Experimental device and method for rupture of heat transfer tubes in steam generators

Abstract

The invention relates to an experimental device and an experimental method for the rupture of a heat transfer tube of a steam generator. The invention relates to the technical field of lead-based reactors, and in particular to a simulation device and a simulation method for the rupture of a heat transfer tube of a steam generator. The simulation device comprises a reaction vessel and a water injection pipe; the reaction vessel is used to contain liquid lead or liquid lead-bismuth, a mounting hole is provided on the top of the reaction vessel, the water injection pipe is sealed and matched with the mounting hole, the inner end of the water injection pipe is used to extend below the liquid level in the reaction vessel, and a water injection port is provided at a portion of the water injection pipe close to the inner end, and the water injection pipe is used to guide high-pressure supercooled water to the water injection port. The simulation method comprises: injecting liquid lead or liquid lead-bismuth into the reaction vessel; and injecting high-pressure supercooled water from top to bottom below the liquid level of the reaction vessel. The simulation device and simulation method for the rupture of a heat transfer tube of a steam generator provided by the invention can simulate a more realistic physical process of a lead-based reactor SGTR accident, and help to accurately reveal the reaction mechanism of liquid lead or liquid lead-bismuth and water under the lead-based reactor SGTR accident condition.

Description

Technical Field

[0001] The present invention relates to the technical field of lead-based reactors, and in particular to a simulation device and a simulation method for the rupture of a heat transfer tube of a steam generator. Background Art

[0002] Lead-based reactors mainly refer to fast neutron reactors that use liquid pure lead or lead-bismuth eutectic alloy (Lead Bismuth Eutectic, LBE) as coolant. The steam generator in the lead-based reactor is the same as the traditional water reactor. It is a key component responsible for transferring heat in the reactor system. The core nuclear heat is brought to the wall of the heat transfer tube through lead or lead-bismuth alloy, and then transferred to the water in the secondary circuit. The water evaporates and produces saturated steam to drive the steam turbine to generate electricity. In the design of conventional pool-type lead-based reactors, the heat transfer tube of the steam generator is an important pressure-bearing boundary and radioactive protection boundary. Lead or lead-bismuth alloy frequently passes through the heat transfer tube for nuclear heat exchange, which means frequent flow. Frequent flow will aggravate the corrosion of lead and bismuth to structural materials. In addition, the thermal stress and mechanical stress caused by the huge temperature difference and pressure difference inside and outside the heat transfer tube, and the mechanical vibration caused by the fast-flowing fluid on both sides, all make the heat transfer tube structural materials operate in an extremely harsh environment. The experience of existing mature reactors (mainly nuclear submarines) and experimental loops has also confirmed the high probability of steam generator heat transfer tube rupture accidents in lead-based fast reactors. Therefore, steam generator heat transfer tube rupture (SGTR) accidents in lead-based reactors have been listed as core design basis accidents of lead-based fast reactors.

[0003] Although the chemical properties of lead and lead-bismuth alloys are stable, the water introduced by the SGTR accident will not undergo violent chemical reactions like molten salt reactors or sodium-cooled reactors, but there is still a violent interaction (Coolant-Coolant Interaction, CCI) between the two coolants of lead or lead-bismuth alloy and water in the lead-based reactor SGTR accident. In actual accidents, the pressure difference causes the high-pressure water in the heat transfer tube to spray toward the coolant, but the temperature difference causes both the supercooled water and the coolant to undergo huge temperature transients. The following phenomena may be caused: (1) high-pressure supercooled water forms a critical flow from the rupture of the heat transfer tube, generating a shock wave under the water hammer effect, which further causes mechanical pressure on the heat transfer tube and expands the rupture of the heat transfer tube; (2) high-pressure supercooled water quickly exchanges heat with high-temperature lead or lead-bismuth alloy, and the supercooled water quickly vaporizes to form bubbles. Due to the large density and viscosity of lead and lead-bismuth alloy, the bubbles are difficult to sustain and quickly break and disperse into small bubbles and float up quickly, which may entrain some liquid lead or lead-bismuth alloy; (3) lead or lead-bismuth alloy closer to the injection port instantly loses a large amount of heat and begins to form condensation nuclei. As the liquid continues to be injected into the heat transfer tube, the lead or lead-bismuth alloy continues to lose heat, the condensation nuclei begin to crystallize, and part of the coolant appears solidified and sinks in solid form.

[0004] At present, there are some devices that simulate the rupture of heat transfer tubes in steam generators in lead-based reactors. However, the physical processes simulated by these devices do not conform to the physical processes of real lead-based reactor SGTR accidents, and cannot accurately reveal the reaction mechanism of lead / lead-bismuth and water under lead-based reactor SGTR accident conditions.

[0005] In summary, how to overcome the above-mentioned defects of the existing device for simulating the rupture of the heat transfer tube of the steam generator in the lead-based reactor is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0006] The purpose of the present invention is to provide a simulation device and a simulation method for the rupture of a heat transfer tube of a steam generator in a lead-based reactor, so as to alleviate the technical problem that the device for simulating the rupture of a heat transfer tube of a steam generator in a lead-based reactor in the prior art cannot simulate the physical process of a real lead-based reactor SGTR accident.

