CN114845459A

CN114845459A - Magnetic field enhanced plasma jet generating device

Info

Publication number: CN114845459A
Application number: CN202210580533.6A
Authority: CN
Inventors: 卢新培; 晋绍珲; 聂兰兰
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 2022-05-25
Filing date: 2022-05-25
Publication date: 2022-08-02

Abstract

The invention discloses a generating device of magnetic field enhanced plasma jet, belonging to the field of low-temperature plasma, comprising: the plasma jet generating unit is used for generating plasma jet and outputting the plasma jet through a gas output pipeline of the plasma jet generating unit; the annular magnet is arranged on the outer side of the gas output pipeline in a surrounding mode and used for generating a magnetic field in the gas output pipeline, and the direction of the Lorentz force provided by the magnetic field for the plasma jet is consistent with the flowing direction of the plasma jet so as to accelerate the flowing speed of the plasma jet. The plasma jet flow device solves the problems of short jet flow length, uneven discharge and low active component concentration of the existing plasma, ensures the dispersion and spatial distribution uniformity of the plasma, enhances the concentration of active oxides in the plasma, improves the contact efficiency of products and treated objects in application, and further improves the working efficiency of the whole device.

Description

Magnetic field enhanced plasma jet generating device

Technical Field

The invention belongs to the field of low-temperature plasma, and particularly relates to a magnetic field enhanced plasma jet generating device.

Background

The atmospheric pressure low-temperature plasma jet is usually an ionization wave formed by breakdown in a gas channel, is not limited by a narrow air gap space because the ionization wave occurs in an open space, and has huge application potential in the fields of biomedicine, surface modification, nanotechnology and the like because a particle set consisting of electrons, ions, neutral particles and various active free radicals. Dielectric barrier discharge is a common way of generating plasma jet, and is widely used because it can generate large area uniform plasma in a small gas gap. In order to improve the working efficiency of the plasma jet, on one hand, the development of the plasma jet of the dispersion discharge similar to Thomson or glow under the low-pressure condition is focused, and the plasma jet with longer size and larger area can be obtained while the discharge is dispersed; on the other hand, since the plasma jet generated during the gas gap ionization process contains a large amount of active substances, which are main components playing roles in application, and the active substances contain many components with short lifetime and low concentration, it is generally considered that the enhancement of the ionization intensity can effectively increase the concentration of the active components, and this behavior plays a crucial role in plasma biomedical application.

In various application fields, helium is often used as a medium to block the working gas of plasma jet. However, helium is expensive and difficult to maintain for large scale applications, and the desire to obtain high concentrations of active oxide requires the incorporation of some oxygen into the helium. If cheap argon is used as the working gas, the discharge channel is very easy to shrink under normal pressure, and the discharge is in a filament mode, and similarly, oxygen needs to be doped to increase the concentration of the active oxide at some time. In recent years, air is more desirable as the working gas, but due to the high breakdown field strength of air, the jet is difficult to be ejected like a helium-argon dielectric barrier jet.

Patent CN112004304A promotes the uniformity of radial space electric field and reduces the breakdown voltage through the combination of corona discharge and dielectric barrier discharge which can be independently regulated. Patent CN101466194A adopts a needle electrode and an annular high voltage electrode, the needle electrode discharge provides seed electrons for the annular electrode discharge, and a stable glow discharge plasma jet is formed between the annular electrode and the grounding electrode, but the same high voltage is applied to the needle electrode and the annular electrode of the device, and the voltage of the needle electrode and the voltage of the annular electrode cannot be independently adjusted, so that the electric field configuration in the space of the discharge area is fixed, which is not favorable for forming uniform large-area plasma. Patent CN109587921A utilizes impact ionization of high-energy electrons to generate uniform plasma with large area, and the energy of electrons can be adjusted and controlled, but its device structure is complex and cost is high. The existing plasma jet flow can not improve the ionization strength, simultaneously can perform stable dispersion discharge and obtain high-concentration active components, and the obtained jet flow length has obvious difference due to different breakdown voltages required by different working gases. This is a problem that is to be solved in various fields of application of the current plasma.

