Liquid lead bismuth flow heat exchange experimental device with static mass calibration device

Abstract

The application discloses a liquid lead bismuth flow heat exchange experimental device with a static mass calibration device, which comprises a lead bismuth thermal hydraulic experiment main loop, an electromagnetic flowmeter static mass calibration device, an electric heating system, a heat conducting oil system, a gas system and a data acquisition system. The lead bismuth thermal hydraulic experiment main loop comprises a lead storage tank, a heating experiment section, a tube shell heat exchanger, a pressure stabilizing tank, an electromagnetic pump and an electromagnetic flowmeter. The static mass calibration device comprises an electromagnetic flowmeter, a commutator, a lead bismuth weighing tank and a weighing device. The electric heating system comprises electric heating wires, electric heating rods and a variable power voltage regulator, and is used for lead bismuth heating and loop preheating. The heat conducting oil cooling system comprises a tube shell heat exchanger, an oil-water heat exchanger, a heat conducting oil tank and a heat conducting oil pump, and is used for maintaining the heat balance of the loop. The gas system comprises an inert gas buffer tank and a vacuum pump, and is used for gas replacement. The data acquisition system comprises a data acquisition card, temperature sensors, pressure difference sensors and an electromagnetic flowmeter, and is used for recording experimental data.

Description

Technical Field

[0001] This invention belongs to the field of experimental research technology of liquid metal in advanced nuclear reactors, and specifically relates to an experimental device for liquid lead-bismuth flow heat exchange with a static mass calibration device. Background Technology

[0002] Lead-bismuth fast reactors, as a reference reactor type for fourth-generation nuclear energy systems, have advantages over thermal neutron reactors in terms of higher power density and greater safety and reliability. The thermo-hydraulic characteristics of lead-bismuth coolant are the foundation for the thermal design and safety analysis of lead-bismuth reactors, and extensive experimental and theoretical research has been conducted internationally on the thermal performance of lead-bismuth coolant.

[0003] Liquid lead-bismuth flow rate measurement is a key issue in the experimental research of the thermal performance of lead-bismuth coolants. In the thermal experimental research of lead-bismuth coolants, accurate measurement of the liquid lead-bismuth flow rate requires high-precision calibration of highly stable flow meters. Existing lead-bismuth thermal-hydraulic experimental benches generally use the dynamic volumetric method to calibrate electromagnetic flow meters. This involves calculating the loop lead-bismuth volumetric flow rate based on the change in the lead-bismuth volume in the calibration cylinder within a calibration time interval. However, because the density of lead-bismuth alloys is significantly affected by temperature, and the lead-bismuth flow rate fluctuates considerably as the liquid level in the calibration cylinder decreases, the accuracy of electromagnetic flow meters calibrated using this method is relatively low. Therefore, improvements to the loop calibration method are needed. Summary of the Invention

[0004] To improve the calibration method of liquid lead-bismuth flow heat transfer experimental apparatus, this invention provides a liquid lead-bismuth flow heat transfer experimental apparatus with a static mass calibration device. Using the static mass method, the net mass of the collected liquid is calculated based on the tare weight and gross weight obtained before and after the liquid lead-bismuth enters the weighing container through the commutator within a calibration time interval. This yields the loop mass flow rate, which is then used to calibrate the electromagnetic flowmeter. Compared to the existing dynamic volumetric method, this method offers higher accuracy, helps obtain more precise liquid lead-bismuth flow parameters, facilitates the study of practical engineering problems related to liquid lead-bismuth, and guides the operation and design of liquid lead-bismuth reactors.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A liquid lead-bismuth flow heat transfer experimental device with a static mass calibration device includes a lead-bismuth thermal-hydraulic experimental main circuit, an electromagnetic flowmeter static mass calibration device, an electric heating system, a heat transfer oil cooling system, a gas system, and a data acquisition system.

[0007] The main loop of the lead-bismuth thermal-hydraulic experiment consists of a lead storage tank 101, a heating test section 102, a shell-and-tube heat exchanger 103, a pressure stabilizing tank 104, an electromagnetic pump 105, and an electromagnetic flowmeter 106. Each piece of equipment is connected sequentially via a main pipeline, and the components of the main loop are arranged in layers. The lead storage tank 101 is used to heat and melt the lead-bismuth alloy; the heating test section 102 is used to simulate the fuel rods in the core of a lead-bismuth fast reactor; the pressure stabilizing tank 104 is used to maintain stable pressure in the main loop during electromagnetic flowmeter calibration. When the main loop starts, high-temperature liquid lead-bismuth flows sequentially through the heating test section 102, the shell-and-tube heat exchanger 103, the pressure stabilizing tank 104, the electromagnetic pump 105, the electromagnetic flowmeter 106, and the commutator 201 for circulation. After the experiment, the lead-bismuth flows back into the lead storage tank 101.

