A comprehensive experimental system and method for heat transfer in high-temperature gas flow

Abstract

This invention discloses a comprehensive experimental system and method for high-temperature gas flow heat transfer. The experimental system includes a gas supply system, a gas supply regulation and measurement system, a test section preheating system, a test section system, a pressure stabilization system, and a tail gas treatment system. This invention utilizes gases such as hydrogen, helium, and nitrogen as experimental working fluids, and employs high-power electromagnetic induction heating elements to conduct material property and failure tests under various operating conditions. Steady-state and transient tests of flow heat transfer in single channels and components are also performed. This completes the study of the heat transfer mechanism of variable-property gas working fluids flowing through an internal heat source in a component channel under high temperature and high heat flux density conditions.

Description

Technical Field

[0001] This invention relates to an experimental loop design scheme in the field of nuclear industry applications and scientific research, specifically to a comprehensive experimental system and method for high-temperature gas flow heat transfer. Background Technology

[0002] Experimentation is essential for verifying the correctness of theories and provides a feasible basis for technological development. With continuous technological advancements, the requirements for experimental equipment are becoming increasingly stringent. Conventional low-temperature and atmospheric-pressure tests can no longer meet practical needs; experimental equipment and circuits under high-temperature and high-pressure environments have become new design objectives. To study the heat transfer mechanism of variable-property gaseous working fluids flowing through element channels with internal heat sources under high-temperature and high-heat-fluidity conditions, an advanced experimental testing device is needed to evaluate the heat transfer characteristics of candidate fluid working fluids. Because high-temperature and high-pressure experiments are accompanied by significant risks, the design of the experimental device should fully consider safety and redundancy principles to ensure the safety of high-temperature gas experiments. Summary of the Invention

[0003] In order to overcome the problems existing in the prior art, the purpose of this invention is to provide a comprehensive experimental system and method for high-temperature gas flow heat transfer, which can simulate the power, flow rate and temperature conditions encountered by nuclear fuel elements (or some elements) according to the experimental purpose, and be used to evaluate the design and manufacturing materials of various nuclear fuel elements, and complete the study of the heat transfer mechanism of the fuel element channel flowing through the heat source in the zone under high temperature and high heat flux density conditions.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A high-temperature gas flow heat exchange integrated experimental system, the experimental system comprising a gas supply system, a gas supply regulation and measurement system, a test section preheating system, a test section system, a pressure stabilizing system, and an exhaust gas treatment system;

[0006] The gas supply system includes three branches: a cooling gas supply branch consisting of parallel nitrogen cylinders 1, a hydrogen-helium gas supply branch consisting of parallel hydrogen cylinders 2 and parallel helium cylinders 3 connected in parallel, and an air-nitrogen gas supply branch consisting of parallel nitrogen cylinders 4, an air compressor 5, and an air storage tank 6; wherein the cooling gas supply branch supplies nitrogen to the pressure vessel 56 through nitrogen cylinders 1, discharges other gas impurities, maintains the actual pressure inside the pressure vessel (56) higher than the highest gas pressure inside the test section 59, prevents the experimental gas from leaking out, and serves as a cooling effect for the ambient gas; the hydrogen-helium gas supply branch and the air-nitrogen gas supply branch provide a stable high-pressure working medium for the test section 59;

[0007] The gas supply regulation and measurement system comprises three parts. The regulation and measurement system for the cooling gas supply branch consists of a first pressure reducing valve 7, a first shut-off valve 12, a sixth shut-off valve 17, a sixth flow meter 36, a seventh shut-off valve 18, a first check valve 40, and a first rotary regulating valve 46, sequentially installed on the pipeline connecting the parallel nitrogen cylinder 1 and the pressure vessel 56. The regulation and measurement system for the hydrogen-helium gas supply branch consists of a second pressure reducing valve 8 and a second shut-off valve 13, sequentially installed after the parallel hydrogen cylinder 2, a third pressure reducing valve 9 and a third shut-off valve 14, and an eighth shut-off valve 19, a first pressure sensor 30, a second flow meter 37, and a ninth shut-off valve 20, sequentially installed on the pipeline connecting the hydrogen-helium gas supply branch and the test section flange 55. The system consists of a second check valve 41, a tenth shut-off valve 21, and a second rotary regulating valve 47; the regulating and measuring system of the air-nitrogen supply branch consists of a fourth pressure reducing valve 10 and a fourth shut-off valve 15 installed sequentially after the parallel nitrogen cylinder 4, a fifth pressure reducing valve 11 and a fifth shut-off valve 16 installed sequentially after the air storage tank 6, and an eleventh shut-off valve 22, a second pressure sensor 31, a third flow meter 38, a twelfth shut-off valve 23, a third check valve 42, a thirteenth shut-off valve 24, and a third rotary regulating valve 48 on the pipeline connecting the air-nitrogen supply branch to the gas preheater 54; the parallel gas cylinder is filled with high-pressure gas working medium, the pressure reducing valve adjusts the gas to the parameters required for the experiment, the regulating valve changes the gas flow rate, and the gas flow rate is measured by the gas flow meter;

