A high-temperature magnetic fluid experimental loop suitable for advanced blanket research in fusion reactors

Abstract

The invention discloses a high-temperature magnetic fluid experimental loop suitable for the study of advanced blanket of fusion reactor, including a lithium-lead loop, a thermal oil loop, a cooling water loop and a gas path. Under the synergistic effect of a heater, a superconducting magnet, an experimental section, a mixer, a regenerator, a lithium-lead-thermal oil cooler, a thermal oil-water cooler, a cold trap, an expansion tank, a melting tank, a lithium-lead storage tank and a mechanical pump, liquid lithium-lead with high parameters such as temperature and flow rate can be obtained. There are experimental section channels in both horizontal and vertical directions inside the superconducting magnet, and the surface of the experimental section is covered with a heating plate, which can study the flow heat transfer characteristics of the advanced blanket of fusion reactor with high Reynolds number and high Hartmann number under the multi-field coupling effects such as magnetic field, thermal field, flow field and gravity field, and provide reliable experimental data for the design of advanced blanket of fusion reactor.

Description

Technical Field

[0001] The invention relates to the field of fusion reactor blanket, in particular to a high-temperature magnetic fluid experimental loop suitable for research on advanced blanket of fusion reactor. Background Art

[0002] Nuclear fusion obtains energy through plasma reactions (such as deuterium and tritium). Due to its many advantages such as abundant fuel, inherent safety, and no environmental pollution, it has always been regarded as the ultimate solution for human energy. The blanket is the core component facing the plasma in the fusion reactor. Its main functions include tritium breeding, energy conversion, and radiation shielding. According to the tritium breeder, the blanket can be divided into solid breeder blanket and liquid breeder blanket. Among them, the liquid breeder blanket uses lithium-lead alloy as tritium breeder and neutron multiplier. It has many advantages such as simple structure, high thermoelectric conversion efficiency, and online tritium extraction. It is considered to be an advanced blanket for fusion reactors. However, liquid lithium-lead itself is conductive. In the strong magnetic field environment of the tokamak fusion reactor, the flow of conductive fluid cuts the magnetic flux lines to generate induced current, thereby generating a Lorentz force that hinders the flow, showing an obvious magnetohydrodynamic (MHD) effect, which is mainly reflected in strong magnetic fields and large heat sources: (1) Due to the high intensity of the fusion magnetic field (~5T), its Hartmann number Ha is as high as 10 4 The strong Lorentz force completely changes the velocity profile and turbulence characteristics of the liquid lithium-lead flow, increasing the flow pressure drop; (2) the interaction between neutrons and liquid lithium-lead produces nuclear heat deposition, and the large volume heat source makes the Grashof number Gr in the blanket as high as 10 12 , which makes mixed convection play a key role in the momentum and energy transport of the fluid in the blanket. The above factors make the advanced blanket of fusion reactors have obvious multi-physics coupling effects, including magnetic field, thermal field, flow field and gravity field. Although the numerical calculation method has achieved remarkable results, its correctness needs to be verified by experiments. Therefore, the magnetohydrodynamic experimental loop is an essential experimental platform for the study of key scientific issues of the advanced blanket of fusion reactors.

