A portable plasma experimental device for field tests

Abstract

The invention discloses a portable plasma experimental device for field tests, comprising a flat-mounted probe or other sensor (1), a mechanical pump (2), a portable barometer (3), a plasma generator (4), a high-frequency power supply (5), and a gas source (6); a three-way interface is provided at one end of the plasma generator (4), wherein the first interface of the three-way interface is a probe port (7), the second interface of the three-way interface is connected to the mechanical pump (2), and the third interface of the three-way interface is connected to the portable barometer (3); the other end of the plasma generator (4) is connected to the gas source (6); a hollow solenoid (11) is wound on the outer surface of the plasma generator (4); and the high-frequency power supply (5) is connected to the hollow solenoid (11). The device of the invention is small in size, but has an ingenious structure and is simple to operate. The plasma distribution area meets the requirements of probe measurement and can work in a steady state for a long time.

Description

Technical Field

[0001] The invention relates to the field of plasma generating devices, in particular to a portable plasma experimental device for field tests. Background Art

[0002] When a spacecraft re-enters the atmosphere at a very high speed, it will rub against and squeeze the dense upper atmosphere. The temperature of the spacecraft surface will surge to over 3000K, which will lead to the ionization of atmospheric molecules. The ionized atmosphere will form a dense plasma on and around the target surface. In addition, because the heat-resistant material of the target itself will undergo ablation and ionization in a high-temperature environment, the electron density around it will increase significantly, forming a plasma with a certain thickness surrounding the spacecraft, the so-called "plasma sheath". The plasma sheath will directly affect the heat conduction, aerodynamic process and radio communication of the spacecraft. The formation of the sheath poses a serious threat to the effective transmission of the target signal.

[0003] At present, international military powers are vigorously exploring and developing research solutions to the plasma sheath. However, due to the lack of effective plasma diagnostic methods, our understanding of sheath plasma parameters is very low. Before online diagnostic detection in space, the main work was to develop theoretical calculation models for the sheath. However, as the research continued to deepen, people found that there was a large difference between the theoretical calculation model and the actual plasma sheath problem. Therefore, the development of the country's future aerospace industry urgently needs real plasma parameter experimental data for verification. As an effective tool for diagnosing plasma, the flat-mounted probe has been used to diagnose parameters in stable plasma environments and complex plasma environments.

[0004] The cost of the mounted experiment is high. After the instrument is installed, a real plasma environment needs to be provided to check the installation and data measurement of the flat-mounted probe acquisition system. The plasma calibration device involves multiple technologies such as vacuum acquisition system, vacuum chamber, vacuum measurement, plasma discharge, etc. It is generally large in size and not suitable for field experiments. Although there are many devices that can generate plasma, there are many problems with the application of existing plasma generating devices in field experiments, which are mainly reflected in:

[0005] (1) Vacuum degree of the device

[0006] The generation of high-density plasma requires a high degree of vacuum, because the background vacuum of the device affects the ionization degree of the excited plasma and the coupling efficiency of the discharge source, which in turn affects the electron density of the plasma. Under the same coupling power, the electron density range under rough vacuum is much lower than that under high vacuum. Because there are diatomic molecules such as N2, O2, CO2 and other particles in the background vacuum, the corresponding ionization energy is much higher than the ionization energy of argon (15.76eV) and the excitation energy of argon atoms (11.5eV), and there are energy levels such as rotational vibration. At the same time, the atomic free radicals will also undergo complex physical processes such as excitation, recombination, and quenching with the high-energy electrons of the plasma, thereby consuming the excited charged particles in the plasma. Therefore, the power coupling efficiency of the plasma and the discharge source is reduced. On the other hand, there are difficulties in the vacuum sealing of the connection between the plasma device and the carrier probe, and it cannot be effectively sealed by the sealing structure commonly used in laboratory environments. Therefore, in the case of simplifying the vacuum two- and three-stage pumping system, the sealing link of this connection is a place that needs to be focused on. The design should not only consider the portability of the device, but also consider not affecting the safety of the carrier target structure.

