Atomizing device, atomizing method and use

Abstract

The application provides an atomization device, an atomization method and application, and belongs to the technical field of atomization. The application comprises a sound vortex generation system for generating a vortex ultrasonic field; and a liquid supply system for conveying an atomization medium into the vortex ultrasonic field. The sound vortex generation system is used to generate a vortex ultrasonic field, and the vortex ultrasonic field has both the atomization capacity of an ultrasonic standing wave field and the atomization capacity of centrifugal atomization, so that the atomization medium can be atomized. The application has a wide application prospect in the fields of ordinary liquid atomization and metal powder production.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of atomization technology, in particular to an atomization device based on vortex ultrasonic field, an atomization method and application thereof. BACKGROUND

[0002] Generally, the ultrasonic atomization technology is to directly contact the liquid to be atomized with a high-frequency vibrating surface. The liquid oscillates on the ultrasonic vibrating surface, breaks and separates, and is atomized. This contact type ultrasonic atomization technology is simple and direct, but also has some unavoidable limitations, such as contamination of the atomized liquid, cavitation corrosion of the vibrating end surface, and only low-temperature liquid can be processed. In order to overcome these shortcomings, non-contact ultrasonic atomization is a very potential development direction.

[0003] At present, the non-contact ultrasonic atomization technology is mainly non-contact ultrasonic standing wave field atomization technology. This technology uses an ultrasonic vibrating end and an opposite placed reflecting end, or two opposite placed ultrasonic vibrating ends, to generate a strong standing wave field. The liquid is flattened, oscillated, broken and atomized at the acoustic pressure node. In 1991, Lierke et al. first proposed a non-contact ultrasonic atomization method using an emitting end and an opposite placed reflecting end, and applied for an ultrasonic standing wave atomization device for atomizing molten metal. In 1996, K. Bauckhage et al. first proposed using a double emitting end ultrasonic standing wave field to atomize liquid, and obtained 10-20 μm spherical tin powder. Since then, scientists have improved the non-contact ultrasonic standing wave field atomization technology by changing the shape of the transducer end face, using multi-pipe input fluid, etc. Domestic research on non-contact atomization started late. Harbin Institute of Technology carried out research on ultrasonic standing wave atomization, theoretically analyzed the characteristics of the acoustic field, established the overall scheme of the ultrasonic standing wave atomization system, and carried out atomization experiments of glycerol and aqueous solution. Through the establishment of the acoustic field simulation model and the droplet atomization model coupled with the acoustic field and two-phase flow, the droplet breaking mechanism and critical conditions were analyzed, and the influence of various parameters on the droplet atomization process was studied. In addition, they also proposed a molten metal ultrasonic standing wave non-contact atomization powder making device and method. However, the atomization capacity of the ultrasonic standing wave field is still low, and the application range is extremely limited.

[0004] Recent studies have shown that under certain conditions, sound waves can form a vortex acoustic field carrying orbital angular momentum, and the wave front presents a spiral change about the zero field strength center. In a gas medium, the vortex acoustic field can not only suspend high-density objects but also drive the suspended objects to rotate at high speed. In view of this, the vortex ultrasonic field has both the atomization capacity of the ultrasonic standing wave field and the centrifugal atomization capacity. SUMMARY

[0005] Therefore, in order to solve the problem of low atomization capacity of the ultrasonic standing wave field in the prior art, the present application provides an atomization device, which utilizes a sound vortex generation system to generate a vortex ultrasonic field, and utilizes the vortex ultrasonic field to atomize the atomization medium, which has both the atomization capacity of the ultrasonic standing wave field and the centrifugal atomization capacity, and the atomization can be efficiently performed, and has a wide application prospect in the fields of ordinary liquid atomization and metal powder production.

[0006] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions.

[0007] An atomization device comprises:

[0008] A sound vortex generation system is configured to generate a vortex ultrasonic field.

[0009] A liquid supply system is configured to deliver an atomization medium into the vortex ultrasonic field.

[0010] Preferably, the sound vortex generation system comprises an ultrasonic generation assembly and a vortex field acoustic atomization assembly connected to the ultrasonic generation assembly.

[0011] The ultrasonic generation assembly comprises a signal generator, a power amplifier and an electro-acoustic transducer.

[0012] The power amplifier amplifies the signal output by the signal generator to drive the electro-acoustic transducer to work.

[0013] The vortex field acoustic atomization assembly comprises an ultrasonic vibration end, which is connected to the electro-acoustic transducer, and the emission ends of the ultrasonic vibration end are arranged in rotational symmetry around a same point and a same axis in space, and are configured to emit ultrasonic waves to superimpose to form the vortex ultrasonic field in the region surrounded by the ultrasonic vibration end.