Disclosure of Invention

Aiming at the defects and improvement requirements of the prior art, the invention provides a magnetic field enhanced plasma jet generating device, and aims to solve the problems of short length, nonuniform discharge and low active ingredient concentration of the conventional plasma jet.

In order to achieve the above object, the present invention provides a magnetic field enhanced plasma jet generating device, comprising: the plasma jet generating unit is used for generating plasma jet and outputting the plasma jet through a gas output pipeline of the plasma jet generating unit; the annular magnet is arranged on the outer side of the gas output pipeline in a surrounding mode and used for generating a magnetic field in the gas output pipeline, and the direction of the Lorentz force provided by the plasma jet flow by the magnetic field is consistent with the flowing direction of the plasma jet flow, so that the flowing speed of the plasma jet flow is accelerated.

Still further, the plasma jet generating unit includes: the electrode structure comprises a first medium pipe, a first electrode, a second electrode, a high-voltage power supply and an air source, wherein the air source is communicated with the first medium pipe; the first electrode is inserted into the first medium pipe through one end of the first medium pipe and is coaxial with the first medium pipe, and a gas pipeline is formed between the first electrode and the first medium pipe; the other end of the first medium pipe is opened and serves as a gas output port of the gas pipeline; a part of the gas pipe on the gas output side serves as the gas output pipe; the second electrode is arranged around the outer wall of the first medium pipe at the gas output pipeline, and the annular magnet is arranged around the outer side of the second electrode; the first electrode and the second electrode are respectively connected with the high-voltage power supply and the ground, or the first electrode and the second electrode are respectively connected with the ground and the high-voltage power supply.

Still further, the plasma jet generating unit further includes: and the flow controller is connected between the gas source and the first medium pipe and is used for controlling the flow of the gas input into the first medium pipe from the gas source.

Furthermore, the high-voltage power supply is an alternating-current power supply or a high-voltage pulse power supply, and the discharge between the first electrode and the second electrode is adjusted by controlling the voltage of the high-voltage power supply.

Further, the first electrode is a tapered electrode with a smooth surface or a tapered electrode with a spiral structure arranged on the surface.

Further, the first electrode is a solid rod-shaped cylindrical electrode or a solid rod-shaped needle electrode, and the plasma jet generating unit further includes: and the second medium pipe is coaxially attached to the first electrode.

Furthermore, the first medium pipe and the second medium pipe are made of quartz glass or ceramic.

Further, when the first electrode is a solid rod-shaped needle electrode, the second electrode is a preset distance away from the end of the solid rod-shaped needle electrode with the smaller diameter.

Generally, by the above technical solution conceived by the present invention, the following beneficial effects can be obtained:

(1) the annular magnet is arranged on the outer side of the gas output pipeline of the plasma jet generation unit in a surrounding mode, the direction of a magnetic field generated by the annular magnet is orthogonal to the direction of a discharge electric field, left-hand rule is met, Lorentz force acting on charged particles in plasma jet is consistent with the direction of an air flow driving force, the flowing speed of the plasma jet is accelerated, the problems that the existing plasma jet is short in length, uneven in discharge and low in active ingredient concentration are solved, the dispersion and space distribution uniformity of the plasma is guaranteed, the concentration of active oxides in the plasma is enhanced, the contact efficiency of products and a processed object in application is improved, and further the working efficiency of the whole system is improved;

(2) furthermore, the gas flow is regulated through the flow controller, so that the Lorentz force and the thrust acting on the plasma are optimally adapted, the ionization intensity of the plasma is enhanced, under the action, the enhancement of the ionization intensity enables the generation area of the plasma to be larger and more uniform, the length of the jet flow is longer, and stable discharge with good repeatability is maintained;

(3) the gas temperature of the plasma is close to the room temperature, the concentration of short-life and high-activity components in the plasma is improved, the contact is more comprehensive in the aspects of biological application and material treatment, the overall treatment efficiency is higher, a better effect can be obtained in a shorter time, and the working efficiency of the whole device is improved.

