Variable-channel plasma hybrid discharge device

Abstract

The invention provides a variable-channel plasma mixed discharge device. The variable-channel plasma mixed discharge device comprises a gas inlet, a gas inlet cavity, a knob, a gas mixing cavity, a high-voltage electrode, a plasma discharge needle tube, a cavity cover, an insulating plate, a plasma activation cavity, a negative electrode copper plate, a grounding electrode, a water outlet, a rubber tube and an atomizer. The number of the gas inlet channels can be changed by rotating the knob, gas enters from the gas inlet, is mixed in the gas mixing cavity and is discharged from the bottom of the discharge needle tube, redundant gas can be discharged from the gas outlet, and water can be added into the plasma activation cavity through the water inlet. A high-voltage electric field is formed between the plasma discharge needle tube and the negative electrode copper plate, mixed discharge can be formed by adding the insulating plate, gas discharged by the discharge needle tube is ionized to generate low-temperature plasma, and the low-temperature plasma is in contact with water in the plasma activation cavity to form plasma activated water. Finally, the activated water in the water outlet is conveyed into an atomizer through a rubber pipe to be atomized into mist, and the mist is sprayed to the surfaces of fruits and vegetables.

Description

Technical Field

[0001] The invention belongs to the field of low-temperature plasma physics and its application, and in particular relates to a variable-channel plasma mixed discharge device. Background Art

[0002] In modern agriculture, pesticides are widely used. However, the large-scale use of pesticides poses a serious threat to human health and the environment. At the same time, the preservation of agricultural products during transportation is also very important. Therefore, there is an agricultural demand for removing residual pesticides in fruits and vegetables and preserving them.

[0003] Applying high voltage to two electrodes to break down the gas therein can obtain low-temperature plasma, which contains active oxygen ions and high-energy free radicals. When low-temperature plasma comes into contact with water, plasma-activated water will be produced. The original chemical composition of the water will change, including conductivity and redox potential, as well as the formation of an acidic environment and the production of high levels of active oxygen and active nitrogen. Therefore, plasma-activated water can not only oxidize and degrade pesticide residues, but also undergo oxidation reactions with proteins and nucleic acids in bacteria, molds, spores and viruses, causing denaturation of proteins and nucleic acids in their bodies, thereby killing these microorganisms and playing a certain role in preserving fruits.

[0004] According to the specific usage scenario, different types and quantities of gases need to be supplied to generate different plasmas. Therefore, it is best to switch the number of air inlet channels at the front end of the plasma generating device to change the number and type of incoming gases. Sometimes it is necessary to change the discharge type to change the discharge effect and obtain different types of plasma. At the same time, in order to make the plasma-activated water better contact with the target residue, a simpler, easier-to-use and more efficient application method is needed. The atomizer can atomize the plasma-activated water into a spray and spray it onto the surface of fruits and vegetables, so that the plasma-activated water flows into its pores and surface gaps. Summary of the invention

[0005] The purpose of the present invention is to provide a simple, easy-to-use and efficient variable channel plasma mixed discharge device to solve the above problems. To achieve the above purpose, the present invention provides the following technical solutions: A variable channel plasma mixed discharge device, characterized in that: from top to bottom, there are an air inlet, an air inlet cavity, a knob, a gas mixing cavity, a high voltage electrode, a plasma discharge needle tube, a cavity cover, an insulating plate, a plasma activation cavity, a grounding electrode, a water outlet, a rubber tube, and an atomizer; there are three air inlets, one of which is located at the center of the air inlet cavity, and the other two are at the same distance from the center and form a right angle with the center line; the air inlet cavity is a solid quartz structure; the knob is made of solid quartz material, and has three knob channels and two grooves that pass through from top to bottom, one knob channel is located at the center of the knob, and the other two knob channels are at the same distance from the center and form a right angle with the center line, and when the center of the knob is taken as the center of symmetry, the two grooves are respectively located at the symmetric positions of the two knob channels; the gas mixing cavity is A hollow quartz cavity with an opening at the top and 25 round holes at the bottom, and a positive copper plate with 25 round holes is placed at the bottom; the high-voltage electrode is a copper rod, which is connected to the positive copper plate; the plasma discharge needle tube is a hollow metal needle, the number of which is 25, arranged in five rows and five columns, and passes through the small holes at the bottom of the mixing cavity and the positive copper plate; the cavity cover is made of quartz material, has a water inlet and an exhaust port, and has a through hole at the center; the insulating plate is a solid quartz plate; the plasma activation cavity is a hollow quartz cavity with an opening at the top, and a negative copper plate is placed at the bottom; the grounding electrode is a copper rod, which is connected to the negative copper plate; the water outlet is located at the lower right side of the plasma activation cavity; the atomizer is connected to the water outlet through the rubber tube.

