Mass energy release system and method for simulating nuclear reactor accident

Abstract

The invention relates to a mass energy release system and method for simulating a nuclear reactor accident. The mass energy release system for simulating the nuclear reactor accident comprises a containment simulation body, a blowing simulation body and a steam generation device. Wherein the containment simulation body is used for simulating an actual containment environment; the spraying simulation body is used for storing a simulation working medium and is provided with a crevasse simulation pipe connected into the containment simulation body; the steam generating device is connected with the containment simulation body and is used for spraying steam to the containment simulation body. The spraying simulation body and the steam generation device are matched with each other, so that an energy source similar to the actual energy source is provided for simulating a large crevasse accident, and seamless connection simulation from rapid spraying to long-term spraying at the initial stage of the accident is met; and the simulation body can be sprayed in a vacant manner, and steam is sprayed to the containment simulation body only through the steam generation device so as to simulate a whole-field power-off accident. Accurate simulation of the whole process of an accident is achieved, and more real and more complete experimental data are provided for researchers.

Description

Technical Field

[0001] This application relates to the technical field of reactor safety research, and particularly to a mass-energy release system and method for simulating nuclear reactor accidents. Background Art

[0002] In the research of containment thermal-hydraulics, it is extremely crucial to simulate the mass-energy release of a large-break accident and a station blackout accident in a nuclear reactor. When a large-break accident occurs, in the early stage, a large amount of mass and energy will be rapidly released into the airspace inside the containment, and its release power is extremely high, reaching the order of ten thousand megawatts. However, in the later stage of the accident, the power will drop sharply, possibly dropping to the megawatt level or even lower, showing a huge multiple difference in power between the early and later stages. When a station blackout accident occurs, the level of mass-energy release is relatively low, and its mass-energy release curve is completely within the range of the mass-energy release curve of the large-break accident. Nevertheless, it will still have an impact on the thermal-hydraulic state of the containment.

[0003] In the prior art, the mass-energy release systems for simulating nuclear reactor accidents mostly rely on steam injection schemes. Their steam energy density is low, unable to cover the mass-energy release throughout the accident process, and it is also difficult to simulate the spraying speed, resulting in the lack of simulation in the initial stage of the accident, which is not conducive to accident verification; some use the method of storing high-energy liquid in a pressure vessel for spraying, lacking the simulation of the containment and the long-term spraying stage of the accident, as well as the corresponding connection structure and process conversion design, lacking the process conversion from the rapid spraying in the early stage of the accident to the long-term spraying and the power control process, showing differences from the actual accident process. Summary of the Invention

[0004] Based on this, a mass-energy release system and method for simulating nuclear reactor accidents are provided to alleviate the problem of inaccurate simulation of the entire accident process caused by insufficient mass-energy coverage and lack of simulation of long-term spraying during the simulation of accident mass-energy release.

[0005] An embodiment of the first aspect of this application provides a mass-energy release system for simulating nuclear reactor accidents, including:

[0006] A containment simulation body, which is used to simulate the actual containment environment;

[0007] A spraying simulation body, which is used to store simulation working medium and is provided with a break simulation pipe connected to the inside of the containment simulation body;

[0008] A steam generating device, which is connected to the containment simulation body and is used to spray steam into the containment simulation body.

[0009] In one embodiment, the mass-energy release system for simulating a nuclear reactor accident further includes a pipeline device. The pipeline device connects the steam generating device to the ejection simulation body. After the ejection of the ejection simulation body ends, the steam generating device ejects the steam into the containment simulation body through the break simulation pipe.

[0010] In one embodiment, the pipeline device includes a stop valve, a check valve, and a regulating valve. The stop valve, the check valve, and the regulating valve are all connected between the steam generating device and the ejection simulation body;

[0011] The stop valve is used to control the connection between the steam generating device and the ejection simulation body;

[0012] The check valve is used to prevent the simulated working fluid from flowing back to the steam generating device;

[0013] The regulating valve is used to adjust the steam flow rate delivered by the steam generating device to the ejection simulation body.

[0014] In one embodiment, the ejection simulation body is disposed at the bottom position inside the containment simulation body;

[0015] The steam generating device is connected to the bottom of the ejection simulation body for injecting the steam into the ejection simulation body from the bottom of the ejection simulation body.

[0016] In one embodiment, the mass-energy release system for simulating a nuclear reactor accident further includes:

[0017] A skirt support device. The skirt support device is connected to the bottom of the containment simulation body and is also connected to the bottom of the ejection simulation body. The skirt support device, the containment simulation body, and the ejection simulation body jointly form a pressure boundary.

[0018] In one embodiment, a heating device is provided at the bottom of the ejection simulation body. The heating device is used to heat the simulated working fluid inside the ejection simulation body.

[0019] In one embodiment, the heating device includes heating rods. One end of each heating rod is disposed inside the ejection simulation body, and the other end is disposed inside the skirt support device.

[0020] In one embodiment, a steam condenser is connected to the steam generating device. The steam condenser is used to consume the steam generated by the steam generating device.