Drawings

FIG. 1 is a schematic structural diagram of a magnetic field enhanced plasma jet generating device using a solid rod-shaped cylindrical electrode according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a magnetic field enhanced plasma jet generating device using a solid rod-shaped needle electrode according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a magnetic field enhanced plasma jet generating device using a tapered electrode with a smooth surface according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a magnetic field enhanced plasma jet generating device using a tapered electrode with a spiral structure on the surface according to an embodiment of the present invention.

The same reference numbers will be used throughout the drawings to refer to the same or like elements or structures, wherein:

the device comprises a high-voltage power supply 1, a high-voltage wire 2, a first medium pipe 3, a first electrode 4, a second medium pipe 5, a second electrode 6, a gas pipeline 7, an annular magnet 8, a grounding wire 9, a gas output port 10, a plasma jet flow 11, a gas input port 12, a flow controller 13, a gas conveying pipeline 14 and a gas source 15.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

In the present application, the terms "first," "second," and the like (if any) in the description and the drawings are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.

Fig. 1 is a schematic structural diagram of a magnetic field enhanced plasma jet generating device using a solid rod-shaped cylindrical electrode according to an embodiment of the present invention. Referring to fig. 1, a detailed description will be given of the magnetic field enhanced plasma jet generating device in this embodiment with reference to fig. 2 to 4.

The magnetic field enhanced plasma jet generating device comprises a plasma jet generating unit and a ring magnet. The plasma jet generating unit is used for generating plasma jet and outputting the plasma jet through a gas output pipeline of the plasma jet generating unit. The annular magnet is arranged on the outer side of the gas output pipeline in a surrounding mode and used for generating a magnetic field in the gas output pipeline, and the direction of the Lorentz force provided by the magnetic field for the plasma jet is consistent with the flowing direction of the plasma jet so as to accelerate the flowing speed of the plasma jet.

The magnetic field generated by the ring magnet may also enhance the ionization strength of the plasma jet. In the embodiment, the magnetic field can be provided by adopting the annular permanent magnet, and the annular magnet can select two modes of radial magnetization and longitudinal magnetization; the magnetic field can also be provided by electrifying an electromagnet coil, and the magnitude of the magnetic field can be adjusted by changing the magnitude of current in the coil.

According to an embodiment of the present invention, the plasma jet generating unit includes a first medium pipe 3, a first electrode 4, a second electrode 6, a high voltage power supply 1, and a gas source 15. A gas source 15 is connected to the first medium pipe 3, and preferably a gas inlet 12 is provided in the outer wall of the high-pressure side end of the first medium pipe, and the gas in the gas source 15 enters the first medium pipe through the gas inlet 12.

The first electrode 4 is inserted into the first medium pipe 3 through one end of the first medium pipe 3 and is coaxial with the first medium pipe 3, a gas pipeline 7 is formed between the first electrode 4 and the first medium pipe 3, and the formed gas pipeline is of a single medium structure. The other end of the first medium pipe is open and serves as a gas outlet 10 of the gas pipe 7. A portion of the gas piping 7 on the gas delivery side serves as a gas output piping.

The second electrode 6 surrounds the outer wall of the first medium pipe arranged at the gas output pipeline, and the annular magnet 8 surrounds the outer side of the second electrode 6. The first electrode 4 is connected with the high-voltage power supply 1, and the second electrode 6 is grounded through a grounding wire 9; alternatively, the first electrode 4 is grounded via a ground line 9, and the second electrode 6 is connected to the high-voltage power supply 1. It is noted that as different electrodes the direction of the applied magnetic field has to be changed accordingly, ensuring that the direction of the lorentz force to which the charged particles are subjected is longitudinal. The first electrode, the second electrode, and other conductive materials in the device may be one of tungsten, aluminum, copper, and other metal materials.

The electrode connected with the high-voltage power supply is a high-voltage electrode, and the exposed part of the high-voltage electrode is connected with the output end of the high-voltage power supply; the grounded electrode is a dielectric barrier electrode and serves as a ground electrode. The annular magnet is coaxially arranged on the outer side of the dielectric barrier electrode and keeps a certain distance with the dielectric barrier electrode.

