A device and method for testing aerosol precipitation of a pressurized water reactor under vibration accident

Abstract

The invention discloses a device and method for testing aerosol sedimentation of a pressurized water reactor under a vibration accident, which relates to the technical field of reactor simulation experimental equipment, including a container, a vibration generating unit, an aerosol generating unit, an aerosol detecting unit and a temperature controlling unit. The invention can detect the diffusion and migration of aerosols in a pressurized water reactor containment under vibration conditions, fully simulates the sedimentation changes of aerosols in the containment under earthquake accidents, and is convenient for technical personnel in this field to know the conditions of aerosols suspended in the pressurized water reactor according to the quantity and particle size of aerosols in the pressurized water reactor containment, and further can judge the harm that the pressurized water reactor will cause to the external atmospheric space under accident conditions, and take corresponding protective measures, which is beneficial to protecting the safety of personnel and property and reducing property losses.

Description

Technical Field

[0001] The invention relates to the technical field of reactor simulation experimental equipment, and in particular to a device and method for testing aerosol precipitation of a pressurized water reactor under vibration accidents. Background Art

[0002] The design of the third-generation AP series nuclear power plants has eliminated the spraying inside the containment and adopted a passive containment cooling system, which can reduce the temperature of the steel containment. The relatively lowered temperature of the containment forms a cold wall, which enhances the temperature gradient between the solid surface and the air space. At the same time, it enhances the condensation of steam inside the containment, affects the thermophoresis and diffusion-phoresis effects of the aerosol, and strengthens the deposition of the aerosol inside the containment.

[0003] In the event of a serious accident at a nuclear power plant, radioactive substances are released in the form of gas, vapor, and aerosol. Aerosols are solid or liquid particles suspended in gas, and are the main carriers of radioactive substances. Their diffusion, distribution, and deposition in space have received special attention in the field of reactor safety in serious accidents.

[0004] The invention patent with application number "201911116391.2" and name "A containment simulation device for aerosol testing" includes a stainless steel body, an upper head and a lower head. The stainless steel body is provided with a manhole, and the side wall is a double-layer jacket structure composed of an inner wall and an outer wall. Between the inner wall and the outer wall, several circular baffles are evenly arranged along the horizontal direction in the vertical direction. The baffles divide the fluid medium space into several layers in the vertical direction, realizing the simulation of the AP1000 passive containment cooling system, and the test conditions of aerosol behavior under severe accident conditions are simulated in detail. In addition, the double-layer jacket structure designed on the outside of the stainless steel body allows the fluid medium to pass through the internal medium space, which improves the original overall fluid space. The horizontal baffles and the bottom plate of each layer of space are horizontal, which can ensure that the temperature distribution inside the containment is evenly layered in the vertical direction, and can simulate the actual working conditions more intuitively.

[0005] In the study "Study on the Effect of Water Vapor Condensation on Aerosol Diffusiophoresis under Severe Accidents" ("Atomic Energy Science and Technology" Vol. 51, No. 1, January 2017), the effect of water vapor condensation on aerosol diffusiophoresis was studied by setting up steam generators and other devices.

[0006] However, so far, there is no device or experiment to test the distribution of aerosols in the containment after an earthquake. Summary of the invention

[0007] The purpose of the present invention is to provide a device and method for testing aerosol sedimentation in a pressurized water reactor under vibration accidents, so as to solve the problems existing in the above-mentioned prior art. It is capable of detecting the diffusion and migration of aerosols in the containment of a pressurized water reactor under vibration conditions, and fully simulating the sedimentation changes of aerosols in the containment under earthquake accidents.

[0008] To achieve the above-mentioned purpose, the present invention provides the following scheme: The present invention provides a device for testing aerosol sedimentation of a pressurized water reactor under a vibration accident, comprising a container, a vibration generating unit, an aerosol generating unit, an aerosol detecting unit and a temperature controlling unit; the container is used to simulate the containment of a pressurized water reactor, the aerosol generating unit is connected to the cavity inside the container, and is used to fill the cavity with aerosol, the vibration generating unit is used to drive the container filled with aerosol to vibrate, the temperature controlling unit is used to adjust the temperature of the cavity and provide the external environment temperature, the aerosol detecting unit is connected to the cavity, and is used to measure the distribution of aerosol in the cavity after vibration and temperature change occur; the container is also provided with a temperature sensor and a pressure sensor, and the temperature sensor and the pressure sensor are used to monitor the temperature and pressure inside the cavity in real time.