[0006] A variable channel plasma mixed discharge device, characterized in that: the three air inlets all have an outer diameter of 30 mm, an inner diameter of 20 mm, and a height of 30 mm; the diameter of the upper half of the air inlet cavity is 270 mm, the height is 50 mm, and the diameter of the lower half is 200 mm, and the height is 20 mm; the outer diameter of the upper half of the knob is 220 mm, the inner diameter is 200 mm, and the height is 50 mm, and the outer diameter of the lower half is 200 mm, the inner diameter is 180 mm, and the height is 10 mm.

[0007] A variable channel plasma mixed discharge device, characterized in that: the diameter of the high voltage electrode is 5 mm; the positive copper plate is 170 mm long, 170 mm wide and 5 mm thick; the outer diameter of the upper half of the mixing chamber is 270 mm, the height is 50 mm, the diameter at the opening is 200 mm, the thickness of the cavity is 10 mm, the diameter of the lower half is 200 mm, and the height is 15 mm; the 25 plasma discharge needle tubes have the same size, with an outer diameter of 8 mm, an inner diameter of 6 mm, a length of 135 mm, and a mutual spacing of 20 mm; the diameter of the insulating plate is 200 mm and the thickness is 10 mm.

[0008] A variable channel plasma mixed discharge device, characterized in that: the outer diameter of the upper part of the cavity cover is 400mm, the height is 15mm, the outer diameter of the lower part is 380mm, the height is 10mm, the diameter of the through hole at the center is 200mm, the outer diameter of the water inlet diameter and the exhaust port are both 40mm, and the inner diameter is 30mm; the diameter of the grounding electrode is 5mm; the negative copper plate is 260mm long, 260mm wide and 5mm thick; the outer diameter of the plasma activation cavity is 400mm, the opening diameter is 380mm, the height is 180mm, and the cavity thickness is 10mm; the outer diameter of the water outlet is 40mm, and the inner diameter is 30mm.

[0009] Compared with the prior art, the present invention has the following beneficial effects: 1. The variable channel plasma mixing discharge device has a variable channel gas mixing front end, which can change the number of gas intake channels by rotating the knob, and mix different gases at the gas mixing end to generate different plasmas; 2. The variable channel plasma mixed discharge device can change the discharge intensity by using different numbers of plasma discharge needles and different discharge voltages according to actual requirements, and change the discharge mode by adding an insulating plate; 3. The variable channel plasma mixed discharge device can adopt atomizing sheets of different specifications and different vibration frequencies according to actual requirements, thereby changing the action range and effect of the atomizer; 4. The variable channel plasma mixed discharge device can also be promoted and applied to other processing fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is the overall external view of the variable channel plasma mixing discharge device; Figure 2 This is a three-dimensional view of the disassembled structure of the variable channel plasma mixing discharge device; Figure 3 It is a three-dimensional view of the positive electrode discharge structure; Figure 4 It is a three-dimensional view of the structure of the mixing chamber 4; Figure 5 A three-dimensional view of the structure of the insulating board 4.2 after being cut in half; Figure 6 It is a three-dimensional view of the structure of the air intake cavity 1; Figure 7 It is a three-dimensional view of the structure of knob 3; Figure 8 A three-dimensional view of the structure with half of the air intake cavity 1 and the knob 3 cut away; In the figure: 1. Air inlet chamber; 2. Air inlet; 3. Knob; 4. Gas mixing chamber; 5. High-voltage electrode; 6. Cavity cover; 7. Water inlet; 8. Exhaust port; 9. Plasma activation chamber; 10. Ground electrode; 11. Atomizer; 12. Rubber tube; 13. Water outlet. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail by specific embodiments in conjunction with the accompanying drawings, wherein the same reference numerals represent the same components in each of the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0012] In the embodiment of the present invention, in order to make the description clearer, the “right side” direction is consistent with the direction where the atomizer 11 is located, and the “left side” direction is consistent with the direction where the ground electrode 10 is located.