[0007] The device for simulating the rupture of a heat transfer tube of a steam generator provided by the present invention comprises a reaction container and a water injection pipe.

[0008] The reaction container is used to contain liquid lead or liquid lead-bismuth. A mounting hole is provided on the top of the reaction container. The water injection pipe is sealed and matched with the mounting hole. The inner end of the water injection pipe is used to extend below the liquid level in the reaction container, and a water injection port is provided near the inner end of the water injection pipe. The water injection pipe is used to guide high-pressure supercooled water to the water injection port.

[0009] Preferably, as an implementable embodiment, a back pressure valve is installed on the water injection pipe;

[0010] And / or, a flow control valve is installed on the water injection pipe;

[0011] And / or, a check valve is installed at the water injection port, and the check valve is used to prevent liquid lead or liquid lead-bismuth from entering the water injection pipe;

[0012] And / or, the water injection pipe is connected to a supercooled water container, and the supercooled water container has a preheating device for preheating the supercooled water;

[0013] And / or, the water injection pipe is detachably connected to the reaction container.

[0014] Preferably, as an implementation method, a gas injection port and an exhaust port are provided on the reaction container, the gas injection port is used to be connected to a gas supply device for supplying an inert gas, a first stop valve is installed at the gas injection port, and a safety valve is installed at the exhaust port;

[0015] And / or, the reaction container is provided with a heater, and the heater is used to heat the liquid lead or liquid lead bismuth in the reaction container;

[0016] And / or, the reaction container comprises a cylinder, an upper head and a lower head, and the upper head and the lower head are respectively sealed at two end openings of the cylinder.

[0017] Preferably, as an implementable embodiment, a lead injection port is opened on the reaction container, and the lead injection port is used to be sealed and connected to a lead liquid pipeline, and the lead liquid pipeline is used to be connected to a feeding device for supplying liquid lead or liquid lead bismuth.

[0018] Preferably, as an implementable embodiment, the lead liquid pipeline is located below the reaction container, and the lead liquid pipeline has a liquid inlet section, a reciprocating section and a recovery section, one end of the reciprocating section is connected to the lead injection port, the liquid outlet end of the liquid inlet section and the liquid inlet section of the recovery section are both connected to the other end of the reciprocating section, the liquid inlet section is used to be connected to the feeding device, and the recovery section is used to be connected to the waste liquid container, the reciprocating section is equipped with a second stop valve, and the recovery section is equipped with a third stop valve.

[0019] Preferably, as an implementable embodiment, the simulation device further comprises an ultrasonic Doppler system, the ultrasonic Doppler system comprises an ultrasonic probe and a data processor, the ultrasonic probe is used to detect the fluid signal in the reaction container, and the ultrasonic probe is electrically connected to the data processor;

[0020] The ultrasonic probe is mounted on the outer surface of the reaction container by a clamp, and / or the ultrasonic probe is surrounded by a water cooling pipeline, and / or the ultrasonic probe is multiple and dispersed.

[0021] Preferably, as an implementable embodiment, the simulation device further comprises a pressure processor and a pressure sensor, the reaction container is provided with a pressure measuring port, the pressure sensor is installed at the pressure measuring port, and the pressure sensor is electrically connected to the pressure processor;

[0022] And / or, the simulation device further comprises a temperature processor and a thermocouple, wherein the thermocouple is installed in the reaction container, a probe of the thermocouple extends into the interior of the reaction container, and the probe of the thermocouple is extended toward the water injection port.

[0023] The present invention also provides a method for simulating the rupture of a heat transfer tube of a steam generator, the method comprising:

[0024] injecting liquid lead or liquid lead-bismuth into the reaction container;

[0025] High-pressure supercooled water is injected from top to bottom below the liquid level of the reaction vessel.

[0026] Preferably, as an implementable method, before the step of injecting liquid lead or liquid lead-bismuth into the reaction container, the simulation method further comprises: opening a first stop valve at the gas injection port of the reaction container, continuously injecting an inert gas into the reaction container, so that the air in the reaction container is discharged through the safety valve, and maintaining the pressure in the reaction container;

[0027] And / or, the step of injecting liquid lead or liquid lead-bismuth into the reaction container comprises: opening a second stop valve between the lead injection port of the reaction container and the feeding device, and closing the second stop valve after the liquid level in the reaction container reaches a predetermined liquid level;

[0028] And / or, after the reaction of the liquid lead or liquid lead-bismuth with the supercooled water is completed, the simulation method further comprises: first opening a third stop valve connected between the bottom lead injection port of the reaction container and the waste liquid container, and then opening a second stop valve connected between the lead injection port of the reaction container and the third stop valve to allow the waste liquid to flow into the waste liquid container;

[0029] And / or, the step of injecting high-pressure supercooled water from top to bottom below the liquid level of the reaction container comprises: opening a back pressure valve on a water injection pipe, so that the supercooled water in the supercooled water container is injected into the liquid lead or liquid lead-bismuth from top to bottom through the back pressure valve, until the water injection amount reaches a predetermined water injection amount;

[0030] And / or, the simulation method further comprises: during the reaction of liquid lead or liquid lead bismuth with supercooled water and during the discharge of waste liquid, the heater on the reaction container is continuously heated.