[0009] Preferably, the vibration generating unit includes an electrically connected swept frequency signal generator, a power amplifier, an exciter and a vibration data collector, wherein the exciter is also connected to the container to drive the container to vibrate; the vibration data collector is used to detect the vibration parameters of the container and feed back to the control system, and the control system adjusts the output frequency of the swept frequency signal generator and the output current of the power amplifier according to the feedback signal of the vibration data collector to ensure that the container vibrates under the set vibration parameters.

[0010] Preferably, the aerosol detection unit includes a detector and a first pipeline, a second pipeline and a third pipeline, each of which has one end connected to the detector, the other ends of the first pipeline and the third pipeline are respectively connected to the side wall and the bottom of the cavity, and the other end of the second pipeline extends to the center of the cavity.

[0011] Preferably, the detector includes a particle size spectrometer, and a pressure reducing valve, a solenoid valve and a pressure reducing orifice are sequentially arranged on the connecting pipelines of the first pipeline, the second pipeline, the third pipeline and the particle size spectrometer.

[0012] Preferably, the temperature control unit comprises a steam generator, and the steam generator is communicated with the cavity.

[0013] Preferably, the temperature control unit further comprises a medium coil wrapped on the outer wall of the container and a medium temperature controller connected to the medium coil.

[0014] Preferably, the aerosol generating unit comprises an air compressor and an aerosol generator, and the aerosol generator is arranged between the container and the air compressor.

[0015] Preferably, a cleaning pipeline is further provided between the air compressor and the container, a drainage gas pipeline is provided at the bottom of the container, and the drainage gas pipeline is connected to a water tank and a collection tank in sequence.

[0016] Preferably, the container is fixed on a supporting frame.

[0017] The present invention also provides a method for testing aerosol precipitation of a pressurized water reactor under vibration accident, comprising the following steps:

[0018] 1) Turn on the air compressor and cleaning pipeline, and use the air compressor to clean the cavity of the container;

[0019] 2) After cleaning is completed, the cavity is emptied, and the air compressor provides an air source to prompt the aerosol generator to generate aerosol and pass it into the cavity;

[0020] 3) Turn on the steam generator, introduce steam into the cavity until the temperature inside the cavity reaches the set level, and turn on the medium temperature controller to simulate the external ambient temperature;

[0021] 4) Turn on the vibration generating unit to vibrate the container. After vibrating for a period of time or the temperature in the cavity reaches a set value, turn off the vibration generating unit and the temperature control unit, and select to open the stop valve on the first pipeline, the second pipeline or the third pipeline. Use a particle size spectrometer to measure the change in aerosol particle size on the side wall of the cavity, the center of the cavity or the bottom of the cavity when the container vibrates; at the same time, the temperature sensor and the pressure sensor measure the temperature and pressure in the cavity.

[0022] Compared with the prior art, the present invention has achieved the following technical effects:

[0023] 1. The present invention can detect the diffusion and migration of aerosols in the containment of a pressurized water reactor under vibration conditions, fully simulate the sedimentation changes of aerosols in the containment under earthquake accidents, and according to the number and particle size of aerosols in the containment of a pressurized water reactor, it is convenient for those skilled in the art to know the state of aerosols suspended in the pressurized water reactor, and then judge the harm that the pressurized water reactor will cause to the external atmosphere under accident conditions, and take corresponding protective measures, which is conducive to protecting the safety of personnel and property and reducing property losses;

[0024] 2. In the present invention, the first pipeline, the second pipeline, and the third pipeline are used to detect aerosols at different positions inside the cavity, which can more accurately reflect the aerosol distribution state inside the containment when an accident occurs;

[0025] 3. The present invention is also provided with a cleaning pipeline, which can clean the container before testing, empty the internal impurities and the aerosol remaining from the previous test, and improve the accuracy of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0027] Figure 1 It is a schematic diagram of the overall structure of the testing device in the present invention;

