Lead bismuth and supercritical carbon dioxide heat exchanger loss of coolant accident experimental system and method

Abstract

The application discloses a kind of lead bismuth and supercritical carbon dioxide heat exchanger break accident experimental system and method, the system includes lead storage tank, argon buffer tank, experimental container, high temperature and high pressure carbon dioxide storage tank, carbon dioxide storage tank and buffer tank and other auxiliary systems, specifically to simulate lead bismuth and supercritical carbon dioxide heat exchanger break accident under the temperature, pressure and bubble evolution, lead bismuth reactor loop extreme thermal hydraulic phenomenon caused;The whole experimental system is operated by different pipeline valve control loop, the pressure required by experiment is flexibly controlled using gas booster pump, different heating temperatures are obtained by adjusting heating wire power, different sizes and thicknesses of copper film are flexibly replaced to simulate heat exchanger break condition, temperature change and pressure response during supercritical carbon dioxide is discharged into lead bismuth in experimental container are monitored, and lead bismuth and supercritical carbon dioxide heat exchanger experimental data under initial different temperature and pressure are obtained.

Description

Technical Field

[0001] This invention belongs to the field of nuclear energy development and new energy technology, specifically relating to an experimental system and method for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident. Background Technology

[0002] Small modular reactors (SMRs) using lead-bismuth as a coolant represent a cutting-edge field in international nuclear energy development. SMR systems employing a coupled heat exchange system of lead-bismuth and supercritical carbon dioxide are compact, highly efficient, and suitable for construction in inland areas and on islands. They also hold significant application potential in aerospace, deep-sea exploration, and other military-civilian integration fields. The secondary loop uses a heat exchanger to introduce supercritical carbon dioxide into the main vessel for heat exchange with the high-temperature liquid metal. This results in a large pressure and temperature difference across the heat transfer tubes, easily generating significant mechanical and thermal stresses. Combined with the vibration of the primary and secondary loop fluids and the corrosive effects of lead-bismuth, there is a risk of heat exchanger tube rupture, leading to supercritical carbon dioxide jets entering the lead-bismuth coolant in the reactor core, severely impacting the safety of the lead-bismuth reactor.

[0003] Most existing supercritical carbon dioxide (SCCO) release experiments involve releasing pressure into the atmosphere under low-temperature, high-pressure conditions, based on conventional applications of supercritical SCCO circulation systems and research on carbon capture, transport, and storage (CTS) systems. However, there is a lack of corresponding experimental and theoretical research on supercritical SCCO printed circuit board heat exchangers used in lead-bismuth reactors. When supercritical SCCO is released into lead-bismuth at high temperatures, the release phenomena will inevitably differ significantly from current understanding due to the much higher density and temperature of lead-bismuth compared to air. Furthermore, the unique physical properties of supercritical SCCO cannot be adequately explained by the interaction between water and lead alloys. Therefore, it is necessary to conduct supercritical SCCO release experiments under high-temperature conditions to study the phase change mechanism of supercritical SCCO under secondary loop depressurization and the interaction mechanism between supercritical SCCO and lead-bismuth, providing crucial experimental data for lead-bismuth reactor safety accident assessment and software development. Summary of the Invention

