Experimental apparatus and method for condensate water flush of wall-attached aerosol

Abstract

The application provides an experimental detection device and method for condensate water flushing wall-attached aerosol, relates to the technical field of nuclear power plant safety, and the device comprises a simulation box, a steam supply system, an aerosol supply system and a simulation plate body. The simulation box is arranged in an experimental cavity and has a condensing panel on the surface. The method comprises the following steps: setting the simulation plate body at a preset inclination angle, introducing the aerosol, cleaning the aerosol in a non-experimental area, introducing steam, introducing a heat exchange medium into the simulation plate body, condensing the steam on the surface of the condensing panel and flushing the aerosol, collecting and weighing the flushing liquid and the remaining aerosol that is not flushed away, separating the aerosol and the condensate water in the flushing liquid and weighing them, and calculating the aerosol attachment density, the aerosol flushing rate in different preset time periods, and the change rule of the aerosol flushing rate with time. The application can simulate the process that the radioactive aerosol attached to the surface in the reactor containment after a safety accident is flushed and then migrates by the steam condensate, and provides a basis for accident evaluation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nuclear power plant safety, in particular to an experimental detection device and method for condensate flushing wall-attached aerosol. BACKGROUND

[0002] When a LOCA accident or other coolant loss accident occurs in a nuclear power plant reactor, a large amount of coolant leaks from the break to the reactor containment. Due to the relatively low pressure in the containment, a large amount of steam will be generated in the containment, and a large amount of radioactive material will be released into the air from the pipe break, and then dispersed in the form of aerosol in the reactor containment, and attached to the wall or structure surface in the containment. A part of the surface-attached radioactive aerosol will remain on the wall or structure surface, and the other part of the radioactive aerosol will be flushed down by the condensate formed by the steam and continue to migrate, and finally flow to the floor or pit along with the steam condensate.

[0003] The process of the surface-attached radioactive aerosol being flushed and migrated by the steam condensate will directly affect the distribution change of the radioactivity after the accident in the nuclear power plant. Accurate evaluation of this process is of great significance to the evaluation or mitigation of the radioactivity in the nuclear power plant after the accident. The existing experimental detection equipment cannot truly simulate the process of the surface-attached radioactive aerosol being flushed and migrated by the steam condensate in the reactor containment after the accident, and cannot accurately evaluate the distribution change of the radioactivity in the nuclear power plant after the accident. SUMMARY

[0004] The present application provides an experimental detection device and method for condensate flushing wall-attached aerosol, which is used to simulate the process of the surface-attached radioactive aerosol being flushed and migrated by the steam condensate in the reactor containment after the safety accident, so as to accurately evaluate the distribution change of the surface-attached radioactive aerosol in the reactor containment after the accident.

[0005] In one aspect of the present application, an experimental detection device for condensate flushing wall-attached aerosol is provided, which comprises: a simulation box body, an experimental cavity for simulating the internal environment of the reactor containment is arranged inside; a steam supply system connected with the experimental cavity through a steam output pipeline to introduce steam into the experimental cavity; an aerosol supply system connected with the experimental cavity through a steam output pipeline to introduce aerosol into the experimental cavity; a simulation plate body arranged in the experimental cavity at a preset inclined angle, and a heat exchange medium flows inside, and a condensation panel is arranged on the surface, the condensation panel exchanges heat with the heat exchange medium, so that the steam in the experimental cavity is condensed on the surface of the condensation panel, and the aerosol attached to the condensation panel is flushed.

[0006] In some embodiments, the experimental detection device for condensate flushing wall-attached aerosol further comprises a support arranged in the experimental cavity, the simulation plate body is movably connected to the support and is at least partially free and swings up and down relative to the support, and an angle adjusting mechanism is arranged between the support and the simulation plate body to manually or automatically adjust the height of the free end of the simulation plate body relative to the support, thereby changing the preset inclination angle of the simulation plate body to simulate a plane with different inclination angles in the reactor containment.