[0008] The test section preheating system consists of a gas preheater 54, a test section front flange 55, and a fourteenth shut-off valve 25, a fourth flow meter 39, a fifteenth shut-off valve 26, a fourth check valve 43, a sixteenth shut-off valve 27, and a fourth rotary regulating valve 49 sequentially installed on the pipelines connected to it. The gas preheater 54 is equipped with a first thermocouple 50, a third pressure sensor 32, a second thermocouple 51, and a fourth pressure sensor 33 at its inlet and outlet, respectively, for measuring the gas temperature and pressure at the inlet and outlet of the gas preheater 54.

[0009] The test section system consists of a pressure vessel 56, an electromagnetic induction heater 58, an induction coil liquid cooling device 57, a test section 59, and a gas cooling long pipe 61. The test section 59 is placed inside the pressure vessel 56 and is connected to the front and rear pipelines through the front flange 55 and the rear flange 60 of the test section, respectively. The electromagnetic induction heater 58 and the induction coil liquid cooling device 57 heat and cool the test section 59, respectively. The test section 59 is fitted inside the pressure vessel and directly filled with heat insulation material. A third thermocouple 52 and a fifth pressure sensor 34 are installed on the pressure vessel 56 by welding to monitor the temperature and pressure changes inside the pressure vessel.

[0010] The pressure stabilization system of the test section consists of the seventeenth shut-off valve 28 on the pipeline connecting the pressure vessel 56 and the vacuum pump 63, the vacuum pump 63, the eighteenth shut-off valve 29 after the vacuum pump 63, and the sixth check valve 45. Before the experiment starts, the pressure vessel 56 is evacuated by the vacuum pump 63. Nitrogen is supplied to the pressure vessel 56 through the nitrogen cylinder 1 from the cooling gas supply branch. The vacuum pump 63 and the nitrogen cylinder 1 are adjusted to maintain the actual pressure in the pressure vessel 56 higher than the highest gas pressure in the test section to prevent the experimental gas from leaking out. The vacuum pump 63 generates a stable airflow to carry away some of the heat dissipated due to the heating of the test piece.

[0011] The exhaust gas treatment system consists of three parts: a first exhaust gas treatment system consisting of the downstream section of the gas cooling long pipe 61 and the fifth check valve 44, the fourth thermocouple 53, the pressure reducing valve 62 after the gas cooling long pipe, the sixth pressure sensor 35, the first flame arrester 65, and the third foreign object shielding device 70 arranged sequentially on the pipe; a second exhaust gas treatment system consisting of the downstream section of the vacuum pump 63 and the flame arrester 66 and the foreign object shielding device 69; and a third exhaust gas treatment system consisting of the connection pipe between the foreign object shielding device 68 and the pressure vessel 56 and the safety valve 64 and the flame arrester 67 arranged sequentially on the pipe. The cooled and depressurized gas flows through the first flame arrester 65, the second flame arrester 66, the third flame arrester 67, the third foreign object filter device 70, the second foreign object shielding device 69, and the first foreign object shielding device 68 before being discharged into the atmosphere.

[0012] Depending on the experimental purpose, different materials are selected for the test section 59. When conducting the corrosion durability verification test of hydrogen on the test section 59, tungsten tubes are selected as the test material. When conducting the corrosion durability verification test of air on the test section 59, ODS steel is used as the test material. When conducting the flow heat transfer test of the channel, ceramic test pieces are used.

[0013] The high-pressure working gas is hydrogen or nitrogen, which are harmless to the environment; the circuit pipeline is made of standard 316L stainless steel.

[0014] The air and nitrogen in the air-nitrogen branch are heated to 600K by a gas preheater (54) for subsequent experiments, while hydrogen and helium are directly heated.

[0015] The electromagnetic induction heater 58 is configured in zones, and its heating power is controlled separately by an electrical control cabinet to simulate the uneven power distribution of an actual reactor. Material property and failure tests, as well as steady-state and transient tests of flow heat transfer, are carried out under various operating conditions. To protect the heating coil, it is necessary to cool the heating coil through the induction coil liquid cooling device 57. To prevent heat loss, a high-temperature resistant insulating coating is required to be applied to the heated test piece. For test sections made of non-metallic materials, a heating auxiliary part should be added, and a thin layer of tungsten metal should be added to the outside of the test section.