[0021] In one embodiment, the steam generating device is connected to a water pump and a water tank, and the water in the water tank is supplied to the steam generating device through the water pump to adjust the steam generating device to maintain a preset liquid level.

[0022] In one embodiment, the break simulation pipe includes a spray pipe and a bursting valve provided on the spray pipe.

[0023] An embodiment of the second aspect of the present application provides a method for simulating the mass and energy release of a nuclear reactor accident, including the following steps:

[0024] Simulating a large break accident: injecting a simulated working fluid into the spray simulation body; spraying the simulated working fluid into the containment simulation body through the break simulation pipe to simulate the rapid spraying condition in the initial stage of the accident; switching to the steam generating device to spray steam into the containment simulation body for a long time to simulate the continuous spraying condition in the later stage of the accident; or

[0025] Simulating a station blackout accident: the spray simulation body is empty; only the steam generating device sprays steam into the containment simulation body, and the steam generating device adjusts the spraying power to a preset power.

[0026] In one embodiment, the injecting the simulated working fluid into the spray simulation body includes:

[0027] Injecting a working fluid into the spray simulation body and heating the working fluid to obtain the simulated working fluid at a preset temperature and a preset pressure.

[0028] In one embodiment, the heating the working fluid includes:

[0029] Heating the working fluid in the spray simulation body through a heating device.

[0030] In one embodiment, the spraying the simulated working fluid into the containment simulation body through the break simulation pipe to simulate the rapid spraying condition in the initial stage of the accident includes:

[0031] When simulating the rapid spraying condition in the initial stage of the accident, the steam generating device operates at a preset power, and the generated steam is delivered to the steam condenser.

[0032] In one embodiment, when the steam generating device operates at a preset power, the steam generating device is replenished with water through a water pump and a water tank to adjust the steam generating device to maintain a preset liquid level.

[0033] In one embodiment, the switching to the steam generating device to spray steam into the containment simulation body for a long time to simulate the continuous spraying condition in the later stage of the accident includes:

[0034] The steam generating device sprays the steam into the containment simulator through the break simulation pipe of the spraying simulator;

[0035] The switching between the initial rapid spraying condition in the initial stage of the initial accident and the continuous spraying condition in the later stage of the simulated accident is realized through a stop valve connected between the steam generating device and the spraying simulator.

[0036] According to the mass and energy release system and method for simulating nuclear reactor accidents in the embodiments of the present application, the simulated working medium is configured as high-temperature and high-pressure water consistent with the reactor state, and the simulated working medium is sprayed into the containment simulator through the spraying simulator to simulate the initial rapid spraying condition in the initial stage of a large break accident in the reactor, where the high-temperature and high-pressure water in the primary loop instantaneously releases a huge amount of energy; steam is sprayed into the containment simulator through the steam generating device to simulate the continuous spraying condition in the later stage of a large break accident in the reactor, where steam is continuously provided to the containment simulator. The spraying simulator and the steam generating device cooperate with each other to provide an energy source similar to the actual situation for simulating a large break accident, so that the mass and energy release system for simulating nuclear reactor accidents in the embodiments of the present application can meet the seamless connection simulation from the initial rapid spraying to the long-term spraying during the simulation of a large break accident; the spraying simulator can also be emptied, and only steam is sprayed into the containment simulator through the steam generating device to simulate a station blackout accident. The accurate simulation of the entire accident process is realized, providing more real and complete experimental data for researchers. Description of the Drawings

[0037] Figure 1 It is a schematic structural diagram of a mass and energy release system for simulating nuclear reactor accidents according to an embodiment of the present application.

[0038] Figure 2 It is a flowchart of a mass and energy release method for simulating nuclear reactor accidents according to an embodiment of the present application.

[0039] Figure 3 It is another flowchart of a mass and energy release method for simulating nuclear reactor accidents according to an embodiment of the present application.

[0040] Reference Signs:

[0041] 1000, containment simulator;

[0042] 2000, spraying simulator; 2100, break simulation pipe; 2110, spraying pipe; 2120, bursting valve; 2200, heating device;

[0043] 3000, steam generating device;

[0044] 4000, pipeline device; 4100, stop valve; 4200, check valve; 4300, regulating valve;

[0045] 5000, skirt support device;

[0046] 6000, steam condenser;

[0047] 7000, water pump;

[0048] 8000, water tank. Detailed implementation manners

[0049] To make the above objects, features, and advantages of the present application more obvious and understandable, the following will describe the detailed implementation manners of the present application in conjunction with the accompanying drawings. Many specific details are set forth in the following description to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0050] In the description of the present application, it should be understood that if there are terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., the orientation or positional relationship indicated by these terms is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application 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 should not be construed as a limitation of the present application.

[0051] In addition, if there are terms such as "first" and "second", these terms are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present application, if there is a term "plurality", the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0052] In the present application, unless otherwise clearly specified and limited, if there are terms such as "installation", "connection", "connection", "fixation", etc., these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0053] In this application, unless otherwise clearly specified and defined, when a first feature is described as being "on" or "under" a second feature or similar descriptions, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or simply indicates that the first feature has a lower horizontal height than the second feature.

