Plasma jet activated water spray apparatus and method

Abstract

The application discloses a kind of plasma jet activated water spray device and method, spray device includes water tank, the output gas port of gas pump is connected total gas duct, total gas duct is divided into first gas duct and second gas duct by tee pipe, plasma jet generation module and first electromagnetic air valve are arranged in first gas duct, and plasma jet enters water tank by first gas duct;Second gas duct and liquid guide pipe are connected to the spray head of spray module, and spray is formed according to the pressure difference between gas and liquid, and the end of liquid guide pipe is immersed below the water surface of water tank.The plasma jet activated water and spray integrated structure coupling of the application improves the life of strong oxidizing active particles, and can control the generation of activated water spray and droplet size.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of plasma activated water, and relates to a plasma jet activated water spraying device and method. BACKGROUND

[0002] The treatment of water or water surface with low-temperature plasma can make the treated water solution (plasma activated water) have high chemical activity within a certain time, and the application effect is remarkable in many fields such as sterilization and disinfection, fruit and vegetable preservation, and instrument surface decontamination. Plasma activated water mist is an advanced form of plasma activated water. The plasma activated water is sprayed in the form of water mist, the acting surface area is larger, and the application range is further expanded.

[0003] Since the active substances in the plasma activated water will rapidly decay over time, the plasma activated water mist needs to meet the requirements of instant production and instant use. Based on the above premise, the plasma activated water mist device needs to consider the following two technical requirements: 1. High-efficiency gas-liquid mass transfer of active particles in the process of plasma activated water solution, especially the short life of strong oxidizing active particles (such as OH, NO, etc.), the plasma needs to be in constant contact with the liquid surface; 2. Integrated structural design of the plasma activated water spraying process, coupling the plasma activated water process and the atomization process structure, and collaborative control to reduce the complexity of the device used by the liquid pump and the gas pump together. However, the existing plasma activated water spraying device cannot meet the above two technical requirements, and the treatment process and application effect are not good.

[0004] Therefore, the present application provides a plasma jet activated water spraying device and method, which utilizes a single gas pump and the collaborative control of gas flow rate to realize the generation and adjustment of plasma activated water mist. SUMMARY

[0005] In order to solve the above problems, the present application provides a plasma jet activated water spraying device, which integrates the plasma jet activated water and the spraying structure, improves the life of strong oxidizing active particles, and can control the generation of activated water mist and the size of droplets, solving the problems in the prior art.

[0006] Another object of the present application is to provide a method for using the plasma jet activated water spraying device.

[0007] The technical scheme adopted by the present application is a kind of plasma jet activated water spray device, including water tank, the output gas port of gas pump is connected with total gas guide pipe, total gas guide pipe is divided into first gas guide pipe and second gas guide pipe by three-way pipe, plasma jet generation module and first electromagnetic air valve are arranged in first gas guide pipe, and plasma jet enters water tank through first gas guide pipe;Second gas guide pipe and liquid guide pipe are connected with the spray head of spray module, and spray is formed according to the pressure difference between gas and liquid, and the end of liquid guide pipe is immersed below the water surface of water tank.

[0008] Further, a water level sensor is arranged in the water tank to detect the liquid level of the water tank and transmit data to the control module;The control module is signal connected with the control end of the gas pump and the first electromagnetic air valve, and the control module controls the gas flow rate of the first gas guide pipe by the output gas flow of the first electromagnetic air valve and the gas pump according to the change of the distance H between the plasma jet nozzle and the liquid surface in the water tank, and the gas flow rate of the second gas guide pipe is constant, so that the plasma jet is always in contact with the liquid surface.

[0009] Further, a gas pressure sensor is installed in the water tank to detect the gas pressure in the water tank and transmit data to the control module;The control module is signal connected with the control end of the second electromagnetic air valve, and the control module changes the gas pressure in the water tank by controlling the second electromagnetic air valve, thereby changing the liquid flow rate in the liquid guide pipe, and further controlling the size of the plasma activated water spray droplets.