[0016] The gas cooling tube 61 is used to cool the heated experimental gas. The gas flowing out of the test section still has a high temperature. By passing through the gas cooling tube 61 outside the pressure vessel 56, the high-temperature gas—gas cooling tube 61—room temperature air can be cooled by convection, which facilitates subsequent data acquisition and measurement.

[0017] The sensing element of the electromagnetic induction heater 58 is a spiral tube.

[0018] The high-temperature gas flow heat transfer integrated experimental system of the present invention has the following characteristics:

[0019] 1. The test section 59 can be expanded by combining several branches and test section connections in the system according to specific experimental needs. It mainly includes steady-state / transient flow heat transfer experiments and material durability tests to test and evaluate different types of reactor core fuel elements.

[0020] 2. The test section is placed inside the pressure vessel 56 and nitrogen is introduced as the ambient gas to maintain the actual pressure inside the pressure vessel 56 higher than the maximum gas pressure inside the test section 59, so as to prevent hydrogen leakage in the coolant channel due to insufficient contact between the interface of the test section 59 and the hydrogen delivery pipeline.

[0021] 3. The test section 59 is heated in zones by electromagnetic induction heater 58, and the power distribution in different zones is controlled separately.

[0022] 4. A gas cooling pipe 61 is added to the high-temperature zone of the main circuit after the test section. The high-temperature gas is cooled by the convection of the high-temperature gas, the gas cooling pipe 61, and the room temperature air to meet the working temperature of the measuring instruments in the downstream section and facilitate the acquisition of experimental data. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the high-temperature gas flow heat exchange integrated experimental system of the present invention.

[0024] In the diagram: 1. Nitrogen cylinder; 2. Hydrogen cylinder; 3. Helium cylinder; 4. Nitrogen cylinder in the air-nitrogen branch; 5. Air compressor; 6. Air storage tank; 7. First pressure reducing valve; 8. Second pressure reducing valve; 9. Third pressure reducing valve; 10. Fourth pressure reducing valve; 11. Fifth pressure reducing valve; 12. First shut-off valve; 13. Second shut-off valve; 14. Third shut-off valve; 15. Fourth shut-off valve; 16. Fifth shut-off valve; 17. Sixth shut-off valve; 18. Seventh shut-off valve; 19. Eighth shut-off valve; 20. Ninth shut-off valve. Valve; 21. Tenth shut-off valve; 22. Eleventh shut-off valve; 23. Twelfth shut-off valve; 24. Thirteenth shut-off valve; 25. Fourteenth shut-off valve; 26. Fifteenth shut-off valve; 27. Sixteenth shut-off valve; 28. Seventeenth shut-off valve; 29. ​​Eighteenth shut-off valve; 30. First pressure sensor; 31. Second pressure sensor; 32. Third pressure sensor; 33. Fourth pressure sensor; 34. Fifth pressure sensor; 35. Sixth pressure sensor; 36. First flow meter; 3 7. Second flow meter; 38. Third flow meter; 39. Fourth flow meter; 40. First check valve; 41. Second check valve; 42. Third check valve; 43. Fourth check valve; 44. Fifth check valve; 45. Sixth check valve; 46. First rotary regulating valve; 47. Second rotary regulating valve; 48. Third rotary regulating valve; 49. Fourth rotary regulating valve; 50. First thermocouple; 51. Second thermocouple; 52. Third thermocouple; 53. Fourth thermocouple; 54. Gas preheating 55. Test section front flange; 56. Pressure vessel; 57. Electromagnetic induction coil liquid cooling device; 58. Electromagnetic induction heater; 59. Test section; 60. Test section rear flange; 61. Gas cooling long pipe; 62. Pressure reducing valve after gas cooling long pipe; 63. Vacuum pump; 64. Safety valve; 65. First flame arrester; 66. Second flame arrester; 67. Third flame arrester; 68. First foreign object shielding device; 69. Second foreign object shielding device; 70. Third foreign object shielding device. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and examples.

[0026] like Figure 1 As shown, the present invention provides a comprehensive experimental system for high-temperature gas flow heat exchange, characterized in that: the experimental system includes a gas supply system, a gas supply regulation and measurement system, a test section preheating system, a test section system, a pressure stabilization system, and an exhaust gas treatment system.