[0004] In order to overcome the problems existing in the prior art, the purpose of this invention is to provide an experimental system and method for lead-bismuth and supercritical carbon dioxide heat exchanger rupture accidents, so as to realize the mechanism of supercritical carbon dioxide injection of liquid lead-bismuth under heat exchanger rupture accidents and obtain key experimental data.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An experimental system for simulating a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident includes an experimental loop consisting of a lead storage tank system 100, an argon supply system 200, an experimental container system 300, a supercritical carbon dioxide system 400, and a carbon dioxide system 500. The lead storage tank system 100 stores and heats the lead-bismuth alloy and includes a lead storage tank 101, a first pressure gauge 102, a lead-bismuth level gauge 103, and a first thermocouple 104 mounted on the lead storage tank 101, a lead-bismuth solenoid valve 105, and a filter 106 connected to the lead storage tank 101. The argon supply system 200 provides argon protection and pressurization to the experimental loop and includes an argon buffer tank 201, a first argon supply valve 202, and a second argon supply valve 203. The experimental container system 300 simulates the working environment of the lead-bismuth alloy within a lead-bismuth pile and its interaction with supercritical carbon dioxide. The experimental container 301 includes a safety valve 302 installed on it and a measuring device 303 installed inside it. A supercritical carbon dioxide system 400 is used to heat and pressurize carbon dioxide to a supercritical state and release it into the experimental container. It includes a high-temperature, high-pressure supercritical carbon dioxide storage tank 406, a quick-opening valve 404, a vortex flow meter 403, a vertical check valve 402, a horizontal check valve 401, and a discharge section 408 connected sequentially to the tank. A second thermocouple 405 and a second pressure gauge 407 are also installed on the tank. A carbon dioxide system 500 is used to provide initial carbon dioxide gas to the supercritical carbon dioxide system 400. It includes a low-pressure carbon dioxide cylinder 501, a first gas valve 502, a gas booster pump 503, a carbon dioxide buffer tank 504, and a second gas valve 505. The lead storage tank 101 is connected to the bottom of the experimental container 301 through a lead-bismuth solenoid valve 105 and a filter 106, and is used to inject preheated lead-bismuth alloy into the experimental container 301. The argon buffer tank 201 is connected to the top of the lead storage tank 101 and the top of the experimental container 301 through the first argon supply valve 202 and the second argon supply valve 203, respectively. It is used to replace and pressurize the lead storage tank 101 and the experimental container 301 with inert gas before the experiment, and to purge and discharge the residual gas in the experimental container 301 after the experiment. The downstream of the high-temperature and high-pressure supercritical carbon dioxide storage tank 406 is connected to the bottom of the experimental container 301 through a horizontal check valve 401, a vertical check valve 402, a vortex flow meter 403, a quick-opening valve 404, and a discharge section 408. This is used to quickly inject supercritical carbon dioxide at a preset pressure and temperature into the experimental container 301 during the experiment to interact with the lead-bismuth alloy. The upstream of the tank is connected to the carbon dioxide system 500 through a second gas valve 505. The low-pressure carbon dioxide cylinder 501 is connected to the high-temperature and high-pressure supercritical carbon dioxide storage tank 406 through the first gas valve 502, the gas booster pump 503, the carbon dioxide buffer tank 504, and the second gas valve 505, and is used to provide carbon dioxide working fluid at a preset pressure to the supercritical carbon dioxide system 400.

[0006] The lead storage tank system 100, argon supply system 200, experimental container system 300, supercritical carbon dioxide system 400, and carbon dioxide system 500 are connected to the data acquisition system and power distribution system for real-time monitoring and recording of key parameters during the experiment. The data acquisition system uses high-frequency data acquisition equipment, one end of which is connected to the measuring device 303, the second thermocouple 405, the first thermocouple 104, the first pressure gauge 102, the second pressure gauge 407, and the vortex flow meter 403 arranged inside the experimental container 301, and the other end is connected to the control console. It is used to collect and record the temperature, pressure changes, and carbon dioxide mass flow rate data of the entire experimental system in real time during the supercritical carbon dioxide release process.

[0007] The measuring device 303 includes four measuring frames, each of which is an identical equilateral triangle, with several thermocouples evenly arranged, and high-frequency dynamic pressure sensors arranged at different heights.

[0008] The measuring device 303 has at least one measuring frame located within the gas space to measure the temperature change caused by gas compression and liquid coverage.

[0009] The discharge section 408 is located at the center of the bottom of the experimental container 301 and includes a screw cap 410, a copper film 411, and a connector 409. The screw cap 410 is internally threaded and connected to the connector 409. The copper film 411 is installed between the screw cap 410 and the connector 409 through a copper washer 412. The connector 409 is connected to the pipe by welding. Its structure is replaceable to achieve experimental conditions with different discharge nozzle diameters and different discharge length-to-diameter ratios.

[0010] The supercritical carbon dioxide system 400 includes a horizontal check valve 401 and a vertical check valve 402 to prevent lead and bismuth backflow after the experiment and to protect the vortex flow meter 403, the quick-opening valve 404, and the supercritical carbon dioxide system 400.