[0010] Further, the spray module includes a rear cover, the rear cover is threadedly connected with the front cover, and a cavity is formed between the front cover and the rear cover to form an air chamber;The center of the front cover is provided with an atomizing nozzle, and the atomizing nozzle is communicated with the air chamber;The rear cover is provided with a water inlet and an air inlet, the tail of the air inlet is connected with the second gas guide pipe, and the head of the air inlet is communicated with the air chamber;The water inlet is located in the center of the rear cover, the tail of the water inlet is connected with the liquid guide pipe, the head of the water inlet is connected with a water injection needle, the water injection needle is communicated with the air chamber, and the water injection needle and the atomizing nozzle form a venturi jet pipe structure.

[0011] Further, a spiral guide groove is arranged near the atomizing nozzle on the inner wall of the air chamber, and a gap of 0.1-0.3mm exists between the water injection needle and the spiral guide groove, so that the water flow sprayed by the water injection needle generates centrifugal force through the spiral guide groove, thereby spreading at the atomizing nozzle and increasing the coverage range.

[0012] Further, the axial length of the spiral guide groove is 2mm-3mm, and the spiral angle is 30°-60°.

[0013] Further, the diameter of the water injection needle is 0.7-0.9mm, and the length is 19mm-20mm.

[0014] Further, the plasma jet generating module is a dielectric barrier discharge jet structure, comprising a high-voltage electrode, a barrier medium and a ground electrode, the barrier medium and the ground electrode are closely attached, the head of the barrier medium is connected with the first air guide pipe, the plasma jet is sprayed from top to bottom and can contact the water surface; the ground electrode is a conductive metal ring and can be sleeved outside the barrier medium; the high-voltage electrode is a spiral spring-shaped iron wire and is placed inside the barrier medium, the tail of the high-voltage electrode is connected with the plasma power supply; the first electromagnetic air valve is installed on the tail branch of the barrier medium.

[0015] Further, the model of the single-chip microcomputer in the control module is STM32F103C8T6.

[0016] A use method of the plasma jet activated water spraying device, comprising two modes of spraying and air blowing, which can be selected through an interaction module.

[0017] When the mode is spraying, the control module ensures that the first electromagnetic air valve is opened, and through the liquid level information transmitted by the water level sensor, the first electromagnetic air valve and the air pump are cooperatively controlled, so that the plasma jet is always in contact with the liquid surface, the plasma is fully combined with the water, and the plasma activated water is generated; the second electromagnetic air valve is adjusted through the water tank internal air pressure information transmitted by the air pressure sensor, so that the droplet diameter of the plasma activated water mist is adjusted.

[0018] When the mode is air blowing, the control module controls the first electromagnetic air valve and the second electromagnetic air valve to be completely opened, at this time, the airflow is directly sprayed out from the second electromagnetic air valve through the water tank, at this time, the water level sensor and the air pressure sensor do not work.

[0019] The beneficial effects of the present application are:

[0020] 1. The plasma jet activated water solution process and the spraying process are cooperatively controlled, only a single air pump is used to meet the gas flow rate control of the two groups of air paths, the generation of the plasma jet and the activated water process are realized, and the generation and adjustment of the spraying are realized.

[0021] 2. In the plasma jet activated water solution process, the length of the plasma jet and the liquid surface height are synchronously changed through a feedback control loop, the plasma jet plume can always contact the liquid surface, the plasma active particles, especially the short-life active particles, can stably and efficiently realize gas-liquid mass transfer.

[0022] 3. The air path and the water path constitute a Venturi tube type structure in the spray head, through the cooperative control of the air path and the water path, the control of the spraying injection distance and the droplet diameter can be realized, and the application requirements of different scenes and different types of the plasma activated spraying are met.

[0023] 4. The integrated structural design and coordinated control of the plasma jet activation water process and spray of this invention enable the instant generation and use of plasma-activated water, resulting in high processing efficiency, strong aqueous solution activity, and safe and convenient operation. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of the internal structure of an embodiment of the present invention.

[0027] Figure 3 This is a schematic diagram of the nozzle structure in an embodiment of the present invention.

[0028] Figure 4 This is a schematic diagram of the plasma jet module structure in an embodiment of the present invention.

[0029] Figure 5 This is a schematic diagram of the air and water flow directions according to an embodiment of the present invention.