[0027] The gas supply system includes three branches: a cooling gas supply branch consisting of parallel nitrogen cylinders 1; a hydrogen-helium gas supply branch consisting of parallel hydrogen cylinders 2 and parallel helium cylinders 3 connected in parallel; and an air-nitrogen gas supply branch consisting of parallel nitrogen cylinders 4, an air compressor 5, and an air storage tank 6. The cooling gas supply branch supplies nitrogen to the pressure vessel 56 through nitrogen cylinders 1, expels other gaseous impurities, and maintains the actual pressure inside the pressure vessel 56 higher than the maximum pressure inside the test section 59, generally 30 kPa higher. This prevents hydrogen leakage in the coolant flow channel due to insufficient contact between the test piece and the hydrogen delivery pipeline. It also removes some of the heat dissipated due to the heating of the test piece, thus providing a cooling effect. The hydrogen-helium gas supply branch and the air-nitrogen gas supply branch provide a stable high-pressure working medium for the test section 59. Specifically, this is achieved by providing stable high-inlet-pressure hydrogen, helium, and nitrogen through parallel cylinders or by generating stable air through the air compressor 5 as the high-pressure working medium.

[0028] The gas supply regulation and measurement system comprises three parts. The regulation and measurement system for the cooling gas supply branch consists of a first pressure reducing valve 7, a first shut-off valve 12, a sixth shut-off valve 17, a sixth flow meter 36, a seventh shut-off valve 18, a first check valve 40, and a first rotary regulating valve 46, sequentially installed on the pipeline connecting the parallel nitrogen cylinder 1 and the pressure vessel 56. The regulation and measurement system for the hydrogen-helium gas supply branch consists of a second pressure reducing valve 8 and a second shut-off valve 13, sequentially installed after the parallel hydrogen cylinder 2, a third pressure reducing valve 9 and a third shut-off valve 14, and an eighth shut-off valve 19, a first pressure sensor 30, a second flow meter 37, and a ninth shut-off valve 20, sequentially installed on the pipeline connecting the hydrogen-helium gas supply branch and the test section flange 55. The system consists of a second check valve 41, a tenth shut-off valve 21, and a second rotary regulating valve 47. The regulating and measuring system of the air-nitrogen supply branch consists of a fourth pressure reducing valve 10 and a fourth shut-off valve 15 located after the parallel nitrogen cylinder 4, a fifth pressure reducing valve 11 and a fifth shut-off valve 16 located after the air storage tank 6, and an eleventh shut-off valve 22, a second pressure sensor 31, a third flow meter 38, a twelfth shut-off valve 23, a third check valve 42, a thirteenth shut-off valve 24, and a third rotary regulating valve 48 located on the pipeline connecting the air-nitrogen supply branch to the gas preheater 54. The parallel gas cylinder is filled with high-pressure gas working medium. The pressure reducing valve adjusts the gas to the parameters required for the experiment. The regulating valve changes the gas flow rate, which is measured by the gas flow meter.

[0029] The test section preheating system consists of a gas preheater 54, a test section front flange 55, and a fourteenth shut-off valve 25, a fourth flow meter 39, a fifteenth shut-off valve 26, a fourth check valve 43, a sixteenth shut-off valve 27, and a fourth rotary regulating valve 49 sequentially installed on the connected pipelines. The gas preheater 54 is equipped with a first thermocouple 50, a third pressure sensor 32, a second thermocouple 51, and a fourth pressure sensor 33 at its inlet and outlet, respectively, to measure the gas temperature and pressure at the inlet and outlet of the gas preheater 54. Simultaneously, due to safety concerns with the hydrogen preheater, it is proposed to directly heat the hydrogen and helium. Using thermocouples for steady-state temperature measurement improves accuracy, while using far-infrared thermometers for transient temperature measurement improves response speed.

[0030] The test section system consists of a pressure vessel 56, an electromagnetic induction heater 58, an induction coil liquid cooling device 57, a test section 59, and a gas cooling long pipe 61. The test section 59 is placed inside the pressure vessel 56 and is connected to the front and rear pipelines through the front flange 55 and the rear flange 60 of the test section, respectively. The electromagnetic induction heater 58 and the induction coil liquid cooling device 57 heat and cool the test section 59, respectively. The test section 59 is fitted inside and directly filled with heat insulation material. A third thermocouple 52 and a fifth pressure sensor 34 are installed on the pressure vessel 56 by welding to monitor the temperature and pressure changes inside the pressure vessel.

[0031] The pressure stabilization system of the test section consists of the seventeenth shut-off valve 28 on the pipeline connecting the pressure vessel 56 and the vacuum pump 63, the vacuum pump 63, the eighteenth shut-off valve 29 after the vacuum pump 63, and the sixth check valve 45. Before the experiment begins, the pressure vessel 56 is evacuated by the vacuum pump 63. Nitrogen is supplied to the pressure vessel 56 through the nitrogen cylinder 1 via the cooling gas supply branch. The vacuum pump 63 and the nitrogen cylinder 1 are adjusted to maintain the actual pressure inside the pressure vessel 56 higher than the highest gas pressure in the test section, preventing the experimental gas from leaking out. The vacuum pump 63 also generates a stable airflow to carry away some of the heat dissipated due to the heating of the test piece.