Preferably, the first electrode is connected with a high-voltage power supply to serve as a high-voltage electrode, and the second electrode is grounded to serve as a dielectric barrier electrode, so that the dielectric barrier electrode is an annular metal piece and is coaxially attached to the outer wall of the first dielectric tube, and the discharge electrodes uniformly distributed in the space position of the coaxial structure are beneficial to obtaining large-area plasma and improving the uniformity of large-size space discharge.

Further, the position of the annular metal part as a grounding electrode can be moved, and the grounding electrode is mainly divided into two types: one is that the area where the annular metal part is located completely contains a high-voltage electrode; the second is that the environment metal piece is positioned at one end of the gas output port of the first medium pipe and has a certain distance with the end with the smaller diameter of the high-voltage electrode. The distribution of the space electric field can be adjusted by the difference of the positions of the annular metal pieces, so that electric field components in different directions are obtained, the effect of the magnetic field is enhanced, and the intensity of the ionized wave is improved.

The magnetic induction intensity of the magnetic field generated by the ring magnet satisfying the left-hand rule is determined by the following formula:

F＝BIL

where F denotes the lorentz force, B denotes the magnetic field induction, I denotes the set of components of the current flowing through the gas gap perpendicular to the direction of the magnetic field, and L denotes the set of components of the air gap distance in the direction perpendicular to the gas flow. The ring magnets with different magnetizing modes are selected according to different positions of the ring-shaped metal piece, so that the intensity of the ionized wave can be effectively improved. Preferably, the included angle between the discharge section and the air passage is 90 degrees, so that the magnetic field acting force borne by the plasma discharge channel is the largest under the action of the same magnetic induction intensity, and the discharge ionization is enhanced.

Preferably, the plasma jet generating unit may further include a second medium pipe 5, the second medium pipe 5 is coaxially attached to the first electrode, and the formed gas pipeline is a double-medium structure. The first medium pipe and the second medium pipe are made of quartz glass or ceramic. The double-medium structure in the embodiment can prevent partial spark discharge or arc discharge from being formed in the discharge space, stable gas discharge is realized, and the whole discharge process is more uniform and mild.

The area of the second electrode corresponding to the inner air gap of the first medium tube (i.e. the gas pipe) is called the discharge area. The first medium pipe forms uniform and stable long plasma jet at a gas output port of the first medium pipe, and the part of the area for forming the jet is called an afterglow area; the annular magnet generates a magnetic field in the first medium tube, the direction of the magnetic field is perpendicular to the component of partial current or current direction flowing through the gas gap, the left-hand rule is met, the direction of the magnetic field acting force is consistent with the direction of the gas flow acting force, and the flowing speed of the plasma jet is accelerated.

In this embodiment, the working process and principle of the magnetic field enhanced plasma jet generating device are as follows: the voltage is applied to the high-voltage electrode, so that an air gap between the first medium pipe and the second medium pipe is broken down to generate plasma, on one hand, the generated plasma is pushed by airflow to move towards the direction of an output port of the pipeline, on the other hand, in a magnetic field orthogonal to an electric field, charged particles in the plasma are subjected to the action of Lorentz force, the direction and the size of magnetic induction intensity of the magnetic field are changed, forward or reverse Lorentz force acting on the charged particles can be obtained, and the change of the length of the plasma jet flow is more directly expressed. In practical application, a magnetic field orthogonal to an electric field is provided, so that charged particles obtain Lorentz force in the same direction as air flow to obtain a longer and larger-area uniform plasma jet; in the mechanism aspect, the addition of the magnetic field enhances the ionization strength of dielectric barrier discharge, improves the concentration of active ingredients in jet flow, can greatly improve the treatment efficiency in the aspect of biomedical application, and obtains better treatment effect in a short time.

According to an embodiment of the invention, the plasma-jet generating unit further comprises a flow controller 13. The flow controller 13 is connected between the gas source 15 and the first medium pipe 3 for controlling the flow of the gas from the gas source 15 into the first medium pipe 3.