[0031] Preferably, as an implementable method, the simulation method further comprises: during the reaction of liquid lead or liquid lead-bismuth with supercooled water, the ultrasonic probe detects the signal inside the reaction container, and transmits the detected signal to a data processor, the data processor processes the received signal to obtain the fluid density, liquid flow rate, cavitation fraction, cavitation distribution and / or cavitation movement speed in the reaction container;

[0032] And / or, the simulation method further comprises: during the reaction of liquid lead or liquid lead-bismuth with supercooled water, the pressure sensor detects the pressure in the reaction container, and transmits the detected pressure signal to the pressure processor, the pressure processor processes the received pressure signal to obtain the pressure distribution value in the reaction container along the height direction;

[0033] And / or, the simulation method also includes: during the reaction of liquid lead or liquid lead bismuth with supercooled water, the thermocouple detects the temperature signal of the heat transfer characteristic point in the reaction container, and transmits the detected temperature signal to the temperature processor, the temperature processor processes the received temperature signal to obtain the temperature response curve of the heat transfer characteristic point.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] In the simulation device for rupture of a heat transfer tube of a steam generator provided by the present invention, a water injection pipe is inserted into the reaction container through a mounting hole at the top of the reaction container, and extends from top to bottom to below the liquid level of liquid lead or liquid lead-bismuth in the reaction container. The water injection pipe is equivalent to the heat transfer tube of the steam generator, and the water injection port opened at the inner end of the water injection pipe is equivalent to the rupture on the heat transfer tube.

[0036] When conducting a simulation experiment of heat transfer tube rupture, liquid lead or liquid lead-bismuth is first injected into the reaction container, and then high-pressure supercooled water is allowed to flow from top to bottom along the water injection pipe toward the water injection port at the inner end of the water injection pipe. After reaching the water injection port, the high-pressure supercooled water will be sprayed into the liquid lead or liquid lead-bismuth. In this way, a more realistic physical process of a lead-based reactor SGTR accident can be simulated, which in turn helps to accurately reveal the reaction mechanism of lead / lead-bismuth and water under the lead-based reactor SGTR accident conditions.

[0037] The simulation method for the rupture of the heat transfer tube of the steam generator provided by the present invention also injects liquid lead or liquid lead-bismuth into the reaction container in advance, and then injects high-pressure supercooled water from top to bottom below the liquid surface of the reaction container, that is, the high-pressure supercooled water will be sprayed from top to bottom into the liquid lead or liquid lead-bismuth, which can simulate a more realistic physical process of the lead-based reactor SGTR accident, and help to accurately reveal the reaction mechanism of liquid lead or liquid lead-bismuth and water under the lead-based reactor SGTR accident condition. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0039] Figure 1 A schematic cross-sectional view of a device for simulating the rupture of a heat transfer tube of a steam generator provided in an embodiment of the present invention;

[0040] Figure 2 A schematic cross-sectional structural diagram of another cross-sectional surface of the device for simulating the rupture of a heat transfer tube of a steam generator provided by an embodiment of the present invention;

[0041] Figure 3 A top view of a simulation device for rupture of a heat transfer tube of a steam generator provided by an embodiment of the present invention;

[0042] Figure 4 A bottom view of a device for simulating the rupture of a heat transfer tube of a steam generator provided by an embodiment of the present invention.

[0043] Description of reference numerals:

[0044] 100-reaction container; 110-first stop valve; 120-safety valve;

[0045] 200-water injection pipe; 210-back pressure valve; 220-check valve;

[0046] 300-heater;

[0047] 400-lead liquid pipeline; 410-liquid inlet section; 420-round trip section; 421-second stop valve; 430-recovery section; 431-third stop valve;

[0048] 500-pressure sensor;

[0049] 600-thermocouple;

[0050] 700-waste tank;

[0051] 800-stand. DETAILED DESCRIPTION

[0052] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "upper", "lower", "top", "bottom", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0054] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0055] The present invention is further described in detail below through specific implementation examples in conjunction with the accompanying drawings.

[0056] See also Figure 1 and Figure 2The present embodiment provides a simulation device for the rupture of a heat transfer tube of a steam generator, which includes a reaction vessel 100 and a water injection pipe 200; the reaction vessel 100 is used to contain liquid lead or liquid lead-bismuth, a mounting hole is provided on the top of the reaction vessel 100, the water injection pipe 200 is sealed with the mounting hole, the inner end of the water injection pipe 200 is used to extend below the liquid level in the reaction vessel 100, and a water injection port is provided at a portion near the inner end of the water injection pipe 200, and the water injection pipe 200 is used to guide high-pressure supercooled water to the water injection port.

[0057] In the simulation device for the rupture of the heat transfer tube of the steam generator provided in this embodiment, the water injection pipe 200 is inserted into the reaction vessel 100 through the installation hole on the top of the reaction vessel 100, and extends from top to bottom below the liquid level of the liquid lead or liquid lead-bismuth in the reaction vessel 100. The water injection pipe 200 is equivalent to the heat transfer tube of the steam generator, and the water injection port opened near the inner end of the water injection pipe 200 is equivalent to the rupture on the heat transfer tube.

