Cooling water tank oscillation analysis system and method for nuclear power plant

Abstract

The invention discloses a cooling water tank oscillation analysis system and method for a nuclear power plant, and relates to the technical field of nuclear industry safety, the cooling water tank oscillation analysis system comprises a pressure vessel used for simulating a voltage stabilizer and a closed cooling water tank, a bubbler is arranged in the cooling water tank, the pressure vessel is connected to the bubbler through a gas inlet pipeline, and pressure gas is sprayed into the cooling water tank through the bubbler. The testing device is used for providing testing conditions of different pressures and different injection flows for the cooling water tank; an in-tank component simulation device and a plurality of dynamic pressure sensors are arranged in the cooling water tank, and the in-tank component simulation device is of a frame-shaped structure and is used for supporting the internal structure of the water tank; and the plurality of dynamic pressure sensors are symmetrically arranged on the inner walls of the cooling water tank and the in-tank component simulation device in an enveloping manner, and are used for monitoring and acquiring dynamic pressure load data in the cooling water tank under different test working conditions. The device can simulate the actual structural characteristics of the water tank of the nuclear power plant, and achieves the impact analysis and research of the oscillation load of the water tank under multiple working conditions.

Description

Technical Field

[0001] The invention relates to the field of nuclear industry safety technology, and in particular to a cooling water tank oscillation analysis system and method for a nuclear power plant. Background Art

[0003] The passive core cooling system is an important part of the passive safety system of advanced pressurized water reactors. It uses the passive design concept to safely inject and remove the core heat, ensure the integrity of the reactor, and ultimately prevent the release of radioactive substances to the environment. Therefore, in order to actually eliminate the possibility of a large amount of radioactive material release from the design, the function of the passive core cooling system must be guaranteed under accidents.

[0004] Under normal design, in the case of LOCA (Loss of Coolant Accident) in a nuclear power plant, a large amount of coolant in the primary circuit will be lost from the breach, resulting in the inability to remove the core heat in time. After the high-pressure injection reaches a certain level, the automatic depressurization system (ADS) will be triggered to open, completing the pressure reduction of the primary circuit, and realizing the subsequent medium and low pressure injection to remove the core heat. When the ADS system is turned on, a large amount of high-pressure steam will be injected into the refueling water tank (IRWST) in the containment through the bubbler. In this process, a large hydraulic load will be generated on the water tank, posing a great challenge to the integrity of the water tank. In other words, in order to ensure the safety and effectiveness of the passive core cooling function of nuclear power under accidents, it is necessary to ensure that the load-bearing performance design of the water tank meets safety requirements.

[0005] However, for the current new advanced passive reactors, the structural parameters of the water tank and the ADS system spray parameters have changed compared with those of boiling water reactors and traditional pressurized water reactors. The existing experimental conclusions may have large deviations, especially for the research on the influence of different pressure parameters, different injection flow rates, different bubbler models, different bubbler immersion depths, different bubbler positions, different structural forms of internal components in the tank, etc. on the spray load. There are great deficiencies, which seriously restrict the load-bearing design of the water tank. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention proposes a cooling water tank oscillation analysis system and method for a nuclear power plant. By designing a cooling water tank with a closed structure, an overpressure exhaust and negative pressure air intake device is arranged on the upper part of the cooling water tank to simulate the actual water tank structural characteristics of the nuclear power plant; on this basis, by designing a multi-stage parallel air intake valve, different air intake valves are opened according to the changes in the pressure parameters in the pressure vessel, and the influence of the water tank oscillation load under different pressures and different injection flow rates is studied, so as to clarify the influence of different parameters on the water tank oscillation load, greatly simplify the system design, and improve the safety, reliability and economy of the operation of advanced passive reactors.

[0007] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions:

[0008] A first aspect of the present invention provides a cooling water tank oscillation analysis system for a nuclear power plant.

[0009] A cooling water tank oscillation analysis system for a nuclear power plant, comprising a pressure vessel for simulating a pressurizer, and a closed cooling water tank;

[0010] A bubbler is provided in the cooling water tank, and the pressure vessel is connected to the bubbler through an air inlet pipeline, and the pressure gas is sprayed into the cooling water tank through the bubbler, so as to provide the cooling water tank with test conditions of different pressures and different spray flow rates;

[0011] The cooling water tank is provided with an internal component simulation device and multiple dynamic pressure sensors. The internal component simulation device is a frame-type structure for supporting the internal structure of the water tank; the multiple dynamic pressure sensors are symmetrically arranged on the inner walls of the cooling water tank and the internal component simulation device, and are used to monitor and obtain the dynamic pressure load data inside the cooling water tank under different test conditions.