The discharge electric field can be changed by adjusting the gas flow, and the Lorentz force borne by the charged particles is generated under the combined action of the electric field and the magnetic field, namely the Lorentz force in the optimal direction and magnitude can be obtained by changing the gas flow or the magnetic induction intensity of the magnetic field; the combination of the two can better control the discharge mode of the plasma jet and adjust the length of the jet, thereby changing the characteristics of the plasma such as electron density, active products, gas temperature and the like, being another regulation and control mode besides changing the electrical parameters of the power supply and being beneficial to obtaining the most accurate characteristic parameters of the plasma according to the actual requirements.

According to an embodiment of the invention, the high voltage power supply is an alternating current power supply or a high voltage pulse power supply, and the discharge between the first electrode and the second electrode is regulated by controlling the voltage of the high voltage power supply. The high-voltage pulse power supply can be a second pulse power supply or a nanosecond pulse power supply. When an alternating current power supply is used, the direction of discharge current is changed continuously, and a magnetic field synchronous with the direction of the current is adopted, so that the direction of Lorentz force borne by charged particles is consistent with the direction of air flow. By controlling the low-frequency voltage applied to the high-voltage electrode, the discharge intensity of the dielectric barrier electrode can be regulated and controlled, and the discharge uniformity of the excitation area is improved.

According to the embodiment of the invention, the first electrode is a tapered electrode with a smooth surface, a tapered electrode with a spiral structure arranged on the surface, a solid rod-shaped cylindrical electrode or a solid rod-shaped needle electrode. Preferably, when the first electrode is a solid rod-shaped cylindrical electrode or a solid rod-shaped needle electrode, the second medium tube may be coaxially attached to the outer side of the first electrode. When the first electrode is a solid rod-shaped needle electrode, a preset distance is kept between the second electrode and the end, with the smaller diameter, of the solid rod-shaped needle electrode.

Taking the first electrode to be connected with a high-voltage power supply and the second electrode to be grounded as an example, one end of the first electrode is connected with the high-voltage power supply through a high-voltage lead 2, the other end of the first electrode is tightly attached to a second medium tube and is inserted into the first medium tube together, the distance between the air gap outside the second medium tube and the front side of the inner side of the first medium tube is 0.5-4 mm, the diameter of the first electrode is 1-8 mm, the thickness of the second medium tube is 0.5mm, the thickness of the first medium tube is 1mm, the outer side of the second electrode is directly connected with the ground, the inner side of the second electrode is tightly attached to the outer side of the first medium tube, the annular magnet is arranged outside the second electrode, the gap between the annular magnet and the second electrode is 5mm, and the central axes of all annular structures are overlapped to form a coaxial structure. The upper end of the first medium pipe is provided with an opening of a gas inlet, the opening is connected with a gas source through a pipeline, and the diameter of the gas inlet is 4-6 mm.

Referring to fig. 1, the first electrode may be a solid rod-shaped cylindrical electrode with a diameter of 3mm and a distance of 2.5mm from the nozzle opening of the first medium pipe, the lower end of the second electrode is 5mm from the nozzle opening of the first medium pipe, and the air gap distance is 1 mm. Plasma is generated in the annular air gap, and the generated discharge electric field is a transverse electric field and horizontally diverged outwards by the middle high-voltage electrode; the applied magnetic field is a longitudinal magnetic field and is orthogonal to the direction of the electric field, so that charged particles in the plasma obtain longitudinal Lorentz force, the ionization intensity is enhanced, and uniform plasma jet with a longer and larger area is obtained.