[0058] When conducting a simulation experiment of heat transfer tube rupture, liquid lead or liquid lead-bismuth is first injected into the reaction vessel 100, and then high-pressure supercooled water is allowed to flow from top to bottom along the water injection pipe 200 toward the water injection port near the inner end of the water injection pipe 200. After reaching the water injection port, the high-pressure supercooled water will be sprayed into the liquid lead or liquid lead-bismuth. In this way, a more realistic physical process of a lead-based reactor SGTR accident can be simulated, which in turn helps to accurately reveal the reaction mechanism of lead / lead-bismuth and water under the lead-based reactor SGTR accident condition.

[0059] Specifically, a back pressure valve 210 may be installed on the water injection pipe 200. Thus, under the action of the back pressure valve 210, the water pressure of the supercooled water can reach the target pressure, thereby more realistically simulating the physical process of high-pressure supercooled water spraying toward liquid lead or liquid lead-bismuth.

[0060] Specifically, a flow control valve may be added to the water injection pipe 200, so that supercooled water can be quantitatively injected into the liquid lead or liquid lead-bismuth.

[0061] Preferably, a check valve 220 can be installed at the water injection port, and the check valve 220 is used to prevent liquid lead or liquid lead bismuth from entering the water injection pipe 200. The presence of the check valve 220 will not affect the physical process of high-pressure supercooled water being ejected from the water injection port, nor will it affect the flow field outside the water injection pipe 200, and the authenticity is higher.

[0062] Furthermore, the water injection pipe 200 can be connected to the supercooled water container, and a preheating device for preheating the supercooled water can be provided on the supercooled water container. In this way, the preheating device can be used to preheat the supercooled water in the supercooled water container so that the temperature of the supercooled water reaches the actual temperature of the liquid lead or liquid lead bismuth when the heat transfer tube ruptures, thereby improving the authenticity.

[0063] Preferably, the water injection pipe 200 can be connected to the reaction container 100 in a detachable manner, so that a suitable water injection pipe 200 can be installed in the installation hole of the reaction container 100 according to experimental requirements.

[0064] The positions of the water injection ports on different water injection pipes 200 may be different, for example, they may be opened on the end face or side of the water injection pipe 200. In this way, water injection pipes 200 with different water injection port positions may be selected as needed to simulate heat transfer tube rupture accidents when the rupture faces different directions.

[0065] The water injection pipe 200 can be a straight pipe or a curved pipe with different lengths or bending directions. A straight pipe or a curved pipe can be selected according to needs to simulate a heat transfer pipe rupture accident at different rupture positions.

[0066] The diameters of the water injection ports on different water injection pipes 200 may be different. Thus, water injection pipes 200 with different diameters of water injection ports may be selected as required to simulate heat transfer pipe rupture accidents with different rupture sizes.

[0067] An injection port and an exhaust port are provided on the reaction vessel 100, and the injection port is connected to a gas supply device for supplying an inert gas. A first stop valve 110 is installed at the injection port. Before the experiment begins, the first stop valve 110 can be opened first, and the inert gas can be injected into the reaction vessel 100 through the injection port using the gas supply device to discharge the air in the reaction vessel 100, thereby ensuring the stability of the experimental process and preventing oxidation reaction from occurring under high temperature. This is not only closer to the physical process when a real accident occurs, but also can reduce damage to structures such as the reaction vessel 100 and the water injection pipe 200, thereby extending the service life of the device.

[0068] A safety valve 120 may be installed at the exhaust port, so that during the process of injecting inert gas, the pressure in the reaction vessel 100 will gradually increase until it reaches the maximum pressure that the safety valve 120 can withstand. The safety valve 120 then opens, and air and excess inert gas are discharged from the safety valve 120. In this way, a predetermined pressure can be maintained in the reaction vessel 100, thereby simulating a real reaction environment.

[0069] Specifically, the pressure in the reaction container 100 may be adjusted by adjusting the limit pressure of the safety valve 120 .

[0070] Preferably, the above-mentioned gas injection port and exhaust port are both opened at the top of the reaction vessel 100. In this way, after liquid lead or liquid lead bismuth is injected into the reaction vessel 100, the liquid lead or liquid lead bismuth will not block the gas injection port and the exhaust port, which is convenient for continuously injecting inert gas from the gas injection port during the reaction process, and excess gas can also be smoothly discharged from the exhaust port, so that the pressure in the reaction vessel 100 can be maintained within a suitable range during the reaction process.

[0071] The inert gas may be argon.

[0072] Specifically, a heater 300 may be provided on the reaction vessel 100, so as to utilize the heater 300 to continuously heat the liquid lead or liquid lead bismuth in the reaction vessel 100, maintain the temperature of the liquid lead or liquid lead bismuth, and prevent the liquid lead or liquid lead bismuth from solidifying. Meanwhile, the reaction temperature of the liquid lead or liquid lead bismuth may also be maintained in the event of an accident, thereby ensuring the smooth progress and authenticity of the experiment.

[0073] Specifically, the reaction vessel 100 comprises a cylinder, an upper head and a lower head, and the upper head and the lower head are respectively sealed at the two end openings of the cylinder, so that a sealed cavity can be formed to contain liquid lead or liquid lead-bismuth.