[0030] Figure 6 This is a fitting curve of the gas flow rate of the first gas guide tube and the change in plasma jet length in an embodiment of the present invention.

[0031] In the diagram: 1. T-connector; 2. Main air duct; 3. Control module; 4. Air pump; 5. Water tank; 6. Liquid duct; 7. Nozzle; 8. First solenoid valve; 9. Plasma jet generating module; 10. Water level sensor; 11. Second solenoid valve; 12. Air pressure sensor; 13. Air inlet; 14. Water inlet; 15. Rear cover; 16. O-ring seal; 17. Front cover; 18. Water jet needle; 19. Air chamber; 20. Atomizing nozzle; 21. Spiral guide groove; 22. Barrier medium; 23. Plasma power supply chamber; 24. High-voltage electrode; 25. Ground electrode. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0033] Example 1,

[0034] A plasma jet activated water spray device that can be used for disinfection, such as Figures 1-2 As shown, the plasma jet generating module 9 and the first electromagnetic valve 8 are disposed inside the first gas guide pipe, and the plasma jet enters the water tank 5 through the first gas guide pipe; the first electromagnetic valve 8 is used to control the gas flow rate of the plasma jet to ensure that the plasma jet can be in constant contact with the liquid surface; the second electromagnetic valve 11 is disposed at the gas outlet of the water tank 5 to control the gas pressure inside the water tank 5; the second gas guide pipe and the liquid guide pipe 6 are both connected to the nozzle of the spray module, and a spray is formed according to the pressure difference between the gas and the liquid.

[0035] As the spray causes the liquid level to drop, a water level sensor 10 is installed inside the water tank 5 to detect the liquid level height and transmit the data to the control module 3. The water level sensor 10 is a Water Sensor that uses a transistor to convert the water level into a current signal, which is then acquired by the microcontroller. Based on the change in the distance H between the plasma jet nozzle and the liquid surface, the control module 3 coordinates the output gas flow rate of the first electromagnetic valve 8 and the air pump 4 to change the gas velocity of the plasma jet, ensuring that the plasma jet can maintain constant contact with the liquid surface.

[0036] Since the gas velocity in the second gas delivery tube is constant (20 m / s) and the radius of the second gas delivery tube is 0.002 m, the calculated gas flow rate Q2 in the second gas delivery tube is 0.0002512 m³ / s. 3 / s (15L / min), since the gas output from the air pump 4 enters both the first and second air guide pipes, the flow rates of the first and second air guide pipes and the gas output from the air pump 4 satisfy equation (1):

[0037] Q 气 =Q1+Q2 (1)

[0038] Among them, Q 气 Q1 is the output air flow rate of air pump 4, and Q1 is the gas flow rate of the first air guide pipe.

[0039] Meanwhile, the relationship between the gas flow rate Q1 and the gas velocity V1 in the first gas guide tube is shown in equation (2):

[0040] Q1=V1×S1 (2)

[0041] S1 represents the cross-sectional area of ​​the first air guide tube, which can be adjusted by the first solenoid valve 8.

[0042] Based on equations (1) and (2), we obtain equation (3):

[0043] Q 气 =V1×S1+Q2 (3)

[0044] The first solenoid valve 8 can control S1 at 0.00011304m 2 -0.00001256m 2 The flow rate varies between these parameters, but due to the high precision requirements, coordinated control of the gas flow rate of the four air pumps is necessary.

[0045] The plasma jet length H and the gas flow rate Q1 in the first gas guide tube are directly related, and the experimental results are shown in Table 1.

[0046] Table 1. Variation of plasma jet length with gas flow rate in the first gas guide tube.

[0047] First gas tube gas flow (L / min) Plasma jet length (cm) 1 20 2.5 33 5 40 7.5 48 10 53 12.5 55 15 55

[0048] As shown in Table 1, with the increase of gas flow rate in the first gas delivery tube, the plasma jet length gradually increases, while the growth rate of the plasma jet length continuously decreases, remaining constant after reaching 12.5 L / min. The data fitting results are shown in [reference needed]. Figure 6 The fitting formula is shown in formula (4):

[0049] H=(69.44×Q1+33.88) / (Q1+4.07) (4)

[0050] The independent variable is the gas flow rate Q1 in the first gas guide tube, and the dependent variable is the plasma jet length H.