[0007] (2) Screening of plasma sources

[0008] The electron density parameter range of plasma is heavily dependent on the plasma excitation method. At present, the discharge methods for exciting plasma include DC glow discharge, oxide cathode discharge, radio frequency discharge (capacitor, inductor and spiral wave), microwave discharge, dielectric barrier discharge, jet and other discharge methods. Although other discharge methods except DC glow discharge can produce a higher electron density range, there are several discharge methods that cannot meet the design requirements due to their own discharge characteristics. Although the oxide cathode can produce a large area of ​​plasma distribution and a higher plasma electron density parameter, its relatively harsh and complex discharge requirements, such as complex electrode structure, cannot be exposed to the atmosphere, and cannot be used for mixed discharge of chemical substances and electrode temperature rise and fall before and after discharge, make it impossible to use it in our calibration device, because the device must be exposed to the atmosphere when conducting the calibration experiment. The spiral wave discharge in the radio frequency discharge requires an additional magnetic field coil, and the higher central confinement magnetic field (such as the common 300-800G) will increase the cost and size of the device. The electron density limit of capacitive coupled discharge is about 10, and the commonly used industrial frequency radio frequency is 13.56MHz. This frequency has radio frequency interference problems on the saturated flow collection of the probe and the electromagnetic system of the probe, which will affect the stability of the collection system. Jet and dielectric barrier discharge cannot produce large-area high-density plasma areas and cannot eliminate the edge effect of the probe. Therefore, the discharge method currently suitable for the device is high-frequency AC (hundreds of kHz) inductance, and previous experimental theoretical studies have also shown that AC discharge will not affect the normal operation of the double-flat probe, because the collection flow of the double-flat probe satisfies Kirchhoff's current law, and the entire IV curve is symmetrical under positive and negative scanning bias.

[0009] (3) Potential impact of high frequency waves (radio frequency) on other instruments

[0010] High-power high-frequency (RF) induction heating may interfere with the normal and stable operation of other instruments and flat-mount probe acquisition circuits. Therefore, the input power and frequency of the discharge source should be carefully selected during the experiment. After preliminary research, we chose an AC discharge source in the 100kHz frequency band. The frequency of this frequency band is much lower than the industrial 13.56MHz, and the interference to probe measurement and other instruments is relatively small. The effective input power of the power source during the discharge process is controlled within 150W. Summary of the invention

[0011] The purpose of the present invention is to develop a portable plasma generator suitable for field test and calibration, and the calibration device designed does not affect the operation of other detectors and sensors. After installation, the measurement status of the flat-mounted probe is verified to ensure that the power supply and acquisition system are installed normally and can measure stably.

[0012] The present invention provides a portable plasma experimental device for field tests, which is suitable for field test calibration to solve the problems raised in the above background technology. The plasma experimental device is a portable discharge plasma and flat-pack probe diagnosis integrated device.

[0013] To achieve the above object, the present invention provides the following technical solutions:

[0014] A portable plasma experimental device for field experiments, comprising a flat-mounted probe or other sensor 1, a mechanical pump 2, a portable barometer 3, a plasma generating device 4, a high-frequency power supply 5, and a gas source 6;

[0015] A three-way interface is provided at one end of the plasma generating device 4, wherein the first interface of the three-way interface is a probe port 7, the second interface of the three-way interface is connected to the mechanical pump 2, and the third interface of the three-way interface is connected to the portable barometer 3;

[0016] The other end of the plasma generator 4 is connected to the gas source 6 ; the hollow solenoid 11 is wound on the outer surface of the plasma generator 4 ; and the high-frequency power supply 5 is connected to the hollow solenoid 11 .

[0017] Furthermore, the discharge chamber of the plasma generating device 4 is a quartz glass tank 10 .

[0018] Furthermore, the probe installed at the top of the probe rod is placed in the plasma environment through the device port at the probe port 7, and the baffle located on the probe rod has a sealing effect and can be pulled out when not in use.

[0019] Furthermore, the above-mentioned components work together to operate the device. The mechanical pump 2 is connected to the vacuum port of the device through a clamp to reduce the pressure of the device. The portable barometer 3 is connected to another vacuum port of the device through a clamp to monitor the gas pressure of the device. After reaching the target pressure at which the plasma generating device 4 can work, the gas source 6 introduces discharge gas into the device, and then the high-frequency power supply 5 is turned on to generate plasma.