Preferably, referring to fig. 1, the first electrode is a solid rod-shaped cylindrical electrode as a high voltage electrode, the diameter of the first electrode is 3mm, the upper end of the first electrode is connected with a high voltage power supply 1 through a high voltage lead 2, the other end of the first electrode is tightly attached to a second medium tube 5 and is inserted into the first medium tube 3, the thickness of the second medium tube 5 is 0.5mm, the inner diameter of the first medium tube 3 is 6mm, the thickness of the first medium tube is 1mm, and the distance between the lower end of the second medium tube 5 and a gas outlet 10 is 2 mm; the upper end of the first medium pipe 3 is provided with a gas inlet 12, and the gas inlet 12 is connected with a gas source 15 through a flow controller 13 and a gas conveying pipeline 14; the second electrode 6 is tightly attached to one side of the gas output port 10 of the first medium pipe 3, the thickness of the second electrode is 3mm, the distance between the second electrode and the gas output port 10 is 5mm, and the second electrode 6 is connected with the ground through the grounding wire 9. The thickness of the annular magnet 8 is 5mm, the annular magnet is coaxially sleeved on the outer side of the second electrode 6, and the gap distance between the annular magnet and the second electrode is 3 mm. A plasma jet 11 is generated below the gas outlet 10. The high-voltage power supply can be a high-voltage alternating-current power supply, the voltage frequency is 1-40 kHz, and the voltage amplitude is 3-10 kV; or a delicate or nanosecond high-voltage pulse power supply can be selected, the voltage frequency is 0.2-4 kHz, the voltage pulse width is 0.3-5 mus, and the voltage amplitude is 1-30 kV. The material of the first electrode is metal tungsten, the material of the second electrode is brass, the material of the first medium pipe and the second medium pipe is quartz glass, and the material of the gas conveying pipeline is polytetrafluoroethylene.

Referring to fig. 2, the first electrode may be a solid rod-shaped needle electrode, the diameter of which is 3mm, the curvature radius of the needle tip is 0.36mm, the needle tip is 9mm away from the nozzle opening of the first medium tube, the length of the dielectric barrier electrode is 5mm, and the lower end of the dielectric barrier electrode is 2mm away from the nozzle opening, i.e. the needle tip of the first electrode is 2mm away from the upper end of the dielectric barrier electrode. The breakdown of the air gap occurs in the area between the needle point and the dielectric barrier electrode, the generated discharge electric field is mostly an electric field in the vertical direction, and the plasma firstly pushes towards the nozzle direction under the action of the airflow; the applied magnetic field is a transverse magnetic field which is orthogonal to the vertical component of the electric field, the gas flow is adjusted to realize the optimal adaptation to the Lorentz force borne by the charged particles, and the plasma jet with stronger ionization intensity and longer length is obtained under the combined action of the gas flow and the charged particles. The solid rod-shaped needle electrode is adopted, so that the breakdown voltage of discharge can be obviously reduced, the action of a magnetic field on the discharge is more obvious under the same voltage parameter, and more efficient plasma jet is obtained.

Referring to fig. 3, the first electrode may be a tapered electrode with a smooth surface, and the second dielectric tube is not arranged under the electrode structure, and the maximum air gap distance between the tapered electrode and the inner side of the first dielectric tube is 4mm, and the minimum air gap distance is 0.5 mm. The coaxial non-parallel face-to-face structure is adopted to stabilize the dielectric barrier discharge, generate uniform plasma only at a fixed position, concentrate the discharge to obtain an electric field in the horizontal direction, have more obvious action with a magnetic field, enhance ionization and ensure that the discharge mode is more uniform and stable. With the electrode with the conical structure, plasma can be obtained at a larger air gap, the discharge is firstly broken down from the minimum position of the gap, and the function of ignition propulsion is realized, so that the plasma can be generated at the gap distance of 4 mm. And the tail end of the high-voltage electrode has a small diameter, so that the electric field intensity can be effectively enhanced.

Referring to fig. 4, the first electrode may be a conical electrode with a spiral structure on the surface, and the second medium tube is not arranged under the electrode structure, and the air gap distance of the discharge is 4mm at most and 0.5mm at most. The spiral protruding structure is arranged on the surface of the conical electrode, so that the breakdown voltage of discharge can be remarkably reduced, the discharge can be stably concentrated at the position of the thread, a more concentrated and stable electric field is generated, the magnetic field effect is obvious, and the ionization intensity is stronger.