[0051] After testing, the data shown in Table 2 showed better control results.

[0052] Table 2 Relationship between gas flow rate in the first gas inlet tube and gas flow rate in the gas pump

[0053] First gas tube gas flow (L / min) Air pump gas flow (L / min) 0-2.5 16 2.5-7.5 21 7.5-12.5 26

[0054] The water level information is obtained by the water level sensor 10, and then the required plasma jet length can be obtained. The gas flow rate Q1 of the first gas guide tube is obtained according to equation (4). The opening degree of the first electromagnetic valve 8 is determined according to the gas flow rate Q1 of the first gas guide tube, and then the gas flow rate of the first gas guide tube is controlled so that the plasma jet can be in constant contact with the liquid surface. At the same time, the speed of the air pump 4 is controlled by PWM (pulse width modulation) according to Table 2, and the gas flow rate of the air pump 4 is controlled, thereby improving the control accuracy.

[0055] The direct influencing factor on the size of the spray droplets is the liquid flow rate of the spray needle 18 (i.e., the liquid flow rate within the liquid guide tube 6), and Table 3 shows the experimental test results. In reality, it is also related to the gas flow rate of the second air guide tube. Changes in gas flow rate make the droplet formation process very complex, which is not conducive to control. In this embodiment of the invention, to achieve better control of the droplet diameter, the gas flow rate of the second air guide tube is fixed. The pressure sensor 12 is installed on the inner wall of the water tank 5 to detect the internal pressure of the water tank 5 and transmit the data to the control module 3. The control module 3 controls the second electromagnetic valve 11 to change the gas pressure inside the water tank 5, thereby changing the liquid flow rate within the liquid guide tube 6, and thus controlling the size of the plasma-activated water spray droplets. The pressure sensor 12 is an RSC pressure sensor, which can provide real-time feedback on the internal pressure of the water tank 5.

[0056] Control module 3 is connected to water level sensor 10, air pressure sensor 12, first solenoid valve 8, and second solenoid valve 11. Control module 3 is also connected to the main air pipe 2 and air pump 4. The main air pipe 2 is divided into a first air pipe and a second air pipe via a three-way pipe 1. Due to the presence of the first solenoid valve 8, without air pump 4, the gas flow rate between the first and second air pipes would exhibit a coupling relationship where one pipe has a higher flow rate than the other, which is detrimental to spray generation. By controlling the flow rate of air pump 4 through control module 3, the gas flow rate in the second air pipe remains constant while the gas flow rate in the first air pipe continuously increases. This avoids affecting the spray effect as the plasma jet plume length increases. In other words, while ensuring a constant gas flow rate in the second air pipe, the total flow rate of air pump 4 is controlled according to the flow rate requirements of the first air pipe.

[0057] Control module 3 ensures a constant gas flow rate in the second gas guide pipe, maintains constant plasma jet contact with the liquid surface by adjusting the flow rate in the first gas guide pipe, and changes the liquid flow rate in the liquid guide pipe 6 by altering the gas pressure within the water tank 5, thereby controlling the generation and droplet size of the plasma-activated water spray. In summary, the microcontroller control system receives the electrical signal from the water level sensor 10, calculates the remaining liquid level, and, in conjunction with the structure of the water tank 5, controls the current flowing through the first solenoid valve 8 and the second solenoid valve 11 to achieve control over the physical characteristics of the system's gas and water circuits.

[0058] Water tank 5 has a cylindrical structure with four interfaces for connecting to the outside world, including a water tank inlet, a water tank air inlet, a water outlet, and a pressure relief port. These four interfaces are evenly distributed on the upper part of water tank 5. Figure 1 (Water inlet of the middle water tank is not shown); the water inlet of the water tank is threaded, and can be sealed with an external threaded plug after water filling; the air inlet of the water tank is connected to the first air guide pipe; the pressure relief port is connected to the second solenoid valve 11; the water outlet is connected to the liquid guide pipe 6, and the tail of the liquid guide pipe 6 is always submerged in water.

