Method and system for measuring transport coefficient of impurities in high-temperature plasma

Abstract

The invention discloses a method and system for measuring the transport coefficient of impurities in high-temperature plasma, and relates to the technical field of nuclear fusion plasma physical analysis, and the method comprises the steps: measuring the spectral radiation evolution caused by the injection of impurities into plasma through a spectrum detector, giving the spatial evolution of electromagnetic wave radiation through inversion, and calculating the transport coefficient of the impurities in the plasma; spectral radiation intensity is proportional to impurity ion density; spatial distribution of disturbance amplitude and disturbance phase is given through spatial Fourier transform; through numerical solution of an impurity transport equation and successive approximation of experimental data of disturbance amplitude and phase, a diffusion coefficient and a convection velocity coefficient of the impurities are rapidly and effectively given. According to the invention, the development cost is reduced, the flexibility of impurity transport research is improved, and the range of impurity transport research is expanded.

Description

Technical Field

[0001] The present application relates to the technical field of nuclear fusion plasma physics analysis, and in particular to a method and system for measuring impurity transport coefficients in high-temperature plasma. Background Art

[0002] In magnetic confinement nuclear fusion devices, the basic components of plasma are hydrogen and its isotopes deuterium and tritium, and other components are defined as impurities. In tokamak plasma, the main sources of impurities are plasma facing material (Plasma Facing Material, PFM) and vacuum chamber gas wall. The interaction between plasma and plasma facing material includes physical and chemical processes such as sputtering, bubbling, arcing, thermal shock, etc., which are the main sources of heavy impurities. A large number of molecules or atoms are adsorbed on the wall of the vacuum chamber, and enter the plasma through low-energy desorption processes such as thermal desorption, particle bombardment and chemical reactions, which are the main sources of light impurities. The products of fusion reactions include alpha particles, which are also an inevitable source of impurities in tokamaks. According to the quasi-neutral conditions of plasma, under ideal conditions, the density of hydrogen isotope ions as fusion fuel should be equal to the electron density, while the charge number of impurity ions is several times or even dozens of times that of fuel ions. Under the same electron density, the presence of each impurity ion is equivalent to replacing the fuel ions with a charge number equal to its own, especially when the high Z impurities reach a certain concentration, which has a strong dilution effect on the fuel ions. In addition, according to the corona model theory, the plasma radiation power loss is proportional to the electron and ion density. Therefore, impurity concentration, especially heavy metal impurities, will lead to enhanced radiation power loss, thereby dissipating energy and reducing the confinement quality of the plasma. In addition, impurity concentration will dilute the fuel and reduce the fusion power. Therefore, understanding the impurity transport characteristics is of great significance for impurity control and improving fusion yield.

[0003] In high-temperature plasma, there are abundant impurity characteristic spectral lines. Therefore, by measuring these characteristic spectral lines, impurity transport research can be carried out. Most of these impurity characteristic spectral lines are in the ultraviolet band. Therefore, in order to measure these spectral lines, it is necessary to develop a vacuum ultraviolet or extreme ultraviolet spectral system. Since electromagnetic radiation in the ultraviolet band is easily absorbed by matter, a relatively large vacuum structure needs to be designed at the front end of the detector, and a high-resolution grating is used to separate the ultraviolet spectrum. As a result, the ultraviolet spectral system is generally large and lacks flexibility, which limits the research on impurity transport in fusion devices. Therefore, studying a flexible and fast method to determine the impurity transport coefficient is one of the key issues currently faced in conducting impurity transport research. Summary of the invention

[0004] In order to solve the problems of high development cost and poor flexibility caused by existing impurity characteristic measurement technology, the present application proposes a method and system for measuring impurity transport coefficient in high-temperature plasma. The present application adopts frequency modulation injection of impurities and spectral measurement technology to determine the impurity transport coefficient, which greatly reduces the development cost and improves the flexibility of impurity transport research, thereby quickly giving the impurity transport coefficient, providing a reliable and effective technical reference for plasma impurity transport research.