[0003] In the field of research on the design of magnetohydrodynamic experimental loops for fusion reactors, Karlsruhe Institute of Technology (KIT) in Germany, University of California, Los Angeles (UCLA) in the United States, Kyoto University (KoU) in Japan, Joint Institute of High Temperature Research of Russian Academy of Sciences (JIHT), Institute of Nuclear Energy Safety Technology of Chinese Academy of Sciences (INEST) and Southwest Institute of Physics (SWIP) in China have designed magnetohydrodynamic experimental loops. However, the current experimental loop design has the following shortcomings: (1) The operating temperature and flow rate ranges are narrow, making it difficult to conduct experiments under actual advanced blanket conditions; (2) The magnetic field strength is low. In order to achieve a high Ha number, liquid metals with high electrical conductivity, such as mercury, lithium, NaK, GaInSn, etc., are often used instead of lithium lead for experiments. However, the thermophysical properties of these media are very different from those of lithium lead, and the experimental data are difficult to apply to advanced blanket design; (3) The cross-sectional size of the experimental section is small, which is far from the actual size of the lithium lead channel of the advanced blanket of the fusion reactor and cannot reflect the actual flow state; (4) The design of the experimental section is mostly focused on single characteristic research, such as measuring the hydraulic pressure drop, and lacks research on the multi-field coupling effects such as magnetic field, thermal field, gravity field and flow field. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a high-temperature magnetic fluid experimental loop suitable for the research of advanced blanket of fusion reactor, which is a high-temperature magnetic fluid experimental loop including a lithium-lead loop, a thermal oil loop, a cooling water loop and a gas path. Under the synergistic effect of equipment such as a heater, a superconducting magnet, an experimental section, a mixer, a regenerator, a lithium-lead-thermal oil cooler, a thermal oil-water cooler, a cold trap, an expansion tank, a melting tank, a liquid storage tank and a mechanical pump, high-temperature and high-flow liquid lithium-lead can be obtained. Under the multi-field coupling effect of magnetic field, thermal field, flow field and gravity field, key scientific issues of advanced blanket of fusion reactor can be studied.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A high-temperature magnetic fluid experimental loop suitable for advanced blanket research of fusion reactors, characterized in that lithium-lead alloy is used as a circulating working fluid, the experimental loop includes a lithium-lead loop, a thermal oil loop, a cooling water loop and a gas circuit; wherein the lithium-lead loop includes a heater, a superconducting magnet, an experimental section, a mixer, a regenerator, a lithium-lead-thermal oil cooler, a cold trap, an expansion tank, a melting tank, a lithium-lead storage tank and a mechanical pump, etc., the thermal oil loop includes a thermal oil-water cooler, an oil storage tank, a mechanical pump, a cold trap and a thermal oil-water cooler, etc., and the gas circuit includes an argon gas bottle group, a melting tank, an expansion tank and a lithium-lead storage tank. The lithium-lead loop is connected to the thermal oil loop through the lithium-lead-thermal oil cooler, and the thermal oil loop is connected to the cooling water loop through the thermal oil-water cooler.

[0007] Furthermore, in order to prevent lithium lead from reacting with water, a heat transfer oil circuit is arranged between the lithium lead circuit and the cooling water circuit. The liquid lithium lead is heated in the lithium lead system and transfers the heat to the heat transfer oil circuit, and the heat transfer oil finally transfers the heat to the cooling water circuit.

[0008] Furthermore, the lithium-lead circuit is divided into three branches at the outlet of the second mechanical pump. The lithium-lead in branch one increases in temperature after flowing through the heater and the experimental section, and then is mixed with the low-temperature lithium-lead in branch two and branch three in the primary mixer and the secondary mixer respectively to cool down, and finally flows into the lithium-lead-thermal oil cooler.

[0009] Furthermore, the branch where the lithium lead flows through the heater, the experimental section and the primary mixer is the high-temperature section of the experimental loop, and high-temperature resistant materials are used as pipes. The high-temperature resistant materials are nickel-based alloys, 316h or 310s. The other parts are low-temperature sections, and 316L stainless steel is used as pipes.

[0010] Furthermore, the superconducting magnet uses liquid helium cooling coils to maintain its superconducting properties and provide a strong magnetic field environment for the experimental section; there are two channels in the horizontal and vertical directions inside the superconducting iron, and the experimental section is placed in the channels to study the flow and heat transfer characteristics of liquid lithium-lead under the coupling of magnetic field and gravitational field.

[0011] Furthermore, the design of the experimental section covers the complex geometric features of the advanced blanket of the fusion reactor, including straight channels, parallel multi-channels, sudden expansion / contraction, gradual expansion / contraction and curved pipes; the surface of the experimental section is covered with a heating plate to achieve single-sided or four-sided circumferential heating, which is used to study the flow heat transfer characteristics of high Graschev numbers under a large heat source.

[0012] Furthermore, the regenerator is used as a waste heat recovery device, which adopts a sleeve type, and the high-temperature lithium lead flows through the tube side, and the low-temperature lithium lead flows through the shell side; a heating wire is wrapped around the outer tube wall of the regenerator to prevent the lithium lead in the inner and outer tubes from solidifying and blocking the flow channel, thereby hindering the safe operation of the experimental loop.

