the control signal corresponding to each transducer to each transducer.

3. The linear acceleration acoustic propulsion system according to claim 1 or 2, characterized in that: The linear acceleration acoustic propulsion system further includes: a DC voltage-stabilized power supply and a boost circuit; The DC regulated power supply is used to output a DC voltage signal; The input end of the boost circuit is connected to the DC regulated power supply, and the output end of the boost circuit is connected to each transducer, for converting the DC voltage signal into a power supply signal adapted to each transducer.

4. A linear acceleration acoustic propulsion method, characterized in that: The invention is applied to a linear acceleration acoustic propulsion system, wherein the linear acceleration acoustic propulsion system comprises a control device and an annular acoustic suspension device; the annular acoustic suspension device is assembled from two semi-cylindrical outer walls with transducer bases and a multi-layer transducer ring, and each layer of the transducer ring comprises a plurality of transducers; the method comprises: The control device outputs a control signal corresponding to each transducer to each transducer, wherein the control signal is used to control the emission sound pressure and phase relationship of each layer of transducer ring; Each transducer generates a sound wave in response to receiving a control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of the particle matter.

5. The linear acceleration acoustic propulsion method according to claim 4, characterized in that: The Bessel sound field is a zero-order Bessel sound field or a first-order Bessel sound field.

6. The linear acceleration acoustic propulsion method according to claim 5, characterized in that: The control signal includes a zero-order Bessel sound field control signal; The control device outputs a control signal corresponding to each transducer to each transducer, specifically including: The control device outputs a zero-order Bessel sound field control signal corresponding to each transducer to each transducer; Each transducer generates a sound wave in response to receiving a control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of the particulate matter, specifically including: Each transducer generates an acoustic wave in response to receiving a zero-order Bessel acoustic field control signal, and implements acoustic propulsion based on a moving potential well, so as to achieve linear acceleration of the particle matter.

7. The linear acceleration acoustic propulsion method according to claim 5, characterized in that: The control signal includes a first-order Bessel sound field control signal; the control device outputs a control signal corresponding to each transducer to each transducer, specifically including: The control device outputs a first-order Bessel sound field control signal corresponding to each transducer to each transducer; Each transducer generates a sound wave in response to receiving a control signal, so that the annular acoustic suspension device generates a Bessel sound field to achieve linear acceleration of the particulate matter, specifically including: Each of the transducers generates a sound wave in response to receiving a first-order Bessel sound field control signal, and realizes sound propulsion with a sound intensity decreasing layer by layer, so as to achieve linear acceleration of the particulate matter.

8. The linear acceleration acoustic propulsion method according to claim 4, characterized in that: The method further comprises: Through single-ring sound field simulation, the radius of the transducer ring and the radius of the semi-cylindrical outer wall are determined; Determine the spacing between adjacent transducer ring layers through multi-ring acoustic field simulation; Based on the design parameters of the annular acoustic suspension device, the two semi-cylindrical outer walls with transducer bases are manufactured by 3D printing technology; the design parameters of the annular acoustic suspension device include the radius of the transducer ring, the radius of the semi-cylindrical outer wall and the spacing between adjacent transducer ring layers.

9. The linear acceleration acoustic propulsion method according to claim 8, characterized in that: After the two semi-cylindrical outer walls with transducer bases are manufactured by 3D printing technology based on the radius of the transducer ring, the radius of the semi-cylindrical outer wall and the spacing between adjacent transducer ring layers, the method further includes: The two semi-cylindrical outer walls with transducer bases and a plurality of transducers are manufactured by 3D printing technology, and assembled to obtain the annular acoustic suspension device to be verified; Verifying the linear acceleration process of the particle material of the annular acoustic suspension device to be verified by computer simulation and acoustic propulsion experiment respectively; By comparing the verification results of computer simulation and acoustic propulsion experiments, the design parameters of the annular acoustic suspension device are optimized.

10. The linear acceleration acoustic propulsion method according to any one of claims 4 to 9, characterized in that: The control signal is a square wave signal.

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