[0005] This application is implemented through the following technical solutions:

[0006] A method for measuring impurity transport coefficient in high temperature plasma, comprising:

[0007] Obtaining the spatiotemporal evolution signal of plasma radiation power caused by the injection of impurities into the plasma;

[0008] According to the spatiotemporal evolution signal of the plasma radiation power, the spatial distribution of the plasma radiation power density is obtained by using Abel transformation;

[0009] According to the spatial distribution of the plasma radiation power density, using Fourier transform to obtain the spatial distribution of the amplitude and phase of the plasma radiation;

[0010] By using the numerical solution technology of the impurity transport equation, the impurity diffusion coefficient and the impurity convection velocity coefficient are changed to approximate the spatial distribution of the amplitude and phase of the plasma radiation, so that the impurity diffusion coefficient and the convection velocity coefficient can be quickly determined.

[0011] In some embodiments, the step of obtaining the spatiotemporal evolution signal of plasma radiation power caused by the injection of impurities into the plasma specifically includes:

[0012] Using a wide-band spectrum detector to measure and obtain a time-space evolution signal of the plasma radiation power;

[0013] Wherein, the wide-band spectrum detector includes a plurality of detection channels, and the detection areas of the plurality of detection channels uniformly cover the entire plasma.

[0014] In some embodiments, the step of obtaining the spatiotemporal evolution signal of plasma radiation power caused by the injection of impurities into the plasma specifically includes:

[0015] A wide-band spectrum detector array is used to measure and obtain a time-space evolution signal of the plasma radiation power;

[0016] Wherein, the detection area of ​​the wide-band spectrum detector array uniformly covers the entire plasma.

[0017] In some embodiments, laser gas blowing injection technology is used to inject equal amounts of impurities into the plasma at a fixed frequency.

[0018] In some embodiments, the use of the impurity transport equation numerical solution technology to approximate the spatial distribution of the amplitude and phase of the plasma radiation by changing the impurity diffusion coefficient and the impurity convection velocity coefficient specifically includes:

[0019] By changing the impurity diffusion coefficient and the impurity convection velocity coefficient, the impurity transport equation is numerically solved to obtain the spatial distribution data of the amplitude and phase corresponding to a plurality of different coefficient groups;

[0020] The least square method is used to obtain a set of spatial distribution data of amplitude and phase with the smallest spatial distribution error of the amplitude and phase of the plasma radiation, and the corresponding impurity diffusion equation and impurity convection velocity coefficient are the impurity transport coefficient.

[0021] In some embodiments, the step of numerically solving the impurity transport equation by changing the impurity diffusion coefficient and the impurity convection velocity coefficient to obtain the spatial distribution data of amplitude and phase corresponding to a plurality of different coefficient groups specifically includes:

[0022] Setting a set of initial impurity diffusion coefficients and impurity convection velocity coefficients, and using the impurity transport equation, solving the spatial distribution data of the amplitude and phase corresponding to the initial coefficient set;

[0023] The impurity diffusion coefficient and the impurity convection velocity coefficient are gradually changed on the basis of the initial coefficients, so as to obtain the spatial distribution data of the amplitude and phase corresponding to a plurality of different coefficient groups.

[0024] In some embodiments, the impurity transport equation is expressed as:

[0025]

[0026] Where n z is the impurity density, D is the impurity diffusion coefficient, V is the impurity convection velocity coefficient, S Z is the impurity source, and r is the plasma minor radius.

[0027] On the other hand, the present application proposes a system for measuring impurity transport coefficient in high temperature plasma, comprising:

[0028] A signal acquisition module, the signal acquisition module is used to acquire a time-space evolution signal of plasma radiation power caused by impurities being input into the plasma;

[0029] A first transformation module, wherein the first transformation module uses Abel transformation to obtain the spatial distribution of plasma radiation power density according to the spatiotemporal evolution signal of the plasma radiation power;

[0030] A second transformation module, wherein the second transformation module uses Fourier transform to obtain the spatial distribution of the amplitude and phase of the plasma radiation according to the spatial distribution of the plasma radiation power density;

[0031] And, a numerical simulation module, which uses the numerical solution technology of the impurity transport equation to approximate the spatial distribution of the amplitude and phase of the plasma radiation by gradually changing the impurity diffusion coefficient and the impurity convection velocity coefficient, so as to quickly determine the impurity diffusion coefficient and the convection velocity coefficient.

[0032] In some embodiments, the signal acquisition module includes:

[0033] An impurity injection unit, wherein the impurity injection unit uses a laser blowing injection technology to inject impurities into the plasma at a fixed frequency and in equal amounts;

[0034] And, a spectrum detection unit, wherein the spectrum detection unit includes a wide-band spectrum detector with multiple detection channels or adopts a wide-band spectrum detector array, and the detection area uniformly covers the entire plasma, and measures the spatiotemporal evolution signal of the plasma radiation power.