[0012] In a further technical solution, the pressure vessel and the cooling water tank are both connected to a water supply module through a pipeline, and the water supply module includes a water reservoir;

[0013] The water reservoir is connected to the water replenishment pump through a pipeline, and then connected to the pressure vessel and the cooling water tank respectively through the water replenishment pipeline, and a water replenishment valve is provided on the water replenishment pipeline; the water replenishment valve and the water replenishment pump are electrically connected to an external control module, and the control module is used to control the opening and closing of the water replenishment valve and the water replenishment pump, so as to control the amount of water in the pressure vessel and the cooling water tank.

[0014] According to a further technical solution, the pressure vessel and the cooling water tank are both connected to a drainage module through pipelines, and the drainage module includes a drainage tank;

[0015] The drainage pool is connected to the pressure vessel and the cooling water tank respectively through drainage pipelines, and the drainage pipelines are provided with drainage valves; the drainage valves are electrically connected to an external control module, and the control module is used to control the opening and closing of the drainage valves, thereby controlling the amount of water in the pressure vessel and the cooling water tank.

[0016] According to a further technical solution, the cooling water tank is also provided with an overpressure exhaust device and a negative pressure air intake device, a liquid level measuring device, a retractable support device and a sliding track for automatically controlling and maintaining the pressure in the water tank; wherein the overpressure exhaust device and the negative pressure air intake device are arranged at the top position in the cooling water tank and are arranged outside the internal component simulation device; the bubbler, the retractable support device and the sliding track are all arranged inside the internal component simulation device;

[0017] The sliding track is fixedly installed on the bottom surface of the cooling water tank, and the bottom of the retractable support device is arranged in the sliding track to realize horizontal movement along the sliding track; one end of the bubbler is connected to the air inlet pipeline through a flange, and the other end of the bubbler is connected to the retractable support device; the bubbler is replaceable and is used to provide test conditions of different bubbler models for the cooling water tank;

[0018] By adjusting the vertical and horizontal positions of the air intake pipeline and the retractable support device, test conditions with different bubbler positions are provided for the cooling water tank, including: adjusting the vertical position of the bubbler in the cooling water tank by adjusting the vertical length of the air intake pipeline and the retractable support device; and adjusting the horizontal position of the bubbler in the cooling water tank by adjusting the horizontal position of the air intake pipeline and the retractable support device along the sliding track.

[0019] According to a further technical solution, a symmetrically arranged visualization window is provided on the shell of the cooling water tank, and a light source and a high-speed camera are provided at the visualization window for observing the spraying condition of the bubbler in the cooling water tank.

[0020] According to a further technical solution, the retractable support device comprises a retractable support fixing frame and a shock absorber;

[0021] One end of the retractable support fixing frame is connected to the bubbler, and the other end is arranged in the sliding track; the shock absorber is arranged on the retractable support fixing frame to absorb vibration energy.

[0022] According to a further technical solution, one end of the internal component simulation device is fixed to the bottom surface of the water tank through a base, and the other end is in contact with the top of the water tank and supports the structural items on the top of the water tank;

[0023] The internal component simulation device is composed of a plurality of modular simulation structures connected by bolts, each modular simulation structure is a rectangular frame structure of the same length, with openings on the top and bottom surfaces, and a plurality of replaceable guide vanes evenly arranged on the sides, for providing test conditions of different internal component structures for the cooling water tank; the guide vanes are in the form of any one of spiral, strip, and louver types.

[0024] In a further technical solution, the air intake pipeline is provided with a multi-stage parallel air intake valve and flow, pressure and temperature measuring devices in sequence; the pressure vessel is provided with a pressure, temperature and liquid level measuring device, and a heating and heat preservation device is provided on the outer wall of the bottom thereof; the heating and heat preservation device is used to heat the water in the pressure vessel to the set temperature and pressure test requirements;

[0025] Among them, the multi-stage parallel intake valve and the heating and heat preservation device are electrically connected to the external control module, and all sensors and measuring devices are electrically connected to the external data acquisition module.

[0026] A second aspect of the present invention provides a cooling water tank oscillation analysis method for a nuclear power plant.