[0008] The electromagnetic flowmeter static mass calibration device consists of a commutator 201, a lead-bismuth weighing tank 202, and a weighing device 203. The commutator 201 is used to adjust the flow of lead-bismuth to the main circuit or the lead-bismuth weighing tank 202. The lead-bismuth weighing tank 202 is used to load high-temperature liquid lead-bismuth, and the weighing device 203 is used to weigh the total mass flowing into the lead-bismuth weighing tank 202 within a specified calibration time.

[0009] The electric heating system includes an electric heating rod, an electric heating wire, and a variable power regulator; the pipes and valves in the experimental device are wound with electric heating wire and controlled by the variable power regulator for preheating the circuit and lead-bismuth; the electric heating rod is installed in the heating test section 102 and its power is controlled by the variable power regulator to adjust the outlet temperature of the heating test section.

[0010] The heat transfer oil cooling system consists of a shell-and-tube heat exchanger 103, an oil-water heat exchanger 301, a heat transfer oil tank 302, and a heat transfer oil pump 303. The heat transfer oil is pumped from the heat transfer oil tank 302 into the secondary side of the shell-and-tube heat exchanger 103 by the heat transfer oil pump 303. After being heated by the high-temperature liquid lead-bismuth on the primary side, it flows through the oil-water heat exchanger 301 and is cooled by the cooling water on the secondary side. It then returns to the heat transfer oil tank 302, completing the circulation of high-temperature heat transfer oil in the heat transfer oil cooling system.

[0011] The gas system consists of an inert gas buffer tank 401 and a vacuum pump 402, which is used to extract a vacuum state in the loop and pressurize high-temperature liquid lead-bismuth from the lead storage tank 101 into the main loop by means of inert gas replacement.

[0012] The data acquisition system consists of a data acquisition card and temperature sensors, differential pressure sensors, and electromagnetic flowmeters 106 arranged in the main circuit. The data acquisition card transmits the measurement point parameters through the acquisition line, and the computer monitors and records the temperature, pressure, differential pressure, and flow parameters. The temperature sensor is located at the electric heating rod 506, the pressure sensor is arranged at both ends of the electric heating rod 506, and the electromagnetic flowmeter 106 is arranged between the electromagnetic pump 105 and the commutator 201, and is connected to the upstream and downstream equipment through pipelines.

[0013] The heating test section 102 is a 7-bar bundle test section, including test section 501. Test section 501 is connected to the upper chamber 502 and the lower chamber 503. The 7 electric heating rods 506 inside the hexagonal sleeve of test section 501 are fixed by the positioning grid 504.

[0014] Before the circuit is started, the lead storage tank 101 melts the lead and bismuth into a liquid state through an electric heating rod, and then drives it into the main circuit of the lead and bismuth thermal-hydraulic experiment through the pressure difference of inert gas.

[0015] The experimental setup uses an electromagnetic pump 105 to provide the driving head, which powers the main loop of liquid lead-bismuth flow. An electromagnetic flowmeter 106 measures the output flow signal. The electromagnetic pump 105 adjusts its output power through a PI controller 701, thereby changing the flow rate of the liquid lead-bismuth in the main loop. The flow signal output by the electromagnetic flowmeter 106 enters the PI controller 701, which controls the frequency of the electromagnetic pump 105 by judging the increase or decrease of the flow rate: when the flow rate increases, the frequency of the electromagnetic pump 105 is decreased, thus decreasing the flow rate; when the flow rate decreases, the frequency of the electromagnetic pump 105 is increased, thus increasing the flow rate, thereby maintaining a stable loop flow rate.

[0016] The electromagnetic flowmeter static mass calibration device uses a commutator 201 driven by a cylinder to change the position of the baffle. Before the calibration of the electromagnetic flowmeter 106 begins, the lead and bismuth are guided to the main circuit. During calibration, the commutator is reversed to guide the lead and bismuth to the weighing tank 202. After the calibration is completed, the commutator is reversed again to guide the lead and bismuth to the main circuit.