[0028] Among them, 1. container; 2. temperature sensor; 3. pressure sensor; 4. swept frequency signal generator; 5. power amplifier; 6. exciter; 7. vibration data collector; 8. particle size spectrometer; 9. pressure reducing valve; 10. solenoid valve; 11. pressure reducing orifice; 12. air compressor; 13. aerosol generator; 14. water tank; 15. collection tank; 16. support frame; 17. safety valve; 18. medium coil; 19. medium temperature controller; 20. steam generator; 21. filter; 22. first stop valve; 23. second stop valve; 24. fourth stop valve; 25. fifth stop valve; 26. seventh stop valve; 27. eighth stop valve; 28. ninth stop valve; 29. ​​tenth stop valve; 30. eleventh stop valve; 31. twelfth stop valve. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiment is only a sub-embodiment of a unit of the present invention, rather than an embodiment of the whole unit. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] The purpose of the present invention is to provide a device and method for testing aerosol sedimentation in a pressurized water reactor under vibration accidents, so as to solve the problems existing in the above-mentioned prior art. It is capable of detecting the diffusion and migration of aerosols in the containment of a pressurized water reactor under vibration conditions, and fully simulating the sedimentation changes of aerosols in the containment under earthquake accidents.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Embodiment 1:

[0033] The present embodiment provides a device for testing aerosol sedimentation of a pressurized water reactor under a vibration accident, comprising a container 1, a vibration generating unit, an aerosol generating unit, an aerosol detecting unit and a temperature controlling unit. The aerosol generating unit and the aerosol detecting unit are both connected to the cavity inside the container 1. The container 1 is also provided with a temperature sensor 2 and a pressure sensor 3.

[0034] During the test, the aerosol generating unit fills the cavity with aerosol, the temperature control unit makes the aerosol storage environment temperature reach the set level, and then the vibration generating unit drives the container 1 filled with aerosol to vibrate, simulating the working conditions of an earthquake or other severe vibration accidents, and then adjusts the temperature control unit (it can be directly cut off to simulate the natural cooling situation, or it can be set to a constant temperature to simulate the temperature of the external environment of the containment). When the cavity temperature drops to a certain level (which can be set by yourself), the vibration generating unit and the temperature control unit are turned off, and the distribution of aerosol in the cavity is measured by the aerosol detection unit; the temperature sensor 2 and the pressure sensor 3 are used to monitor the temperature and pressure inside the cavity in real time. By changing the vibration frequency, vibration amplitude, and vibration time of the container 1, the distribution of aerosol inside the cavity (including the number of aerosols, particle size and other parameters) under different vibration conditions can be detected.

[0035] Therefore, this embodiment can detect the diffusion and migration of aerosols in the containment of a pressurized water reactor under vibration conditions, and can fully simulate the sedimentation changes of aerosols in the containment under earthquake accidents (including but not limited to earthquake accidents, and also including other vibration accidents). According to the number and particle size distribution of aerosols in the containment of the pressurized water reactor, it is convenient for technical personnel in this field to know the status of aerosols suspended in the pressurized water reactor, and then be able to judge the harm that the pressurized water reactor will cause to the external atmospheric space under accident conditions, and take corresponding protective measures, which is beneficial to protecting the safety of personnel and property and reducing property losses.

[0036] Specifically, the vibration generating unit in this embodiment includes an electrically connected sweep signal generator 4, a power amplifier 5, an exciter 6 and a vibration data collector 7, and the vibration output end of the exciter 6 is fixed on the container 1; in the process of vibration generation, the vibration data collector 7 is used to detect the vibration parameters of the container 1 (such as frequency, vibration force and acceleration, etc.), and feed back to the control system, and the control system adjusts the output frequency of the sweep signal generator 4 and the output current of the power amplifier 5 according to the feedback signal of the vibration data collector 7 and in combination with the parameters of the container 1 itself (size, weight, etc.) to obtain the set vibration parameters of the container 1; the sweep signal generator 4, the power amplifier 5, the exciter 6 and the vibration data collector 7 are all commonly used equipment in this field, and their structures and working principles are not repeated in this embodiment.

[0037] Since the aerosols in various places in the cavity may be unevenly distributed during the vibration process, in order to detect the aerosols at different positions in the cavity and accurately grasp the aerosol distribution inside the cavity, the aerosol detection unit in this embodiment includes a detector and a first pipeline, a second pipeline and a third pipeline, each of which is connected to the detector at one end, the other ends of the first pipeline and the third pipeline are respectively connected to the side wall and the bottom of the cavity, and the other end of the second pipeline extends to the center of the cavity; and a ninth stop valve 28, a tenth stop valve 29 and a twelfth stop valve 31 are respectively provided on the first pipeline, the second pipeline and the third pipeline. During operation, the ninth stop valve 28, the tenth stop valve 29 or the twelfth stop valve 31 is selected to open to detect the aerosols at different positions in the cavity.