[0013] Figure 1 This is the overall external view of the variable channel plasma mixed discharge device. Figure 2This is a three-dimensional view of the disassembled structure of the variable-channel plasma mixing discharge device. The entire device includes an air inlet chamber 1, an air inlet 2, a knob 3, a gas mixing chamber 4, a high-voltage electrode 5, a chamber cover 6, a water inlet 7, an exhaust port 8, a plasma activation chamber 9, a ground electrode 10, an atomizer 11, a rubber tube 12, and a water outlet 13. To ensure the airtightness between different components, the air inlet chamber 1, the knob 3, the gas mixing chamber 4, and the chamber cover 6 are divided into two parts, the upper part realizes the corresponding function of the structure, and the lower part is used to match other components. For example, the outer diameter of the lower part of the knob 3 is 200 mm, and the opening diameter of the upper part of the gas mixing chamber 4 is also 200 mm. When the knob 3 is placed on the gas mixing chamber 4, the lower part of the knob 3 can match the opening of the upper part of the gas mixing chamber 4. Therefore, the lower part of the air inlet chamber 1 and the opening of the upper part of the knob 3 are matched; the lower part of the knob 3 and the opening of the upper part of the gas mixing chamber 4 are matched; the lower part of the gas mixing chamber 4 and the central through hole of the chamber cover 6 are matched; the lower part of the chamber cover 6 and the opening at the top of the plasma activation chamber 9 are matched. The high voltage electrode 5 and the ground electrode 10 are both copper rods, and rubber is added to seal the joint between the high voltage electrode 5 and the gas mixing chamber 4, and rubber is added to seal the joint between the ground electrode 10 and the plasma activation chamber 9. The plasma activation chamber 9 is a hollow quartz chamber with an opening on the top, with an outer diameter of 400mm, an opening diameter of 380mm, a height of 180mm, a chamber thickness of 10mm, and a water outlet 13 with an outer diameter of 40mm and an inner diameter of 30mm on the lower right side; the chamber cover 6 has a water inlet 7 and an exhaust port 8, and a through hole in the center, the upper half of the chamber cover 6 has a diameter of 400mm and a height of 15mm, the lower half has a diameter of 380mm and a height of 10mm, the through hole in the center has a diameter of 200mm, the outer diameter of the water inlet 7 and the outer diameter of the exhaust port 8 are both 40mm, and the inner diameter is both 30mm; the ground electrode 10 has a diameter of 5mm; the negative copper plate 9.1 is 260mm long, 260mm wide, and 5mm thick. The negative copper plate 9.1 is placed at the bottom of the plasma activation chamber 9 and connected to the ground electrode 10. The rubber tube 12 connects the water outlet 13 and the atomizer 11, and its length can be adjusted according to actual needs. The atomizer 11 is composed of a plastic cavity 11.1 and a ceramic atomizer sheet 11.2. The high-frequency vibration of the ceramic atomizer sheet 11.2 atomizes the activated water in the plastic cavity 11.1 into water mist.

[0014] Figure 3The three-dimensional view of the positive electrode discharge structure is composed of a gas mixing chamber 4, a high-voltage electrode 5, a sealing rubber 5.1, a positive copper plate 4.1, a plasma discharge needle tube 4.3 and an insulating plate 4.2. The high-voltage electrode 5 has a diameter of 5 mm; the positive copper plate 4.1 is 170 mm long, 170 mm wide, and 5 mm thick, and has 25 circular holes arranged in 5 rows and 5 columns, all with a diameter of 8 mm and a mutual spacing of 20 mm; the plasma discharge needle tube 4.3 is a hollow metal needle, a total of 25 and the same size, arranged in 5 rows and 5 columns, with an outer diameter of 8 mm, an inner diameter of 6 mm, a length of 135 mm, and a mutual spacing of 20 mm.

[0015] Figure 4 The three-dimensional view of the structure of the mixing chamber 4 is a hollow quartz chamber with an opening on the top. The outer diameter of the upper part is 270mm, the height is 50mm, the diameter at the opening is 200mm, the thickness of the chamber is 10mm, the diameter of the lower part is 200mm, the height is 15mm, and there are 25 circular holes at the bottom, arranged in 5 rows and 5 columns, all with a diameter of 8mm, and a mutual spacing of 20mm. The positive copper plate 4.1 is placed at the bottom of the mixing chamber 4, the high-voltage electrode 5 penetrates into the mixing chamber 4 from the outside and then connects to the copper plate, and the plasma discharge needle tube 4.3 passes through the small hole at the bottom of the mixing chamber 4 and the positive copper plate 4.1, and is flush with the positive copper plate 4.1.