[0017] The electromagnetic flowmeter static mass calibration device adopts the static mass method, that is, within the calibration time interval, the net mass of the collected liquid lead bismuth is calculated based on the weights obtained before and after the liquid lead bismuth enters the lead bismuth weighing tank 202 through the commutator 201, thereby obtaining the main circuit mass flow rate and calibrating the electromagnetic flowmeter 106. After the calibration is completed, the reading is recorded after the reading of the weighing device 203 stabilizes.

[0018] The steps for calibrating an electromagnetic flowmeter using the static mass method are as follows:

[0019] Step 1. The main circuit is started. The baffle of commutator 201 is located on the main circuit side. Liquid lead-bismuth flows through the heating test section 102, shell-and-tube heat exchanger 103, buffer tank 104, electromagnetic pump 105, electromagnetic flowmeter 106, and commutator 201, and returns to the heating test section 102 for circulation.

[0020] Step 2. After the reading of the electromagnetic flowmeter 106 stabilizes, record the reading and start calibration. The baffle of the commutator 201 moves to the lead-bismuth weighing tank side and starts timing. Liquid lead-bismuth flows through the commutator 201 into the lead-bismuth weighing tank 202.

[0021] Step 3. When the specified calibration time is reached, the calibration ends, the baffle of commutator 201 moves to the main circuit side and the timing ends, and the liquid lead bismuth flows through commutator 201 into the main circuit pipeline for circulation.

[0022] Step 4. After the reading of the weighing device 203 stabilizes, record the reading. Calculate the mass flow rate from the specified calibration time and the net mass of the collected liquid lead and bismuth, and record it.

[0023] Step 5. Change the main circuit flow rate by changing the frequency of electromagnetic pump 105, repeat the above calibration process, and obtain the relationship curve between the reading of electromagnetic flowmeter 106 and the main circuit flow rate to complete the calibration of electromagnetic flowmeter 106.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] 1. Based on fulfilling the basic functions of the liquid lead-bismuth flow heat exchange experimental circuit, this invention adds a static mass calibration device for electromagnetic flowmeters. Compared with the existing dynamic volumetric flowmeter calibration device, the static mass flowmeter calibration device has the characteristics of small error and high reliability, and can achieve accurate calibration of the electromagnetic flowmeter in the circuit.

[0026] 2. This invention employs a PI controller-controlled electromagnetic pump: When the liquid level in the pressure tank decreases, the lead-bismuth flow rate through the electromagnetic flowmeter changes. The frequency of the electromagnetic pump is controlled by judging the increase or decrease in flow rate: when the flow rate increases, the electromagnetic pump frequency is decreased to reduce the flow rate; when the flow rate decreases, the electromagnetic pump frequency is increased to increase the flow rate. This maintains stable loop flow and improves calibration accuracy. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of an experimental apparatus for heat transfer of liquid lead-bismuth flow with a static mass calibration device.

[0028] Figure 2 This is a schematic diagram of a 7-bar bundle test section.

[0029] Figure 3 This is a schematic diagram of a commutator. Detailed Implementation

[0030] The present invention will now be further described with reference to examples and accompanying drawings:

[0031] like Figure 1As shown, the present invention provides an experimental apparatus for liquid lead-bismuth flow heat transfer with a static mass calibration device, comprising a lead-bismuth thermal-hydraulic experimental main circuit, an electromagnetic flowmeter static mass calibration device, an electric heating system, a heat transfer oil cooling system, a gas system, and a data acquisition system. The main loop of the lead-bismuth thermal-hydraulic experiment consists of a lead storage tank 101, a heating test section 102, a shell-and-tube heat exchanger 103, a pressure stabilizing tank 104, an electromagnetic pump 105, and an electromagnetic flowmeter 106. All equipment is connected sequentially via a main pipeline. The components of the main loop are arranged in layers using a steel frame structure. The lead storage tank 101 has a lead-bismuth storage capacity of 10t and contains 12 horizontally arranged heating rods for heating and melting the lead-bismuth alloy. The heating test section 102 is a 7-rod bundle test section used to simulate the fuel rods in a lead-bismuth fast reactor core. The heating test section 102 includes a test section 501, which is connected to the upper chamber 502 and the lower chamber 503 by welding. The 7 electric heating rods 506 inside the hexagonal sleeve of the test section 501 are fixed by 3 positioning grids 504. The pressure stabilizing tank 104 is used to maintain stable pressure in the main loop during electromagnetic flowmeter calibration. When the main circuit is started, the high-temperature liquid lead-bismuth passes through the heating test section 102, the shell-and-tube heat exchanger 103, the pressure stabilizing tank 104, the electromagnetic pump 105, and the electromagnetic flowmeter 106 in sequence. After the experiment, the lead-bismuth flows back into the lead storage tank 101.