[0032] The exhaust gas treatment system consists of three parts: a first exhaust gas treatment system consisting of the downstream section of the gas cooling long pipe 61 and the fifth check valve 44, the fourth thermocouple 53, the pressure reducing valve 62 after the gas cooling long pipe, the sixth pressure sensor 35, the first flame arrester 65, and the third foreign object shielding device 70 arranged sequentially on the pipe; a second exhaust gas treatment system consisting of the downstream section of the vacuum pump 63 and the flame arrester 66 and the foreign object shielding device 69; and a third exhaust gas treatment system consisting of the connection pipe between the foreign object shielding device 68 and the pressure vessel 56 and the safety valve 64 and the flame arrester 67 arranged sequentially on the pipe. The cooled and depressurized gas flows through the first flame arrester 65, the second flame arrester 66, the third flame arrester 67, the third foreign object filter device 70, the second foreign object shielding device 69, and the first foreign object shielding device 68 before being discharged into the atmosphere.

[0033] Preferably, the cryogenic zone of the main circuit before the test section is divided into two parts: a hydrogen-helium branch and an air-nitrogen branch. At low flow rates, the high-pressure gas can achieve a relatively stable outlet pressure through the pressure reducing valve. Since hydrogen and helium have high heat capacity, the power required to heat them to the specified temperature at the same flow rate is high, and the thermal stress on the test piece is large. Therefore, a low-flow-rate experimental design is adopted. High-precision flow meters are installed in both the hydrogen-helium branch and the air-nitrogen branch of the cryogenic zone of the main circuit before the test section for flow measurement.

[0034] During the hydrogen corrosion durability verification test of tungsten tubes, the actual gas flow rate was increased by reducing the total inlet pressure, and the gas temperature was maintained at 600–1000 K. The durability of tungsten-based materials under high-speed hydrogen erosion was verified by long-term supply of high-speed, medium-temperature gas. The specific steps included:

[0035] 1) Before starting the experiment, check whether the valves of the experimental system are open, whether the instruments are in good condition, and whether the gas supply system has sufficient gas volume.

[0036] 2) Start vacuum pump 63 to evacuate pressure vessel 56;

[0037] 3) Purge nitrogen gas multiple times to fill pressure vessel 56;

[0038] 4) Adjust the pressure of vacuum pump 63 and parallel nitrogen cylinder 1 to maintain stable pressure inside pressure vessel 56;

[0039] 5) Open helium cylinder 3 and introduce helium into the hydrogen-helium branch to purge the air from the experimental system;

[0040] 6) Close helium cylinder 3, open hydrogen cylinder 2, introduce hydrogen into the hydrogen-helium branch for a preset time, and calibrate the reading of the second flow meter 37 to prevent gas leakage.

[0041] 7) Under conditions where hydrogen is not leaking, conduct a medium-low temperature experiment, ensuring the total gas outlet temperature does not exceed 800K, and calibrate the reading of the second flow meter 37.

[0042] 8) Gradually increase the power of the electromagnetic induction heater 58, repeat experimental step 6, and monitor the stability of the experimental system;

[0043] 9) After the power is increased to the specified power and the total temperature of the gas outlet reaches the experimental requirements, continue to observe for a preset time. After all parameters stabilize, carry out the corrosion durability verification test of hydrogen on test section 59.

[0044] 10) After the test, slowly reduce the power of the electromagnetic induction heater 58 to achieve slow cooling and avoid damage to the test section 59;

[0045] 11) After the power of the electromagnetic induction heater 58 drops to 0, hydrogen gas is continuously introduced to remove the residual heat of the experimental system.

[0046] 12) After the test section 59 has completely cooled down, open the helium cylinder 3 and continuously introduce helium to expel the test gas. Repeat this several times, then close the pipeline valve and keep the test pipeline sealed.

[0047] 13) Vacuum pump 63 is turned on to maintain pressure vessel 56 at atmospheric pressure;

[0048] 14) Collect data, then turn off the power to the data acquisition box.

[0049] The procedure for conducting the air corrosion durability verification test on test section 59 is as follows:

[0050] 1) Before starting the experiment, check whether the valves of the experimental system are open, whether the instruments are in good condition, and whether the gas supply system has sufficient gas volume.