[0016] Figure 5 The three-dimensional view of the structure with half of the insulating plate 4.2 left after cutting. The insulating plate 4.2 is a solid quartz plate with a diameter of 200mm and a thickness of 10mm. To ensure that the needle tube can be inserted, 25 circular holes of the same size are punched on the top, arranged in five rows and five columns, with a diameter of 8mm, a depth of 5mm, and a mutual spacing of 20mm. To ensure that the gas can be transmitted from the top to the bottom, 25 circular holes are punched at the same position at the bottom, all with a diameter of 4mm and a depth of 5mm. The insulating plate 4.2 is detachable. When in use, the needle tube is inserted from the top. Since the diameter of the small hole at the bottom is smaller than the outer diameter of the needle tube, the needle tube will only be inserted to half the depth. The positive discharge structure and the negative copper plate 9.1 together constitute a plasma discharge device. The distance between the plasma discharge needle tube 4.3 and the bottom negative copper plate 9.1 is 50mm. The gas enters the mixing chamber 4 from the opening, mixes in the chamber, and then enters the plasma discharge needle tube through the small holes on the copper plate, and finally comes out from the bottom of the needle tube. If an insulating plate 4.2 is added, it comes out from the small holes at the bottom of the insulating plate 4.2. Since the high-voltage electrode 5 and the plasma discharge needle tube 4.3 are electrically connected through the copper plate, the voltage applied to the high-voltage electrode 5 will be transmitted to the plasma discharge needle tube 4.3. Similarly, the voltage applied to the ground electrode 10 will also be transmitted to the negative copper plate 9.1.

[0017] Figure 6This is a three-dimensional view of the structure of the air inlet chamber 1. The air inlet chamber 1 is a solid quartz structure, with an upper part diameter of 270 mm and a height of 50 mm, and a lower part diameter of 200 mm and a height of 20 mm. The air inlet chamber 1 has three air inlets, all of which have an outer diameter of 30 mm, an inner diameter of 20 mm and a height of 30 mm. One is the air inlet 2.1 located at the center of the air inlet chamber 1, and the other two air inlets are located on both sides, namely the air inlet 2.2 and the air inlet 2.3. The air inlet 2.2 and the air inlet 2.3 are 50 mm away from the central air inlet 2.1 and form a right angle with the line connecting the air inlet 2.1. At the bottom of the air inlet cavity 1, there are air outlets corresponding to the air inlets, both of which have an outer diameter of 30mm and an inner diameter of 20mm. Air outlet 1.1 corresponds to air inlet 2.1, air outlet 1.2 corresponds to air inlet 2.2, and air outlet 1.3 corresponds to air inlet 2.3. The height of air outlet 1.1 is 30mm, and a detachable plastic buckle 1.4 is provided at the bottom. The plastic buckle 1.4 is a hollow circular ring structure with an outer diameter of 50mm, an inner diameter of 40mm, and a thickness of 4mm. The two air outlets 1.2 and 1.3 next to it are shorter, with a height of 10mm.

[0018] Figure 7 The following is a three-dimensional view of the structure of knob 3. Knob 3 is made of solid quartz. The outer diameter of the upper part is 220mm, the inner diameter is 200mm, and the height is 50mm. The outer diameter of the lower part is 200mm, the inner diameter is 180mm, and the height is 10mm. Knob 3 has three knob channels and two grooves that run through from top to bottom. The diameters of all knob channels and grooves are 30mm. Knob channel 3.1 is located at the center of knob 3. Knob channel 3.2 and knob channel 3.3 are both 50mm away from the center and form a right angle with the line connecting the centers. In addition, with knob channel 3.1 as the center, there are two grooves of the same specifications at the symmetric positions of knob channel 3.2 and knob channel 3.3, namely groove 3.4 and groove 3.5. Both grooves are 50mm away from the center and have a depth of 10mm.