[0074] The reaction vessel 100 can be supported by a stand 800, which can fix the reaction vessel 100 and raise the reaction vessel 100 to a certain height, so as to facilitate the connection of other structures under the reaction vessel 100; the stand 800 includes a base frame and a support, the base frame is used to be placed on the ground or other supporting platforms, the support is installed on the base frame, and the reaction vessel 100 is installed on the support.

[0075] Specifically, a lead injection port can be opened on the reaction vessel 100, and the lead liquid pipe 400 is sealed and connected at the lead injection port, and the lead liquid pipe 400 is connected to a feeding device for supplying liquid lead or liquid lead bismuth. In this way, there is no need to open the reaction vessel 100, and the liquid lead or liquid lead bismuth can be directly injected into the reaction vessel 100 using the feeding device.

[0076] Specifically, the above-mentioned lead liquid pipeline 400 is located above the reaction container 100, and the lead liquid pipeline 400 has a liquid inlet section 410, a reciprocating section 420 and a recovery section 430. One end of the reciprocating section 420 is connected to the lead injection port, and the liquid outlet end of the liquid inlet section 410 and the liquid inlet end of the recovery section 430 are both connected to the other end of the reciprocating section 420, wherein the liquid inlet section 410 is connected to the feeding device, and the recovery section 430 is connected to the waste liquid container. At the same time, a second stop valve 421 is installed on the reciprocating section 420, and a third stop valve 431 is installed on the recovery section 430.

[0077] Before the simulation experiment begins, first open the second stop valve 421, and use the feeding device to inject liquid lead or liquid lead-bismuth into the reaction vessel 100 from the liquid inlet section 410 and the reciprocating section 420 until the amount required for the reaction is reached, and then close the second stop valve 421; after the simulation experiment is completed, the third stop valve 431 and the second stop valve 421 can be opened. At this time, the waste liquid in the reaction vessel 100 can flow into the waste liquid container under the action of its own gravity, thereby realizing the recovery of the waste liquid.

[0078] Specifically, the liquid outlet end of the liquid inlet section 410 and the liquid inlet end of the recovery section 430 may be connected to the reciprocating section 420 via a three-way pipe fitting.

[0079] The second stop valve 421 is a high-pressure valve.

[0080] In addition, an ultrasonic Doppler system can be added to the simulation device provided in this embodiment. The ultrasonic Doppler system includes an ultrasonic probe and a data processor, wherein the ultrasonic probe can detect the fluid (including liquid lead or liquid lead bismuth, water and bubbles) signal in the reaction container 100, and the ultrasonic probe and the data processor are electrically connected so that the ultrasonic probe can transmit the detected signal to the data processor for analysis and processing by the data processor.

[0081] Liquid lead or liquid lead bismuth has different acoustic impedances from water and water vapor, and echoes will be generated at the interface where the acoustic impedance suddenly changes. According to the echo time and the change in the sound wave amplitude, the propagation distance and the interface reflection coefficient can be determined, thereby obtaining the acoustic impedance information of each component. Acoustic impedance = medium density × medium sound speed. Since the density difference between liquid lead or liquid lead bismuth and water and water vapor is very large, the acoustic impedance value difference is very large, so the interface between liquid lead or liquid lead bismuth, water and water vapor can be clearly distinguished, thereby achieving the imaging purpose and realizing the visualization of complex phase changes; in addition, when the emitted fixed-frequency ultrasonic wave acts on droplets or bubbles, reflection will be formed. Due to the different fluid velocity size and direction, the reflected signal frequency will also be different. After mathematical processing, the multiphase flow velocity distribution can be obtained. In summary, the ultrasonic Doppler system can obtain the fluid density, liquid flow rate, cavitation fraction, cavitation distribution and / or cavitation movement speed in the reaction vessel 100.

[0082] Specifically, the ultrasonic probe is mounted on the outer surface of the reaction vessel 100 by a clamp. Compared with fixing the ultrasonic probe by gluing, the clamp fixation can reduce the probability of the ultrasonic probe falling due to the failure of glue under high temperature, thereby improving reliability.

[0083] Preferably, a water cooling pipeline is surrounded around the ultrasonic probe, and the ultrasonic probe is cooled by the water cooling pipeline to cope with the influence of the high temperature of the reaction container 100 on the ultrasonic probe, thereby improving the working reliability of the ultrasonic probe.

[0084] The ultrasonic probe can be made of high temperature resistant materials.

[0085] The number of ultrasonic probes may be multiple, and the multiple ultrasonic probes may be dispersedly arranged, so that ultrasonic detection may be performed on multiple areas in the reaction container 100, thereby facilitating the acquisition of rich data.

[0086] Specifically, a landmark detection point can be obtained through simulation, and a plurality of ultrasonic detections can be arranged at each landmark detection point. In this way, the three-dimensional complex phase change of the multiphase flow can be visualized, and the information of each position in the reaction vessel 100 can be obtained.