[0011] The quick-opening valve 404 is controlled by a relay to precisely control the opening and closing times of the experiment.

[0012] The high-temperature and high-pressure supercritical carbon dioxide storage tank 406 heats the carbon dioxide entering the experimental container through an electric heating wire, and alternately controls the heating and pressurization sequence to ensure the safe conduct of the experiment.

[0013] The experimental container 301 is made of 316 stainless steel, is formed by one-piece forging, and has a design pressure of 20MPa and a design temperature of 500℃.

[0014] The experimental method for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident experimental system involves the following steps: Before the experiment, the lead-bismuth alloy is heated to a predetermined experimental temperature via a lead storage tank 101, and the filter 106 and lead-bismuth solenoid valve 105 are opened to inject it into the experimental container 301; the experimental container 301 is purged with inert gas via an argon supply system 200 and a second argon supply valve 203; carbon dioxide is compressed and heated to a supercritical state via a carbon dioxide system 500 and a supercritical carbon dioxide system 400, and stored in a high-temperature, high-pressure supercritical carbon dioxide storage tank 406, with the pressure and temperature alternately adjusted to a predetermined level; during the experiment, a quick-opening valve 40 is opened via a relay. 4. Supercritical carbon dioxide is rapidly injected from the injection section 408 into the lead-bismuth alloy inside the experimental container 301. Simultaneously, the temperature, pressure, and mass flow rate data collected in real time by the measuring device 303, the second thermocouple 405, the second pressure gauge 407, and the vortex flow meter 403 inside the experimental container 301 are recorded by the data acquisition system. After the experiment is completed, the quick-opening valve 404 is closed and the safety valve 302 is opened to depressurize the experimental container 301. The residual carbon dioxide gas in the experimental container 301 and pipeline is purged by the argon gas supply system 200. The second argon gas supply valve 203 is opened to discharge the lead-bismuth alloy in the experimental container 301 back to the lead storage tank 101, and preparation is made for the next set of experiments.

[0015] Compared with the prior art, the present invention has the following advantages: 1. This experimental system integrates liquid lead-bismuth and supercritical carbon dioxide reaction systems, and can carry out high-temperature and high-pressure experiments, including the working conditions of lead-bismuth reactor-supercritical carbon dioxide system. It comprehensively explores the accident phenomena and consequences of the reaction between lead-bismuth and supercritical carbon dioxide under heat exchanger rupture accidents, and provides key experimental data for the development of related severe accident procedures.

[0016] 2. A high-frequency dynamic pressure sensor is used to dynamically acquire the pressure transmission signal inside the experimental container during the test, so as to capture the key pressure peaks and help to strengthen the assessment of the consequences of the accident.

[0017] 3. The measuring device adopts an equilateral triangle connection and arrangement, which ensures mechanical strength and stability during the test. The thermocouples are evenly arranged and their positions can be flexibly specified according to needs, allowing for comprehensive and detailed recording of experimental data.

[0018] 4. A carbon dioxide buffer tank is used to supply gas to the high-temperature and high-pressure carbon dioxide experimental container, and a strategy of alternating pressure and temperature control is adopted to avoid the huge energy release caused by the possible phase change of carbon dioxide during the experiment, thereby ensuring the safety of the experiment.

[0019] 5. The discharge section adopts a combination of replaceable screw caps and copper film, which are connected to the connector through internal threads, greatly improving corrosion resistance and replacement flexibility. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of an experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident provided in a specific embodiment of the present invention. Figure 2 This is a schematic diagram of the experimental container structure; Figure 3 This is a schematic diagram of the measuring device; Figure 4 This is a top view of the measuring device inside the experimental container; Figure 5 This is a schematic diagram of the spray section. Detailed Implementation

[0021] This invention provides an experimental system and method for simulating a breakage accident in a lead-bismuth and supercritical carbon dioxide heat exchanger. Specifically, it simulates the temperature, pressure, and bubble evolution under a breakage accident in a lead-bismuth and supercritical carbon dioxide heat exchanger, leading to extreme thermal-hydraulic phenomena in the primary loop of a lead-bismuth reactor. The invention is described in detail below with reference to the accompanying drawings and embodiments.