[0054] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. If an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are only for the purpose of illustration and do not represent the only implementation.

[0055] In the field of containment thermal-hydraulic research, large-break accidents and station blackout accidents are among the accident types that must be considered. When a large-break accident occurs, a large amount of mass and energy will be rapidly released into the atmospheric space inside the containment during the early stage, and its release power is extremely large, reaching the order of ten thousand megawatts. However, in the later stage of the accident, the power will drop sharply, possibly dropping to the megawatt level or even lower, and there is a huge multiple difference in the power between the early and later stages. This huge power change has an extremely complex impact on the thermal-hydraulic characteristics inside the containment. For example, it will cause the temperature and pressure inside the containment to change rapidly, trigger strong gas convection and complex flow phenomena, affect processes such as heat transfer and mass diffusion inside the containment, and seriously threaten the integrity and stability of the containment.

[0056] When a station blackout accident occurs, the level of mass and energy release is relatively low, and its mass and energy release curve is completely contained within the mass and energy release curve of the large-break accident. Nevertheless, it will still have an impact on the thermal-hydraulic state of the containment. For example, it may cause some cooling systems and pressure regulation systems that rely on electricity to maintain normal operation to fail, indirectly affecting the thermal-hydraulic balance inside the containment. Covering the situation of the station blackout accident when studying the large-break accident can more comprehensively and systematically analyze the thermal-hydraulic characteristics of the containment under various accident conditions, providing a more sufficient theoretical basis and technical support for ensuring the safety of nuclear facilities.

[0057] The present inventor has noticed that currently, in the field of mass and energy release simulation of containment thermal-hydraulic experiments, the engineering practical applications and the solutions adopted by most inventions mainly focus on high-energy steam. However, there are inherent limitations in the energy density of steam, resulting in difficulties in completely covering the entire process of the accident in terms of the mass and energy release level during the simulation of a large-break accident, and the release rate not being able to match the changing characteristics of the entire accident process. These limitations directly lead to the lack of simulation of the initial stage of the accident, which has an adverse impact on the accident verification work.

[0058] Some inventions attempt to simulate the release process of high-energy fluids by storing high-energy liquids in a pressure vessel and then releasing them. However, due to differences in experimental purposes, there are many deficiencies in this method, including the lack of effective simulation of the containment and the long-term release stage of the accident, the lack of a reasonable design for the connection structure between the containment and the release pressure vessel, and the failure to achieve the process conversion from rapid release in the early stage of the accident to long-term release and power control.

[0059] At the present stage, the general solution is to connect pipes from outside the shell and set nozzles at corresponding positions, and to achieve the regulation of mass and energy release through flow rate, temperature, and pressure control. However, this solution does not consider the influence of the heat capacity of the pressure vessel on the released mass and energy. Therefore, at the physical phenomenon level, there are still certain differences from the accident process of the reactor prototype.

[0060] Based on the above considerations, in order to alleviate the problem of inaccurate simulation of the entire accident process caused by insufficient mass and energy coverage and the lack of long-term release simulation during the simulation of accident mass and energy release, the inventor has conducted in-depth research and designed a mass and energy release system for simulating nuclear reactor accidents. By setting a containment simulation body, a release simulation body, and a steam generation device on the mass and energy release system for simulating nuclear reactor accidents, an energy source similar to the actual situation is provided for simulating large-break accidents, so that the mass and energy release system for simulating nuclear reactor accidents in the embodiments of the present application can meet the seamless connection simulation from rapid release in the early stage of the accident to long-term release during the simulation of large-break accidents.

[0061] Refer to Figure 1 , at least one embodiment of the present application proposes a mass and energy release system for simulating nuclear reactor accidents. The mass and energy release system for simulating nuclear reactor accidents includes a containment simulation body 1000, a release simulation body 2000, and a steam generation device 3000. Among them, the containment simulation body 1000 is used to simulate the actual containment environment; the release simulation body 2000 is used to store the simulation working medium, and is provided with a break simulation pipe 2100 connected to the inside of the containment simulation body 1000; the steam generation device 3000 is connected to the containment simulation body 1000 and is used to spray steam into the containment simulation body 1000.

[0062] According to the mass-energy release system for simulating nuclear reactor accidents in the embodiments of the present application, the simulated working medium is configured as high-temperature and high-pressure water consistent with the reactor state, and the simulated working medium is sprayed into the containment simulator 1000 through the spraying simulator 2000 to simulate the rapid spraying condition at the initial stage of a large-break accident in the reactor, where the high-temperature and high-pressure water in the primary loop instantaneously releases a huge amount of energy; steam is sprayed into the containment simulator 1000 through the steam generating device 3000 to simulate the continuous spraying condition in the later stage of the reactor large-break accident, where steam is continuously provided to the containment simulator 1000. The spraying simulator 2000 and the steam generating device 3000 cooperate with each other to provide an energy source similar to the actual situation for simulating the large-break accident, so that the mass-energy release system for simulating nuclear reactor accidents in the embodiments of the present application can meet the seamless connection simulation from the rapid spraying at the initial stage of the accident to the long-term spraying when simulating the large-break accident; the spraying simulator 2000 can also be emptied, and only steam is sprayed into the containment simulator 1000 through the steam generating device 3000 to simulate the station blackout accident. By increasing the mass-energy release power and accurately simulating the spraying speed and time, the accurate simulation of the entire accident process is realized, providing more real and complete experimental data for researchers. In some embodiments, the simulated working medium is configured as high-temperature and high-pressure water.