[0020] Furthermore, the plasma generating device 4 includes a probe port 7, a 304 stainless steel baffle a8, a stainless steel plate a9 for fixing an O-ring, a quartz glass tank 10, a stainless steel plate b12 for fixing an O-ring, a 304 stainless steel baffle b13 and an air inlet 14, which are arranged in sequence; the hollow solenoid 11 is wound on the outer surface of the quartz glass tank 10.

[0021] Discharge power source

[0022] The heating of plasma by AC source in the 100kHz frequency band is mainly achieved through the interaction between charged particles and oscillating electric fields. The corresponding light charged particles, generally electrons, are coupled by energy heating by following the electric field oscillations, and collide and ionize with neutral particles during the heating process. The collision ionization excites the plasma and changes the electron energy distribution. It can be seen that the two main parameters affecting the electron density are the plasma electron-neutral particle collision frequency and the frequency of the discharge power source. The energy distribution function of the electron depends on the ratio of the two. Although high-frequency RF sources can effectively accelerate electron oscillations, there is a problem of large system interference. Therefore, we intend to adopt a low-frequency AC discharge method with a corresponding frequency range of hundreds of kHz. The reason for adopting this discharge in the hundreds of kHz frequency range is: on the one hand, when the frequency is reduced, the corresponding plasma electron energy distribution does not change significantly. For example, the corresponding value of the plasma collision frequency when discharging at 0.65Pa argon is 1.2×10 7 s -1 ,For an AC source with a frequency of 460kHz, the corresponding value is 4, while for a high frequency of 13.56MHz, it is about 0.15. The difference between the two is not very obvious, that is, the high-energy tail of the electron energy distribution that affects the electron density does not show much difference due to the change in frequency. Despite this, the electron density of RF discharge will still increase slightly compared with the electron density corresponding to 100kHz discharge. On the other hand, 100kHz discharge can effectively reduce the anisotropy of the electromagnetic field electrode boundary, and thus obtain a relatively uniform large-area plasma. In addition, 100kHz discharge can also effectively reduce the parasitic capacitance of the discharge circuit to the ground, and can effectively reduce the capacitive electric field, so that no additional Faraday shield is required to protect the discharge device. Relatively speaking, the discharge device is simpler and more portable to operate. In addition, the wavelength of the 100kHz field is larger than the high-frequency field relative to the coil scale, and the corresponding matching range is larger and easier to match, so it can effectively improve the matching efficiency of the power source.

[0023] Discharge chamber

[0024] Figure 2 In the probe port 7, the probe port 7 is converted through the three-way interface to enable it to have the functions of probe installation, air extraction, and air pressure measurement, with high integration. Figure 2 The device port at the probe port 7 is placed in the plasma environment, and the baffle on the probe rod has a sealing effect. It can be pulled out when not in use. The operation is simple and quick, and it can protect the device. In addition, the discharge process of this device does not need to maintain a too low vacuum environment, and the discharge pressure can be selected in a wider range. Considering the pressure environment required for discharge, the preparation time for generating plasma, and the portability of the experiment, a one-stage pump design is adopted, which is small in size, easy to carry, and can obtain an experimental environment pressure of 1 Pa within a few minutes. The air inlet is selected at Figure 2 At the 304 stainless steel baffle b13, this is mainly to consider that the argon gas entering the device can diffuse into the entire vacuum environment, ensuring that there are enough discharge gas molecules to collide in the vacuum environment between the spiral coils. In addition, the size of the discharge device will also affect the vacuum degree, as well as the plasma recombination rate at the wall boundary, etc., which will in turn affect the distribution area and scale range of the plasma. And the spiral coil used for discharge is wound on the quartz glass, with high space utilization, and can be used by connecting a high-frequency power supply, which is more convenient. Therefore, in order to meet the requirements of a relatively large probe measurement area and relatively portable characteristics, the cavity size used is a quartz glass cavity with a diameter of 7.5 cm and a length of 30 cm (such as Figure 2 ). The reason for using a quartz glass cavity is that the oscillating electric field of the power source can be coupled into the plasma through the quartz glass tank, and the electrons can be heated by electromagnetic field oscillation. The two ends of the quartz glass tank are sealed and connected by two parallel 304 stainless steel plates and O-rings. The openings at both ends will be changed and designed according to the experimental requirements. The necessary stainless steel vacuum flange window includes three necessary openings: the flat probe hole, the working gas injection flange port, and the vacuum pump. The device is required to be as integrated as possible, and the opening scheme is upgraded. The flat probe hole and the vacuum pump are operated through the same opening in the form of a tee.