[0022] like Figure 1As shown, an experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident includes an experimental loop consisting of a lead storage tank system 100, an argon supply system 200, an experimental container system 300, a supercritical carbon dioxide system 400, and a carbon dioxide system 500. The lead storage tank system 100 is used to store and heat the lead-bismuth alloy, and includes the following devices: a lead storage tank 101, a first pressure gauge 102, a lead-bismuth level gauge 103, a first thermocouple 104, a lead-bismuth solenoid valve 105, and a filter 106. The argon supply system 200 is used to provide argon protection and pressurization to the experimental loop, and includes the following devices: an argon buffer tank 201, a first argon supply valve 202, and a second argon supply valve 203. The experimental container system 300 is used to simulate the working environment of the lead-bismuth alloy within the lead-bismuth pile. The system interacts with supercritical carbon dioxide and includes: an experimental container 301, a safety valve 302, and a measuring device 303; the supercritical carbon dioxide system 400 is used to heat and pressurize carbon dioxide to a supercritical state and release it into the experimental container, and includes: a horizontal check valve 401, a vertical check valve 402, a vortex flow meter 403, a quick-opening valve 404, a second thermocouple 405, a high-temperature and high-pressure supercritical carbon dioxide storage tank 406, a second pressure gauge 407, and a discharge section 408; the carbon dioxide system 500 is used to provide initial carbon dioxide gas to the supercritical carbon dioxide system 400, and includes: a low-pressure carbon dioxide cylinder 501, a first gas valve 502, a gas booster pump 503, a carbon dioxide buffer tank 504, and a second gas valve 505. The lead storage tank 101 is connected to the bottom of the experimental container 301 through a lead-bismuth solenoid valve 105 and a filter 106, and is used to inject preheated lead-bismuth alloy into the experimental container 301. The argon buffer tank 201 is connected to the top of the lead storage tank 101 and the top of the experimental container 301 through the first argon supply valve 202 and the second argon supply valve 203, respectively. It is used to replace and pressurize the lead storage tank 101 and the experimental container 301 with inert gas before the experiment, and to purge and discharge the residual gas in the experimental container 301 after the experiment. The downstream of the high-temperature and high-pressure supercritical carbon dioxide storage tank 406 is connected to the bottom of the experimental container 301 through a horizontal check valve 401, a vertical check valve 402, a vortex flow meter 403, a quick-opening valve 404, and a discharge section 408. This is used to quickly inject supercritical carbon dioxide at a preset pressure and temperature into the experimental container 301 during the experiment to interact with the lead-bismuth alloy. The upstream of the tank is connected to the carbon dioxide system 500 through a second gas valve 505. The low-pressure carbon dioxide cylinder 501 is connected to the high-temperature and high-pressure supercritical carbon dioxide storage tank 406 through the first gas valve 502, the gas booster pump 503, the carbon dioxide buffer tank 504, and the second gas valve 505, and is used to provide carbon dioxide working fluid at a certain pressure to the supercritical carbon dioxide system 400.

[0023] The lead storage tank system 100, argon supply system 200, experimental container system 300, supercritical carbon dioxide system 400, and carbon dioxide system 500 are connected to the data acquisition system and power distribution system for real-time monitoring and recording of key parameters during the experiment. The data acquisition system uses high-frequency data acquisition equipment, one end of which is connected to the measuring device 303, the second thermocouple 405, the first thermocouple 104, the first pressure gauge 102, the second pressure gauge 407, and the vortex flow meter 403 arranged inside the experimental container 301, and the other end is connected to the control console. It is used to collect and record the temperature, pressure changes, and carbon dioxide mass flow rate data of the entire experimental system in real time during the supercritical carbon dioxide release process.