[0063] In the embodiments of the present application, by simulating the volume of the primary loop of the reactor through the spraying simulator 2000, the experiment can be carried out on the basis of a material capacity similar to that of the primary loop, ensuring that parameters such as the total amount of matter and the energy distribution in the subsequent simulation process are similar to those of the actual reactor primary loop, providing a basis for accurately simulating the accident process. The pressure vessel structure of the reactor prototype in the prior art is extremely complex. If it is completely replicated in the experimental simulation, not only the cost is high and the manufacturing difficulty is large, but also the experimental system will be too complex to control and operate. Through reasonable design, the embodiments of the present application simplify it, reducing the construction difficulty and cost of the experimental system.

[0064] The spraying simulator 2000 stores high-temperature and high-pressure water in the same state to release energy and material flow similar to those in the actual large-break accident of the reactor during the accident simulation. The high-temperature and high-pressure water contains a huge amount of energy. When the simulated accident occurs, the rapid release of this water can reproduce the scene of a large amount of mass-energy being rapidly released in the early stage of the actual accident, making the experimental results closer to the real situation and helping researchers accurately observe and analyze various thermal-hydraulic phenomena during the accident. A break simulation pipe 2100 is arranged on the side of the spraying simulator 2000 to simulate the double-ended shear fracture of the cold leg section in the large-break accident. The break simulation pipe 2100 enables the high-temperature and high-pressure water in the spraying simulator 2000 to be sprayed in a manner and path close to the actual accident.

[0065] In some embodiments, the mass-energy release system for simulating a nuclear reactor accident further includes a pipeline device 4000. The pipeline device 4000 connects the steam generation device 3000 to the discharge simulation body 2000. After the discharge of the discharge simulation body 2000 ends, the steam generation device 3000 discharges steam into the containment simulation body 1000 through the break simulation pipe 2100.

[0066] In some embodiments, the pipeline device 4000 includes a number of pipelines, and a stop valve 4100, a check valve 4200, and a regulating valve 4300 provided on the pipelines. The stop valve 4100, the check valve 4200, and the regulating valve 4300 are all connected between the steam generation device 3000 and the discharge simulation body 2000. The stop valve 4100 is used to control the connection between the steam generation device 3000 and the discharge simulation body 2000; the check valve 4200 is used to prevent the simulated working fluid from flowing back to the steam generation device 3000; the regulating valve 4300 is used to adjust the steam flow rate delivered by the steam generation device 3000 to the discharge simulation body 2000. The stop valve 4100 mainly plays a key role in controlling the on-off of the pipeline in the system, thereby determining whether the steam generation device 3000 supplies steam to the discharge simulation body 2000. The check valve 4200 plays an important role in preventing steam from flowing back. It ensures that steam can only flow in a specified direction, that is, from the steam generation device 3000 to the discharge simulation body 2000, effectively avoiding the substances and pressure in the discharge simulation body 2000 from acting on the steam generation device 3000 in reverse. The regulating valve 4300 can adjust the steam flow rate and pressure, so as to meet the diverse requirements for mass-energy release in different experimental stages.

[0067] For controlling the mass-energy release in different stages, when simulating the rapid discharge condition in the initial stage of the accident: the stop valve 4100 is closed. At this time, only the high-temperature and high-pressure water stored in the discharge simulation body 2000 is used for discharge, so as to simulate the scene where a large amount of high-temperature and high-pressure fluid rapidly discharges from the container at the initial stage of a large break accident in the reactor. After the discharge of the discharge simulation body 2000 ends: the stop valve 4100 is opened, and the steam generation device 3000 starts to work to provide mass-energy for the subsequent long-term discharge. In this way, the whole process of the reactor accident from rapid discharge in the initial stage to long-term discharge in the later stage is completely simulated in terms of time dimension, making the simulation experiment closer to the actual accident situation.

[0068] In some embodiments, the discharge simulation body 2000 is arranged at the bottom position inside the containment simulation body 1000. The steam generation device 3000 is connected to the bottom of the discharge simulation body 2000, and steam is supplied to be injected into the discharge simulation body 2000 from the bottom of the discharge simulation body 2000. Through the above settings, the steam is connected from the bottom of the discharge simulation body 2000. Through steam heating, the simulation of the accident decay heat and the influence of the heat capacity inside the container can be more comprehensively simulated, and the discharge port is more similar to the prototype.

[0069] It can be understood that in some embodiments, the blowdown simulation body 2000 can be placed outside the containment simulation body 1000. However, setting it inside the containment simulation body 1000 can avoid technical problems such as the increase in pipeline length and resistance, and at the same time reduce the technical problem of the blowdown orifice diameter, and reduce the cost of precision machinery. The steam generation device 3000 is connected to the blowdown simulation body 2000 and blows down through the unified break simulation pipe 2100, avoiding the technical problem of matching design of multiple nozzles.