[0087] A pressure processor and a pressure sensor 500 may be additionally provided in the simulation device provided in the present embodiment. Accordingly, a pressure measuring port is opened on the reaction vessel 100, and the pressure sensor 500 is installed on the pressure measuring port, so that the pressure sensor 500 can be used to sense the pressure inside the reaction vessel 100. The pressure sensor 500 is electrically connected to the pressure processor, and the pressure processor can process the pressure sensed by the pressure sensor 500. By calculating based on the pressure transmission principle, the average pressure at different heights inside the entire reaction vessel 100 can be obtained.

[0088] Preferably, the pressure measuring port is opened at the top of the reaction vessel 100, which has higher sensitivity and is not easily affected by liquid lead or liquid lead bismuth.

[0089] See also Figure 1-Figure 4 In the simulation device provided in this embodiment, a temperature processor and a thermocouple 600 may be additionally provided. The thermocouple 600 is installed in the reaction container 100, and the probe of the thermocouple 600 is extended into the interior of the reaction container 100 so as to use the thermocouple 600 to detect the temperature of the corresponding position during the experiment.

[0090] The probe of the thermocouple 600 is preferably extended toward the water injection port, that is, the extension direction of the probe is consistent with the flow direction of high-pressure supercooled water after being ejected from the water injection port. In this way, the influence of the probe of the thermocouple 600 on the flow field can be reduced, and the authenticity of the simulation experiment can be improved.

[0091] Specifically, a characteristic heat transfer point with a mark may be obtained according to the simulation, and the detection end of the thermocouple 600 may be arranged at the location of the characteristic heat transfer point.

[0092] The thermocouple 600 may be a high temperature resistant platinum-rhodium thermocouple 600.

[0093] In this embodiment, all pipes for guiding liquid lead or liquid lead-bismuth can be configured as pipes with heating and heat preservation functions to prevent the liquid lead or liquid lead-bismuth from cooling and solidifying during the transportation process.

[0094] This embodiment also provides a method for simulating the rupture of a heat transfer tube of a steam generator, which comprises the following steps:

[0095] S102, injecting liquid lead or liquid lead bismuth into the reaction container 100;

[0096] S104, high-pressure supercooled water is injected from top to bottom below the liquid level of the reaction container 100.

[0097] The high-pressure supercooled water is sprayed from top to bottom into the liquid lead or liquid lead-bismuth, which can simulate a more realistic physical process of a lead-based reactor SGTR accident, and help to accurately reveal the reaction mechanism of liquid lead or liquid lead-bismuth and water under the lead-based reactor SGTR accident conditions.

[0098] Before step S102, the simulation method provided in this embodiment may also include step S101: opening the first stop valve 110 at the gas injection port of the reaction vessel 100, continuously injecting inert gas into the reaction vessel 100, so that the air in the reaction vessel 100 is discharged from the safety valve 120, and the pressure in the reaction vessel 100 is maintained, so as to ensure the stability of the experimental process and prevent oxidation reaction from occurring under high temperature. This is not only closer to the physical process when a real accident occurs, but also can reduce damage to structures such as the reaction vessel 100 and the water injection pipe 200, thereby extending the service life of the device.

[0099] The above-mentioned step S102 may specifically include: opening the second stop valve 421 between the lead filling port of the reaction container 100 and the feeding device, and closing the second stop valve 421 after the liquid level in the reaction container 100 reaches a predetermined liquid level. In this way, there is no need to open the reaction container 100, and the liquid lead or liquid lead-bismuth can be directly injected into the reaction container 100 using the feeding device.

[0100] After the reaction of liquid lead or liquid lead bismuth with supercooled water is completed, the third stop valve 431 connected between the bottom lead injection port of the reaction vessel 100 and the waste liquid container can be opened first, and then the second stop valve 421 connected between the lead injection port of the reaction vessel 100 and the third stop valve 431 can be opened to allow the waste liquid to flow into the waste liquid container.

[0101] It should be noted that the second stop valve 421 is the pressure boundary of the reaction vessel 100. If it is opened first, the high pressure will be brought to the area below, which reduces the safety. Therefore, opening the third stop valve 431 first can improve safety. In addition, opening the third stop valve 431 first can reduce the adhesion of lead or lead-bismuth on the second stop valve 421 and the third stop valve 431, reduce the cleaning burden, and reduce the probability of the second stop valve 421 and the third stop valve 431 being blocked.

[0102] The above-mentioned step S104 may specifically include: opening the back pressure valve 210 on the water injection pipe 200, so that the supercooled water in the supercooled water container is injected into the liquid lead or liquid lead bismuth from top to bottom through the back pressure valve 210, until the water injection amount reaches the predetermined water injection amount. In this way, under the action of the back pressure valve 210, the water pressure of the supercooled water can reach the target pressure, thereby more realistically simulating the physical process of high-pressure supercooled water spraying into liquid lead or liquid lead bismuth.

[0103] During the reaction of liquid lead or liquid lead-bismuth with supercooled water, the heater 300 on the reaction vessel 100 is continuously heated to maintain the temperature of the liquid lead or liquid lead-bismuth to prevent the liquid lead or liquid lead-bismuth from solidifying. At the same time, the reaction temperature of the liquid lead or liquid lead-bismuth can also be maintained in the event of an accident, thereby ensuring the smooth progress and authenticity of the experiment.