[0013] Furthermore, the lithium-lead-oil cooler adopts a vertical tube-in-tube type, high-temperature lithium-lead flows through the tube side, and heat-conducting oil flows through the shell side to save lithium-lead consumption, and after the experiment, the lithium-lead is smoothly discharged into the lithium-lead storage tank under the action of gravity.

[0014] Furthermore, the cold trap adopts a heat exchanger with a built-in metal wire mesh, which is placed in the bypass downstream of the lithium-lead-thermal oil cooler. A small amount of high-temperature lithium-lead is introduced from the lithium-lead circuit to flow into the primary side of the cold trap, and a small amount of low-temperature thermal oil is introduced from the thermal oil circuit to flow into the secondary side of the cold trap for heat exchange. After the high-temperature lithium-lead is cooled, metal and non-metallic impurities are precipitated and captured by the metal wire mesh.

[0015] Furthermore, the first, second and third mechanical pumps all adopt a vertical "cantilever + shaft seal" form, which can avoid dry friction between the bearing and the lithium lead, increase the service life, and ensure that the lithium lead will not leak.

[0016] Furthermore, the heater adopts an inserted rod bundle for heating, and lithium lead flows into the heater and flushes the rod bundle for heat exchange, thereby increasing the outlet temperature at a large flow rate.

[0017] Furthermore, the gas circuit includes an argon gas cylinder group, a vacuum pump, pipelines and valves. Before the experimental loop is operated, the argon gas cylinder group and the vacuum pump work together to discharge the air in the lithium-lead pipeline and the equipment through loop purge to prevent the reaction between air and lithium-lead. Thereafter, the lithium-lead storage tank is filled with argon gas to pressurize the lithium-lead from the lithium-lead storage tank to fill the entire lithium-lead loop.

[0018] Furthermore, differential pressure transmitters are arranged at the inlet and outlet of the experimental section. Due to the high working temperature of lithium-lead, a drainage cooling method is used to measure the pressure drop to protect the integrity of the measurement and control instrumentation.

[0019] Furthermore, a liquid level gauge is arranged in the lithium-lead storage tank and the expansion tank, and the liquid level is used to judge whether the lithium-lead has filled and emptied the entire lithium-lead circuit, which is helpful to carry out and stop the experiment in time.

[0020] Furthermore, a heating system is arranged on the pipelines, heaters, regenerators, mixers, valves and lithium-lead-thermal oil coolers of the lithium-lead loop. The heating power is adjusted by a power control cabinet to control the pipe wall temperature to be higher than the melting point of lithium-lead, so as to avoid the solidification of lithium-lead and blockage of the flow channel, which affects the safe operation of the experimental loop.

[0021] Compared with the existing magnetic fluid experimental circuit, the present invention has the following beneficial effects:

[0022] 1. The design temperature, flow rate, magnetic field strength and experimental section size of the high-temperature magnetic fluid experimental loop of the present invention are close to the actual working conditions of the advanced blanket of the fusion reactor. In addition, under a relatively high magnetic field environment, the experimental loop directly uses lithium lead as the circulating working fluid, and there is no need to use liquid metals with high conductivity, such as mercury, lithium, NaK, GaInSn, etc. to replace lithium lead in order to achieve a high Ha number. Therefore, the high-temperature magnetic fluid loop of the present invention can provide real and reliable experimental data for the design of the fusion reactor blanket.

[0023] 2. The high-temperature magnetic fluid experimental loop of the present invention has horizontal and vertical experimental section channels inside the superconducting magnet, and the surface of the experimental section is covered with heating plates, which can achieve single-sided and circumferential heating. Therefore, the high-temperature magnetic fluid experimental loop of the present invention is fully functional and can study the magnetic fluid characteristics of the advanced blanket of the fusion reactor under the coupling of multiple physical fields such as magnetic field, gravity field, thermal field and flow field. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a process flow chart of a high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research of the present invention;

[0025] Figure 2 The present invention is a design diagram of an experimental section of a high-temperature magnetic fluid experimental loop suitable for advanced blanket research of fusion reactors.