[0070] In some embodiments, the mass and energy release system for simulating a nuclear reactor accident further includes a skirt support device 5000. The skirt support device 5000 is connected to the bottom of the containment simulation body 1000 and is also connected to the bottom of the blowdown simulation body 2000. The skirt support device 5000, the containment simulation body 1000, and the blowdown simulation body 2000 together form a pressure boundary. The blowdown simulation body 2000 stores high-temperature and high-pressure water inside, which has a large weight and pressure. The skirt support device 5000 can provide stable support for the blowdown simulation body 2000, ensuring that it remains in a fixed position during the experiment and will not be displaced, tilted, or even collapsed due to its own weight or pressure fluctuations during the experiment, thus guaranteeing the stability of the entire simulation system. When simulating a reactor accident, there is a certain pressure inside both the blowdown simulation body 2000 and the containment simulation body 1000. The skirt support device 5000 is connected to the wall surface of the blowdown simulation body 2000 and the wall surface of the containment simulation body 1000, forming a closed pressure boundary. This pressure boundary can effectively prevent internal pressure leakage, maintain the stability of the pressure environment inside the system, make the pressure change during the experiment closer to the actual reactor accident situation, and at the same time ensure the safety of experimental personnel and the surrounding environment.

[0071] In some embodiments, a heating device 2200 is provided at the bottom of the blowdown simulation body 2000. The heating device 2200 is used to heat the simulated working fluid inside the blowdown simulation body 2000. Specifically, the heating device 2200 can be configured as an alternating current heating system for heating the working fluid inside the blowdown simulation body 2000 from low temperature to high temperature and high pressure. Installing an alternating current heating system at the bottom of the blowdown simulation body 2000 solves the problem of heating up the working fluid in the blowdown simulation body 2000 before the experiment, realizes the heating of the working fluid inside the blowdown simulation body 2000, and provides high-energy fluid for simulating accident blowdown.

[0072] In some embodiments, the heating device 2200 includes a heating rod. One end of the heating rod is disposed inside the blowdown simulation body 2000, and the other end is disposed inside the skirt support device 5000. Specifically, the heating rod is configured as an alternating current heating rod. The alternating current heating rod is disposed at the bottom of the blowdown simulation body 2000 and extends into the blowdown simulation body 2000, so that the heating rod can directly heat the simulated working medium inside the simulation body. Heating from the inside can make the heat transfer more efficient, improve the heating efficiency, ensure that the water in the blowdown simulation body 2000 can quickly reach and maintain the high temperature and high pressure conditions consistent with the reactor state, and ensure the accuracy of the simulation experiment. The skirt support device 5000 solves the problems of protection of the heating rod inside the containment simulation body 1000 and penetration of the containment simulation body 1000, provides a layout space for the heating rod, and enables the heating rod to be reasonably installed at the bottom of the blowdown simulation body 2000. This not only facilitates the installation and maintenance of the heating system, but also can better simulate the actual energy transfer and distribution mode of the reactor by heating from the bottom, improving the accuracy of the simulation experiment.

[0073] In some embodiments, the steam generating device 3000 is connected to a steam condenser 6000, and the steam condenser 6000 is used to consume the steam generated by the steam generating device 3000. Specifically, the steam generating device 3000 is configured as an electrically heated steam generating device 3000. With the above arrangement, the steam condenser 6000 is connected to the steam generating device 3000. The steam generating device 3000 generates steam during operation, and the steam condenser 6000 can consume this steam, that is, convert the steam into other states such as liquid water. This process realizes the recovery and treatment of steam, avoids the random discharge of steam, and ensures the reasonable recycling of substances and energy in the system. The steam condenser 6000 provides steam treatment to maintain the high-power operation of the steam generating device 3000, maintain a relatively high operating power of the steam generating device 3000 before blowdown, and achieve high-power switching.

[0074] Since the steam generating device 3000 can maintain a relatively high operating power before blowdown, when it is necessary to blow in mass and energy into the containment, that is, to switch from a low power or preparation stage to a high-power blowdown stage, it can be achieved faster. Before blowing into the containment simulation body 1000, by using the steam condenser 6000 to consume the steam, the steam generating device 3000 can maintain a relatively high operating power. Because if the steam is not processed in time, it will accumulate in the system, which may lead to too high pressure, affect the normal operation of the steam generating device 3000, and limit its power output. By consuming the steam through the condenser, the pressure in the system can be stably controlled, and the steam generating device 3000 can continuously operate at a relatively high power, ensuring a stable supply of energy and providing sufficient energy reserves for the simulation experiment.

[0075] It is understandable that, in some embodiments, the steam generated by the steam generating device 3000 can be directly discharged into the atmosphere.

[0076] In some embodiments, the steam generating device 3000 is connected to a water pump 7000 and a water tank 8000. The water in the water tank 8000 is supplied to the steam generating device 3000 through the water pump 7000 to adjust the steam generating device 3000 to maintain a preset liquid level. Connecting the water tank 8000 and the water pump 7000 to the steam generating device 3000 and setting a liquid level interlock control can solve the problem of unstable liquid level of the steam generating device 3000 and maintain the stable operation of the liquid level of the steam generating device 3000. Specifically, it can be in the steam generating device 3000.