[0059] Example 2,

[0060] like Figure 3 As shown, the spray module includes a nozzle water inlet 14, an air inlet 13, an atomizing nozzle 20, a water spray needle 18, a front cover 17, and a rear cover 15. The rear cover 15 and the front cover 17 are threaded together and sealed with an O-ring 16, forming a cavity area that creates an air chamber 19, through which gas and water can pass. The water inlet 14, air inlet 13, and water spray needle 18 are all located on the rear cover 15, while the atomizing nozzle 20 is located on the front cover 17. The water inlet 14 is located at the center of the rear cover 15, with its tail connected to a liquid guide tube 6 and its head connected to the water spray needle 18. The air inlet 13 is located in the upper middle part of the rear cover 15, adjacent to the water inlet 14, but the air inlet 13 and the water inlet 14 are not connected. The water spray needle 18 is located in the cavity between the front cover 17 and the rear cover 15 (i.e., the air chamber 19), with its head near the atomizing nozzle 20. The air chamber 19 communicates with the outside world through the atomizing nozzle 20. The water spray needle 18 and the atomizing nozzle 20 work together to form a Venturi-like jet tube structure. By utilizing the changes in gas velocity and pressure, the water is dispersed under the impact of the high-speed airflow. On the other hand, due to the extreme pressure change from the nozzle outward, the water is further torn apart by the air pressure to form droplets. The atomizing nozzle 20 is located in the middle of the front cover 17 and adopts a spiral guidance method. When the liquid and gas are mixed and sprayed out in the air chamber, the spiral guide groove 21 will further tear apart large droplets, thereby ensuring the good atomization characteristics of this nozzle.

[0061] The outer wall of the atomizing nozzle 20 is conical, and the inner wall of the air chamber 19 is provided with a spiral guide groove 21 near the atomizing nozzle 20. The water spray needle 18 is located in the center of the atomizing nozzle 20, with a gap (0.1-0.3mm) between it and the spiral guide groove 21, allowing airflow to pass through and forming a Venturi-like structure. Due to the small gap, the gas flows through at a very high velocity, thus creating a low-pressure area. On the one hand, water can be sprayed using the negative pressure water spray needle 18; on the other hand, under the action of pressure, the water will be further atomized, improving the atomization effect. The spiral guide groove 21 mainly plays an auxiliary role, allowing the water flow sprayed by the water spray needle 18 to pass through the spiral guide groove 21, thereby generating a certain centrifugal force. After the water flow exits the nozzle, it is dispersed under the action of centrifugal force, which can increase the coverage of the water mist and improve the atomization effect. The axial length of the spiral guide groove 21 is 2mm-3mm, and the spiral angle is 30°-60°.

[0062] The diameter of the water jet needle 18 is 0.7-0.9 mm, and the length is 19-20 mm. If the diameter is too small, the gap will be too large, the Venturi effect will be weakened, the negative pressure effect on the water flow will be weakened, and the atomization effect will be poor. If the diameter is too large, the gap will be too small, the air jet volume will be reduced, and the effect of the airflow on the liquid (including shearing, impact, etc.) will be weakened. Specific experiments are shown in Table 3. If the length of the water jet needle 18 is too short or too long, the Venturi structure will not be formed or the effect will be weakened. The length should be exactly where the gas flow rate is the fastest.

[0063] Table 3 Relationship between spray needle diameter and atomization effect

[0064] Water jet needle diameter (mm) Atomization effect 0.6 Water jet diameter is large, atomization effect is weak 0.7-0.9 Atomization effect is ideal 1.0 Water jet diameter is large, atomization effect is weak

[0065] In this embodiment of the invention, considering the compact structure, the air chamber 19 is directly constructed using the front cover 17 and the rear cover 15. The air chamber 19 mainly serves to guide the airflow to be sprayed evenly from the atomizing nozzle. Because the nozzle design causes the gas to enter the nozzle from one side, a buffer area (air chamber 19) needs to be set up. After the gas is filled with the air chamber 19, it can be sprayed evenly from the atomizing nozzle 20 to achieve the best atomization effect.