[0027] A method for analyzing the vibration of a cooling water tank for a nuclear power plant is implemented based on a system for analyzing the vibration of a cooling water tank for a nuclear power plant provided in the first aspect, comprising:

[0028] Control the temperature and injection pressure in the pressure vessel to meet the experimental requirements;

[0029] According to the multi-operating condition experimental requirements of different injection flow rates under different injection pressures, the opening of different multi-stage parallel-connected intake valves on the intake pipeline is controlled, and the high-temperature and high-pressure water vapor inside the pressure vessel enters the bubbler through the flow, pressure, and temperature measuring devices in turn, and is sprayed into the cooling water tank through the bubbler;

[0030] During the injection process accompanied by impact-condensation-oscillation, the dynamic pressure load data inside the cooling water tank is monitored and obtained in real time;

[0031] Based on the preset operating conditions experimental requirements and the data obtained from monitoring, the cooling water tank oscillation analysis is carried out.

[0032] Further technical solutions, in order to meet the requirements of multi-condition experiments, also include:

[0033] Replace bubblers of different models;

[0034] Replace different forms of box internal component simulation devices;

[0035] Adjusting the position of the bubbler in the cooling water tank includes: adjusting the length of the air intake pipeline and the retractable support device in the vertical direction to adjust the vertical position of the bubbler in the cooling water tank; and adjusting the position of the air intake pipeline and the retractable support device along the sliding track in the horizontal direction to adjust the horizontal position of the bubbler in the cooling water tank.

[0036] One or more of the above technical solutions have the following beneficial effects:

[0037] 1. Compared with the prior art, the present invention combines the spray parameter characteristics of the ADS system in the case of an accident in a passive nuclear power plant, and proposes a cooling water tank oscillation analysis system and method for a nuclear power plant. By designing a cooling water tank with a closed structure, an overpressure exhaust device and a negative pressure air intake device are arranged on the upper part of the cooling water tank, so as to simulate the actual water tank structural characteristics of the nuclear power plant; on this basis, by designing a multi-stage parallel air intake valve, different air intake valves are opened according to the change of pressure parameters in the pressure vessel, so as to realize the influence study of the water tank oscillation load under different pressures, different injection flow rates and multiple working conditions, and greatly simplify the system design; the present invention can simulate the oscillation load generated by the water tank caused by the spraying of the ADS system of the passive pressurized water reactor in the case of an accident, so as to analyze and study the oscillation characteristics of the water tank in the advanced passive containment.

[0038] 2. In the present invention, by changing the initial pressure of the pressure vessel, the number of openings of the air inlet valve under different pressures, the bubbler model, the bubbler position (including the immersion depth), the structural form of the components inside the tank and other parameters, the influence of the above factors on the water tank shock load can be studied, the key parameters and key influencing factors can be found, the action relationship and influencing law between the above different parameter variables and the water tank shock load can be clarified, and a water tank shock parameter database caused by ADS blowdown in passive nuclear power plants can be formed, which can provide a technical basis for the subsequent design and improvement of the ADS blowdown system and cooling water tank structure of advanced passive nuclear power plants, reduce the difficulty of design and evaluation of the ADS blowdown system and cooling water tank structure of advanced active nuclear power plants, and thereby improve the operating safety, reliability and economy of advanced passive reactors. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0040] Figure 1 This is a connection diagram of a cooling water tank oscillation analysis system for a nuclear power plant according to an embodiment of the present invention;

[0041] Figure 2 A front view of the arrangement of multiple dynamic pressure sensors in the system according to an embodiment of the present invention;

[0042] Figure 3A top view of the arrangement of multiple dynamic pressure sensors in the system according to an embodiment of the present invention;

[0043] Figure 4 for Figure 2 A schematic cross-sectional view of the arrangement of multiple dynamic pressure sensors at AA in the front view shown;

[0044] Figure 5 It is a front view of a single modular simulation structure of the box internal component simulation device in the system according to the embodiment of the present invention;

[0045] Figure 6 It is a top view of a single modular simulation structure of the box internal component simulation device in the system described in an embodiment of the present invention.

[0046] Among them, 1. pressure vessel; 2. cooling water tank; 3. water reservoir; 4. drainage tank; 5. water supply pump; 6. heating and insulation device; 7. overpressure exhaust device; 8. negative pressure air intake device; 9. bubbler; 10. retractable support device; 11. box internal component simulation device; 12. flow measurement device; 13. pressure measurement device; 14. temperature measurement device; 15. liquid level measurement device; 16. dynamic pressure sensor; 17. visualization window; 18. light source; 19. high-speed camera; 20. water supply valve; 21. intake valve; 22. drain valve; 23. water supply pipeline; 24. intake pipeline; 25. drainage pipeline; 26. control module; 27. measurement module; 28. data acquisition module; 29. ​​sliding track; 30. guide vane. DETAILED DESCRIPTION

[0047] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0048] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0049] Embodiment 1

[0050] In view of the deficiencies in the prior art, this embodiment combines the spray parameter characteristics of the ADS system in the event of an accident in a passive nuclear power plant, and proposes a cooling water tank oscillation analysis system for a nuclear power plant. In the system, the cooling water tank is designed to be a closed structure, and an overpressure exhaust device and a negative pressure air intake device are provided on the upper part of the cooling water tank, which simulates the actual water tank structural characteristics of the power plant; at the same time, the cooling water tank is connected to the pressure vessel through an air intake pipeline, and the air intake valves on the air intake pipeline are arranged in parallel in multiple stages. Different air intake valves can be opened according to the changes in the pressure parameters in the pressure vessel, so as to realize the influence study of the water tank oscillation load under different pressures, different injection flow rates and multiple working conditions.