[0077] In some embodiments, the break simulation pipe 2100 includes a spray pipe 2110 and a bursting valve 2120 provided on the spray pipe 2110. Opening the bursting valve 2120 can cause the high-energy fluid in the spray simulation body 2000 to quickly spray into the containment simulation body 1000, and the bursting valve 2120 is used to realize the start of the rapid spray of the spray simulation body 2000 during the experiment.

[0078] The mass and energy release system for simulating nuclear reactor accidents provided by the embodiments of the present application adopts high-energy liquid spraying combined with reasonable design, greatly improves the mass and energy release power, and accurately simulates the spraying speed and time; the skirt support device 5000 solves the technical problems related to alternating current heating; the electric heating steam generating device 3000 realizes the seamless connection from the rapid spray at the initial stage of the accident to the long-term spray.

[0079] Refer to Figure 2 and Figure 3 , at least one embodiment of the present application proposes a method for simulating the mass and energy release of a nuclear reactor accident. The method for simulating the mass and energy release of a nuclear reactor accident includes the following steps:

[0080] Simulate a large break accident:

[0081] Step S110: Inject a simulated working fluid into the spray simulation body 2000;

[0082] Step S120: Spray the simulated working fluid into the containment simulation body 1000 through the break simulation pipe 2100 to simulate the rapid spray condition at the initial stage of the accident;

[0083] Step S130: Switch to the steam generating device 3000 to spray steam into the containment simulation body 1000 for a long time to simulate the continuous spray condition in the later stage of the accident; or

[0084] Simulate a station blackout accident:

[0085] Step S210: The spray simulation body 2000 is empty;

[0086] Step S220: Only spray steam into the containment simulator 1000 through the steam generating device 3000, and the steam generating device 3000 adjusts the spraying power to a preset power.

[0087] According to the mass-energy release method for simulating nuclear reactor accidents in the embodiments of the present application, large break accidents and station blackout accidents can be simulated according to research requirements, achieving accurate simulation of the entire accident process, and providing more real and complete experimental data for researchers.

[0088] In some embodiments, step S110: Injecting the simulated working fluid into the spraying simulator 2000 includes: injecting the working fluid into the spraying simulator 2000 and heating the working fluid to obtain the simulated working fluid at a preset temperature and preset pressure.

[0089] In some embodiments, filling the spraying simulator 2000 with water to a preset weight can simulate the actual inventory of water in the primary loop of the reactor. By precisely controlling the water injection volume, it can ensure that the total amount of substances released by the simulator in subsequent experiments is similar to that in the large break accident of the primary loop of the reactor, making the experimental results more valuable for reference. For example, if the water injection volume is too large, the released mass-energy will exceed the actual accident level; if it is too small, the true intensity of the accident cannot be simulated.

[0090] In some embodiments, heating the working fluid includes: heating the working fluid in the spraying simulator 2000 through the heating device 2200.

[0091] Using the heating device 2200 to heat the water in the spraying simulator 2000 to reach the required temperature and pressure. Different reactor operating conditions correspond to different temperature and pressure parameters. Precisely controlling the temperature and pressure after heating in the experiment can more accurately simulate the mass-energy release process under specific accident scenarios, facilitating researchers to observe and analyze relevant thermal-hydraulic phenomena.

[0092] In some embodiments, step S120: Spraying the simulated working fluid into the containment simulator 1000 through the break simulation pipe 2100, and simulating the rapid spraying condition in the initial stage of the accident includes: When simulating the rapid spraying condition in the initial stage of the accident, the steam generating device 3000 operates at a preset power, and the generated steam is delivered to the steam condenser 6000. Specifically, the steam generating device 3000 is configured as an electric heating steam generating device 3000, and the preset power is a relatively high power.

[0093] The steam generation device 3000 can heat water to convert it into steam. During the experimental preparation stage, the generated steam is discharged through a pipeline into a condenser for condensation. This can maintain the stable operation of the system and prevent excessive accumulation of steam in the system, which may lead to too high pressure. The condensed water can be recycled and reused, meeting the principles of economy and sustainability of the experiment. At the same time, the electric power of the steam generation device 3000 is operated under a relatively high power condition to enable the electric heating steam generation device 3000 to quickly generate sufficient steam, ensuring that there is an adequate steam reserve in the device when needed in the experiment and it can be put into use at any time.