[0014] Preferably, the phases of the electro-acoustic transducers change in turn in a counterclockwise or clockwise direction, and the phase difference between adjacent electro-acoustic transducers is equal.

[0015] Preferably, the number of the ultrasonic vibration ends is at least 3, and the ultrasonic vibration ends are arranged in an array and work at the same frequency.

[0016] Preferably, the number of the ultrasonic vibration ends is 4, and each ultrasonic vibration end passes through a circular hole on a constraint pipe to enter the internal region surrounded by the constraint pipe.

[0017] Preferably, the atomization device further comprises a vacuum system configured to control the vacuum degree and / or a temperature control system configured to control the atomization temperature.

[0018] Preferably, the atomization medium is one of water, oil and metal liquid.

[0019] Preferably, the atomization device further comprises a collection system.

[0020] In a second aspect, the present application provides a method for atomizing the atomizing device as described above, comprising the following steps:

[0021] Step (1), the acoustic vortex generating system generates a vortex ultrasonic field;

[0022] Step (2), the liquid supply system sends the atomizing medium into the vortex ultrasonic field for atomization.

[0023] In a third aspect, the present application provides the application of the atomizing device and / or the atomizing method in the field of general liquid atomization and metal liquid powder production.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] The present application first proposes a method for non-contact atomization of liquid medium by using acoustic vortex field. Since the vortex ultrasonic field has the ability of ultrasonic standing wave field atomization and centrifugal atomization, the atomization efficiency of the atomizing medium can be effectively improved. Not only the general liquid has good atomization effect, but also the problem of difficult to obtain fine powder with a particle size of 50 μm or less in the traditional non-contact ultrasonic atomization for preparing metal powder is solved. The energy utilization rate, sphericity, particle size controllability, particle size range and other problems in the implementation process of the existing powder production technology are effectively optimized, and the anti-pollution and anti-oxidation effect in the powder production process is greatly improved, which has a wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the present application.

[0027] Figure 2 It is a schematic diagram of the formation of the vortex ultrasonic field.

[0028] Figure 3 It is the atomization process of water droplets.

[0029] Figure 4 It is the atomized particle size and particle size distribution diagram of water droplets.

[0030] Figure 5 It is the atomization process of glycerol droplets.

[0031] Figure 6 It is the atomized particle size of glycerol droplets.

[0032] Figure 7 It is the SEM image and particle size distribution curve of the particles after atomization of pure tin (Sn, melting point 232℃).

[0033] In the figure, 100, device body; 101, working chamber; 200, liquid supply system; 201, liquid containing bottle or smelting crucible; 202, gas supply device; 2021, gas cylinder; 2022, gas inlet pipe; 2023, gas regulating valve; 203, heating device; 300, ultrasonic generating assembly; 301, signal generator; 302, power amplifier; 303, electroacoustic transducer; 400, vortex field acoustic atomization assembly; 401, ultrasonic vibration end; 4011, first ultrasonic vibration end; 4012, second ultrasonic vibration end; 4013, third ultrasonic vibration end; 4014, fourth ultrasonic vibration end; 402, constraint pipe; 500, collection system; 10, liquid to be atomized. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0035] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom end" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0036] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "provided with", "sleeved / connected", "connected" and the like should be broadly understood, for example, "connected" can be fixedly connected, or can be detachably connected, or integrally connected; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium; can be internal communication of two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0037] As Figures 1-2 shown, the present application provides an atomization device, comprising:

[0038] An acoustic vortex generating system for generating a vortex ultrasonic field, wherein the function of the acoustic vortex generating system is to generate an integer order or fractional order acoustic vortex;

[0039] The liquid supply system 200 is used for supplying atomized medium into the vortex ultrasonic field, wherein the liquid supply system 200 can supply the atomized liquid, such as water, oil, molten liquid, etc., to the center of the vortex sound field at a certain flow rate.

[0040] As shown in the figure, in the present application, the liquid supply system 200 is preferably used for supplying atomized medium into the vortex ultrasonic field, and the atomized medium is preferably ordinary liquid or molten liquid, which is contained in a liquid containing bottle or a smelting crucible 201. Figure 1

[0041] When the liquid supply system 200 supplies ordinary liquid (such as water, oil, etc.), the liquid supply system 200 preferably comprises a liquid containing bottle and a gas supply device 202, wherein the liquid containing bottle is used for containing the liquid to be atomized 10, and the gas supply device 202 is connected to the liquid containing bottle and is used for controlling the flow rate of the liquid to be atomized 10.