[0066] In this embodiment of the invention, the structural design of the air path and water path and the Venturi tube structure of the nozzle are highly coupled. First, this embodiment of the invention does not use the air chamber section design of the traditional nozzle. Instead, the air chamber 19 is directly constructed using the front cover 17 and the rear cover 15, making the entire structure more compact. Then, by utilizing the formed Venturi structure, no additional structure is added, avoiding an overly complex structure. The spiral guide groove 21 is embedded in the inner wall of the air chamber 19, which assists in atomization and expands the spray range without interfering with the normal operation of other structures.

[0067] Example 3,

[0068] Plasma jet generating module 9 is a dielectric barrier discharge jet structure, such as Figure 4 As shown, the device includes a high-voltage electrode 24, a barrier medium (quartz tube) 22, and a ground electrode 25. The barrier medium 22 and the ground electrode 25 are tightly fitted together. The head of the barrier medium 22 is connected to the first gas guide tube, and the plasma jet is sprayed from top to bottom, allowing it to contact the water surface. The ground electrode 25 is a copper ring that can be fitted over the barrier medium 22. The high-voltage electrode 24 is a helical spring-shaped iron wire placed inside the barrier medium 22, and its tail is connected to the plasma power source. A first electromagnetic valve 8 is installed on the branch at the tail of the barrier medium 22. A gas pump 4 is placed above the device and connected to the control module 3. The control module 3 can control the gas flow rate, allowing the gas to flow stably and at high speed through the high-voltage electrode 24.

[0069] The plasma power supply applies a 3000V voltage to the high-voltage electrode 24. After being energized, the air between the high-voltage electrode 24 and the blocking medium 22 is ionized, generating diffuse plasma. At this time, the air pump 4 is energized, which can generate a stable plasma jet plume. The air flow rate can be controlled by controlling the first electromagnetic air valve 8, thereby controlling the length of the plasma jet plume.

[0070] When plasma is generated by the device, the plasma jet plume contacts the water surface, bringing active substances from the air into the water. At the same time, the water level sensor 10 receives the liquid level height signal and controls the opening and closing degree of the first electromagnetic valve 8 through the control module 3, so that the jet plume can be lengthened as the liquid level drops, maintaining high efficiency in generating plasma-activated water.

[0071] Example 4,

[0072] Control module 3 includes a microcontroller control system and multiple GPIO ports. The microcontroller is an STM32F103C8T6. The multiple GPIO ports are connected to the water level sensor 10, the air pressure sensor 12, the first solenoid valve 8, and the second solenoid valve 11, respectively. The microcontroller control system receives the electrical signal from the water level sensor 10, calculates the current remaining liquid level, and controls the flow current of the first solenoid valve 8 and the second solenoid valve 11 to control the physical characteristics of the system's air and water circuits.

[0073] This invention enables two spraying modes: mist and jet, selectable via an interactive module. In mist mode, the control module 3 ensures the first electromagnetic valve 8 is open and coordinates with the water level sensor 10 to control both the first electromagnetic valve 8 and the air pump 4, ensuring the plasma plume continuously spreads across the liquid surface and fully integrates with the water to generate plasma-activated water. The second electromagnetic valve 11 is adjusted based on the internal air pressure information from the pressure sensor 12, thus regulating the droplet diameter of the plasma-activated water mist.

[0074] When the jet mode is activated, the control module 3 controls the first solenoid valve 8 and the second solenoid valve 11 to be fully opened. At this time, the airflow passes through the water tank 5 and is directly ejected from the second solenoid valve 11. At this time, the water level sensor 10 and the air pressure sensor 12 are not working. The jet mode can directly eject plasma gas and is applicable to scenarios where water cannot be touched, such as disinfection of electronic equipment and fabrics. This mode can expand the application range of this device and provide users with more options.