[0094] In some embodiments, when the steam generation device 3000 operates at a preset power, the steam generation device 3000 is replenished with water through a water pump 7000 and a water tank 8000 to adjust the steam generation device 3000 to maintain a preset liquid level. Specifically, a liquid level sensor is provided in the steam generation device 3000. When the liquid level in the electric heating steam generation device 3000 drops due to steam generation, the liquid level sensor will detect this change and transmit a signal to the water pump 7000. The water pump 7000 starts to supply water to the electric heating steam generation device 3000 to maintain its liquid level stable. On the contrary, if the liquid level is too high, the water pump 7000 will reduce or stop supplying water. Maintaining a stable liquid level is very important for the normal operation of the electric heating steam generation device 3000. Too low a liquid level may cause the heating element to dry burn and damage the equipment. Too high a liquid level may affect the steam generation efficiency and quality, and thus affect the simulation effect of the entire experiment. Through this liquid level interlock operation mechanism, it is ensured that the electric heating steam generation device 3000 can stably generate steam throughout the experimental preparation stage and the subsequent experimental process.

[0095] In some embodiments, in step S130, switching to the steam generation device 3000 to spray steam into the containment simulator 1000 for a long time, the simulation of the continuous spray condition in the later stage of the accident includes:

[0096] The steam generation device 3000 sprays steam into the containment simulator 1000 through the break simulation pipe 2100 of the spray simulator 2000;

[0097] The switching between the initial rapid spray condition in the initial stage of the accident and the continuous spray condition in the later stage of the simulated accident is achieved through a stop valve 4100 connected between the steam generation device 3000 and the spray simulator 2000.

[0098] According to the energy-mass release method for simulating nuclear reactor accidents provided by the embodiments of the present application, during the large-break accident simulation experiment: In the experimental preparation stage, an appropriate amount of water is injected into the spray simulation body 2000 according to experimental requirements, and the heating device 2200 is started to heat the water to the set temperature and pressure. The steam generation device 3000 starts to work, and the generated steam is discharged into the condensation heat exchanger for condensation. At the same time, the electric power is adjusted and maintained at a relatively high level, and the water pump 7000 replenishes water according to the liquid level change of the steam generation device 3000;

[0099] In the experimental implementation stage, the bursting valve 2120 of the spray pipe 2110 on the spray simulation body 2000 is opened, and the high-temperature and high-pressure water is sprayed into the containment simulation body 1000 from the break simulation pipe 2100 to simulate the rapid spraying process of the simulation container. When the spraying of the spray simulation body 2000 is completed, the stop valve 4100 is opened to switch the steam flow direction, and the steam generated by the steam generation device 3000 is injected from the bottom of the spray simulation body 2000 to simulate the long-term spraying process.

[0100] During the station blackout accident simulation experiment: In the experimental preparation stage, the spray simulation body 2000 remains in an empty state. The steam generation device 3000 is started and adjusted according to the power requirements set by the experiment, and the generated steam is directly sprayed into the containment simulation body 1000 to simulate the energy-mass release process in the station blackout accident.

[0101] During a station blackout accident, the reactor cooling system and related power equipment are shut down, and the water in the primary circuit may not be able to circulate normally due to the loss of power, which is different from the situation where a large amount of high-temperature and high-pressure water in the primary circuit is rapidly released during a large-break accident. If the spray simulation body 2000 is pre-filled with water, when simulating a station blackout accident, the actual distribution of water in the system and the energy release state cannot be accurately presented. Arranging it as a hollow container is closer to the possible state of the reactor primary circuit during a station blackout accident, which can avoid simulation deviations caused by water injection and ensure the reliability of the simulation results. The energy-mass release level during a station blackout accident is low, but there is still an energy release process. The electric heating steam generation device 3000 switches and adjusts the power as needed to simulate the slow energy release inside the reactor. By adjusting the power of this device, the steam generation amount and energy can be controlled, and then the thermohydraulic changes in the containment under different degrees of station blackout accidents can be simulated. For example, at the initial stage of the accident, a small amount of steam is generated with low power to simulate the slow energy release. As the accident develops, the power is adjusted according to research needs to simulate the dynamic change of energy release, providing an effective means for researchers to analyze the impact of station blackout accidents on the thermohydraulic characteristics of the containment.

[0102] The simulation reactor accident energy-mass release system and method according to the embodiments of the present application have the following beneficial effects:

[0103] By adopting high-energy liquid ejection and reasonably designing the structure of the ejection pipe 2110 line and the pre-installed amount of the ejection simulation body 2000, the mass-energy release power can be significantly improved, and the speed and time of the container ejection can be accurately simulated. Through numerical calculation, this method can achieve an effect similar to that of the prototype accident.

[0104] A skirt support device 5000 is provided at the bottom of the ejection simulation body 2000. With a pressure-bearing design, it is integrally designed with the ejection simulation body 2000 and the containment simulation body 1000. It not only plays the role of the pressure boundary but also can lead out alternating current heating from the bottom, solving technical problems such as the protection of alternating current heating inside the shell and the penetration of the shell.

[0105] The electric heating steam generation device 3000 can be in a standby state for a long time and can be switched at any time when conditions are met. Moreover, due to being in a long-term standby state, the electric heating power can be maintained at a relatively high level, enabling the system to achieve seamless simulation from the rapid ejection of the container in the initial stage of the accident to the long-term ejection.

[0106] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0107] The above-described embodiments only represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A mass-energy release system for simulating a nuclear reactor accident, characterized in that: include: A containment simulation body, wherein the containment simulation body is used to simulate an actual containment environment; A spray simulation body, the spray simulation body is used to store simulated working fluid and is provided with a rupture simulation pipe connected to the containment simulation body; A steam generating device is connected to the containment shell simulation body and is used for spraying steam into the containment shell simulation body.