[0051] The cooling water tank oscillation analysis system for a nuclear power plant proposed in this embodiment includes a pressure vessel for simulating a pressurizer, a closed cooling water tank, a water supply module, a drainage module, a control module, a measurement module, etc. Based on this system design, the water tank oscillation load generated under experimental conditions such as different injection pressures, different injection flow rates, different bubbler models, different bubbler immersion depths, different bubbler positions, and different tank internal component structures can be studied to obtain the effect relationship of the above parameters on the water tank oscillation load, and form a oscillation load parameter database generated by the ADS system spraying, so as to provide a technical basis for the subsequent design and improvement of the ADS spraying system and IRWST water tank structure of advanced passive nuclear power plants, reduce the difficulty of design and evaluation of the ADS spraying system and IRWST water tank structure of advanced active nuclear power plants, and improve the safety, reliability and economy of system design.

[0052] Specifically, Figure 1 As shown, the cooling water tank oscillation analysis system for a nuclear power plant proposed in this embodiment includes a pressure vessel 1 for simulating a pressurizer and a sealed cooling water tank 2.

[0053] like Figure 1 As shown, the pressure vessel 1 and the cooling water tank 2 are both connected to the water supply module through pipelines, and the water supply module includes a water reservoir 3 (also called a water storage tank), which is connected to the water supply pump 5 through a pipeline, and then connected to the pressure vessel 1 and the cooling water tank 2 through a water supply pipeline 23, and a water supply valve 20 is provided on the water supply pipeline 23. The water supply valve 20 and the water supply pump 5 are both electrically connected to an external control module 26, and the control module 26 is used to control the opening and closing of the water supply valve and the water supply pump, so as to control the amount of water in the pressure vessel and the cooling water tank.

[0054] like Figure 1As shown, the pressure vessel 1 and the cooling water tank 2 are connected to the drainage module through pipelines, and the drainage module includes a drainage pool 4, which is respectively connected to the pressure vessel 1 and the cooling water tank 2 through a drainage pipeline 25, and a drainage valve 22 is provided on the drainage pipeline 25. The drainage valve 22 is electrically connected to an external control module 26, and the control module 26 is used to control the opening and closing of the drainage valve, thereby controlling the amount of water in the pressure vessel and the cooling water tank.

[0055] like Figure 1 As shown, the cooling water tank 2 is provided with an overpressure exhaust device 7 and a negative pressure air intake device 8. These two devices are used to automatically control and maintain the pressure in the water tank, so as to ensure that the pressure in the water tank is within the required range, prevent the water tank from being damaged due to overpressure or negative pressure during the experiment, and ensure the integrity of the cooling water tank. Specifically, an overpressure exhaust device 7 is provided on the upper part of the cooling water tank. When the pressure in the water tank exceeds the preset rated value of the overpressure exhaust device 7, the overpressure exhaust device 7 automatically opens to complete the pressure reduction of the water tank, ensuring the integrity of the water tank during the experiment; a negative pressure air intake device 8 is provided on the upper part of the water tank. After the spraying test is completed, the pressure in the water tank will decrease with the condensation of water vapor and the decrease in the temperature in the water tank. When the pressure in the water tank decreases to the preset rated value of the negative pressure air intake device 8, the negative pressure air intake device 8 automatically opens to complete the air intake of the water tank, ensuring that the water tank is not damaged by negative pressure.

[0056] Furthermore, the cooling water tank 2 is provided with a plurality of dynamic pressure sensors 16, a liquid level measuring device 15, a tank internal component simulation device 11, and a bubbler 9, wherein the tank internal component simulation device 11 is a frame-shaped structure for supporting the internal structure of the water tank, such as Figure 2 , Figure 3 and Figure 4 As shown, multiple dynamic pressure sensors 16 are symmetrically arranged on the inner wall of the cooling water tank and the simulation device of the internal components of the tank, which are used to detect and obtain the dynamic pressure load data of the water inside the cooling water tank under different test conditions during the experiment. Through the symmetrical arrangement of the dynamic pressure sensors, all-round measurement of the load source items from near to far in the water tank and from near to far in the water tank wall is achieved. At the same time, the symmetrical arrangement feature can also facilitate the comparison between measurement points during the later data analysis, which is convenient for data analysis. Based on the above settings, the dynamic pressure load data inside the cooling water tank under different test conditions are monitored and obtained for subsequent cooling water tank vibration analysis and research.