[0035] In some embodiments, the numerical simulation module includes:

[0036] A numerical calculation unit, which numerically solves the impurity transport equation by changing the impurity diffusion coefficient and the impurity convection velocity coefficient to obtain spatial distribution data of amplitude and phase corresponding to a plurality of different coefficient groups;

[0037] And, a fitting unit, wherein the fitting unit uses the least square method to obtain a set of spatial distribution data of amplitude and phase with the smallest spatial distribution error of the amplitude and phase of the plasma radiation, and the corresponding impurity diffusion coefficient and impurity convection velocity coefficient are the impurity transport coefficient.

[0038] The present application proposes a method and system for measuring the impurity transport coefficient in high-temperature plasma. The method uses a spectral detector to measure the spectral radiation evolution caused by impurities injected into the plasma, and gives the spatial evolution of electromagnetic wave radiation through inversion. The spectral radiation intensity is proportional to the impurity ion density; the spatial distribution of the disturbance amplitude and the disturbance phase is given through spatial Fourier transform; the impurity transport equation is numerically solved, and the experimental data of the disturbance amplitude and phase are gradually approximated, so as to quickly and effectively give the impurity diffusion coefficient and the impurity convection velocity coefficient;

[0039] Compared with the prior art, the method and system for measuring the impurity transport coefficient in high temperature plasma proposed in this application adopts a small photoelectric detector, which greatly reduces the system development cost and improves the flexibility of impurity transport research;

[0040] The present application proposes a method and system for measuring the impurity transport coefficient in high-temperature plasma, which has no requirements on the type of impurities, greatly broadens the scope of impurity transport research, and provides technical support and reference for impurity transport research. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings described herein are used to provide a further understanding of the embodiments of the present application, constitute a part of the present application, and do not constitute a limitation on the embodiments of the present application. In the drawings:

[0042] Figure 1 This is a flow chart of the measurement method of an embodiment of the present application;

[0043] Figure 2 A schematic diagram of the detection area layout of the photodetector array used in the embodiment of the present application;

[0044] Figure 3 A schematic diagram of the spatial distribution of plasma radiation power density obtained by transformation in an embodiment of the present application;

[0045] Figure 4 This is a principle block diagram of the measurement system of an embodiment of the present application. DETAILED DESCRIPTION

[0046] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with examples and drawings. The illustrative implementation scheme of the present application and its description are only used to explain the present application and are not intended to limit the present application.

[0047] Example:

[0048] In order to achieve accurate analysis of impurity transport coefficients on nuclear fusion research devices, this embodiment proposes a method for measuring impurity transport coefficients in high-temperature plasma. This application is based on impurity modulation injection and spectral measurement technology to quickly determine the diffusion coefficient and convection velocity coefficient of impurities.

[0049] Specific as Figure 1 As shown, the method proposed in this embodiment specifically includes the following processes:

[0050] Step 100: Acquire a time-space evolution signal of plasma radiation power caused by impurities being injected into plasma.

[0051] In a nuclear fusion plasma device, plasma radiation can be described under the corona model as:

[0052] P rad =∑ i n i n e L(Te)(1)

[0053] Among them, n i is the ion density, n e is the electron density, L(Te) is the radiation cooling function, which is a function of the electron temperature. Since the radiation cooling function strongly depends on the electron temperature, the selection of the impurity source is very critical, and the influence of impurity injection on the plasma temperature must be prevented. The number of particles injected by laser blowing is about 10 18 , which is much smaller than the number of plasmas 10 20 Therefore, the impurities injected by laser blowing have basically no effect on the plasma temperature. In addition, if the amount of impurities injected is too little, the plasma will not respond, and if it is too much, the plasma parameters will change too much, and the perturbation effect cannot be achieved. Therefore, this embodiment can use laser blowing injection technology to inject impurities, so that the impurity injection is controllable, including the type of impurities injected, the injection amount, the injection frequency, etc. In order to facilitate the subsequent transport analysis, this embodiment can inject equal amounts (i.e., each pulse contains the same amount) of impurities (such as aluminum, iron, tungsten, etc.) into the plasma at a fixed frequency.

[0054] Under the condition of ensuring a small change in electron temperature, that is, the plasma radiation is proportional to the impurity ion and electron density (P rad ∝n i n e ), the distribution of impurity ions can be obtained by measuring the time evolution of plasma radiation and electron density. Electron density is a basic parameter of plasma, so the distribution of impurities can be obtained by properly setting the impurity radiation measurement profile.