[0026] In the figure: 1. lithium-lead circuit; 2. thermal oil circuit; 3. cooling water circuit; 4. gas circuit; 5. argon cylinder group; 6. vacuum pump; 7. oil storage tank; 8-1. first mechanical pump; 8-2. second mechanical pump; 8-3. third mechanical pump; 9. cold trap; 10. lithium-lead-thermal oil cooler; 11. thermal oil-water cooler; 12. melting tank; 13. lithium-lead storage tank; 14. expansion tank; 15. heater; 16. superconducting magnet; 17. experimental section; 18. primary mixer; 19. regenerator; 20. secondary mixer; 21. cooling tower; 22. valve; 23. experimental section pipe wall; 24-1. first heating plate; 24-2. second heating plate; 24-3. third heating plate; 24-4. fourth heating plate. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0028] like Figure 1 As shown, the high-temperature magnetic fluid experimental circuit suitable for the research of advanced blanket of fusion reactor of the present invention adopts lithium-lead alloy as circulating working fluid, including lithium-lead circuit 1, thermal oil circuit 2, cooling water circuit 3 and gas circuit 4, through heater 15, superconducting magnet 16, experimental section 17, primary mixer 18, regenerator 19, secondary mixer 20, lithium-lead-thermal oil cooler 10, thermal oil-water cooler 11, cold trap 9, expansion tank 14, melting tank 12, lithium-lead storage tank and first mechanical pump 8-1, second mechanical pump 8-2, third mechanical pump 8-3 and other components to provide necessary experimental conditions for the research of key scientific issues of advanced blanket of fusion reactor.

[0029] The lithium-lead loop 1 includes a heater 15, a superconducting magnet 16, an experimental section 17, a primary mixer 18, a regenerator 19, a lithium-lead-thermal oil cooler 10, a cold trap 9, an expansion tank 14, a melting tank 12, a lithium-lead storage tank 13, and a second mechanical pump 8-2. The thermal oil loop 2 includes a thermal oil-water cooler 11, an oil storage tank 7, a first mechanical pump 8-1, a cold trap 9, and a thermal oil-water cooler 11. The gas circuit 4 includes an argon gas bottle group 5, a melting tank 12, an expansion tank 14, and a lithium-lead storage tank 13. The cooling water loop 3 includes a cooling tower 21. The lithium-lead loop 1 is connected to the thermal oil loop 2 through the lithium-lead-thermal oil cooler 10, and the thermal oil loop 2 is connected to the cooling water loop 3 through the thermal oil-water cooler 11.

[0030] Before the experimental loop is operated, the argon cylinder group 5 and the vacuum pump 6 work together to exhaust the air in the lithium-lead loop 1 by loop purge to prevent the reaction between air and lithium-lead. Then, the lithium-lead storage tank 13 is filled with argon gas to pressurize the lithium-lead from the lithium-lead storage tank 13 to fill the entire lithium-lead loop.

[0031] In order to prevent lithium lead from reacting with water, the experimental loop is provided with a heat transfer oil loop 2 between the lithium lead loop 1 and the cooling water loop 3. The liquid lithium lead is heated in the lithium lead loop 1 and transfers the heat to the heat transfer oil loop 2, and the heat transfer oil finally transfers the heat to the cooling water loop 3. The lithium lead loop 1 is divided into three branches at the outlet of the second mechanical pump 8-2. The lithium lead in branch 1 rises in temperature after flowing through the heater 15 and the experimental section 17, and then mixes with the low-temperature lithium lead in branch 2 and branch 3 in the primary mixer 18 and the secondary mixer 20 to cool down, and finally flows into the lithium lead-heat transfer oil cooler 10. The branch where the lithium lead flows through the heater 15, the experimental section 17 and the primary mixer 18 is the high-temperature section of the experimental loop, and high-temperature resistant materials are used as pipes, such as nickel-based alloys, 316h or 310s, etc. The other parts are low-temperature sections, and 316L stainless steel is used as pipes. A heating system is arranged on the pipelines and equipment of the lithium-lead loop 1. The heating power is adjusted by the power control cabinet to control the pipe wall temperature to be higher than the melting point of lithium-lead, so as to avoid the solidification of lithium-lead to block the flow channel and affect the safe operation of the experimental loop.