[0057] On the basis of the above, the pressure vessel 1 is connected to the bubbler 9 in the cooling water tank 2 through the bubbler 9, and the pressurized gas is sprayed into the cooling water tank 2 through the bubbler 9, so as to provide the cooling water tank with test conditions of different pressures and different injection flow rates; the air intake pipeline 24 is sequentially provided with a multi-stage parallel air intake valve 21 and a flow measuring device 12, a pressure measuring device 13, and a temperature measuring device 14; wherein the multi-stage parallel air intake valve 21 is electrically connected to an external control module 26, and all sensors and measuring devices are electrically connected to an external data acquisition module 28.

[0058] In addition, the pressure vessel 1 is also provided with pressure, temperature, and liquid level measuring devices. All measuring devices are used as measuring modules 27 and are electrically connected to the external data acquisition module 28. A heating and heat preservation device 6 is provided on the outer wall of the bottom of the pressure vessel 1. The heating and heat preservation device 6 is used to heat the water in the pressure vessel to the set temperature and pressure test requirements. In this embodiment, the heating and heat preservation device is an electric heating device, which is electrically connected to the external control module. Its power can be set according to the experimental requirements to achieve the heating and heat preservation function of the pressure vessel. As another embodiment, the heating of the pressure vessel is not limited to the above-mentioned heating method proposed in this embodiment, and the existing heating module can also be arranged inside the pressure vessel to achieve the heating of the pressure vessel.

[0059] In this embodiment, the control module and the data acquisition module are both implemented using existing hardware structures, such as existing controllers and memories, computers, etc., to facilitate subsequent experimental control and data processing, which will not be repeated here; in addition, the intake valve on the intake pipeline is set in three levels, that is, three-stage parallel intake valves are set, so that different intake valves can be opened according to the changes in pressure parameters in the pressure vessel and experimental requirements, thereby realizing the influence of water tank shock load under different pressures, different injection flow rates and multiple working conditions.

[0060] As another implementation manner, in this embodiment, high-precision sensors, measuring instruments, etc. are used as measuring devices. For example, the above-mentioned flow measuring device, pressure measuring device, temperature measuring device, and liquid level measuring device respectively use high-precision flow measuring instruments, high-precision pressure sensors, high-precision temperature sensors, and high-precision liquid level sensors. The various sensors and measuring devices used in this embodiment (including liquid level measuring devices, pressure measuring devices, temperature measuring devices, etc. arranged in the pressure vessel) are used as measuring modules. The measuring module is connected to the pressure vessel and the cooling water tank through cables to receive temperature, pressure, load and other data in each container and the water tank to facilitate subsequent data analysis and processing.

[0061] The cooling water tank 2 is also provided with a retractable support device 10 and a sliding track 29, and the bubbler 9, the retractable support device 10 and the sliding track 29 are all arranged inside the internal component simulation device 11; in addition, the overpressure exhaust device 7 and the negative pressure air intake device 8 are arranged at the top position in the cooling water tank 2, and are arranged outside the internal component simulation device 11. Furthermore, the bubbler 9 is used to simulate exhaust, and one end of the bubbler 9 is connected to the air intake pipeline 24 through a flange, so as to realize the model replacement and position change of the bubbler, and then realize the influence of different bubbler models, positions and immersion depths on the shock load under the test conditions; the other end of the bubbler 9 is connected to the retractable support device 10, and the sliding track 29 is fixedly installed on the bottom surface of the cooling water tank 2, and the bottom of the retractable support device 10 is arranged in the sliding track to realize horizontal movement along the sliding track. Based on the above design, by adjusting the positions of the air intake pipeline and the retractable support device in the vertical and horizontal directions, test conditions with different bubbler positions can be provided for the cooling water tank, namely: by adjusting the length of the air intake pipeline and the retractable support device in the vertical direction, the vertical position of the bubbler in the cooling water tank is adjusted; by adjusting the position of the air intake pipeline and the retractable support device in the horizontal direction along the sliding track, the horizontal position of the bubbler in the cooling water tank is adjusted.