[0055] Based on this, in step 100, a wide-band spectrum detector can be used to measure the spatiotemporal evolution signal of the plasma radiation power. The wide-band spectrum detector usually includes multiple detection channels, or multiple detectors (detector arrays) are used for simultaneous measurement, and the detection areas of the detectors are evenly distributed so that they cover the entire plasma. Optionally, the wide-band spectrum detector can use but is not limited to an AXUV photodetector, which has a wide measurement band range and a fast time response. Further, a photodetector array can be used to measure plasma radiation. For example, the photodetector array has a total of 16 detection channels, covering the entire plasma small cross section, such as Figure 2 shown.

[0056] Step 200: According to the spatiotemporal evolution signal of the plasma radiation power, the spatial distribution of the plasma radiation power density is obtained by using Abel transformation.

[0057] The radiation power signal given by the detector is an integrated signal, so the step 200 obtains the spatial distribution of the plasma radiation power density through Abel transformation (Abel transformation), such as Figure 3 As shown in the figure, the evolution of plasma radiation power caused by impurity injection and the deposition position of impurities are clearly shown. Plasma radiation is proportional to the impurity ion density, so in the case of perturbations, the evolution of radiation intensity can approximately replace the density evolution distribution of impurity ions.

[0058] Step 300: According to the spatial distribution of plasma radiation power density, Fourier transform is used to obtain the spatial distribution of the amplitude and phase of plasma radiation.

[0059] After the impurities are injected, the impurities begin to melt at the deposition position and begin to be transported to the surroundings. Therefore, the position corresponding to the maximum amplitude and the minimum phase is the impurity deposition position, and gradually diffuses to the surroundings. Based on this, this embodiment can select different injection techniques and different impurity types to obtain different deposition positions, and accurately study the impurity transport conditions at different positions.

[0060] Step 400, using the numerical solution technology of the impurity transport equation, by changing the impurity diffusion coefficient and the impurity convection velocity coefficient to approximate the spatial distribution of the amplitude and phase of plasma radiation, the impurity diffusion coefficient and the convection velocity coefficient can be quickly determined.

[0061] In a nuclear fusion plasma device, impurity transport can be described as:

[0062]

[0063] Among them, n z is the impurity density, is the impurity flux, D is the impurity diffusion coefficient, V is the impurity convection velocity coefficient, S Z is the impurity source. In the cylindrical coordinate system, the impurity transport equation can be simplified as:

[0064]

[0065] Where r is the plasma small radius. After the impurities enter the plasma, some impurities are not completely ionized, especially heavy impurities, and there is a strong transition radiation (characteristic line radiation spectrum). Most of the line radiation spectra are in the ultraviolet, vacuum ultraviolet and soft X-ray bands. Therefore, in experiments, usually the impurity transport equation is first numerically solved, and then the ultraviolet and soft X-ray data measured experimentally are fitted and approximated to give the diffusion coefficient and convection velocity coefficient of the impurities. Specifically, this step specifically includes the following processes:

[0066] Step 401 , by changing the impurity diffusion coefficient and the impurity convection velocity coefficient, numerically solving the impurity transport equation to obtain the spatial distribution data of the amplitude and phase corresponding to a plurality of different coefficient groups.

[0067] Preferably, step 401 can first set a set of initial impurity diffusion coefficients and impurity convection velocity coefficients, and use the impurity transport equation to solve and obtain the spatial distribution data of the amplitude and phase corresponding to the initial coefficient group; then, based on the initial coefficients, the impurity diffusion coefficients and impurity convection velocity coefficients are gradually changed to obtain the spatial distribution data of the amplitude and phase corresponding to multiple different coefficient groups.

[0068] Step 402, using the least square method to obtain a set of spatial distribution data of amplitude and phase with the smallest spatial distribution error of the amplitude and phase of plasma radiation, the corresponding impurity diffusion coefficient and impurity convection velocity coefficient are the impurity transport coefficient.

[0069] The measurement method proposed in this embodiment is based on the impurity modulation injection and spectral measurement technology, and combined with the numerical solution technology of the impurity transport equation, it can quickly and effectively determine the impurity diffusion coefficient and the impurity convection velocity coefficient. This embodiment uses a photodetector array, which greatly reduces the system development cost and improves the flexibility of impurity transport research; in addition, this embodiment has no requirements on the type of impurities, greatly broadens the scope of impurity transport research, and provides a technical basis for impurity transport research.