[0051] 2) Start vacuum pump 63 to evacuate pressure vessel 56;

[0052] 3) Purge nitrogen gas multiple times to fill pressure vessel 56;

[0053] 4) Adjust the pressure of vacuum pump 63 and parallel nitrogen cylinder 1 to maintain stable pressure inside pressure vessel 56;

[0054] 5) Open nitrogen cylinder 4 and introduce nitrogen into the air-nitrogen branch to purge the air from the experimental system;

[0055] 6) Close nitrogen cylinder 4, turn on air compressor 5, introduce air into the air-nitrogen branch for a preset time, and calibrate the reading of the third flow meter 38 to prevent gas leakage;

[0056] 7) Turn on the gas preheater 54 to preheat the gas to 600K, and calibrate the reading of the fourth flow meter 39;

[0057] 8) Gradually increase the power of the electromagnetic induction heater 58. After the power is increased to the specified power and the total temperature of the gas outlet reaches the experimental requirements, continue to observe for a preset time. After all parameters are stable, carry out the corrosion durability verification test of air on test section 59.

[0058] 9) After the test, turn off the gas preheater 54 and slowly reduce the power of the electromagnetic induction heater 58 to achieve slow cooling and avoid damage to the test section 59.

[0059] 10) After the power of the electromagnetic induction heater 58 drops to 0, air is continuously introduced to remove the residual heat of the experimental system.

[0060] 11) After the test section 59 has completely cooled down, open nitrogen cylinder 1 and continuously introduce nitrogen to expel the test gas. Repeat this several times, then close the pipeline valve and keep the test pipeline sealed.

[0061] 12) Vacuum pump 63 is turned on to maintain pressure vessel 56 at normal pressure.

[0062] 13) Collect data, and then turn off the power to the data acquisition box.

[0063] When conducting flow heat transfer tests in the channel, the material of test section 59 is replaced with a ceramic test piece, and the experimental process is the same as the air corrosion durability verification test of test section 59.