[0032] The first mechanical pump 8-1, the second mechanical pump 8-2 and the third mechanical pump 8-3 all adopt a vertical "cantilever + shaft seal" form, which can avoid dry friction between the bearing and the lithium lead, increase the service life, and ensure that the lithium lead will not leak.

[0033] The cold trap 9 is a heat exchanger with a built-in metal wire mesh, which is placed in the bypass downstream of the lithium-lead-thermal oil cooler 10. A small amount of high-temperature lithium-lead is introduced from the lithium-lead circuit 1 to flow into the primary side of the cold trap 9, and a small amount of low-temperature thermal oil is introduced from the thermal oil circuit 2 to flow into the secondary side of the cold trap 9 for heat exchange. After the high-temperature lithium-lead is cooled, metal and non-metal impurities are precipitated and captured by the metal wire mesh.

[0034] The lithium lead-thermal oil cooler 10 adopts a vertical tube-type design, with high-temperature lithium lead flowing on the tube side and thermal oil flowing on the shell side. This design can save lithium lead consumption, and after the experiment is over, the lithium lead can be smoothly discharged into the lithium lead storage tank 13 under the action of gravity.

[0035] Liquid level gauges are arranged in the lithium-lead storage tank 13 and the expansion tank 14, and the liquid levels can be used to determine whether the lithium-lead circuit is fully filled or emptied, which helps to start and stop the experiment in time.

[0036] The heater 15 is heated by an inserted rod bundle. Lithium and lead flow into the heater 15 and flush the rod bundle for heat exchange, so a higher outlet temperature can be achieved at a large flow rate.

[0037] The superconducting magnet 16 uses liquid helium cooling coils to maintain its superconducting properties and provide a strong magnetic field environment for the experimental section. The superconducting magnet 16 has two channels in the horizontal and vertical directions. The experimental section 17 is placed in the channels to study the flow and heat transfer characteristics of liquid lithium-lead under the coupling of magnetic field and gravity field.

[0038] The inlet and outlet of the experimental section 17 are equipped with differential pressure transmitters. Due to the high operating temperature of lithium-lead, the pressure drop is measured by drainage cooling method to protect the integrity of the measurement and control instruments. The design of the experimental section 17 covers the complex geometric features of the advanced blanket of the fusion reactor, including straight channels, parallel multi-channels, sudden expansion / contraction, gradual expansion / contraction, and curved pipes. The surface of the experimental section 17 is covered with a heating plate to achieve single-sided or four-sided circumferential heating, which can be used to study the flow heat transfer characteristics of high Grashof number under large heat sources. Figure 2 As shown, the four sides of the experimental section tube wall 23 of the experimental section 17 are covered with a first heating plate 24-1, a second heating plate 24-2, a third heating plate 24-3, and a fourth heating plate 24-4. The power of each heating plate can be independently controlled to achieve single-sided or circumferential four-sided heating. The flow and heat transfer characteristics of liquid lithium-lead with high Hartmann number (Gr) under the coupling of multiple physical fields such as magnetic field, thermal field, gravity field and flow field can be studied, providing real and reliable experimental data for the design of advanced blanket of fusion reactor.

[0039] The regenerator 19 is a waste heat recovery device, which can improve the economy of the lithium-lead loop 1 and reduce costs. The regenerator 19 adopts a sleeve type, with high-temperature lithium-lead flowing on the tube side and low-temperature lithium-lead flowing on the shell side. Due to its compact structure, the heating wire is wound on the outer tube wall to prevent the lithium-lead in the inner and outer tubes from solidifying and blocking the flow channel, which hinders the safe operation of the experimental loop.