2. The mass-energy release system for simulating a nuclear reactor accident according to claim 1, characterized in that: The mass-energy release system for simulating nuclear reactor accidents also includes a pipeline device, which connects the steam generating device with the spraying simulation body. After the spraying of the spraying simulation body is completed, the steam generating device sprays the steam to the containment simulation body through the rupture simulation pipe.

3. The mass-energy release system for simulating a nuclear reactor accident according to claim 2, characterized in that: The pipeline device comprises a stop valve, a check valve and a regulating valve, and the stop valve, the check valve and the regulating valve are all connected between the steam generating device and the spray simulation body; The stop valve is used to control the communication between the steam generating device and the spray simulation body; The check valve is used to prevent the simulated working fluid from flowing back to the steam generating device; The regulating valve is used to adjust the steam flow rate delivered by the steam generating device to the spray simulation body.

4. The mass-energy release system for simulating a nuclear reactor accident according to claim 2, characterized in that: The spray simulation body is arranged at the bottom position in the containment simulation body; The steam generating device is connected to the bottom of the spray simulation body, so that the steam is injected into the spray simulation body from the bottom of the spray simulation body.

5. The mass-energy release system for simulating a nuclear reactor accident according to claim 4, characterized in that: The mass-energy release system for simulating a nuclear reactor accident also includes: A skirt support device is connected to the bottom of the containment simulation body and to the bottom of the blowdown simulation body. The skirt support device, the containment simulation body and the blowdown simulation body together form a pressure boundary.

6. The mass-energy release system for simulating a nuclear reactor accident according to claim 5, characterized in that: A heating device is arranged at the bottom of the spray simulation body, and the heating device is used to heat the simulated working medium in the spray simulation body.

7. The mass-energy release system for simulating a nuclear reactor accident according to claim 6, characterized in that: The heating device comprises a heating rod, one end of which is arranged inside the spray simulation body, and the other end of which is arranged inside the skirt support device.

8. The mass-energy release system for simulating a nuclear reactor accident according to any one of claims 1 to 7, characterized in that: The steam generating device is connected to a steam condenser, and the steam condenser is used to absorb the steam generated by the steam generating device.

9. The mass-energy release system for simulating a nuclear reactor accident according to any one of claims 1 to 7, characterized in that: The steam generating device is connected to a water pump and a water tank, and the water in the water tank is supplied to the steam generating device through the water pump, so as to adjust the steam generating device to maintain a preset liquid level.

10. The mass-energy release system for simulating a nuclear reactor accident according to any one of claims 1 to 7, characterized in that: The breach simulation pipe comprises a blowdown pipe and a bursting valve arranged on the blowdown pipe.

11. A method for simulating a nuclear reactor accident in terms of mass and energy release, characterized in that: The steps include: Simulate a large breach accident: inject simulated working fluid into the simulated blowdown body; spray the simulated working fluid into the simulated containment body through the breach simulation pipe to simulate the rapid blowdown condition in the early stage of the accident; switch to the steam generation device to spray steam into the simulated containment body for a long time to simulate the continuous blowdown condition in the late stage of the accident; or Simulating a full-site power outage accident: the spray simulation body is empty; steam is sprayed into the containment simulation body only through the steam generating device, and the steam generating device adjusts the spraying power to a preset power.

12. The mass-energy release method for simulating a nuclear reactor accident according to claim 11, characterized in that: The injecting of the simulated working fluid into the spraying simulation body comprises: A working fluid is injected into the spray simulation body, and the working fluid is heated to obtain the simulated working fluid reaching a preset temperature and a preset pressure.

13. The mass-energy release method for simulating a nuclear reactor accident according to claim 12, characterized in that: The heating of the working medium comprises: The working fluid in the spray simulation body is heated by a heating device.

14. The mass-energy release method for simulating a nuclear reactor accident according to claim 11, characterized in that: The simulated working fluid is sprayed into the simulated containment body through the breach simulated pipe to simulate the rapid spraying condition at the initial stage of the accident, including: When simulating the rapid release condition at the initial stage of an accident, the steam generating device maintains operation at a preset power, and the generated steam is delivered to the steam condenser.

15. The mass-energy release method for simulating a nuclear reactor accident according to claim 14, characterized in that: When the steam generating device maintains the preset power operation, water is added to the steam generating device through a water pump and a water tank to adjust the steam generating device to maintain the preset liquid level.

16. The mass-energy release method for simulating a nuclear reactor accident according to claim 11, characterized in that: The switching to the steam generating device to spray steam into the simulated containment shell for a long time to simulate the continuous spraying condition in the late stage of the accident includes: The steam generating device sprays the steam toward the containment simulation body through the breach simulation pipe of the spray simulation body; The switching between the rapid spraying condition in the early stage of the initial accident and the continuous spraying condition in the late stage of the simulated accident is achieved by connecting the stop valve between the steam generating device and the spraying simulation body.

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