[0025] Carrier connection seal

[0026] The placement of the back-end probe is designed based on the verification experiment in the early laboratory environment. For the boundary sealing connection involved in the later test site, it is planned to use a sealing ring with a special structure for sealing connection, and seal the system through the pressure difference inside and outside the device, using a specially designed sealing ring for sealing.

[0027] Advantages and positive effects:

[0028] The dual portable flat probe calibration experimental device has several outstanding advantages:

[0029] (1) The equipment is integrated and portable

[0030] Plasma calibration devices involve multiple technologies such as vacuum acquisition system, vacuum chamber, vacuum measurement, plasma discharge, etc. They are generally bulky and not suitable for field tests.

[0031] The device is small in size but cleverly constructed, integrating probe collection, vacuum acquisition, and pressure measurement.

[0032] The device has a high degree of integration and in terms of size, no external magnetic field or device cooling device is required when generating plasma. It is easy to install and carry.

[0033] (2) Easy to operate

[0034] Portable design, integrated device. After the device is connected, just turn on the high-frequency power switch to generate plasma.

[0035] (3) Plasma distribution area meets probe measurement requirements

[0036] The probe diagnostic theory assumes that the plasma is a flat plate plasma with infinite scale, so the probe measurement requires a larger plasma wrapping area, that is, a large area of ​​uniform plasma. The diagnostic theory requires reducing the plasma edge effect, so the plasma can only be regarded as a uniform large area plasma when the scale of the plasma is much larger than the probe radius.

[0037] (4) Able to work in a steady state for a long time

[0038] When the aircraft re-enters the atmosphere at a very high speed, it will rub against the dense upper atmosphere in the 60km area, resulting in the appearance of the blackout effect. There is a communication interruption of about 400s in this area. The probe acquisition needs to cover this area, so the acquisition time must be required to be more than 100s. Therefore, the corresponding stable discharge time of the verification device needs to include the effective acquisition time of the probe, and the steady-state discharge time of the device must meet more than 100s.

[0039] (5) Easy to build

[0040] Compared with other plasma discharge devices, this device is relatively simple in structure, small in size and easy to carry. At the same time, the device can also be improved to be suitable for other instrument detection or circuit measurement that requires plasma. In addition, the device is easy to build, which is conducive to large-scale use. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of the principle structure of the portable plasma experimental device of the present invention;

[0042] Figure 2 The figure is a schematic diagram of the appearance structure of the portable plasma generating device of the present invention.

[0043] In the figure; 1 a flat probe or other sensor, 2 a mechanical pump, 3 a portable barometer, 4 a plasma generator, 5 a high frequency power supply, 6 a gas source, 7 a probe port, 8 a 304 stainless steel baffle a, 9 a stainless steel plate a for fixing an O-ring, 10 a quartz glass tank, 11 a hollow solenoid, 12 a stainless steel plate b for fixing an O-ring, 13 a 304 stainless steel baffle b, and 14 an air inlet. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] See also Figure 1 , Figure 2 , a portable plasma experimental device for field tests, including a flat-mounted probe or other sensor 1, a mechanical pump 2, a portable barometer 3, a plasma generator 4, a high-frequency power supply 5 and a gas source 6. The discharge cavity of the plasma generator 4 is a quartz glass tank 10 (cylindrical glass cavity, diameter 75mm, length 300mm), one end of which is provided with a three-way interface, wherein the first interface of the three-way interface is a probe port 7, the second interface of the three-way interface is connected to the mechanical pump 2, and the third interface of the three-way interface is connected to the portable barometer 3. After the conversion of the three-way interface, it has the functions of probe installation, air extraction, and air pressure measurement, and has a high degree of integration. The probe installed at the top of the probe rod is also placed in the plasma environment through the device port at the probe port 7. The baffle located on the probe rod has a sealing effect, and can be pulled out when not in use. The operation is simple and quick, and the device can be protected. The other end of the plasma generator 4 is connected to the gas source 6. The hollow solenoid 11 is wound on the outer surface of the quartz glass tank (cylindrical glass cavity, diameter 75mm, length 300mm) 10. The high frequency power source 5 is connected to the hollow solenoid 11 .