[0075] The working process of this invention embodiment:

[0076] like Figure 5As shown, when disinfection of the human body or environment is required, the device is first activated via the interactive screen, and the droplet diameter of the plasma-activated water mist is selected. The plasma power supply is activated, transmitting high voltage to the high-voltage electrode 24 of the dielectric barrier discharge structure, thereby generating a large amount of plasma in the cavity region between the high-voltage electrode 24 and the barrier dielectric 22. At this time, the air pump 4 starts, and the high-speed airflow is split into two paths through the three-way pipe 1. One path enters the air inlet 13 of the nozzle through the second air guide pipe, and the other path enters the plasma jet generation module 9 through the first air guide pipe. The high-speed airflow generates a plasma jet as it passes through the discharge region, causing the ejected gas to carry plasma, i.e., a plasma jet plume. The control module 3 reads the value of the water level sensor 10 and then controls the air volume of the first electromagnetic valve 8, ensuring that the plasma jet plume is constantly in contact with the water surface. Simultaneously, the control module 3 activates the second electromagnetic valve 11 according to the user-selected mode. The air pressure sensor 12 in the water tank 5 reads the air pressure value and returns it to the control module 3. The control module 3 adjusts the second electromagnetic valve 11 according to the air pressure threshold to control the air pressure in the water tank 5. The plasma-activated water in the water tank 5 is driven by airflow and enters the nozzle water path through the liquid guide pipe 6. The air pressure control of the control module 3 can adjust the droplet diameter of the plasma-activated water mist.

[0077] Water flows into the inlet 14 at the nozzle and then sprays out from the spray needle 18. At this time, a high-speed airflow enters from the air inlet 13, passes through the air chamber 19, and is sprayed out from the slit between the spray needle 18 and the atomizing nozzle 20. At this time, the liquid sprayed out by the spray needle 18 is torn into small droplets by the high-speed gas and air pressure, achieving the atomization effect.

[0078] In the structure of this embodiment of the invention, the gas flow velocity in the second gas guide tube is fixed at 20 m / s, and the diameter of the plasma-activated water mist droplets varies with the liquid flow velocity in the liquid guide tube 6, as shown in Table 4:

[0079] Table 4. Variation of plasma-activated water mist droplet diameter with liquid flow rate in the guide tube.

[0080] Serial number Liquid flow rate m / s Liquid droplet diameter mm Spray distance cm 1 1.5 0.01-0.05 80 2 3 0.05-0.3 95 3 4 0.3-0.8 110 4 5 0.8-1.5 120

[0081] As shown in Table 4, the spray distance and droplet diameter of the present invention are both controllable, which can meet the different usage needs of different scenarios. When a small-scale fine spray is required, a low liquid flow rate is used, and when a large-scale spray is required, a high liquid flow rate is used. The liquid flow rate in Table 4 is the flow rate in the water spray needle 18.

[0082] Traditional plasma water spray formation requires first activating water through plasma jet discharge, and then spraying it out through a nozzle. This process takes time, and the active ingredients in the plasma-activated water are easily deactivated, resulting in a low concentration of active ingredients in the final droplets (100-120 μM / L). This invention, through control of the plasma jet-activated aqueous solution re-spraying process and coordinated control of the gas and water paths, achieves plasma jet-contact activation of the aqueous solution, efficient atomization of the aqueous solution, and controllable droplet size spraying. From preparation to spray formation, the process is integrated, and the distance between the jet plume and the water surface is stable, ensuring a stable active ingredient concentration of 230-300 μM / L, which does not decrease as the water surface level decreases.

[0083] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A plasma jet activated water spray device, comprising a water tank (5), characterized in that, The output gas port of the air pump (4) is connected to the main air pipe (2). The main air pipe (2) is divided into a first air pipe and a second air pipe through a three-way pipe (1). The plasma jet generating module (9) and the first electromagnetic valve (8) are located in the first air pipe. The plasma jet enters the water tank (5) through the first air pipe. The second air pipe and the liquid pipe (6) are both connected to the nozzle of the spray module. The spray is formed according to the pressure difference between the gas and the liquid. The end of the liquid guide tube (6) is immersed in Below the water surface of water tank (5); The water tank (5) is equipped with a water level sensor (10) to detect the liquid level height of the water tank (5) and transmit the data to the control module (3). The control module (3) is connected to the control terminal signal of the air pump (4) and the first electromagnetic valve (8). The control module (3) controls the gas flow rate of the first gas guide tube in coordination with the output gas flow rate of the first electromagnetic valve (8) and the air pump (4) according to the change of the distance H between the plasma jet nozzle and the liquid surface inside the water tank (5). The gas flow rate of the second gas guide tube is constant, so that the plasma jet is constantly in contact with the liquid surface. The water tank (5) is equipped with a pressure sensor (12) to detect the internal pressure of the water tank (5) and transmit the data to the control module (3). The control module (3) is connected to the control terminal of the second electromagnetic valve (11). The control module (3) changes the gas pressure in the water tank (5) by controlling the second electromagnetic valve (11), thereby changing the liquid flow rate in the liquid guide pipe (6) and controlling the size of the plasma activated water spray droplets.