[0062] Furthermore, the retractable support device 10 includes a retractable support fixing frame and a shock absorber, wherein one end of the retractable support fixing frame is connected to the bubbler, and the other end is arranged in the sliding track; the shock absorber is arranged on the retractable support fixing frame to absorb vibration energy to avoid shaking of the retractable support fixing frame and ensure the stability of the bubbler during the operation of the experimental device.

[0063] As another implementation, the support of the bubbler in the cooling water tank is not limited to the above-mentioned support method in this embodiment, and other existing support structures that can support, fix and reduce shock may also be used.

[0064] One end of the above-mentioned tank internal component simulation device 11 is fixed to the bottom surface of the water tank through a base, and the other end contacts the top of the water tank and supports the top structural items of the water tank. Figure 5 and Figure 6 As shown, the internal component simulation device is composed of a plurality of modular simulation structures connected by bolts. Each modular simulation structure is a rectangular frame structure of the same length (the length of each modular simulation structure in this embodiment is 1m), with openings on the top and bottom surfaces, and multiple replaceable guide blades 30 are evenly arranged on the side. The guide blades are in the form of spiral, strip, shutter, etc., so as to facilitate the flow of water in the water tank and avoid affecting the experimental results. The above-mentioned modular simulation structures are connected by bolts, which is convenient for installing internal components with guide blades of different forms, and convenient for studying the influence of the structural form of the internal components on the oscillating load.

[0065] As another implementation, the connection method between the box internal component simulation devices 11 is not limited to the bolt connection method proposed above in this embodiment, and other types of existing connection methods that are convenient for disassembly and installation can also be used.

[0066] In addition, a symmetrically arranged visualization window 17 is provided on the shell of the cooling water tank 2. A light source 18 and a high-speed camera 19 are provided at the visualization window 17 for observing the spraying condition of the bubbler in the cooling water tank.

[0067] Embodiment 2

[0068] This embodiment proposes a cooling water tank oscillation analysis method for a nuclear power plant, which is implemented based on a cooling water tank oscillation analysis system for a nuclear power plant provided in the first embodiment, and includes the following steps:

[0069] Step S1, close the drain valve 22 on the drain pipeline of the pressure vessel 1 and the cooling water tank 2, and open the water replenishment valve 20 on the water replenishment pipeline, and then start the water replenishment pump 5 to inject water into the pressure vessel 1 and the cooling water tank 2.

[0070] Step S2: Based on the liquid level sensors in the pressure vessel 1 and the cooling water tank 2, real-time monitoring and acquisition of liquid level data in the pressure vessel 1 and the cooling water tank 2 are performed. When the liquid levels in the pressure vessel 1 and the cooling water tank 2 reach the values ​​required by the experiment, the water supply pump 5 and the water supply valve 20 are closed.

[0071] Step S3, start the measurement module 27 and the data acquisition module 28.

[0072] Step S4: Control the temperature and injection pressure in the pressure vessel to meet the experimental requirements through the control module. Specifically, the heating and heat preservation device 6 on the outer wall of the pressure vessel 1 is controlled to start, heat the water in the pressure vessel, and based on the measurement module, the temperature and pressure and other parameters in the pressure vessel are monitored in real time until the experimental requirements of the injection pressure are met, and then the heating is stopped.

[0073] Step S5, turning on the light source 18 and the high-speed camera 19.

[0074] Step S6, according to the multi-condition experimental requirements of different injection flow rates under different injection pressures, the opening of the multi-stage parallel different intake valves 21 on the intake pipeline 24 is controlled, and the high-temperature and high-pressure water vapor inside the pressure vessel 1 enters the bubbler 9 through the flow measuring device 12, the pressure measuring device 13, and the temperature measuring device 14 in turn, and is sprayed into the cooling water tank 2 through the bubbler 9; in the injection process accompanied by impact-condensation-oscillation, the injection condition of the bubbler is obtained by the high-speed camera 19, and the dynamic pressure sensor installed on the inner wall of the cooling water tank and the simulation device of the internal components of the box is used for measurement, so as to monitor and obtain the dynamic pressure load data inside the cooling water tank in real time.

[0075] In this embodiment, a three-stage parallel intake valve is used, which can be automatically controlled by a control module to realize the opening of different intake valves according to experimental needs, and complete the water tank oscillation load characteristics of multiple working conditions with different injection flow rates under different injection pressures.

[0076] Furthermore, the overpressure exhaust device 7 is arranged on the upper part of the water tank. During the above process, when the pressure in the water tank exceeds the rated value of the overpressure exhaust device 7, the overpressure exhaust device 7 automatically opens to complete the pressure reduction of the water tank, thereby ensuring the integrity of the water tank during the experiment.