[0104] During the waste liquid discharge process, the heater 300 on the reaction container 100 is continuously heated to maintain the temperature of the liquid lead or liquid lead-bismuth, prevent the liquid lead or liquid lead-bismuth from solidifying, ensure normal waste discharge, reduce the probability of pipeline blockage, and improve the thoroughness of waste discharge.

[0105] During the reaction of liquid lead or liquid lead-bismuth with supercooled water, step S106 may be added: an ultrasonic probe detects the signal inside the reaction vessel 100, and transmits the detected signal to a data processor, which processes the received signal to obtain the fluid density, liquid flow rate, cavitation fraction, cavitation distribution and / or cavitation movement speed in the reaction vessel 100.

[0106] In addition, step S108 may be added: the pressure sensor 500 detects the pressure in the reaction container 100 and transmits the detected pressure signal to the pressure processor, which processes the received pressure signal to obtain the pressure distribution value along the height direction in the reaction container 100.

[0107] Step S110 may also be added: the thermocouple 600 detects the temperature signal of the heat transfer characteristic point in the reaction container 100, and transmits the detected temperature signal to the temperature processor, which processes the received temperature signal to obtain a temperature response curve of the heat transfer characteristic point.

[0108] In order to further explain the present invention in more detail, a more specific example is now given as follows:

[0109] Step S201, experiment preparation stage, open the first stop valve 110 at the gas injection port of the reaction container 100, so that the gas supply device can inject argon into the reaction container 100, empty the oxygen in the tank, and the excess argon is discharged from the safety valve 120 to maintain the pressure in the container;

[0110] Step S202, preheating the lead / lead-bismuth into a liquid state, opening the second stop valve 421, and allowing the lead / lead-bismuth to enter the reaction vessel 100 from the liquid inlet through the lead liquid pipeline 400;

[0111] Step S203, turning on the electric heater 300 on the reaction vessel 100 to maintain the temperature at which the lead / lead-bismuth melts;

[0112] Step S204, preheating supercooled water;

[0113] Step S205, at the beginning of the experiment, the back pressure valve 210 and the flow control valve connected to the preheating water tank are opened to inject water into the hot lead / lead-bismuth at a constant pressure and in a quantitative manner;

[0114] Step S206, start the ultrasonic Doppler system, use the phased array ultrasonic detector to detect the movement of the multiphase flow in the container, and obtain the fluid density, liquid flow rate, cavitation fraction, cavitation distribution and / or cavitation movement speed in the reaction container 100;

[0115] Step S207, using the pressure sensor 500 to measure the pressure near the top of the reaction container 100, and analyzing it through the pressure processor to obtain the pressure inside the reaction container 100;

[0116] Step S208, using the thermocouple 600 to measure the temperature of the heat transfer characteristic point in the reaction container 100, and analyzing it through the temperature processor to obtain the temperature in the reaction container 100;

[0117] Step S209, after the reaction is finished, the third stop valve 431 and the second stop valve 421 are opened successively, and the waste liquid flows into the waste liquid tank 700. During the recovery process, the electric heater 300 is kept turned on, and argon gas is continuously passed to exhaust the reaction container 100.

[0118] In summary, the embodiments of the present invention disclose a simulation device and method for the rupture of a heat transfer tube of a steam generator, which overcomes many technical defects of the traditional simulation device for the rupture of a heat transfer tube of a steam generator. The simulation device and method for the rupture of a heat transfer tube of a steam generator provided by the embodiments of the present invention can simulate a more realistic physical process of a lead-based reactor SGTR accident, which helps to accurately reveal the reaction mechanism of liquid lead or liquid lead-bismuth with water under the lead-based reactor SGTR accident condition.

[0119] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A simulation device for rupture of a heat transfer tube of a steam generator, characterized in that: It comprises a reaction container (100) and a water injection pipe (200); The reaction container (100) is used to contain liquid lead or liquid lead-bismuth. A mounting hole is provided on the top of the reaction container (100). The water injection pipe (200) is sealed and matched with the mounting hole. The inner end of the water injection pipe (200) is used to extend below the liquid level in the reaction container (100). A water injection port is provided at a portion of the water injection pipe (200) close to the inner end. The water injection pipe (200) is used to guide high-pressure supercooled water to the water injection port.

2. The simulation device according to claim 1, characterized in that A back pressure valve (210) is installed on the water injection pipe (200); And / or, a flow control valve is installed on the water injection pipe (200); And / or, a check valve (220) is installed at the water injection port, and the check valve (220) is used to prevent liquid lead or liquid lead bismuth from entering the water injection pipe (200); And / or, the water injection pipe (200) is connected to a supercooled water container, and the supercooled water container has a preheating device for preheating the supercooled water; And / or, the water injection pipe (200) is detachably connected to the reaction container (100).

3. The simulation device according to claim 1, characterized in that The reaction container (100) is provided with a gas injection port and an exhaust port, the gas injection port is used to be connected to a gas supply device for supplying an inert gas, a first stop valve (110) is installed at the gas injection port, and a safety valve (120) is installed at the exhaust port; And / or, the reaction container (100) is provided with a heater (300), and the heater (300) is used to heat the liquid lead or liquid lead bismuth in the reaction container (100); And / or, the reaction container (100) comprises a cylinder, an upper head and a lower head, and the upper head and the lower head are respectively sealed at two end openings of the cylinder.