[0032] The electromagnetic flowmeter static mass calibration device consists of a commutator 201, a lead-bismuth weighing tank 202, and a weighing device 203. The commutator 201 is used to adjust the flow direction of lead-bismuth. It is driven by a cylinder and guides the lead-bismuth to the main circuit before the calibration of the electromagnetic flowmeter 106 begins. During calibration, it reverses the direction to guide the lead-bismuth to the lead-bismuth weighing tank 202. After calibration, it reverses the direction again to guide the lead-bismuth to the main circuit. The lead-bismuth weighing tank 202 and the weighing device 203 are used to load and weigh the total mass flowing into the lead-bismuth weighing tank 202 within a specified calibration time.

[0033] The electric heating system includes an electric heating rod, an electric heating wire, and a variable power regulator. In the experimental setup, the pipes and valves are wound with the electric heating wire, and the variable power regulator controls the preheating of the circuit and lead-bismuth. The electric heating rod is installed in the heating test section 102, and its power is controlled by the variable power regulator to adjust the outlet temperature of the heating test section.

[0034] The heat transfer oil cooling system consists of a shell-and-tube heat exchanger 103, an oil-to-water heat exchanger 301, a heat transfer oil tank 302, and an air-cooled heat transfer oil pump 303. The heat transfer oil is pumped from the heat transfer oil tank 302 into the secondary side of the shell-and-tube heat exchanger 103 by the heat transfer oil pump 303. After being heated by the high-temperature liquid lead-bismuth on the primary side, the oil flows through the oil-to-water heat exchanger 301 and is cooled by the cooling water on the secondary side before returning to the heat transfer oil tank 302, completing the high-temperature heat transfer oil circulation within the heat transfer oil cooling system.

[0035] The gas system consists of an inert gas buffer tank 401 and a vacuum pump 402, used to extract a vacuum in the loop and pressurize high-temperature liquid lead-bismuth from the lead storage tank 101 into the main loop through inert gas replacement. In this embodiment, argon is used as the inert gas.

[0036] The data acquisition system consists of a data acquisition card and temperature sensors, differential pressure sensors, and electromagnetic flowmeters arranged in the main circuit. The data acquisition card transmits the measurement point parameters to the data acquisition point via acquisition lines, and the computer monitors and records the temperature, pressure, differential pressure, and flow parameters. The temperature sensor is located at the electric heating rod 506, the pressure sensor is located at both ends of the electric heating rod 506, and the electromagnetic flowmeter 106 is located between the electromagnetic pump 105 and the commutator 201, connected to upstream and downstream equipment via pipelines.

[0037] like Figure 2 The diagram shows a 7-bar bundle test section. In the 7-bar bundle test section, the test section 501 is connected to the upper chamber 502 and the lower chamber 503 by welding. The 7 electric heating rods 506 inside the hexagonal sleeve of the test section are fixed by 3 positioning grids 504.

[0038] In a preferred embodiment of the present invention, the 7 rod bundle test sections can be replaced with different numbers and types of rod bundles and other types of test sections as needed to meet the requirements of different test conditions.

[0039] like Figure 3 The diagram shows a commutator. The commutator is driven by a cylinder 603. Liquid lead-bismuth flows from the upstream pipe through nozzle 601 into the commutator, and is guided to different flow channels by a baffle 602. Before calibration begins, baffle 602 is located on the far right. Once the circuit flow rate stabilizes, calibration begins, and baffle 602 moves to the left under the action of cylinder 603, guiding the liquid lead-bismuth to the weighing tank. At the end of calibration, baffle 602 moves to the right under the action of cylinder 603, guiding the liquid lead-bismuth to the main circuit.

[0040] In a preferred embodiment of the present invention, the commutator can be replaced with a commutator of different drive types as needed. Depending on the test conditions and flow rate, the calibration time and timing method during the calibration process can be adjusted as required.