[0046] like Figure 2 As shown, the schematic diagram of the appearance structure of the portable plasma generator of the present invention includes a probe port 7, a 304 stainless steel baffle a 8, a stainless steel plate a 9 for fixing an O-ring, a quartz glass tank 10, a stainless steel plate b 12 for fixing an O-ring, a 304 stainless steel baffle b 13 and an air inlet 14 arranged in sequence. Among them, the hollow solenoid 11 is wound on the outer surface of the quartz glass tank 10. The high-frequency power supply 5 is connected to the hollow solenoid 11. The air inlet 14 at the other end of the quartz glass tank 10 is connected to the air source 6 through a 6mm air pipe.

[0047] The various components work together to make the device operate. The mechanical pump 2 is connected to one of the three-way interfaces of the device through a clamp to reduce the pressure of the device. The portable barometer 3 is connected to the other interface of the three-way interface of the device through a clamp to monitor the gas pressure of the device. After reaching the target pressure at which the plasma generating device 4 can work, the gas source 6 introduces discharge gas into the device, and then the high-frequency power supply 5 is turned on to generate plasma.

[0048] The heating of plasma by AC source in the 100kHz frequency band is mainly achieved through the interaction between charged particles and oscillating electric fields. The corresponding light charged particles, generally electrons, are coupled by energy heating by following the electric field oscillations, and collide and ionize with neutral particles during the heating process. The collision ionization excites the plasma and changes the electron energy distribution. It can be seen that the two main parameters affecting the electron density are the plasma electron-neutral particle collision frequency and the frequency of the discharge power source. The energy distribution function of the electron depends on the ratio of the two. Although high-frequency RF sources can effectively accelerate electron oscillations, there is a problem of large system interference. Therefore, we intend to adopt a low-frequency AC discharge method with a corresponding frequency range of hundreds of kHz. The reason for adopting this discharge in the hundreds of kHz frequency range is: on the one hand, when the frequency is reduced, the corresponding plasma electron energy distribution does not change significantly. For example, the corresponding value of the plasma collision frequency when discharging at 0.65Pa argon is 1.2×10 7 s -1 ,For an AC source with a frequency of 460kHz, the corresponding value is 4, while for a high frequency of 13.56MHz, it is about 0.15. The difference between the two is not very obvious, that is, the high-energy tail of the electron energy distribution that affects the electron density does not show much difference due to the change in frequency. Despite this, the electron density of RF discharge will still increase slightly compared with the electron density corresponding to 100kHz discharge. On the other hand, 100kHz discharge can effectively reduce the anisotropy of the electromagnetic field electrode boundary, and thus obtain a relatively uniform large-area plasma. In addition, 100kHz discharge can also effectively reduce the parasitic capacitance of the discharge circuit to the ground, and can effectively reduce the capacitive electric field, so that no additional Faraday shield is required to protect the discharge device. Relatively speaking, the discharge device is simpler and more portable to operate. In addition, the wavelength of the 100kHz field is larger than the high-frequency field relative to the coil scale, and the corresponding matching range is larger and easier to match, so it can effectively improve the matching efficiency of the power source.

[0049] Figure 2 The probe port 7 is converted through a three-way interface to enable it to have the functions of probe installation, air extraction, and air pressure measurement, with a high degree of integration. Figure 2 The device port at the probe port 7 is placed in the plasma environment, and the baffle on the probe rod has a sealing effect. It can be pulled out when not in use. The operation is simple and quick, and it can protect the device. In addition, the discharge process of this device does not need to maintain a too low vacuum environment, and the discharge pressure can be selected in a wider range. Considering the pressure environment required for discharge, the preparation time for generating plasma, and the portability of the experiment, a one-stage pump design is adopted, which is small in size, easy to carry, and can obtain an experimental environment pressure of 1 Pa within a few minutes. The air inlet is selected at Figure 2The center of the 304 stainless steel baffle b 13 is mainly to consider that the argon gas entering the device can diffuse into the entire vacuum environment to ensure that there are enough discharge gas molecules to collide in the vacuum environment between the spiral coils. In addition, the size of the discharge device will also affect the vacuum degree, as well as the plasma recombination rate at the wall boundary, etc., which will in turn affect the distribution area and scale range of the plasma. And the spiral coil used for discharge is wound on quartz glass, with high space utilization, and can be used by connecting a high-frequency power supply, which is more convenient. Therefore, in order to meet the requirements of a relatively large probe measurement area and relatively portable characteristics, the cavity size used is a quartz glass cavity with a diameter of 7.5 cm and a length of 30 cm (such as Figure 2 ). The reason for using a quartz glass cavity is that the oscillating electric field of the power source can be coupled into the plasma through the quartz glass tank, and the electrons can be heated by electromagnetic field oscillation. The two ends of the quartz glass tank are sealed and connected by two parallel 304 stainless steel plates and O-rings. The openings at both ends will be changed and designed according to the experimental requirements. The necessary stainless steel vacuum flange window includes three necessary openings: the flat probe hole, the working gas injection flange port, and the vacuum pump. The device is required to be as integrated as possible, and the opening scheme is upgraded. The flat probe hole and the vacuum pump are operated through the same opening in the form of a tee.