[0024] like Figure 2 As shown, the experimental container 301 mainly withstands the impact of high-temperature lead-bismuth and high-temperature, high-pressure supercritical carbon dioxide. A safety valve 302 is arranged at the top to control the pressure release during and after the experiment. Part of the internal space of the container is filled with liquid lead-bismuth, and the remaining upper space is filled with argon gas as a covering gas. A third pressure gauge 304 and a fourth pressure gauge 305 are installed to measure the static pressure of the lead-bismuth space and the upper gas space, respectively. The measuring device 303 is welded to the top of the experimental container 401 through three steel frames. The third pressure gauge 304 and the fourth pressure gauge 305 are high-frequency dynamic pressure sensors.

[0025] like Figure 3 As shown, the measuring device 303 includes four measuring frames, each of which is an identical equilateral triangle. Several thermocouples are evenly arranged to measure the transient temperature changes during the spraying process, and high-frequency dynamic pressure sensors are arranged at different heights to measure the pressure wave transmission inside the experimental container 301.

[0026] like Figure 4 The diagram shown is a top view of the measuring device 303, and a schematic diagram of the discharge section 408 is shown below. Figure 5 As shown, located at the center of the bottom of the experimental container 301, it includes a screw cap 410, a copper film 411, and a connector 409. The screw cap 410 is internally threaded and connected to the connector 409. The copper film 411 is installed between the screw cap 410 and the connector 409 through a copper washer 412. The connector 409 is connected to the pipe by welding. Its structure is replaceable to achieve experimental conditions with different nozzle diameters and different length-to-diameter ratios.

[0027] The supercritical carbon dioxide system 400 includes a horizontal check valve 401 and a vertical check valve 402 to prevent lead and bismuth backflow after the experiment and to protect the vortex flow meter 403, the quick-opening valve 404, and the supercritical carbon dioxide system 400.

[0028] The quick-opening valve 404 is controlled by a relay to precisely control the opening and closing times of the experiment.

[0029] The high-temperature and high-pressure supercritical carbon dioxide storage tank 406 heats the carbon dioxide entering the experimental container through an electric heating wire, and alternately controls the heating and pressurization sequence to ensure the safe conduct of the experiment.

[0030] The experimental method for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident experimental system comprises the following steps: Before the experiment, the lead-bismuth alloy is heated to the predetermined experimental temperature through the lead storage tank 101, and the filter 106 and lead-bismuth solenoid valve 105 are opened to inject it into the experimental container 301; the experimental container 301 is purged with inert gas by opening the second argon supply valve 203 through the argon supply system 200; carbon dioxide is compressed and heated to a supercritical state through the carbon dioxide system 500 and the supercritical carbon dioxide system 400, and stored in the high-temperature and high-pressure supercritical carbon dioxide storage tank 406, with the pressure and temperature alternately adjusted to the predetermined levels; during the experiment, the fast-acting relay is opened... Valve 404 is opened to allow supercritical carbon dioxide to be rapidly injected from the injection section 408 into the lead-bismuth alloy inside the experimental container 301. Simultaneously, the temperature, pressure, and mass flow rate data collected in real time by the measuring device 303, the second thermocouple 405, the second pressure gauge 407, and the vortex flow meter 403 inside the experimental container 301 are recorded by the data acquisition system. After the experiment is completed, the quick-opening valve 404 is closed, and the safety valve 302 is opened to depressurize the experimental container 301. The residual carbon dioxide gas in the experimental container 301 and pipelines is purged by the argon gas supply system 200. The second argon gas supply valve 203 is opened to discharge the lead-bismuth alloy in the experimental container 301 back to the lead storage tank 101, and preparation is made for the next set of experiments. The entire experimental system operates through different pipeline valve control loops, uses a gas booster pump to flexibly control the pressure required for the experiment, obtains different heating temperatures by adjusting the power of the heating wire, flexibly replaces copper films of different sizes and thicknesses to simulate the rupture of the heat exchanger, monitors the temperature changes and pressure responses during the injection of supercritical carbon dioxide into the lead-bismuth process in the experimental container, and obtains experimental data of lead-bismuth and supercritical carbon dioxide heat exchangers under different initial temperatures and pressures.

[0031] In a preferred embodiment of the present invention, a high-frequency dynamic pressure sensor is selected as the pressure sensor, and the sampling frequency is not less than 20kHz.