[0038] Furthermore, the detector includes a particle size spectrometer 8, and the connecting pipelines between the first pipeline, the second pipeline, the third pipeline and the particle size spectrometer 8 are also provided with a pressure reducing valve 9, a solenoid valve 10 and a pressure reducing orifice 11 in sequence to prevent damage to the particle size spectrometer caused by the impact of high pressure gas.

[0039] Furthermore, the temperature control unit in this embodiment includes a steam generator 20, which is connected to the cavity through an eleventh stop valve 30, and is used to introduce steam into the cavity to provide the core temperature and study the distribution state of the internal aerosol in the case of steam leakage. In actual operation, the steam temperature cannot reach the actual core temperature, but can still reach 150°C to 200°C, thereby providing guidance for the aerosol distribution in vibration accidents or steam leakage accidents. It should be noted that the steam generator 20 can be turned on at the same time as the vibration generating unit, or only the steam generator 20 can be turned on to achieve simulation of complex earthquake-water vapor leakage accidents, single accident conditions of water vapor leakage only, and vibration accident conditions only.

[0040] In this embodiment, the temperature control unit further includes a medium coil 18 wrapped around the outer wall of the container 1 and a medium temperature controller 19 connected to the medium coil 18. The medium temperature controller 19 heats or cools the medium to simulate changes in the external environment temperature.

[0041] In this embodiment, the aerosol generating unit includes an air compressor 12 and an aerosol generator 13 . The aerosol generator 13 is disposed between the container 1 and the air compressor 12 . The air compressor 12 is used to deliver the aerosol generated by the aerosol generator 13 into the container 1 .

[0042] Furthermore, in this embodiment, a cleaning pipeline is also provided between the air compressor 12 and the container 1, and a drainage gas pipeline is provided at the bottom of the container 1, and the drainage gas pipeline is connected to the water tank 14 and the collecting tank 15 in sequence. The cleaning pipeline is used to clean the cavity before detection to prevent other impurities from affecting the distribution of aerosols during the detection process, and the water tank 14 and the collecting tank 15 are both used to collect moisture to avoid environmental pollution.

[0043] Furthermore, in this embodiment, the container 1 is fixed on a support frame 16 .

[0044] In this embodiment, the container 1 is also provided with a safety valve 17 to prevent the container 1 from being damaged by excessive pressure inside the cavity; and each pipeline is also provided with a stop valve, and the use of the stop valve is described in detail in Example 2.

[0045] Embodiment 2:

[0046] This embodiment provides a method for testing aerosol deposition of a pressurized water reactor under vibration accident, comprising the following steps:

[0047] 1) Before the test, all valves are closed, and the seventh stop valve 26, the eighth stop valve 27, the fifth stop valve 25, and the first stop valve 22 are opened. The gas generated by the air compressor 12 is filtered by the filter 21 and then enters the container 1. The container 1 is cleaned, and the discharged water is finally collected by the collection tank 15 after passing through the water tank 14;

[0048] 2) After cleaning, close the first stop valve 22, the fifth stop valve 25, the eighth stop valve 27, and the seventh stop valve 26 in sequence; after opening the first stop valve 22, the second stop valve 23, and the fourth stop valve 24, start the air compressor 12 to allow the air flow to pass through the aerosol generator 13 to fill the aerosol into the cavity; after the aerosol is filled, close all valves, open the eleventh stop valve 30 and the steam generator 20, fill steam into the container 1 so that the internal temperature of the container 1 reaches a certain value, then close the steam generator 20, turn on the medium temperature controller 19, and simulate the external ambient temperature of the containment.

[0049] 3) Turn on the sweep signal generator 4 and the power amplifier 5, and make the vibration exciter 6 drive the container 1 to vibrate at a certain frequency (simulating an earthquake). The exciting force can be obtained by the vibration data collector 7 connected to the vibration exciter 6.

[0050] 4) When the temperature in the container 1 drops to a certain level or the vibration time reaches the required test time, turn off the power amplifier 5, stop the exciter 6, and turn off the medium temperature controller 19; choose to open the tenth stop valve 29, and use the particle size spectrometer 8 to measure the particle size change of the aerosol in the central area of ​​the container 1; choose to close the tenth stop valve 29 and open the ninth stop valve 28 to measure the particle size change of the aerosol near the wall of the container 1; choose to close the ninth stop valve 28 and open the twelfth stop valve 31 to measure the particle size change of the aerosol near the bottom of the container 1.