[0077] In order to meet the requirements of multi-condition experiments, the experiment also includes:

[0078] (1) Replace the bubbler with a different model to study the effect of bubbler model change on the spray load.

[0079] (2) Replace the simulation device of the internal components of the box with different forms to study the influence of the change of the form of the simulation device of the internal components of the box on the spraying load.

[0080] (3) Adjusting the position of the bubbler in the cooling water tank, including: adjusting the length of the air inlet pipeline 24 and the retractable support device 10 in the vertical direction to adjust the vertical position of the bubbler in the cooling water tank; adjusting the horizontal position of the bubbler in the cooling water tank by adjusting the air inlet pipeline 24 and the retractable support device 10 along the sliding track 29, so as to study the influence of the bubbler position change on the spray load.

[0081] Step S7: After the above experiment is finished, the heating and heat preservation device 6 is turned off, and the water inside the pressure vessel 1 and the cooling water tank 2 is drained through the drainage pipeline 25, so that the experimental device is restored to the initial state before the experiment.

[0082] In addition, for the negative pressure air intake device 8 arranged on the upper part of the cooling water tank, after the spraying test is completed, along with the condensation of water vapor and the decrease in the temperature inside the water tank, the pressure inside the water tank will decrease. When the pressure inside the water tank drops to the rated value of the negative pressure air intake device 8, the negative pressure air intake device 8 automatically opens to complete the air intake of the water tank, thereby ensuring that the water tank is not damaged by negative pressure.

[0083] Step S8: Based on the preset working condition experimental requirements and the data obtained by monitoring, the cooling water tank vibration analysis and research are carried out. That is, the data collected and stored in the data acquisition module are exported, and the subsequent data processing and analysis are carried out in combination with the experimental record data to clarify the influence of different parameters on the water tank vibration load, and provide a theoretical basis and technical basis for the design and improvement of the ADS spray system and water tank structure in the subsequent advanced passive nuclear power plant, and ensure that the bearing performance design of the water tank meets the safety requirements.

[0084] The system and method proposed in this embodiment are designed based on the need to analyze the key influencing factors of the shock load on the water tank caused by the ADS system of the advanced passive nuclear power plant. The system and method can study the influence of different injection pressures, different injection flow rates, different bubbler models, different bubbler immersion depths, different bubbler positions, different tank internal component structures, etc. on the shock load on the water tank, clarify the relationship between the above variables and the shock load, and provide a theoretical basis and technical basis for the design and improvement of the ADS blowing system and water tank structure in the subsequent advanced passive nuclear power plants, thereby improving the safety, reliability and economy of the system design.

[0085] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A cooling water tank oscillation analysis system for a nuclear power plant, characterized in that: Includes a pressure vessel for simulating a pressurizer, and a closed cooling water tank; A bubbler is provided in the cooling water tank, and the pressure vessel is connected to the bubbler through an air inlet pipeline, and the pressure gas is sprayed into the cooling water tank through the bubbler, so as to provide the cooling water tank with test conditions of different pressures and different spray flow rates; The cooling water tank is provided with an internal component simulation device and multiple dynamic pressure sensors. The internal component simulation device is a frame-type structure for supporting the internal structure of the water tank; the multiple dynamic pressure sensors are symmetrically arranged on the inner walls of the cooling water tank and the internal component simulation device, and are used to monitor and obtain the dynamic pressure load data inside the cooling water tank under different test conditions.

2. A cooling water tank oscillation analysis system for a nuclear power plant as claimed in claim 1, characterized in that: The pressure vessel and the cooling water tank are both connected to a water supply module through pipelines, and the water supply module includes a water reservoir; The water reservoir is connected to the water replenishment pump through a pipeline, and then connected to the pressure vessel and the cooling water tank respectively through the water replenishment pipeline, and a water replenishment valve is provided on the water replenishment pipeline; the water replenishment valve and the water replenishment pump are electrically connected to an external control module, and the control module is used to control the opening and closing of the water replenishment valve and the water replenishment pump, so as to control the amount of water in the pressure vessel and the cooling water tank.

3. A cooling water tank oscillation analysis system for a nuclear power plant as claimed in claim 1, characterized in that: The pressure vessel and the cooling water tank are both connected to a drainage module through pipelines, and the drainage module includes a drainage tank; The drainage pool is connected to the pressure vessel and the cooling water tank respectively through drainage pipelines, and the drainage pipelines are provided with drainage valves; the drainage valves are electrically connected to an external control module, and the control module is used to control the opening and closing of the drainage valves, thereby controlling the amount of water in the pressure vessel and the cooling water tank.