[0041] The steps for calibrating the electromagnetic flowmeter using the static mass method in this invention are as follows: 1. The main circuit is started, with the baffle of commutator 201 on the right. Liquid lead-bismuth flows through the heating test section 102, shell-and-tube heat exchanger 103, buffer tank 104, electromagnetic pump 105, electromagnetic flowmeter 106, and commutator 201, returning to the heating test section 102 for circulation. 2. When the reading of electromagnetic flowmeter 106 stabilizes, the reading is recorded and calibration begins. The baffle of commutator 201 moves to the left and timing begins. Liquid lead-bismuth flows through commutator 201 into lead-bismuth weighing tank 202. 3. When the specified calibration time is reached, calibration ends. The baffle of commutator 201 moves to the right and timing ends. Liquid lead-bismuth flows through commutator 201 into the main circuit pipeline for circulation. 4. After the reading of weighing device 203 stabilizes, the reading is recorded. The mass flow rate is calculated from the specified calibration time and the net mass of collected liquid lead-bismuth and recorded. 5. By changing the frequency of the electromagnetic pump 105 to change the flow rate in the main circuit, repeat the above calibration process to obtain the relationship curve between the reading of the electromagnetic flowmeter 106 and the flow rate in the main circuit, thus completing the calibration of the electromagnetic flowmeter 106.

[0042] like Figure 1 As shown, the experimental method of the device of the present invention is as follows:

[0043] Step 1: Before starting the experiment, first fill the main circuit of the lead-bismuth thermal-hydraulic experiment with high-purity inert gas through the gas system, maintaining the circuit pressure at 0.3MPa to 0.4MPa. If the circuit pressure does not decrease significantly within 2 hours, the circuit sealing performance is considered to meet the experimental requirements. Then, use the gas system to repeatedly fill and release the circuit with inert gas to replace the air, repeating this process 3 to 5 times.

[0044] Step 2: Turn on the electric heating system to heat the lead-bismuth alloy in the lead storage tank 101 at room temperature to 150°C to melt it. During this process, the power of the electric heating wire is controlled to be below 50% of the rated power by the variable power regulator, and the temperature rise rate is controlled to be 30°C / h. At the same time, the equipment through which the liquid lead-bismuth flows, such as the circuit pipes and valves, is preheated to 180°C.

[0045] Step 3: Injecting lead-bismuth into the main experimental circuit. First, set the input current of the electromagnetic pump 105 to zero. Open all lead-bismuth valves in the experimental circuit, the lead storage tank inlet valve, and the exhaust valve on the top of the buffer tank. Slowly inject inert gas into the lead storage tank 101 using the gas system, ensuring the injection process is as gradual as possible. Once all the corresponding liquid level indicator lights in the buffer tank 101 are illuminated, immediately close the lead-bismuth valve on the lead storage tank outlet pipeline, the lead storage tank inlet valve, and the exhaust valve on the top of the buffer tank. During the operation of the experimental circuit, the lead storage tank needs to be kept warm, and the heating wire power should be reduced to 20% of its rated power.

[0046] Step 4: Change the input current of the electromagnetic pump 105 until the loop flow stabilizes, i.e., the reading of the electromagnetic flowmeter 106 remains stable. Then, begin calibrating the electromagnetic flowmeter 106. Obtain the relationship curve between the electromagnetic flowmeter reading and the main loop flow using the static mass calibration method, thus completing the electromagnetic flowmeter calibration.

[0047] Step 5: After the electromagnetic flowmeter 106 is calibrated, the experiment begins. For different operating conditions, the inlet flow rate of the heating test section is changed by altering the input current of the electromagnetic pump 105, and the inlet temperature of the heating test section is changed by adjusting the power of the electric heating system. When the inlet flow rate of the heating test section remains stable and the fluid temperature change at the inlet of the heating test section is within 0.5℃, a set of experimental data is recorded to calculate the thermal efficiency of the heating test section. Subsequently, the input power of the electric heating element of the heating test section is adjusted according to the experimental requirements, and preparations are made for data acquisition. Specifically, signals such as flow rate, pressure, pressure difference, and temperature are continuously acquired for approximately 60 seconds to complete one experimental condition.