2. The plasma jet activated water spray device according to claim 1, characterized in that, The spray module includes a rear cover (15), which is threaded to the front cover (17). There is a cavity between the front cover (17) and the rear cover (15) to form an air chamber (19). The center of the front cover (17) is provided with an atomizing nozzle (20), which is connected to the air chamber (19). The rear cover (15) is provided with a water inlet (14) and an air inlet (13). The tail of the air inlet (13) is connected to a second air guide pipe, and the head of the air inlet (13) is connected to the air chamber (19). The water inlet (14) is located at the center of the rear cover (15). The tail of the water inlet (14) is connected to a liquid guide pipe (6), and the head of the water inlet (14) is connected to a water spray needle (18). The water spray needle (18) is connected to the air chamber (19), and the water spray needle (18) and the atomizing nozzle (20) form a Venturi jet tube structure.

3. The plasma jet activated water spray device according to claim 2, characterized in that, The inner wall of the air chamber (19) is provided with a spiral guide groove (21) near the atomizing nozzle (20). There is a gap of 0.1-0.3mm between the water spray needle (18) and the spiral guide groove (21). The water flow sprayed by the water spray needle (18) generates centrifugal force through the spiral guide groove (21), thereby spreading out at the atomizing nozzle (20) and increasing the coverage area.

4. The plasma jet activated water spray device according to claim 3, characterized in that, The axial length of the spiral guide groove (21) is 2mm-3mm, and the spiral angle is 30°-60°.

5. The plasma jet activated water spray device according to claim 3, characterized in that, The water spray needle (18) has a diameter of 0.7-0.9 mm and a length of 19-20 mm.

6. The plasma jet activated water spray device according to claim 1, characterized in that, The plasma jet generating module (9) is a dielectric barrier discharge jet structure, including a high-voltage electrode (24), a barrier medium (22) and a ground electrode (25). The barrier medium (22) and the ground electrode (25) are tightly attached. The head of the barrier medium (22) is connected to the first gas guide tube. The plasma jet is sprayed from top to bottom and can contact the water surface. The ground electrode (25) is a conductive metal ring that can be fitted outside the barrier medium (22). The high-voltage electrode (24) is a spiral spring-shaped iron wire placed inside the barrier medium (22). The tail of the high-voltage electrode (24) is connected to the plasma power supply. The first electromagnetic valve (8) is installed on the branch at the tail of the barrier medium (22).

7. The plasma jet activated water spray device according to claim 1, characterized in that, The microcontroller in the control module (3) is an STM32F103C8T6.

8. The method of using the plasma jet activated water spray device as described in claim 1, characterized in that, It includes two modes: spray and jet, which can be selected through the interactive module; When the mode is spray, the control module (3) ensures that the first electromagnetic valve (8) is open, and controls the first electromagnetic valve (8) and the air pump (4) in coordination with the liquid level information transmitted by the water level sensor (10), so that the plasma jet is constantly in contact with the liquid surface, ensuring that the plasma is fully integrated with the water phase and generating plasma-activated water; the second electromagnetic valve (11) is adjusted by the air pressure information inside the water tank (5) transmitted by the air pressure sensor (12), thereby adjusting the droplet diameter of the plasma-activated water mist; When the mode is jet, the control module (3) controls the first solenoid valve (8) and the second solenoid valve (11) to be fully opened. At this time, the airflow passes through the water tank (5) and is directly ejected from the second solenoid valve (11). At this time, the water level sensor (10) and the air pressure sensor (12) are not working.

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