[0032] As a preferred embodiment of the present invention, the experimental container 301 is made of 316 stainless steel, is formed by one-piece forging, and has a design pressure of 20MPa and a design temperature of 500℃.

[0033] In a preferred embodiment of the present invention, the measuring device 303 has at least one measuring frame located in the gas space to measure the temperature change caused by gas compression and liquid coverage.

[0034] The above description is a further detailed explanation of the present invention in conjunction with specific preferred embodiments. It should not be considered that the specific embodiments of the present invention are limited to this. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention, and all such deductions or substitutions should be considered to fall within the scope of patent protection determined by the submitted claims.

Claims

1. An experimental system for simulating a breakage accident in a lead-bismuth and supercritical carbon dioxide heat exchanger, characterized in that: An experimental circuit comprising a lead storage tank system (100), an argon supply system (200), an experimental container system (300), a supercritical carbon dioxide system (400), and a carbon dioxide system (500); wherein, the lead storage tank system (100) is used to store and heat lead-bismuth alloy, and includes the following devices: a lead storage tank (101), a first pressure gauge (102), a lead-bismuth level gauge (103), and a first thermocouple (104) installed on the lead storage tank (101), and connected to the lead storage tank (101). 1) Connected lead-bismuth solenoid valve (105) and filter (106); Argon supply system (200) for providing argon protection and pressurization to the experimental circuit, including: argon buffer tank (201), first argon supply valve (202) and second argon supply valve (203); Experimental container system (300) for simulating the working environment of lead-bismuth alloy in a lead-bismuth pile and interacting with supercritical carbon dioxide, including: experimental container (301), set in the experimental container ( The safety valve (302) on the experimental container (301) and the measuring device (303) installed inside the experimental container (301) are included. The supercritical carbon dioxide system (400) is used to heat and pressurize carbon dioxide to a supercritical state and spray it into the experimental container. The device includes: a high temperature and high pressure supercritical carbon dioxide storage tank (406), a quick-opening valve (404), a vortex flow meter (403), a vertical check valve (402), a horizontal check valve (401) and a spray section (408) connected in sequence to the high temperature and high pressure supercritical carbon dioxide storage tank (406), a second thermocouple (405) and a second pressure gauge (407) installed on the high temperature and high pressure supercritical carbon dioxide storage tank (406). The carbon dioxide system (500) is used to provide initial carbon dioxide gas to the supercritical carbon dioxide system (400). The device includes: a low pressure carbon dioxide cylinder (501), a first gas valve (502), a gas booster pump (503), a carbon dioxide buffer tank (504) and a second gas valve (505). The lead storage tank (101) is connected to the bottom of the experimental container (301) through a lead-bismuth solenoid valve (105) and a filter (106) for injecting preheated lead-bismuth alloy into the experimental container (301); The argon buffer tank (201) is connected to the top of the lead storage tank (101) and the top of the experimental container (301) through the first argon supply valve (202) and the second argon supply valve (203), respectively. It is used to replace and pressurize the lead storage tank (101) and the experimental container (301) with inert gas before the experiment, and to purge and discharge the residual gas in the experimental container (301) after the experiment. The high-temperature and high-pressure supercritical carbon dioxide storage tank (406) is connected to the bottom of the experimental container (301) downstream through a horizontal check valve (401), a vertical check valve (402), a vortex flow meter (403), a quick-opening valve (404), and a discharge section (408), which is used to quickly inject supercritical carbon dioxide at a preset pressure and temperature into the experimental container (301) during the experiment to interact with the lead-bismuth alloy. Upstream, it is connected to the carbon dioxide system (500) through a second gas valve (505). The low-pressure carbon dioxide cylinder (501) is connected to the high-temperature and high-pressure supercritical carbon dioxide storage tank (406) through the first gas valve (502), the gas booster pump (503), the carbon dioxide buffer tank (504), and the second gas valve (505), and is used to provide carbon dioxide working fluid at a preset pressure to the supercritical carbon dioxide system (400).