[0048] Step 6: After completing part or all of the experimental conditions, slowly reduce the heating power of the electric heating wires in each part of the experimental circuit. When the temperature of each part of the experimental circuit drops to about 180℃, turn off the electromagnetic pump 105, keep the main power supply of the electromagnetic pump on, confirm that the gas circuit of the pressure stabilizing tank 104 and the lead storage tank 101 is connected, and open the valve of the outlet pipe of the lead storage tank. At this time, the liquid lead bismuth in the experimental circuit is returned to the lead storage tank 101, which is located at the lowest position in the experimental circuit, by gravity. To ensure that all the liquid lead bismuth in the experimental circuit is returned to the lead storage tank 101, the signal of the electromagnetic flowmeter 106 can be observed to gradually change from negative to zero, indicating that the liquid lead bismuth in the experimental circuit flows back into the lead storage tank 101. If the flowmeter shows a positive value to zero, it means that the liquid metal in the lead storage tank has been filled into the experimental circuit. When the reading of the electromagnetic flowmeter 106 is zero, it indicates that the liquid lead-bismuth in the experimental circuit has basically flowed back into the lead storage tank 101. The lead-bismuth valve of the lead storage tank outlet pipeline can be closed, and then all the electric heating equipment in the experimental circuit can be turned off, so that the temperature of the experimental circuit can be gradually reduced to room temperature, and the experiment ends.

Claims

1. An experimental apparatus for liquid lead-bismuth flow heat transfer with a static mass calibration device, characterized in that: It includes the main circuit for lead-bismuth thermal-hydraulic experiments, the electromagnetic flowmeter static mass calibration device, the electric heating system, the heat transfer oil cooling system, the gas system, and the data acquisition system; The main loop of the lead-bismuth thermal-hydraulic experiment consists of a lead storage tank (101), a heating test section (102), a shell-and-tube heat exchanger (103), a pressure stabilizing tank (104), an electromagnetic pump (105), and an electromagnetic flowmeter (106). Each piece of equipment is connected in sequence through a main pipeline. The components of the main loop of the lead-bismuth thermal-hydraulic experiment are arranged in layers. The lead storage tank (101) is used to heat and melt the lead-bismuth alloy. The heating test section (102) is used to simulate the fuel rods of the lead-bismuth fast reactor core. The pressure stabilizing tank (104) is used to maintain the pressure stability of the main loop when the electromagnetic flowmeter is calibrated. When the main loop is started, the high-temperature liquid lead-bismuth flows in sequence through the heating test section (102), the shell-and-tube heat exchanger (103), the pressure stabilizing tank (104), the electromagnetic pump (105), the electromagnetic flowmeter (106), and the commutator (201). After the experiment, the lead-bismuth flows back into the lead storage tank (101). The electromagnetic flowmeter static mass calibration device consists of a commutator (201), a lead-bismuth weighing tank (202), and a weighing device (203); the commutator (201) is used to adjust the flow of lead-bismuth to the main circuit or the lead-bismuth weighing tank (202); the lead-bismuth weighing tank (202) is used to load high-temperature liquid lead-bismuth, and the weighing device (203) is used to weigh the total mass flowing into the lead-bismuth weighing tank (202) within a specified calibration time; The electric heating system includes an electric heating rod, an electric heating wire, and a variable power regulator; the pipes and valves in the experimental device are wound with electric heating wire and controlled by the variable power regulator for preheating the circuit and lead-bismuth; the electric heating rod is installed in the heating test section (102) and the power is controlled by the variable power regulator to adjust the outlet temperature of the heating test section. The heat transfer oil cooling system consists of a shell-and-tube heat exchanger (103), an oil-water heat exchanger (301), a heat transfer oil tank (302), and a heat transfer oil pump (303). The heat transfer oil is pumped from the heat transfer oil tank (302) into the secondary side of the shell-and-tube heat exchanger (103) by the heat transfer oil pump (303). After being heated by the high-temperature liquid lead-bismuth on the primary side, the oil flows through the oil-water heat exchanger (301) and is cooled by the cooling water on the secondary side. It then returns to the heat transfer oil tank (302), completing the circulation of high-temperature heat transfer oil in the heat transfer oil cooling system. The gas system consists of an inert gas buffer tank (401) and a vacuum pump (402), which is used to extract a vacuum state in the loop and pressurize high-temperature liquid lead bismuth from the lead storage tank (101) into the main loop by inert gas replacement; The data acquisition system consists of a data acquisition card and temperature sensors, differential pressure sensors, and electromagnetic flowmeters (106) arranged in the main circuit. The data acquisition card transmits the measurement point parameters through the acquisition line, and the computer monitors and records the temperature, pressure, differential pressure, and flow parameters. The temperature sensor is located at the electric heating rod (506), the pressure sensor is arranged at both ends of the electric heating rod (506), and the electromagnetic flowmeter (106) is arranged between the electromagnetic pump (105) and the commutator (201), and is connected to the upstream and downstream equipment through pipelines. The experimental setup uses an electromagnetic pump (105) to provide the driving head for the main loop liquid lead-bismuth flow circulation, and an electromagnetic flowmeter (106) measures the output flow signal. The electromagnetic pump (105) adjusts its output power through a PI controller (701) to change the flow rate of the main loop liquid lead-bismuth. The flow signal output by the electromagnetic flowmeter (106) enters the PI controller (701), which controls the frequency of the electromagnetic pump (105) by judging the increase or decrease of the flow rate: when the flow rate increases, the frequency of the electromagnetic pump (105) is decreased to reduce the flow rate; when the flow rate decreases, the frequency of the electromagnetic pump (105) is increased to increase the flow rate, thereby maintaining a stable loop flow rate. The commutator (201) used in the static mass calibration device of the electromagnetic flowmeter is driven by a cylinder to change the position of the baffle. Before the calibration of the electromagnetic flowmeter (106) begins, the lead and bismuth are guided to the main circuit. During calibration, the commutator is reversed to guide the lead and bismuth to the weighing tank (202). After the calibration is completed, the commutator is reversed again to guide the lead and bismuth to the main circuit. The steps for calibrating an electromagnetic flowmeter using the static mass method are as follows: Step 1. The main circuit is started, the baffle of the commutator (201) is located on the main circuit side, and the liquid lead bismuth flows through the heating test section (102), shell and tube heat exchanger (103), pressure tank (104), electromagnetic pump (105), electromagnetic flowmeter (106), commutator (201) and returns to the heating test section (102) for circulation; Step 2. After the reading of the electromagnetic flowmeter (106) stabilizes, record the reading and start calibration. The baffle of the commutator (201) moves to the lead-bismuth weighing tank side and starts timing. Liquid lead-bismuth flows through the commutator (201) into the lead-bismuth weighing tank (202). Step 3. When the specified calibration time is reached, the calibration ends, the baffle of the commutator (201) moves to the main circuit side and the timing ends, and the liquid lead bismuth flows through the commutator (201) into the main circuit pipeline for circulation; Step 4. After the reading of the weighing device (203) stabilizes, record the reading. Calculate the mass flow rate from the specified calibration time and the net mass of the collected liquid lead and bismuth and record it. Step 5. Change the main circuit flow rate by changing the frequency of the electromagnetic pump (105), repeat the above calibration process, and obtain the relationship curve between the reading of the electromagnetic flowmeter (106) and the main circuit flow rate to complete the calibration of the electromagnetic flowmeter (106).