Claims

1. An experimental method for a comprehensive experimental system for high-temperature gas flow heat transfer, characterized in that: The experimental system comprises a gas supply system, a gas supply adjustment and measurement system, a test section preheating system, a test section system, a test section pressure stabilizing system and a tail gas treatment system; The gas supply system comprises three branches: a cooling gas supply branch composed of a first parallel nitrogen cylinder (1), a hydrogen-helium gas supply branch composed of parallel hydrogen cylinders (2) and parallel helium cylinders (3) in parallel connection, and an air-nitrogen gas supply branch composed of a second parallel nitrogen cylinder (4), an air compressor (5) and an air storage tank (6); wherein the cooling gas supply branch provides nitrogen gas to the pressure vessel (56) through the first parallel nitrogen cylinder (1), discharges other gas impurities, maintains the actual pressure in the pressure vessel (56) higher than the maximum gas pressure in the test section (59), prevents experimental gas leakage, and plays a cooling role as an environmental gas; the hydrogen-helium gas supply branch and the air-nitrogen gas supply branch provide stable high-pressure gas working substance for the test section (59); The gas supply adjustment and measurement system comprises three parts: the adjustment and measurement system of the cooling gas supply branch is composed of a first pressure reducing valve (7), a first shut-off valve (12), a sixth shut-off valve (17), a sixth flowmeter (36), a seventh shut-off valve (18), a first check valve (40) and a first screw adjustment valve (46) arranged in sequence on the pipeline connecting the first parallel nitrogen cylinder (1) and the pressure vessel (56); the adjustment and measurement system of the hydrogen-helium gas supply branch is composed of a second pressure reducing valve (8) after the parallel hydrogen cylinders (2), a second shut-off valve (13), a third pressure reducing valve (9) after the parallel helium cylinders (3), a third shut-off valve (14), an eighth shut-off valve (19), a first pressure sensor (30), a second flowmeter (37), a ninth shut-off valve (20), a second check valve (41), a tenth shut-off valve (21) and a second screw adjustment valve (47) arranged in sequence on the pipeline connecting the hydrogen-helium gas supply branch and the test section front flange (55); the adjustment and measurement system of the air-nitrogen gas supply branch is composed of a fourth pressure reducing valve (10) after the second parallel nitrogen cylinder (4), a fourth shut-off valve (15), a fifth pressure reducing valve (11) after the air storage tank (6), a fifth shut-off valve (16), an eleventh shut-off valve (22), a second pressure sensor (31), a third flowmeter (38), a twelfth shut-off valve (23), a third check valve (42), a thirteenth shut-off valve (24) and a third screw adjustment valve (48) arranged in sequence on the pipeline connecting the air-nitrogen gas supply branch and the gas preheater (54); the parallel cylinders are filled with high-pressure gas working substance, the pressure reducing valves adjust the gas to the required parameters of the experiment, the adjustment valves are used to change the gas flow, and the gas flow is measured by the gas flowmeter; The test section preheating system is composed of a gas preheater (54), a test section front flange (55), and a fourteenth stop valve (25), a fourth flowmeter (39), a fifteenth stop valve (26), a fourth check valve (43), a sixteenth stop valve (27), and a fourth screwing regulating valve (49) arranged in sequence on a pipeline connecting the two; the gas preheater (54) is provided with a first thermocouple (50), a third pressure sensor (32), and a second thermocouple (51), a fourth pressure sensor (33) at the inlet and outlet thereof respectively for measuring the temperature and pressure of the gas at the inlet and outlet of the gas preheater (54); The test section system is composed of a pressure vessel (56), an electromagnetic induction heater (58), an induction coil liquid cooling device (57), a test section (59), and a gas cooling long pipe (61); the test section (59) is arranged in the pressure vessel (56) and connected with the front and rear pipelines through a test section front flange (55) and a test section rear flange (60); the electromagnetic induction heater (58) and the induction coil liquid cooling device (57) are used for heating and cooling the test section (59) respectively; the test section (59) is sleeved in the electromagnetic induction heater (58) and the induction coil liquid cooling device (57) and filled with a heat insulation material between the test section (59) and the electromagnetic induction heater (58) and the induction coil liquid cooling device (57); the pressure vessel (56) is provided with a third thermocouple (52) and a fifth pressure sensor (34) by welding for monitoring the temperature and pressure changes in the pressure vessel; The test section pressure stabilizing system is composed of a seventeenth stop valve (28), a vacuum pump (63), a sixteenth stop valve (29), and a sixth check valve (45) on a connecting pipeline of the pressure vessel (56) and the vacuum pump (63); before the experiment, the pressure vessel (56) is vacuumized by the vacuum pump (63); nitrogen is supplied to the pressure vessel (56) from a first parallel nitrogen cylinder (1) through a cooling gas supply branch; the vacuum pump (63) and the first parallel nitrogen cylinder (1) are adjusted to maintain the actual pressure in the pressure vessel (56) higher than the maximum gas pressure in the test section, prevent the experimental gas from leaking out, and generate a stable gas flow by the vacuum pump (63) to take away part of the heat dissipated due to heating of the test piece; The experimental method comprises: when a hydrogen corrosion durability verification test on a tungsten tube is performed, the actual gas flow rate is increased by reducing the inlet total pressure, the gas temperature is maintained at 600-1000K, the durability of tungsten-based materials under high-speed hydrogen gas scouring is verified by long-term supply of high-speed medium-temperature gas, and specifically comprises the following steps: 1) Before the experiment, check whether the valves of the experimental system are opened, whether the states of the instruments and apparatuses are good, and whether the gas amount of the gas supply system is sufficient; 2) Start the vacuum pump (63) to vacuumize the pressure vessel (56); 3) Fill the pressure vessel (56) with nitrogen; 4) Adjust the pressures of the vacuum pump (63) and the first parallel nitrogen cylinder (1) to maintain the pressure in the pressure vessel (56) stable; 5) Open the helium cylinder (3) to introduce helium into the hydrogen-helium gas supply branch and empty the air in the experimental system; 6) Close the helium cylinder (3), open the hydrogen cylinder (2), and pass hydrogen into the hydrogen-helium gas supply branch for a preset time, and check the second flowmeter (37) reading to prevent gas leakage; 7) Under the condition that hydrogen is not leaked, carry out a low-temperature experiment, the total temperature of the gas outlet is not more than 800K, and the second flowmeter (37) reading is checked; 8) Gradually increase the power of the electromagnetic induction heater (58), repeat step 6), and monitor the stability of the experimental system; 9) After the power of the electromagnetic induction heater (58) is increased to the specified power, and the total temperature of the gas outlet reaches the experimental requirement, continuously observe for a preset time, and after the parameters are stable, carry out the corrosion durability verification test of hydrogen on the test section (59); 10) After the test is completed, slowly reduce the power of the electromagnetic induction heater (58) to achieve slow cooling to avoid damaging the test section (59); 11) After the power of the electromagnetic induction heater (58) is reduced to 0, continuously pass hydrogen to remove the residual heat of the experimental system; 12) After the test section (59) is completely cooled, open the helium cylinder (3) to continuously pass helium to remove the test gas, repeat several times, close the pipeline valve, and keep the test pipeline sealed; 13) Start the vacuum pump (63) to maintain the normal pressure state of the pressure container (56); 14) Collect data, and after completion, close the power supply of the collection box; The steps of carrying out the corrosion durability verification test of air on the test section (59) are as follows: 1) Before starting the experiment, check whether the valves of the experimental system are open, whether the instruments and apparatus are in good condition, and whether the gas supply system has sufficient gas; 2) Start the vacuum pump (63) to evacuate the pressure container (56); 3) Pass nitrogen several times to fill the pressure container (56); 4) Adjust the pressure of the vacuum pump (63) and the first parallel nitrogen cylinder (1) to maintain the stable pressure in the pressure container (56); 5) Open the second parallel nitrogen cylinder (4) to pass nitrogen into the air-nitrogen gas supply branch to remove the air in the experimental system; 6) Close the second parallel nitrogen cylinder (4), open the air compressor (5), and pass air into the air-nitrogen gas supply branch for a preset time, and check the third flowmeter (38) reading to prevent gas leakage; 7) Open the gas preheater (54) to preheat the gas to 600K, and check the fourth flowmeter (39) reading; 8) Gradually increase the power of the electromagnetic induction heater (58), increase the power to the specified power, and after the total temperature of the gas outlet reaches the experimental requirement, continuously observe for a preset time, and after the parameters are stable, carry out the corrosion durability verification test of air on the test section (59); 9) After the test is completed, close the gas preheater (54), slowly reduce the power of the electromagnetic induction heater (58) to achieve slow cooling to avoid damaging the test section (59); 10) After the power of the electromagnetic induction heater (58) is reduced to 0, continuously pass air to remove the residual heat of the experimental system; 11) After the test section (59) is completely cooled, open the first parallel nitrogen cylinder (1) to continuously pass nitrogen to remove the test gas, repeat several times, close the pipeline valve, and keep the test pipeline sealed; 12) Start the vacuum pump (63) to maintain the normal pressure state of the pressure container (56); 13) Collect data, complete the power off the acquisition box; When the flow heat exchange test of the channel is carried out, the material of the test section (59) is replaced by a ceramic test piece, and the experimental process is the same as that of the corrosion durability verification test of the test section (59) by air.