[0042] When the liquid supply system 200 supplies molten liquid (metal molten liquid), the liquid supply system 200 preferably comprises a smelting crucible, a gas supply device 202 and a heating device 203, wherein the smelting crucible is used for containing the molten liquid, the heating device 203 is arranged at the periphery of the smelting crucible and is used for heating the smelting crucible, and the gas supply device 202 is connected to the smelting crucible and is used for controlling the flow rate of the molten liquid.

[0043] The device body 100 of the atomization device provided by the present application preferably has a working chamber 101, wherein the acoustic vortex generating system and the liquid supply system 200 are located in the working chamber 101, the acoustic vortex generating system is preferably located below the liquid supply system 200, and the liquid droplets can directly fall into the center of the acoustic vortex field.

[0044] As shown in the figure, the present application provides an embodiment of the acoustic vortex generating system, wherein the acoustic vortex generating system comprises an ultrasonic generating assembly 300 and a vortex field acoustic atomization assembly 400 connected to the ultrasonic generating assembly 300. Figure 1

[0045] The ultrasonic generating assembly 300 comprises a signal generator 301, a power amplifier 302 and an electro-acoustic transducer 303.

[0046] The power amplifier 302 amplifies the signal output by the signal generator 301 to drive the electro-acoustic transducer 303 to work, and preferably works at the same frequency, amplitude and waveform, and the signal generator 301 is used for controlling the working frequency, amplitude, waveform and phase of the electro-acoustic transducer 303.

[0047] ​​The vortex field acoustic atomization assembly 400 comprises ultrasonic vibration ends 401 connected with the electro-acoustic transducers 303, and the emission ends of the ultrasonic vibration ends 401 are arranged in rotational symmetry around a same point and a same axis in space, for emitting ultrasonic waves to superimpose to form the vortex ultrasonic field in the area surrounded by the ultrasonic vibration ends 401.

[0048] In the present application, the phases of the electro-acoustic transducers 303 change in turn in a counterclockwise or clockwise direction, and the phase difference between adjacent electro-acoustic transducers 303 is equal, preferably 2 or an integer multiple (or a fractional multiple) of 2 divided by the number of electro-acoustic transducers 303.

[0049] In the present application, the number of ultrasonic vibration ends 401 is at least 3, and the ultrasonic vibration ends 401 are arranged in an array and work at the same frequency, preferably work at the same frequency, amplitude and waveform.

[0050] In the present application, the number of ultrasonic vibration ends 401 is 4, and each ultrasonic vibration end 401 passes through a circular hole on the constraint pipe 402 to enter the internal area surrounded by the constraint pipe 402, wherein the constraint pipe 402 is preferably placed at the periphery of the annular array of ultrasonic vibration ends 401. Each ultrasonic vibration end 401 passes through a circular hole on the constraint pipe 402 to enter the internal area surrounded by the constraint pipe 402, wherein the constraint pipe 402 contains the emission end, which plays a role in increasing the intensity of the vortex acoustic field.

[0051] As shown in Figure 2 , the area where the liquid to be atomized 10 is located is the area where the vortex ultrasonic field is formed.

[0052] In the present application, the number of transducers is 4,

[0053] In the present application, a vacuum system for controlling the vacuum degree and / or a temperature control system for controlling the atomization temperature are further included, and preferably a cooling assembly is further included. The temperature control assembly and the cooling assembly are preferably arranged at the periphery of the vortex field acoustic atomization assembly 400. The temperature control assembly is used to monitor the real-time temperature in the working chamber 101, to ensure the normal work of the acoustic vortex generation system and to make the acoustic field in a resonant state. The temperature control assembly can be selected from conventional temperature control assemblies in the art, and no special requirements are required. The cooling assembly is used to cool the working chamber 101, and can be selected from conventional cooling assemblies in the art, and no special requirements are required.

[0054] In the present application, the atomization medium is a liquid comprising water, oil and metal melt.

[0055] In the present application, a collecting system 500 is also included, which is preferably located below the acoustic vortex generating system, for collecting fine liquid droplets or metal fine powder.

[0056] The working chamber 101 of the atomization device provided by the present application is preferably connected with an inert gas cylinder 2021, so as to ensure that the working chamber 101 is in an inert gas protection environment.

[0057] In a second aspect, the present application provides an atomization method of the atomization device, which comprises the following steps:

[0058] Step (1), the acoustic vortex generating system generates a vortex ultrasonic field;

[0059] Step (2), the liquid supply system 200 sends the atomization medium into the vortex ultrasonic field for atomization. The temperature, flow rate and atmosphere at the center of the vortex ultrasonic field can be respectively controlled by a temperature control assembly, a gas supply device 202 and an inert gas cylinder 2021.