[0070] Based on the same technical concept as above, this embodiment also proposes a system for measuring impurity transport coefficient in high temperature plasma, such as Figure 4 As shown, the system proposed in this embodiment specifically includes:

[0071] A signal acquisition module is used to acquire a time-space evolution signal of plasma radiation power caused by impurities being injected into the plasma.

[0072] The first transformation module uses Abel transformation to obtain the spatial distribution of plasma radiation power density according to the spatiotemporal evolution signal of the plasma radiation power.

[0073] The second transformation module uses Fourier transform to obtain the spatial distribution of the amplitude and phase of the plasma radiation according to the spatial distribution of the plasma radiation power density.

[0074] And, a numerical simulation module, which uses the numerical solution technology of the impurity transport equation to approximate the spatial distribution of the amplitude and phase of plasma radiation by gradually changing the impurity diffusion coefficient and the impurity convection velocity coefficient, so as to quickly determine the impurity diffusion coefficient and convection velocity coefficient.

[0075] Furthermore, the signal acquisition module includes an impurity injection unit and a spectrum detection unit. The impurity injection unit can use laser gas blowing injection technology to inject impurities into the plasma at a fixed frequency and in equal amounts, i.e., each pulse contains the same amount of impurities; the spectrum detection unit uses a wide-band spectrum detector to measure the spatiotemporal evolution signal of the plasma radiation power, the wide-band spectrum detector includes multiple detection channels, or uses multiple photodetectors to form a detector array for measurement, and the detection area uniformly covers the entire plasma, and measures the spatiotemporal evolution signal of the plasma radiation power.

[0076] Furthermore, the numerical simulation module includes a numerical calculation unit and a fitting unit. The numerical calculation unit numerically solves the impurity transport equation by changing the impurity diffusion coefficient and the impurity convection velocity coefficient to obtain the spatial distribution data of the amplitude and phase corresponding to multiple different coefficient groups. The fitting unit uses the least squares method to obtain a set of spatial distribution data of the amplitude and phase with the smallest spatial distribution error with the amplitude and phase of plasma radiation, and the corresponding impurity diffusion coefficient and impurity convection velocity coefficient are the impurity transport coefficient.

[0077] Furthermore, the numerical calculation unit can be configured as:

[0078] A set of initial impurity diffusion coefficients and impurity convection velocity coefficients are set, and the impurity transport equation is used to solve the spatial distribution data of the amplitude and phase corresponding to the initial coefficient set;

[0079] The impurity diffusion coefficient and the impurity convection velocity coefficient are gradually changed on the basis of the initial coefficients, so as to obtain the spatial distribution data of the amplitude and phase corresponding to a plurality of different coefficient groups.

[0080] It should be noted that the impurity transport equation is as described in the above method and will not be elaborated here.

[0081] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0082] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0083] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0084] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0085] The specific implementation methods described above further illustrate the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only the specific implementation method of the present application and is not intended to limit the scope of protection of the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A method for measuring impurity transport coefficient in high temperature plasma, It is characterized in that include: Obtaining the spatiotemporal evolution signal of plasma radiation power caused by the injection of impurities into the plasma; According to the spatiotemporal evolution signal of the plasma radiation power, the spatial distribution of the plasma radiation power density is obtained by using Abel transformation; According to the spatial distribution of the plasma radiation power density, using Fourier transform to obtain the spatial distribution of the amplitude and phase of the plasma radiation; By using the numerical solution technology of the impurity transport equation, the impurity diffusion coefficient and the impurity convection velocity coefficient are changed to approximate the spatial distribution of the amplitude and phase of the plasma radiation, so that the impurity diffusion coefficient and the convection velocity coefficient can be quickly determined.

2. The method for measuring impurity transport coefficient in high temperature plasma according to claim 1, It is characterized in that The obtaining of the spatiotemporal evolution signal of the plasma radiation power caused by the injection of impurities into the plasma specifically includes: Using a wide-band spectrum detector to measure and obtain a time-space evolution signal of the plasma radiation power; Wherein, the wide-band spectrum detector includes a plurality of detection channels, and the detection areas of the plurality of detection channels uniformly cover the entire plasma.