2. The experimental apparatus for liquid lead-bismuth flow heat transfer with a static mass calibration device according to claim 1, characterized in that: The heating test section (102) is a 7-bar bundle test section, including a test section (501). The test section (501) is connected to the upper chamber (502) and the lower chamber (503). The 7 electric heating rods (506) inside the hexagonal sleeve of the test section (501) are fixed by the positioning grid (504).

3. The experimental apparatus for liquid lead-bismuth flow heat transfer with a static mass calibration device according to claim 1, characterized in that: Before the circuit is started, the lead storage tank (101) melts the lead and bismuth into a liquid state in it through an electric heating rod, and is driven into the main circuit of the lead and bismuth thermal-hydraulic experiment by the pressure difference of the inert gas.

4. The experimental apparatus for liquid lead-bismuth flow heat transfer with a static mass calibration device according to claim 1, characterized in that: The electromagnetic flowmeter static mass calibration device adopts the static mass method, that is, within the calibration time interval, the net mass of the collected liquid lead bismuth is calculated based on the weights obtained before and after the liquid lead bismuth enters the lead bismuth weighing tank (202) through the commutator (201), thereby obtaining the main circuit mass flow rate and calibrating the electromagnetic flowmeter (106). After the calibration is completed, the reading is recorded after the reading of the weighing device (203) stabilizes.

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