[0019] Figure 8The three-dimensional view of the structure with half of the air intake cavity 1 and the knob 3 cut off after the combination is completed. The cutting line is a straight line from the center of the groove 3.5 to the center of the knob channel 3.3, and the cutting is vertical. At the knob channel 3.1, the diameter of the upper half of the circular hole is 40mm and the depth is 15mm, ensuring that the air outlet 1.1 can be inserted into the knob channel 3.1. The diameter of the lower half of the circular hole is 50mm and the depth is 15mm, ensuring that the plastic buckle 1.4 can be placed. When combining the air intake cavity 1 and the knob 3, the air outlet 1.1 needs to be inserted into the knob channel 3.1 from the top first, and then the plastic buckle 1.1 needs to be put on the bottom of the air outlet 1.1 from the bottom. When switching the number of channels, you need to first pull the air inlet cavity 1 vertically upwards. Since the diameter of the upper part of the knob channel 3.1 is small, the plastic buckle will be blocked after it is lifted up 11mm. At this time, the air outlets 1.2 and 1.3 on both sides of the air inlet cavity 1 are also lifted up 11mm, and the air outlets 1.2 and 1.3 are separated from the knob channel or groove. At this time, rotate the knob with the center air outlet 1.1 as the rotation axis. In this way, the air outlet 1.1 is always aligned with the knob channel 3.1, that is, no matter in any state, there is always a channel open. In the default state, the two air outlets 1.2 and 1.3 next to it are aligned with the knob channels 3.2 and 3.3 respectively, and there are 3 air inlet channels at this time; after rotating the knob 3 90 degrees clockwise, the air outlet 1.2 is blocked due to its alignment with the groove 3.5, and the air outlet 1.3 is connected due to its alignment with the knob channel 3.2, and there are 2 channels at this time; after continuing to rotate in this direction for 90 degrees, the air outlet 1.2 is blocked due to its alignment with the groove 3.4, and the air outlet 1.3 is blocked due to its alignment with the groove 3.5, and there is only 1 channel at this time; rotate another 90 degrees, the air outlet 1.2 is connected due to its alignment with the knob channel 3.3, and the air outlet 1.3 is blocked due to its alignment with the groove 3.4; continue to rotate 90 degrees, and it has turned 360 degrees and returned to the default state, with 3 channels. It can be seen that the number of channels can be changed to 1, 2 and 3 by rotating the knob 3. Therefore, the number of channels for entering the gas can be changed relatively simply by rotating the knob 3. The air inlet cavity 1 and the knob 3 together constitute a variable channel.

[0020] The plasma-specific power supply used in the device has an output frequency of 5 to 30 kHz and an AC or pulse voltage of 5 to 10 kV. The external end of the high-voltage electrode 5 is connected to the positive electrode of the plasma discharge-specific power supply, and the internal end is connected to the positive copper plate 4.1 at the bottom of the gas mixing chamber 4, and is electrically connected to the plasma discharge needle tube 4.3. The ground electrode 10 is located at the lower left side of the plasma activation chamber 9, and the external end of the ground electrode 10 is connected to the negative electrode of the plasma-specific power supply, and the internal end is connected to the negative copper plate 9.1 at the bottom of the plasma activation chamber 9. When the plasma discharge power supply acts, a high-voltage electric field will be formed between the plasma discharge needle tube 4.3 and the negative copper plate 9.1.

[0021] Working principle: After changing the number of air inlet channels by rotating the knob, the gas can enter through the air inlet 2, and different gases are mixed in the gas mixing chamber 4, and then come out from the bottom of the plasma discharge needle tube. The excess gas can be discharged from the exhaust port 8, and water is added to the plasma activation chamber 9 from the water inlet 7. The plasma-specific power supply supplies power to the device. When the device is working, if the insulating plate 4.2 is not added, the high voltage between the plasma discharge needle tube 4.3 and the negative copper plate 9.1 will break down the gas discharged from the bottom of the needle tube, and this is spark discharge; after adding the insulating plate 4.2, there is an insulating medium between the plasma discharge needle tube 4.3 and the negative copper plate 9.1, and there are two discharge modes: dielectric barrier discharge and spark discharge, so it is plasma mixed discharge. The ionized gas will generate low-temperature plasma, which will form plasma-activated water after contacting with water. The generated plasma-activated water will enter the water outlet 13 at the bottom, and then be transmitted to the atomizer 11 through the rubber tube 12. The atomizer sheet 11.2 in the atomizer 11 will vibrate at a high frequency to turn the plasma-activated water into a spray and spray it onto the surface of fruits and vegetables.