3. The method for measuring impurity transport coefficient in high temperature plasma according to claim 1, It is characterized in that The obtaining of the spatiotemporal evolution signal of the plasma radiation power caused by the injection of impurities into the plasma specifically includes: A wide-band spectrum detector array is used to measure and obtain a time-space evolution signal of the plasma radiation power; Wherein, the detection area of ​​the wide-band spectrum detector array uniformly covers the entire plasma.

4. A method for measuring impurity transport coefficient in high temperature plasma according to any one of claims 1 to 3, It is characterized in that The laser gas blowing injection technology is adopted to inject equal amount of impurities into the plasma at a fixed frequency.

5. The method for measuring impurity transport coefficient in high temperature plasma according to claim 4, It is characterized in that The technique of numerically solving the impurity transport equation is used to approximate the spatial distribution of the amplitude and phase of the plasma radiation by changing the impurity diffusion coefficient and the impurity convection velocity coefficient, and specifically includes: By changing the impurity diffusion coefficient and the impurity convection velocity coefficient, the impurity transport equation is numerically solved to obtain the spatial distribution data of the amplitude and phase corresponding to a plurality of different coefficient groups; The least square method is used to obtain a set of spatial distribution data of amplitude and phase with the smallest spatial distribution error of the amplitude and phase of the plasma radiation, and the corresponding impurity diffusion equation and impurity convection velocity coefficient are the impurity transport coefficient.

6. The method for measuring impurity transport coefficient in high temperature plasma according to claim 5, It is characterized in that The method of numerically solving the impurity transport equation by changing the impurity diffusion coefficient and the impurity convection velocity coefficient to obtain the spatial distribution data of amplitude and phase corresponding to multiple different coefficient groups specifically includes: Setting a set of initial impurity diffusion coefficients and impurity convection velocity coefficients, and using the impurity transport equation, solving the spatial distribution data of the amplitude and phase corresponding to the initial coefficient set; The impurity diffusion coefficient and the impurity convection velocity coefficient are gradually changed on the basis of the initial coefficients, so as to obtain the spatial distribution data of the amplitude and phase corresponding to a plurality of different coefficient groups.

7. A method for measuring impurity transport coefficient in high temperature plasma according to claim 5 or 6, It is characterized in that The impurity transport equation is expressed as: Where n z is the impurity density, D is the impurity diffusion coefficient, V is the impurity convection velocity coefficient, S Z is the impurity source, and r is the plasma minor radius.

8. A system for measuring impurity transport coefficients in high temperature plasma. It is characterized in that include: A signal acquisition module, the signal acquisition module is used to acquire a time-space evolution signal of plasma radiation power caused by impurities being input into the plasma; A first transformation module, wherein the first transformation module uses Abel transformation to obtain the spatial distribution of plasma radiation power density according to the spatiotemporal evolution signal of the plasma radiation power; A second transformation module, wherein the second transformation module uses Fourier transform to obtain the spatial distribution of the amplitude and phase of the plasma radiation according to the spatial distribution of the plasma radiation power density; And, a numerical simulation module, which uses the numerical solution technology of the impurity transport equation to approximate the spatial distribution of the amplitude and phase of the plasma radiation by gradually changing the impurity diffusion coefficient and the impurity convection velocity coefficient, so as to quickly determine the impurity diffusion coefficient and the convection velocity coefficient.

9. A system for measuring impurity transport coefficient in high temperature plasma according to claim 8, It is characterized in that The signal acquisition module comprises: An impurity injection unit, wherein the impurity injection unit uses a laser blowing injection technology to inject impurities into the plasma at a fixed frequency and in equal amounts; And, a spectrum detection unit, wherein the spectrum detection unit includes a wide-band spectrum detector with multiple detection channels or adopts a wide-band spectrum detector array, and the detection area uniformly covers the entire plasma, and measures the spatiotemporal evolution signal of the plasma radiation power.

10. The impurity transport coefficient measurement system in high temperature plasma according to claim 8, It is characterized in that The numerical simulation module comprises: A numerical calculation unit, which numerically solves the impurity transport equation by changing the impurity diffusion coefficient and the impurity convection velocity coefficient to obtain spatial distribution data of amplitude and phase corresponding to a plurality of different coefficient groups; And, a fitting unit, wherein the fitting unit uses the least square method to obtain a set of spatial distribution data of amplitude and phase with the smallest spatial distribution error of the amplitude and phase of the plasma radiation, and the corresponding impurity diffusion coefficient and impurity convection velocity coefficient are the impurity transport coefficient.

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