[0007] In some embodiments, the condensation panel is detachably connected to the simulation plate body, and the surfaces of different condensation panels are provided with different degrees of smoothness, or the surfaces of different condensation panels are provided with different surface materials or surface coatings; or the condensation panel is integrally formed on the simulation plate body, and the surfaces of the condensation panels of different simulation plate bodies are provided with different degrees of smoothness, or the condensation panels of different simulation plate bodies are provided with different surface materials or surface coatings.

[0008] In some embodiments, the simulation box is provided with a heat preservation structure for preventing heat exchange between the experimental cavity and the outside space, and a heating structure for heating at least part of the experimental cavity, and the heating structure is away from the simulation plate body.

[0009] In some embodiments, the simulation box is provided with a pressure relief pipeline for communicating the experimental cavity with the outside space, and the pressure relief pipeline is provided with a pressure relief valve.

[0010] In some embodiments, the experimental detection device for condensate flushing wall-attached aerosol further comprises a heat exchange medium supply system connected to the simulation plate body through a heat exchange medium circulation pipeline to circulate a heat exchange medium into the simulation plate body and exchange heat with the condensation panel.

[0011] In some embodiments, the experimental detection device for condensate flushing wall-attached aerosol further comprises a liquid collecting device arranged at the low end of the simulation plate body in the direction of gravity and having a collection groove communicating with the condensation panel to collect the flushing liquid mixed with the aerosol condensed and flowing down from the surface of the condensation panel.

[0012] In some embodiments, the simulation plate body is provided with a fence surrounding the periphery of the condensation panel, and an opening is arranged at one end of the fence facing the collection groove to guide the flushing liquid on the condensation panel to the collection groove.

[0013] In another aspect of the present application, an experimental detection method of condensate water flushing wall-attached aerosol is provided, which is applied to the experimental detection device of condensate water flushing wall-attached aerosol as described in any one of the above aspects, and comprises the following steps:

[0014] S100, setting the simulation plate body at a preset inclination angle to simulate a plane with a specific inclination angle in a reactor containment vessel through the condensation panel; maintaining the airtight state of the simulation box, and introducing aerosol into the experimental cavity according to a set introduction time.

[0015] S200, after the aerosol is introduced, the aerosol in the non-experimental area of the experimental cavity is cleaned, and only the aerosol attached to the condensation panel is reserved to simulate the attachment of radioactive aerosol on the plane in the reactor containment vessel after an accident occurs.

[0016] S300, introducing steam into the experimental cavity, and introducing heat exchange medium into the simulation plate body to cool the condensation panel, so that the steam condenses on the surface of the condensation panel and forms a liquid flow, and then the aerosol attached to the condensation panel is flushed by the liquid flow to simulate the process of aerosol being flushed and re-migrating by steam condensate after being attached to the plane in the reactor containment vessel.

[0017] S400, collecting the flushing liquid mixed with aerosol condensed and flowed down from the surface of the condensation panel in batches according to a preset time interval, stopping the introduction of steam when the turbidity of the flushing liquid collected at last is close to that of water, and completing a simulation experiment.

[0018] S500, collecting the remaining aerosol on the surface of the condensation panel which is not flushed away and weighing to obtain the residual mass of aerosol; separating the aerosol and condensate water in the flushing liquid collected in each preset time period and weighing to obtain the aerosol flushing mass and the condensate water volume in each preset time period; and calculating the attachment density of aerosol, the aerosol flushing rate in different preset time periods, and the change rule of the aerosol flushing rate with time in the simulation experiment according to the weighing results.

[0019] In some embodiments, the experimental detection method of condensate water flushing wall-attached aerosol further comprises: S600, changing the preset inclination angle of the simulation plate body, or / and changing the surface smoothness of the condensation panel, or / and changing the surface material or surface coating of the condensation panel, and then performing the operations of S100 to S500.