[0040] The specific process flow of the high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research of the present invention is as follows:

[0041] (1) Before the experiment begins, the lithium-lead loop 1 is filled and exhausted by the argon gas bottle group 5 and the vacuum pump 6 to completely remove the oxygen in the pipeline to prevent it from reacting with the lithium-lead;

[0042] (2) The oil storage tank 7 heats the heat transfer oil, and when the temperature rises above the melting point of lithium lead, the first mechanical pump 8-1 is turned on to operate the heat transfer oil circuit 2;

[0043] (3) Lithium-lead working fluid is put into the melting tank 12 and flows into the lithium-lead storage tank 13, and then the lithium-lead storage tank 13 is pressurized by the argon gas cylinder group 5 to press the lithium-lead into the lithium-lead circuit 1, and it is judged according to the liquid level of the expansion tank 14 that the lithium-lead has filled the entire lithium-lead circuit 1;

[0044] (4) The second mechanical pump 8-2 of the lithium-lead loop 1 is turned on, and its outlet is divided into three branches. After the branch 1 flows through the heater 15, the temperature is raised to the experimental condition, and then the branches flow into the experimental sections 17 arranged horizontally and vertically in the superconducting magnet 16 respectively;

[0045] (5) After the lithium lead flows out of the experimental section 17, it flows through the primary mixer 18, the regenerator 19 and the secondary mixer 20 in sequence, exchanges heat with the low-temperature lithium lead in the branch 2 and the branch 3, and then transfers heat to the thermal oil circuit 2 in the lithium lead-thermal oil cooler 10;

[0046] (6) The cold trap 9 is placed in the bypass downstream of the lithium-lead-thermal oil cooler 10, and a small amount of high-temperature lithium-lead is introduced from the lithium-lead circuit 1 to flow into the primary side of the cold trap 9, and a small amount of low-temperature thermal oil is introduced from the thermal oil circuit 2 to flow into the secondary side of the cold trap 9 for heat exchange. After the high-temperature lithium-lead is cooled, metal and non-metal impurities are precipitated and captured by the built-in metal wire mesh;

[0047] (7) The heat transfer oil flows through the heat transfer oil-water cooler 11 to transfer heat to the cooling water circuit 3. After the cooling water is heated, it is cooled by the cooling tower 21 to complete the closed thermal system cycle;

[0048] (8) The flow rates of the lithium-lead circuit 1, the heat transfer oil circuit 2, the cooling water circuit 3 and the gas circuit 4 are adjusted by valve 22.

[0049] (9) By adjusting the power of the heater 15, the opening of the valve 22, and the frequency of the mechanical pump, liquid lithium-lead at different flow rates and temperatures can be obtained at the inlet of the experimental section.

[0050] The parts of the present invention not described in detail belong to the common knowledge in the art.

[0051] Although the above content describes the illustrative specific embodiments of the present invention to facilitate the understanding of the present invention by those skilled in the art, it should be clear that the present invention is not limited to the scope of the specific embodiments, and it is obvious to those skilled in the art that various changes are within the spirit and scope of the appended claims and the present invention, and are all protected by the present invention.

Claims

1. A high-temperature magnetic fluid experimental loop suitable for advanced blanket research of fusion reactors, characterized by: Lithium-lead alloy is used as a circulating working fluid, and the experimental circuit includes a lithium-lead circuit, a thermal oil circuit, a cooling water circuit and a gas circuit; wherein the lithium-lead circuit includes a heater, a superconducting magnet, an experimental section, a primary mixer, a regenerator, a lithium-lead-thermal oil cooler, a cold trap, an expansion tank, a melting tank, a lithium-lead storage tank and a second mechanical pump, the thermal oil circuit includes a lithium-lead-thermal oil cooler, an oil storage tank, a first mechanical pump, a cold trap and a thermal oil-water cooler, and the gas circuit includes an argon gas bottle group, a melting tank, an expansion tank and a lithium-lead storage tank; the cooling water circuit includes a cooling tower; the lithium-lead circuit is connected to the thermal oil circuit through the lithium-lead-thermal oil cooler, and the thermal oil circuit is connected to the cooling water circuit through the thermal oil-water cooler; The lithium-lead loop is divided into three branches at the outlet of the second mechanical pump. The lithium-lead in branch one increases in temperature after flowing through the heater and the experimental section, and then is mixed with the low-temperature lithium-lead in branch two and branch three in the primary mixer and the secondary mixer respectively to reduce in temperature, and finally flows into the lithium-lead-thermal oil cooler; The superconducting magnet uses liquid helium to cool the coil to maintain its superconducting properties and provide a strong magnetic field environment for the experimental section. The superconducting magnet has two channels in the horizontal and vertical directions. The experimental section is placed in the channels to study the flow and heat transfer characteristics of liquid lithium-lead under the coupling of magnetic field and gravitational field. The cold trap uses a heat exchanger with a built-in metal wire mesh, which is placed in the bypass downstream of the lithium-lead-thermal oil cooler. A small amount of high-temperature lithium-lead is introduced from the lithium-lead circuit to flow into the primary side of the cold trap, and a small amount of low-temperature thermal oil is introduced from the thermal oil circuit to flow into the secondary side of the cold trap for heat exchange. After the high-temperature lithium-lead is cooled, metal and non-metal impurities are precipitated and captured by the metal wire mesh.