[0051] In addition, after step 2), the steam generator 20 is turned on again and steam is introduced into the container 1 for a certain period of time, which can simulate the occurrence of a steam leakage accident, and the particle size distribution change of the aerosol in the container 1 is measured by the particle size spectrometer 8; when the container 1 vibrates, steam is introduced for a certain period of time to simulate the situation where a vibration accident and a steam leakage accident occur at the same time.

[0052] Adaptive changes made according to actual needs are all within the protection scope of the present invention.

[0053] It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numerals in the claims should not be regarded as limiting the claims involved.

Claims

1. A device for testing aerosol precipitation of a pressurized water reactor under vibration accidents, characterized in that: It comprises a container, a vibration generating unit, an aerosol generating unit, an aerosol detecting unit and a temperature controlling unit; the container is used to simulate a pressurized water reactor containment shell, the aerosol generating unit is connected to the cavity inside the container, and is used to fill the cavity with aerosol, the vibration generating unit is used to drive the container filled with aerosol to vibrate, the temperature controlling unit is used to adjust the cavity temperature and provide the external environment temperature, the aerosol detecting unit is connected to the cavity, and is used to measure the distribution of aerosol in the cavity after vibration and temperature change occur; the container is also provided with a temperature sensor and a pressure sensor, and the temperature sensor and the pressure sensor are used to monitor the temperature and pressure inside the cavity in real time; The aerosol generating unit includes an air compressor and an aerosol generator, wherein the aerosol generator is arranged between the container and the air compressor; a cleaning pipeline is also arranged between the air compressor and the container, and a drainage gas pipeline is arranged at the bottom of the container, and the drainage gas pipeline is connected to a water tank and a collection tank in sequence.

2. The device for testing aerosol deposition of a pressurized water reactor under vibration accident according to claim 1, characterized in that: The vibration generating unit includes an electrically connected sweep frequency signal generator, a power amplifier, an exciter and a vibration data collector. The exciter is also connected to the container to drive the container to vibrate. The vibration data collector is used to detect the vibration parameters of the container and feed back to the control system. The control system adjusts the output frequency of the sweep frequency signal generator and the output current of the power amplifier according to the feedback signal of the vibration data collector to ensure that the container vibrates under the set vibration parameters.

3. The device for testing aerosol deposition of a pressurized water reactor under vibration accident according to claim 1 or 2, characterized in that: The aerosol detection unit includes a detector and a first pipeline, a second pipeline and a third pipeline, each of which has one end connected to the detector; the other ends of the first pipeline and the third pipeline are respectively connected to the side wall and the bottom of the cavity; the other end of the second pipeline extends to the center of the cavity.

4. The device for testing aerosol deposition of a pressurized water reactor under vibration accident according to claim 3 is characterized in that: The detector comprises a particle size spectrometer, and a pressure reducing valve, a solenoid valve and a pressure reducing orifice are sequentially arranged on the connecting pipelines of the first pipeline, the second pipeline, the third pipeline and the particle size spectrometer.

5. The device for testing aerosol deposition of a pressurized water reactor under vibration accident according to claim 4, characterized in that: The temperature control unit includes a steam generator, and the steam generator is communicated with the cavity.

6. The device for testing aerosol deposition of a pressurized water reactor under vibration accident according to claim 5, characterized in that: The temperature control unit further comprises a medium coil wrapped on the outer wall of the container and a medium temperature controller connected to the medium coil.

7. The device for testing aerosol deposition of a pressurized water reactor under vibration accident according to claim 1, characterized in that: The container is fixed on a supporting frame.

8. A method for testing aerosol deposition in a pressurized water reactor under vibration accidents, characterized in that: The following steps are involved: 1) Turn on the air compressor and cleaning pipeline, and use the air compressor to clean the cavity of the container; 2) After cleaning is completed, the cavity is emptied, and the air compressor provides an air source to prompt the aerosol generator to generate aerosol and pass it into the cavity; 3) Turn on the steam generator, introduce steam into the cavity until the temperature inside the cavity reaches the set level, and turn on the medium temperature controller to simulate the external ambient temperature; 4) Turn on the vibration generating unit to vibrate the container. After vibrating for a period of time or the temperature in the cavity reaches a set value, turn off the vibration generating unit and the temperature control unit, and select to open the stop valve on the first pipeline, the second pipeline or the third pipeline. Use a particle size spectrometer to measure the change in aerosol particle size on the side wall of the cavity, the center of the cavity or the bottom of the cavity when the container vibrates; at the same time, the temperature sensor and the pressure sensor measure the temperature and pressure in the cavity.

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