[0022] The plasma discharge needle tube 4.3 is used to generate low-temperature plasma. The uniform length of the discharge tube and the equal spacing between the needle tubes ensure the uniformity of the discharge effect, thereby ensuring the uniformity of the plasma entering the plasma activation chamber 9. The discharge effect can be enhanced by changing the number of plasma discharge needle tubes 4.3, changing the discharge voltage and changing the flow rate of the working gas; the number of channels can be changed by rotating the knob 3 to change the type and amount of the incoming gas; the discharge mode can be changed by adding the insulating plate 4.2 to form a plasma mixed discharge; the range of plasma activated water atomization can be controlled by changing the size and vibration frequency of the ceramic atomizing plate 11.2.

[0023] Finally, it should be noted that although the present invention has been described through preferred embodiments, the present invention is not limited to the embodiments described herein, and also includes various changes and modifications made without departing from the scope of the present invention.

Claims

1. A variable channel plasma mixed discharge device, characterized in that: From top to bottom, they are the air inlet, air inlet cavity, knob, gas mixing cavity, high voltage electrode, plasma discharge needle tube, cavity cover, insulating plate, plasma activation cavity, ground electrode, water outlet, rubber tube, and atomizer. There are three air inlets, one located at the center of the air inlet cavity, and the other two are at the same distance from the center and form a right angle with the center line; the air inlet cavity is a solid quartz structure; the knob is made of solid quartz material, and has three knob channels and two grooves that pass through from top to bottom, one knob channel is located at the center of the knob, and the other two knob channels are at the same distance from the center and form a right angle with the center line, and when the center of the knob is taken as the symmetry center, the two grooves are respectively located at the symmetric positions of the two knob channels; the mixing cavity is a hollow quartz cavity with an opening at the top and 25 circular holes at the bottom, and a positive copper plate with 25 circular holes is placed at the bottom; the high-voltage The electrode is a copper rod and is connected to the positive copper plate; the plasma discharge needle tube is a hollow metal needle, the number is 25, arranged in five rows and five columns, and passes through the small hole at the bottom of the mixing chamber and the positive copper plate; the chamber cover is made of quartz material, has a water inlet and an exhaust port, and has a through hole in the center; the insulating plate is a solid quartz plate; the plasma activation chamber is a hollow quartz chamber with an opening on the top, and a negative copper plate is placed at the bottom; the grounding electrode is a copper rod and is connected to the negative copper plate; the water outlet is located at the lower right side of the plasma activation chamber; the atomizer is connected to the water outlet through the rubber tube.

2. A variable channel plasma mixed discharge device according to claim 1, characterized in that: The three air inlets all have an outer diameter of 30mm, an inner diameter of 20mm, and a height of 30mm; the diameter of the upper part of the air inlet cavity is 270mm, the height is 50mm, and the diameter of the lower part is 200mm, and the height is 20mm; the outer diameter of the upper part of the knob is 220mm, the inner diameter is 200mm, and the height is 50mm, and the outer diameter of the lower part is 200mm, the inner diameter is 180mm, and the height is 10mm.

3. The variable channel plasma mixed discharge device according to claim 1, characterized in that: The diameter of the high-voltage electrode is 5mm; the positive copper plate is 170mm long, 170mm wide and 5mm thick; the outer diameter of the upper half of the mixing chamber is 270mm, the height is 50mm, the diameter at the opening is 200mm, the thickness of the cavity is 10mm, the diameter of the lower half is 200mm, and the height is 15mm; the 25 plasma discharge needle tubes are of the same size, with an outer diameter of 8mm, an inner diameter of 6mm, a length of 135mm, and a mutual spacing of 20mm; the insulating plate has a diameter of 200mm and a thickness of 10mm.

4. The variable channel plasma mixed discharge device according to claim 1, characterized in that: The outer diameter of the upper part of the cavity cover is 400mm, and the height is 15mm. The outer diameter of the lower part is 380mm, and the height is 10mm. The diameter of the through hole at the center is 200mm. The outer diameters of the water inlet and the exhaust port are both 40mm, and the inner diameters are both 30mm. The diameter of the grounding electrode is 5mm. The negative copper plate is 260mm long, 260mm wide, and 5mm thick. The outer diameter of the plasma activation chamber is 400mm, the opening diameter is 380mm, the height is 180mm, and the cavity thickness is 10mm. The outer diameter of the water outlet is 40mm, and the inner diameter is 30mm.

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