4. A cooling water tank oscillation analysis system for a nuclear power plant as claimed in claim 1, characterized in that: The cooling water tank is also provided with an overpressure exhaust device and a negative pressure air intake device, a liquid level measuring device, a retractable support device and a sliding track for automatically controlling and maintaining the pressure in the water tank; wherein the overpressure exhaust device and the negative pressure air intake device are arranged at the top position in the cooling water tank and are arranged outside the internal component simulation device; the bubbler, the retractable support device and the sliding track are all arranged inside the internal component simulation device; The sliding track is fixedly installed on the bottom surface of the cooling water tank, and the bottom of the retractable support device is arranged in the sliding track to realize horizontal movement along the sliding track; one end of the bubbler is connected to the air inlet pipeline through a flange, and the other end of the bubbler is connected to the retractable support device; the bubbler is replaceable and is used to provide test conditions of different bubbler models for the cooling water tank; By adjusting the vertical and horizontal positions of the air intake pipeline and the retractable support device, test conditions with different bubbler positions are provided for the cooling water tank, including: adjusting the vertical position of the bubbler in the cooling water tank by adjusting the vertical length of the air intake pipeline and the retractable support device; and adjusting the horizontal position of the bubbler in the cooling water tank by adjusting the horizontal position of the air intake pipeline and the retractable support device along the sliding track.

5. A cooling water tank oscillation analysis system for a nuclear power plant as claimed in claim 4, characterized in that: The retractable support device comprises a retractable support fixing frame and a shock absorber; One end of the retractable support fixing frame is connected to the bubbler, and the other end is arranged in the sliding track; the shock absorber is arranged on the retractable support fixing frame to absorb vibration energy.

6. A cooling water tank oscillation analysis system for a nuclear power plant as claimed in claim 4, characterized in that: One end of the internal component simulation device is fixed to the bottom surface of the water tank through a base, and the other end contacts the top of the water tank and supports the structural items on the top of the water tank; The internal component simulation device is composed of a plurality of modular simulation structures connected by bolts, each modular simulation structure is a rectangular frame structure of the same length, with openings on the top and bottom surfaces, and a plurality of replaceable guide vanes evenly arranged on the sides, for providing test conditions of different internal component structures for the cooling water tank; the guide vanes are in the form of any one of spiral, strip, and louver types.

7. A cooling water tank oscillation analysis system for a nuclear power plant as claimed in claim 1, characterized in that: The air intake pipeline is provided with multi-stage parallel air intake valves and flow, pressure and temperature measuring devices in sequence; the pressure vessel is provided with pressure, temperature and liquid level measuring devices, and a heating and heat preservation device is provided on the outer wall of the bottom thereof; the heating and heat preservation device is used to heat the water in the pressure vessel to the set temperature and pressure test requirements; Among them, the multi-stage parallel intake valve and the heating and heat preservation device are electrically connected to the external control module, and all sensors and measuring devices are electrically connected to the external data acquisition module.

8. A cooling water tank oscillation analysis system for a nuclear power plant as claimed in claim 1, characterized in that: The shell of the cooling water tank is provided with symmetrically arranged visualization windows, and the visualization windows are provided with a light source and a high-speed camera for observing the spraying condition of the bubbler in the cooling water tank.

9. A cooling water tank oscillation analysis method for a nuclear power plant, characterized in that: A cooling water tank oscillation analysis system for a nuclear power plant according to any one of claims 1 to 8 is implemented, comprising: Control the temperature and injection pressure in the pressure vessel to meet the experimental requirements; According to the multi-operating condition experimental requirements of different injection flow rates under different injection pressures, the opening of different multi-stage parallel-connected intake valves on the intake pipeline is controlled, and the high-temperature and high-pressure water vapor inside the pressure vessel enters the bubbler through the flow, pressure, and temperature measuring devices in turn, and is sprayed into the cooling water tank through the bubbler; During the injection process accompanied by impact-condensation-oscillation, the dynamic pressure load data inside the cooling water tank is monitored and obtained in real time; Based on the preset working condition experimental requirements and the data obtained from monitoring, the cooling water tank oscillation analysis is carried out.

10. A cooling water tank oscillation analysis method for a nuclear power plant as claimed in claim 9, characterized in that: In order to meet the requirements of multi-condition experiments, it also includes: Replace bubblers of different models; Replace different forms of box internal component simulation devices; Adjusting the position of the bubbler in the cooling water tank includes: adjusting the length of the air intake pipeline and the retractable support device in the vertical direction to adjust the vertical position of the bubbler in the cooling water tank; and adjusting the position of the air intake pipeline and the retractable support device along the sliding track in the horizontal direction to adjust the horizontal position of the bubbler in the cooling water tank.

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