2. The experimental method of the high-temperature gas flow heat exchange comprehensive experimental system according to claim 1, characterized in that: The tail gas treatment system is composed of three parts: the first tail gas treatment system composed of the rear pipeline of the gas cooling long tube (61), the fifth check valve (44), the fourth thermocouple (53), the pressure reducing valve (62) after the gas cooling long tube, the sixth pressure sensor (35), the first flame arrester (65) and the third foreign matter shielding device (70) arranged in sequence on the rear pipeline; the second tail gas treatment system composed of the rear pipeline of the vacuum pump (63) and the second flame arrester (66) and the second foreign matter shielding device (69); the third tail gas treatment system composed of the connecting pipeline of the first foreign matter shielding device (68) and the pressure vessel (56) and the safety valve (64) and the third flame arrester (67) arranged in sequence on the connecting pipeline; the cooled and decompressed gas flows through the first flame arrester (65), the second flame arrester (66), the third flame arrester (67), the third foreign matter shielding device (70), the second foreign matter shielding device (69) and the first foreign matter shielding device (68) and is discharged into the atmosphere.

3. The experimental method of the high-temperature gas flow heat exchange comprehensive experimental system according to claim 1, characterized in that: The test section (59) selects test pieces made of different materials according to different experimental purposes. When the corrosion durability verification test of the test section (59) by hydrogen is carried out, tungsten pipe is selected as the test piece material. When the corrosion durability verification test of the test section (59) by air is carried out, ODS steel is selected as the test piece material. When the flow heat exchange test of the channel is carried out, a ceramic test piece is selected.

4. The experimental method of the high-temperature gas flow heat exchange comprehensive experimental system according to claim 1, characterized in that: The loop pipe is made of standard 316L stainless steel pipe.

5. The experimental method of the high-temperature gas flow heat exchange comprehensive experimental system according to claim 1, characterized in that: The air and nitrogen in the air-nitrogen gas supply branch are heated to 600K by the gas preheater (54) for subsequent experiments.

6. The experimental method of the high-temperature gas flow heat exchange comprehensive experimental system according to claim 1, characterized in that: The electromagnetic induction heater (58) is arranged in zones and its heating power is controlled by an electrical control cabinet to simulate the uneven characteristics of the actual reactor power distribution. Material properties and failure tests, steady-state and transient tests of flow heat exchange are carried out under a variety of different working conditions. To protect the heating coil, the induction coil liquid cooling device (57) is used to cool the heating coil. To prevent heat loss, high-temperature insulation paint is applied to the heated test piece. For test sections made of non-metallic materials, a heating auxiliary part is added outside the test section, and a thin layer of tungsten metal is added outside the test section.

7. The experimental method of the high-temperature gas flow heat exchange comprehensive experimental system according to claim 1, characterized in that: The gas cooling long tube (61) is used to cool the heated experimental gas, realizing the convection heat dissipation of high-temperature gas-gas cooling long tube (61)-room temperature air.

8. The experimental method of the high-temperature gas flow heat exchange comprehensive experimental system according to claim 1, characterized in that: The induction element of the electromagnetic induction heater (58) is a spiral tube.

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