[0060] In a third aspect, the present application provides applications of the atomization device and / or the atomization method in the field of general liquid atomization and metal liquid powder preparation.

[0061] The technical solutions of the present application will be described in detail below with reference to specific embodiments. Embodiment 1

[0062] The liquid to be atomized 10 is pure water and glycerol, both of which do not need to be heated. The liquid supply system 200 mainly comprises a liquid containing bottle and a gas supply device 202. The gas supply device 202 comprises a gas cylinder 2021, a gas inlet pipe 2022 and a gas regulating valve 2023. The gas cylinder 2021 provides high-pressure gas, which is generally inert gas. The gas regulating valve 2023 controls the gas flow. A numerical control gas flow meter can be selected for this part. The gas flow changes with different types of liquid droplets. The inert gas enters the liquid containing bottle through the gas inlet pipe 2022. Under the action of pressure, the liquid droplets flow out of the bottom hole of the liquid containing bottle and enter the acoustic vortex field.

[0063] If the liquid to be atomized 10 is pure water, the collecting system 500 is a glass sheet coated with silicon oil. If the liquid to be atomized 10 is glycerol, the collecting system 500 is a dry glass sheet, which are both directly placed below the atomization position.

[0064] The specific implementation steps are as follows:

[0065] Step one: pour pure water or glycerol into the liquid containing bottle, and place the collecting system 500 below the vortex field acoustic atomization assembly 400.

[0066] Step two: turn on the ultrasonic atomization system. First, input the relevant control parameters on the signal generator 301. In this embodiment, the frequency used is 23 kHz, the amplitude is 20 Vpp, the waveform is a sine wave, the number of electroacoustic transducers 303 is 4, which are the first, second, third and fourth electroacoustic transducers, corresponding to the control of four ultrasonic vibration ends 401, respectively. The four ultrasonic vibration ends 401 are named the first ultrasonic vibration end 4011, the second ultrasonic vibration end 4012, the third ultrasonic vibration end 4013 and the fourth ultrasonic vibration end 4014. The phase of the first electroacoustic transducer is 0°, the phase of the second electroacoustic transducer is 90°, the phase of the third electroacoustic transducer is 180°, and the phase of the fourth electroacoustic transducer is 270°. The four-way signal output is amplified by the power amplifier 302, and the four-way amplified voltage is adjusted to 600 V. The electroacoustic transducer 303 converts the electrical signal into a vibration signal emitted by the ultrasonic vibration end with an end face diameter of 10 mm, generating a sound vortex field in the array surrounding area. The constraint pipe 402 has a diameter of 18.9 mm and is placed outside the transducer array.

[0067] Step three: turn on the gas supply device 202. Nitrogen gas is provided by the gas cylinder 2021 of the gas supply device 202, and the gas flow is controlled by the gas regulating valve 2023. The gas flow of pure water is about 500 sccm, and the gas flow of glycerol is about 1000 sccm. The nitrogen gas enters the liquid container through the gas inlet pipe 2022.

[0068] Step four: under the action of pressure, the liquid droplets are dropped into the sound vortex field at a flow rate of 2

[0069] Step five: the atomized liquid droplets fall freely in the constraint pipe 402 and are collected by the collection system 500 at the bottom of the operation chamber 101.

[0070] The specific implementation results are as follows:

[0071] Figures 3-4 The whole process of atomization of water droplets and glycerol is shown respectively, Figures 5-6 The particle size and distribution of the atomized water droplets and glycerol are shown respectively. The spread diameter of the water droplets is normally distributed, concentrated in 20-40 The spread diameter of glycerol is larger than that of water droplets. Example 2

[0072] ​The solid pure tin alloy is solid at room temperature and needs to be heated and melted. The liquid supply system 200 includes a smelting crucible, a gas supply device 202 and a heating device 203, and needs a cooling assembly, a temperature control assembly and an inert gas protection environment. The smelting crucible is used to contain solid metal or molten metal liquid. The heating device 203 includes a transformer and a resistance wire, the resistance wire is connected to the transformer and wound around the periphery of the smelting crucible, and is used to heat the smelting crucible. The temperature control assembly and the cooling assembly are arranged outside the constraint pipe 402 of the vortex field acoustic atomization assembly 400. The working chamber 101 is an inert gas protection environment. The collection system 500 is a funnel-shaped container arranged below the constraint pipe 402 and used to collect the metal powder after being broken and atomized by the acoustic vortex field.