4. The simulation device according to claim 1, characterized in that The reaction container (100) is provided with a lead injection port, the lead injection port is used to be sealedly connected to a lead liquid pipeline (400), and the lead liquid pipeline (400) is used to be connected to a feeding device for supplying liquid lead or liquid lead bismuth.

5. The simulation device according to claim 4, characterized in that The lead liquid pipeline (400) is located below the reaction container (100), and the lead liquid pipeline (400) comprises a liquid inlet section (410), a reciprocating section (420) and a recovery section (430). One end of the reciprocating section (420) is connected to the lead injection port, and the liquid outlet end of the liquid inlet section (410) and the liquid inlet section (410) of the recovery section (430) are both connected to the other end of the reciprocating section (420). The liquid inlet section (410) is used to be connected to the feeding device, and the recovery section (430) is used to be connected to the waste liquid container. The reciprocating section (420) is provided with a second stop valve (421), and the recovery section (430) is provided with a third stop valve (431).

6. The simulation device according to any one of claims 1 to 5, characterized in that: The simulation device further comprises an ultrasonic Doppler system, wherein the ultrasonic Doppler system comprises an ultrasonic probe and a data processor, wherein the ultrasonic probe is used to detect fluid signals in the reaction container (100), and the ultrasonic probe is electrically connected to the data processor; The ultrasonic probe is mounted on the outer surface of the reaction container (100) via a clamp, and / or a water cooling pipeline is surrounded by the ultrasonic probe, and / or the ultrasonic probe is multiple and dispersed.

7. The simulation device according to any one of claims 1 to 5, characterized in that: The simulation device further comprises a pressure processor and a pressure sensor (500); a pressure measuring port is provided on the reaction container (100); the pressure sensor (500) is installed on the pressure measuring port; and the pressure sensor (500) is electrically connected to the pressure processor; And / or, the simulation device also includes a temperature processor and a thermocouple (600), wherein the thermocouple (600) is installed in the reaction container (100), the probe of the thermocouple (600) extends into the interior of the reaction container (100), and the probe of the thermocouple (600) is extended toward the water injection port.

8. A method for simulating the rupture of a heat transfer tube of a steam generator, characterized in that: The simulation method comprises: injecting liquid lead or liquid lead-bismuth into a reaction container (100); High-pressure supercooled water is injected from top to bottom below the liquid level of the reaction container (100).

9. The simulation method according to claim 8, characterized in that: Before the step of injecting liquid lead or liquid lead-bismuth into the reaction container (100), the simulation method further comprises: opening a first stop valve (110) at the gas injection port of the reaction container (100), continuously injecting an inert gas into the reaction container (100), allowing the air in the reaction container (100) to be discharged through the safety valve (120), and maintaining the pressure in the reaction container (100); And / or, the step of injecting liquid lead or liquid lead-bismuth into the reaction container (100) comprises: opening a second stop valve (421) between the lead injection port of the reaction container (100) and the feeding device, and closing the second stop valve (421) after the liquid level in the reaction container (100) reaches a predetermined liquid level; And / or, after the reaction of the liquid lead or liquid lead-bismuth with the supercooled water is completed, the simulation method further comprises: first opening a third stop valve (431) connected between the bottom lead injection port of the reaction container (100) and the waste liquid container, and then opening a second stop valve (421) connected between the lead injection port of the reaction container (100) and the third stop valve (431) to allow the waste liquid to flow into the waste liquid container; And / or, the step of injecting high-pressure supercooled water from top to bottom below the liquid level of the reaction container (100) comprises: opening the back pressure valve (210) on the water injection pipe (200) so that the supercooled water in the supercooled water container is injected from top to bottom into the liquid lead or liquid lead-bismuth through the back pressure valve (210) until the injection amount reaches a predetermined injection amount; And / or, the simulation method further comprises: during the reaction process of the liquid lead or liquid lead bismuth with the supercooled water and during the discharge of the waste liquid, the heater (300) on the reaction container (100) is continuously heated.

10. The simulation method according to claim 8 or 9, characterized in that: The simulation method further comprises: during the reaction process of liquid lead or liquid lead-bismuth with supercooled water, an ultrasonic probe detects a signal inside the reaction container (100), and transmits the detected signal to a data processor, the data processor processes the received signal to obtain a fluid density, a liquid flow rate, a cavitation fraction, a cavitation distribution and / or a cavitation movement speed inside the reaction container (100); And / or, the simulation method further comprises: during the reaction process of liquid lead or liquid lead-bismuth with supercooled water, the pressure sensor (500) detects the pressure in the reaction container (100), and transmits the detected pressure signal to the pressure processor, the pressure processor processes the received pressure signal, and obtains the pressure distribution value in the reaction container (100) along the height direction; And / or, the simulation method further comprises: during the reaction process of liquid lead or liquid lead bismuth and supercooled water, the thermocouple (600) detects the temperature signal of the heat transfer characteristic point in the reaction container (100), and transmits the detected temperature signal to a temperature processor, and the temperature processor processes the received temperature signal to obtain a temperature response curve of the heat transfer characteristic point.

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