[0050] Carrier (aircraft carrying flat-mounted probe) connection seal

[0051] The placement of the back-end probe is designed based on the verification experiment in the early laboratory environment. For the boundary sealing connection involved in the later test site, it is planned to use a sealing ring with a special structure for sealing connection, and seal the system through the pressure difference inside and outside the device, using a specially designed sealing ring for sealing.

[0052] When the portable plasma experimental device for field tests is used, when it is needed, the mechanical pump 2 is turned on, the portable barometer 3 is turned on, and the barometer display is observed. Within a few minutes, the pressure in the device drops to 1 Pa. The gas source 6 is turned on, and an appropriate amount of argon is introduced to make the barometer reading between 5 Pa and 50 Pa. When the high-frequency power switch button is turned on, the high-frequency power is output to the non-resonant induction coil, and the inductive coupling can generate 10 10 -10 11 cm -3 Then the signal of the instrument can be measured to check whether the circuit is normal.

[0053] The device is exquisitely designed, simple in structure, easy to use and carry. In addition, the device has strong scalability, for example, it can be used as a teaching aid for demonstration and basic scientific research on high-frequency plasma, etc.

[0054] The above-described embodiments are only descriptions of preferred implementations of the present invention, and the preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementations described. Without departing from the design spirit of the present invention, various modifications and improvements made by ordinary technicians in this field to the technical solution of the present invention should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A portable plasma experimental device for field experiments, characterized in that: It includes a flat probe, a mechanical pump (2), a portable barometer (3), a plasma generating device (4), a high frequency power supply (5), and a gas source (6); A three-way interface is provided at one end of the plasma generating device (4), wherein a first interface of the three-way interface is a probe port (7), a second interface of the three-way interface is connected to a mechanical pump (2), and a third interface of the three-way interface is connected to a portable barometer (3); The other end of the plasma generating device (4) is connected to a gas source (6); the hollow solenoid (11) is wound on the outer surface of the plasma generating device (4); and the high-frequency power source (5) is connected to the hollow solenoid (11).

2. The plasma experimental device according to claim 1, characterized in that: The discharge chamber of the plasma generating device (4) is a quartz glass tank (10).

3. The plasma experimental device according to claim 1, characterized in that: The probe installed at the top of the probe rod is placed in the plasma environment through the device port at the probe port (7). The baffle located on the probe rod has a sealing effect and can be pulled out when not in use.

4. The plasma experimental device according to claim 1, characterized in that: The above-mentioned components work together to operate the device. The mechanical pump (2) is connected to the vacuum port of the device through a clamp to reduce the pressure of the device. The portable barometer (3) is connected to another vacuum port of the device through a clamp to monitor the gas pressure of the device. After reaching the target pressure at which the plasma generating device (4) can work, the gas source (6) introduces discharge gas into the device, and then the high-frequency power supply (5) is turned on to generate plasma.

5. The plasma experimental device according to claim 1, characterized in that: The plasma generating device (4) comprises a probe port (7), a 304 stainless steel baffle a (8), a stainless steel plate a (9) for fixing an O-ring, a quartz glass tank (10), a stainless steel plate b (12) for fixing an O-ring, a 304 stainless steel baffle b (13) and an air inlet (14) which are arranged in sequence; a hollow solenoid (11) is wound around the outer surface of the quartz glass tank (10).

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