2. The experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident according to claim 1, characterized in that: The lead storage tank system (100), argon supply system (200), experimental container system (300), supercritical carbon dioxide system (400), and carbon dioxide system (500) are connected to the data acquisition system and power distribution system for real-time monitoring and recording of key parameters during the experiment. The data acquisition system uses high-frequency data acquisition equipment. One end of the equipment is connected to the measuring device (303) arranged inside the experimental container (301), as well as the second thermocouple (405), the first thermocouple (104), the first pressure gauge (102), the second pressure gauge (407), and the vortex flow meter (403). The other end is connected to the control console. The system is used to collect and record the temperature, pressure changes, and mass flow rate data of the entire experimental system in real time during the supercritical carbon dioxide release process.

3. The experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident according to claim 1, characterized in that: The measuring device (303) includes four measuring frames, each of which is an identical equilateral triangle, with several thermocouples evenly arranged, and high-frequency dynamic pressure sensors arranged at different heights.

4. The experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident according to claim 1, characterized in that: The measuring device (303) has at least one measuring frame located in the gas space to measure the temperature change caused by gas compression and liquid coverage.

5. The experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident according to claim 1, characterized in that: The discharge section (408) is located at the center of the bottom of the experimental container (301), and includes a screw cap (410), a copper film (411), and a connector (409). The screw cap (410) is internally threaded and connected to the connector (409). The copper film (411) is installed between the screw cap (410) and the connector (409) through a copper washer (412). The connector (409) is connected to the pipe by welding. Its structure is replaceable to achieve experimental conditions with different discharge nozzle diameters and different discharge length-to-diameter ratios.

6. The experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident according to claim 1, characterized in that: The supercritical carbon dioxide system (400) includes a horizontal check valve (401) and a vertical check valve (402) to prevent lead and bismuth backflow after the experiment and to protect the vortex flow meter (403), the quick-opening valve (404), and the supercritical carbon dioxide system (400).

7. The experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident according to claim 1, characterized in that: The quick-opening valve (404) is controlled by a relay to precisely control the opening and closing times of the experiment.

8. The experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident according to claim 1, characterized in that: The high-temperature and high-pressure supercritical carbon dioxide storage tank (406) heats the carbon dioxide entering the experimental container through an electric heating wire, and alternately controls the heating and pressurization sequence to ensure the safe conduct of the experiment.

9. The experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident according to claim 1, characterized in that: The experimental container (301) is made of 316 stainless steel and is formed by one-piece forging. The design pressure is 20MPa and the design temperature is 500℃.

10. The experimental method for an experimental system for a lead-bismuth and supercritical carbon dioxide heat exchanger rupture accident as described in any one of claims 1 to 9, characterized in that: Before the experiment, the lead-bismuth alloy was heated to the predetermined experimental temperature through the lead storage tank (101), and the filter (106) and lead-bismuth solenoid valve (105) were opened to inject it into the experimental container (301); the experimental container (301) was purged with inert gas by opening the second argon supply valve (203) through the argon supply system (200); carbon dioxide was compressed and heated to the supercritical state through the carbon dioxide system (500) and the supercritical carbon dioxide system (400), and stored in the high-temperature and high-pressure supercritical carbon dioxide storage tank (406), and the pressure and temperature were alternately adjusted to the predetermined pressure; during the experiment, the quick-opening valve (404) was opened through the relay to allow the supercritical carbon dioxide to be quickly released from the spray section (408). The lead-bismuth alloy is rapidly injected into the experimental container (301), and the temperature, pressure and mass flow data collected in the experimental container (301) by the measuring device (303), the second thermocouple (405), the second pressure gauge (407) and the vortex flow meter (403) are recorded in real time through the data acquisition system. After the experiment is completed, the quick-opening valve (404) is closed and the safety valve (302) is opened to depressurize the experimental container (301). The residual carbon dioxide gas in the experimental container (301) and pipeline is purged by the argon gas supply system (200). The second argon gas supply valve (203) is opened to discharge the lead-bismuth alloy in the experimental container (301) back to the lead storage tank (101) and prepare for the next set of experiments.

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