In this embodiment, the magnetic field enhanced plasma jet generating device may be applied to a plurality of working gases, and different reactant gases may be selected according to the actual application of the jet, and may be, but not limited to, one or more mixed gases of helium, argon, air, nitrogen, oxygen, and the like. The plasma sterilization and air sterilization device can be used for plasma sterilization and air sterilization, can directly contact jet flow for treatment, and can also directly introduce ambient air into the medium tube, and both the ambient air and the medium tube enhance ionization through a magnetic field to improve the concentration of active ingredients so that the sterilization effect is more obvious. The method can also be applied to treatment of wound healing, generally air is used as working gas, air discharge is more stable and uniform due to the addition of the magnetic field, the gas temperature is close to room temperature and is very friendly to the wound, and the increase of the concentration of the active oxide has a very good promoting effect on the early coagulation stage of the wound healing.

The magnetic field enhanced plasma jet generating device can be applied to sterilization, percutaneous administration or wound healing. According to the device disclosed by the embodiment of the invention, under the action of low frequency and high pressure, the plasma can be kept in a dispersion state in a larger air gap space, so that the uniformity of the spatial distribution of the plasma is ensured; under the action of a magnetic field, the ionization strength of dielectric barrier discharge is enhanced, so that the transverse section of the jet flow is larger, the length is longer, the uniformity of a radial space electric field is promoted, and the strength of an axial electric field is increased; on the other hand, the concentration of active ingredients in the plasma is increased, and the high-concentration large-area long plasma jet is in forced demand in various application fields. The large-area killing work has higher efficiency, the high ionization strength better promotes the penetration of the medicine in the skin, and the high-concentration active ingredients play a more efficient role in wound healing.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A magnetic field enhanced plasma jet generating device, comprising:

the plasma jet generating unit is used for generating plasma jet and outputting the plasma jet through a gas output pipeline of the plasma jet generating unit;

the annular magnet is arranged on the outer side of the gas output pipeline in a surrounding mode and used for generating a magnetic field in the gas output pipeline, and the direction of the Lorentz force provided by the plasma jet flow by the magnetic field is consistent with the flowing direction of the plasma jet flow, so that the flowing speed of the plasma jet flow is accelerated.

2. The magnetic field enhanced plasma jet generating device according to claim 1, wherein the plasma jet generating unit comprises: the electrode structure comprises a first medium pipe, a first electrode, a second electrode, a high-voltage power supply and an air source, wherein the air source is communicated with the first medium pipe;

the first electrode is inserted into the first medium pipe through one end of the first medium pipe and is coaxial with the first medium pipe, and a gas pipeline is formed between the first electrode and the first medium pipe; the other end of the first medium pipe is opened and serves as a gas output port of the gas pipeline; a part of the gas pipe on the gas output side serves as the gas output pipe;

the second electrode is arranged around the outer wall of the first medium pipe at the gas output pipeline, and the annular magnet is arranged around the outer side of the second electrode;

the first electrode and the second electrode are respectively connected with the high-voltage power supply and the ground, or the first electrode and the second electrode are respectively connected with the ground and the high-voltage power supply.

3. The magnetic field enhanced plasma jet generating device according to claim 2, wherein the plasma jet generating unit further comprises: and the flow controller is connected between the gas source and the first medium pipe and is used for controlling the flow of the gas input into the first medium pipe from the gas source.

4. The apparatus according to claim 2, wherein the high voltage power supply is an ac power supply or a high voltage pulse power supply, and the discharge between the first electrode and the second electrode is adjusted by controlling a voltage of the high voltage power supply.

5. The magnetic field enhanced plasma jet generating device according to any one of claims 2 to 4, wherein the first electrode is a tapered electrode with a smooth surface or a tapered electrode with a spiral structure on the surface.

6. The magnetic field enhanced plasma jet generating device according to any one of claims 2 to 4, wherein said first electrode is a solid rod-like cylindrical electrode or a solid rod-like needle electrode, and said plasma jet generating unit further comprises: and the second medium pipe is coaxially attached to the first electrode.

7. The apparatus according to claim 6, wherein the first dielectric tube and the second dielectric tube are made of quartz glass or ceramic.

8. The apparatus according to claim 6, wherein when the first electrode is a solid rod-like needle electrode, the second electrode is spaced from a smaller diameter end of the solid rod-like needle electrode by a predetermined distance.