2. A high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: In order to prevent lithium lead from reacting with water, a heat transfer oil circuit is arranged between the lithium lead circuit and the cooling water circuit. The liquid lithium lead is heated in the lithium lead circuit and transfers the heat to the heat transfer oil circuit, and the heat transfer oil finally transfers the heat to the cooling water circuit.

3. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: The branch where lithium lead flows through the heater, experimental section and primary mixer is the high-temperature section of the experimental loop, and high-temperature resistant materials are used as pipes. The high-temperature resistant materials are nickel-based alloys, 316h or 310s. The other parts are low-temperature sections and 316L stainless steel is used as pipes.

4. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: The design of the experimental section covers the complex geometric features of the advanced blanket of the fusion reactor, which include straight channels, parallel multi-channels, sudden expansion / contraction, gradual expansion / contraction, and curved pipes; a heating plate is covered on the surface of the experimental section to achieve single-sided or four-sided circumferential heating, which is used to study the flow and heat transfer characteristics of high Graschev numbers under a large heat source.

5. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: The regenerator is a waste heat recovery device, which adopts a sleeve type. High-temperature lithium lead flows through the tube side, and low-temperature lithium lead flows through the shell side. A heating wire is wound around the outer tube wall of the regenerator to prevent the lithium lead in the inner and outer tubes from solidifying and blocking the flow channel, thereby hindering the safe operation of the experimental loop.

6. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: The lithium-lead-oil cooler adopts a vertical tube-type, high-temperature lithium-lead flows through the tube side, and heat-conducting oil flows through the shell side to save lithium-lead consumption. After the experiment, the lithium-lead is smoothly discharged into the lithium-lead storage tank under the action of gravity.

7. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: The first and second mechanical pumps both adopt a vertical "cantilever + shaft seal" form to avoid dry friction between the bearing and the lithium lead, increase the service life, and ensure that the lithium lead will not leak.

8. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: The heater is heated by an inserted rod bundle, and lithium lead flows into the heater and flushes the rod bundle for heat exchange, thereby increasing the outlet temperature at a large flow rate.

9. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: Before the experimental loop is operated, the argon cylinder group and the vacuum pump work together to exhaust the air in the lithium-lead pipeline and the equipment by loop purge to prevent the reaction between air and lithium-lead. Then, the lithium-lead storage tank is filled with argon gas to pressurize the lithium-lead from the lithium-lead storage tank to fill the entire lithium-lead loop.

10. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: Differential pressure transmitters are arranged at the inlet and outlet of the experimental section. Due to the high working temperature of lithium-lead, the drainage cooling method is adopted to measure the pressure drop to protect the integrity of the measurement and control instrument.

11. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: Liquid level gauges are arranged in the lithium-lead storage tank and the expansion tank, and the liquid levels are used to judge whether the lithium-lead circuit is fully filled or emptied, which helps to carry out and stop the experiment in time.

12. The high-temperature magnetic fluid experimental loop suitable for fusion reactor advanced blanket research according to claim 1, characterized in that: A heating system is arranged on the pipeline, heater, regenerator, primary mixer, valve and lithium-lead-thermal oil cooler of the lithium-lead loop. The heating power is adjusted by the power control cabinet to control the pipe wall temperature to be higher than the melting point of lithium-lead, so as to avoid the solidification of lithium-lead to block the flow channel and affect the safe operation of the experimental loop.

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