[0073] Specific implementation steps

[0074] Step one: place the solid pure tin metal in the smelting crucible, and fill the working chamber 101 with high-purity inert gas to ensure that the pressure in the working chamber 101 is less than or equal to 1 MPa. The collection system 500 is arranged below the vortex field acoustic atomization assembly 400.

[0075] Step two: turn on the heating device 203, and set the transformer voltage to 10 V.

[0076] Step three: turn on the temperature control assembly to monitor the temperature change of the vortex field acoustic atomization assembly 400 in real time. When the temperature is higher than 60℃, turn on the cooling assembly to ensure that the temperature of the vortex field acoustic atomization assembly 400 is 20-60℃.

[0077] Step four: turn on the ultrasonic atomization system, which is the same as step two in the specific embodiment 1.

[0078] Step five: after the metal in the smelting crucible is melted, turn on the gas supply device 202. The principle and use steps of the gas supply device 202 are the same as those in step three of the specific embodiment 1. Nitrogen gas is provided by the gas cylinder 2021 of the gas supply device 202, the gas flow is controlled by the gas regulating valve 2023 to about 800 sccm, and the nitrogen gas enters the liquid containing bottle through the gas inlet pipe 2022.

[0079] Step six: under the action of pressure, the metal liquid droplets drop into the acoustic vortex field at a flow rate of 2 Step seven: the atomized metal liquid droplets freely fall in the constraint pipe 402, naturally cool and solidify into metal powder with high sphericity and small particle size, and are collected by the collection system 500 at the bottom of the working chamber 101.

[0080] Step seven: the atomized metal liquid droplets freely fall in the constraint pipe 402, naturally cool and solidify into metal powder with high sphericity and small particle size, and are collected by the collection system 500 at the bottom of the working chamber 101.

[0081] Specific implementation results:

[0082] Figure 7The SEM image and the particle size distribution curve of the particles of the pure tin metal atomized by the acoustic vortex field are shown. It is found that the particles are mainly spherical. The particle diameter also shows a normal distribution, mainly concentrated in 30-40 .

[0083] The above is only a preferred specific embodiment of the present application; however, the protection scope of the present application is not limited thereto. Any person skilled in the art, according to the technical solution and the improvement concept of the present application, makes equivalent replacement or change within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. An atomizing device, characterized in that, include: Acoustic vortex generation system, used to generate vortex ultrasonic fields; A liquid supply system is used to deliver atomized medium into the vortex ultrasonic field; The acoustic vortex generating system is located below the liquid supply system, ensuring that the atomized medium falls directly into the center of the vortex ultrasonic field. The acoustic vortex generating system includes an ultrasonic generating component and a vortex field acoustic atomizing component connected to the ultrasonic generating component. The ultrasonic generating assembly includes a signal generator, a power amplifier, and an electroacoustic transducer; The power amplifier amplifies the signal output by the signal generator to drive the electroacoustic transducer to work. The vortex field acoustic atomization component includes an ultrasonic vibration end, which is connected to the electroacoustic transducer. The transmitting ends of the ultrasonic vibration end are arranged symmetrically around the same point and the same axis in space, and are used to emit ultrasonic waves that are superimposed in the area enclosed by the ultrasonic vibration end to form the vortex ultrasonic field. The phase of the electroacoustic transducer changes sequentially in a counterclockwise or clockwise direction, and the phase difference between adjacent electroacoustic transducers is equal. The number of ultrasonic vibration ends is 4, and each ultrasonic vibration end passes through a circular hole on the constraint pipe and enters the internal area enclosed by the constraint pipe. It also includes a vacuum system for controlling the vacuum level and / or a temperature control system for controlling the atomization temperature; It also includes a collection system located below the acoustic vortex generating system.

2. The atomizing device according to claim 1, characterized in that, The ultrasonic vibration ends are arranged in an array and operate at the same frequency.

3. The atomizing device according to claim 1, characterized in that, The atomizing medium is a liquid containing water, oil, and molten metal.

4. The atomization method of the atomizing device according to any one of claims 1-3, characterized in that, Includes the following steps: Step 1: The acoustic vortex generation system generates a vortex ultrasonic field; Step 2: The liquid supply system delivers the atomizing medium into the vortex ultrasonic field for atomization.

5. The application of an atomizing device according to any one of claims 1-3 in the fields of ordinary liquid atomization and metal liquid powder production.

6. The application of the atomization method according to claim 4 in the fields of ordinary liquid atomization and metal liquid powder production.

Images