[0020] The experimental detection device and method for condensate water flushing wall-attached aerosol provided by the application simulate the internal environment of the reactor containment through the experimental cavity in the simulation box; simulate the wall surface or structural plane with a specific inclination angle in the containment through the condensing panel on the simulation plate; simulate the environment in which the containment is filled with steam after a reactor safety accident through the steam supply system to introduce steam into the experimental cavity; simulate the dispersion and adhesion of radioactive aerosol in the containment after a reactor safety accident through the aerosol supply system to introduce aerosol into the experimental cavity. During the simulation experiment detection process, the condensing panel is cooled by the heat exchange medium, which promotes the condensation of steam in the experimental cavity into a liquid stream on the surface of the condensing panel, and the aerosol attached to the condensing panel is flushed by the condensed liquid stream, which can truly simulate the process of the surface-attached radioactive aerosol in the reactor containment being flushed and re-migrated by the steam condensate after a safety accident. The application collects the flushing liquid mixed with aerosol condensed and flowed down from the surface of the condensing panel in batches according to the preset time interval, and calculates the law of the steam condensate flushing aerosol in the experimental cavity through the detection of the amount of condensate water and aerosol in the flushing liquid collected in each preset time period, which provides a reliable simulation experiment detection basis for accurately evaluating the distribution change of the attached radioactive aerosol in the reactor containment after an accident. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings, wherein:

[0022] Figure 1 The structural schematic diagram of one specific embodiment of the application includes a simulation box, a steam supply system, an aerosol supply system, a heat exchange medium supply system, and a liquid collecting device.

[0023] Figure 2 The simulation box and its internal structure schematic diagram of one specific embodiment of the application;

[0024] Figure 3 The connection structure schematic diagram of the heat exchange medium supply system, the simulation plate, and the liquid collecting device of one specific embodiment of the application;

[0025] Figure 4 The horizontal cross-sectional structure schematic diagram of the simulation plate of one specific embodiment of the application;

[0026] Figure 5 The connection structure schematic diagram of the simulation plate, the support, the angle adjusting mechanism, and the liquid collecting device of one specific embodiment of the application. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Any person skilled in the art can obtain all other embodiments based on the embodiments in the present application without any creative effort, which shall fall within the scope of the present application. In addition, any proper combination of the features, operations or characteristics described in the specification can form various embodiments. Meanwhile, the order of the steps or actions in the method description can be adjusted or changed in a manner obvious to those skilled in the art. Therefore, the order in the specification and the drawings is only for clearly describing an embodiment, and does not mean a necessary order, unless otherwise specified.

[0028] Referring to Figures 1 to 2 The present application provides an experimental detection device for condensate water flushing wall-attached aerosol, which comprises a simulation box 1, a steam supply system 2, an aerosol supply system 3 and a simulation plate body 4. The simulation box 1 is internally provided with an experimental cavity 10 for simulating the internal environment of a reactor containment. The steam supply system 2 is connected with the experimental cavity 10 in the simulation box 1 through a steam output pipeline 20 to introduce steam into the experimental cavity 10. The aerosol supply system 3 is connected with the experimental cavity 10 in the simulation box 1 through an aerosol output pipeline 30 to introduce aerosol (not shown in the figure) into the experimental cavity 10. The simulation plate body 4 is arranged in the experimental cavity 10 of the simulation box 1 at a preset inclined angle, and a heat exchange medium (not shown in the figure) flows in the interior of the simulation plate body 4. The surface of the simulation plate body 4 is provided with a condensing panel 40, which exchanges heat with the heat exchange medium flowing in the interior of the simulation plate body 4, so that the steam in the experimental cavity 10 condenses on the surface of the condensing panel 40 and forms a liquid flow, and the aerosol attached to the condensing panel 40 is flushed by the formed liquid flow.

[0029] The experimental detection device for condensate water flushing wall-attached aerosol provided by the application simulates the internal environment of the reactor containment through the experimental cavity 10 in the simulation box 1; simulates the wall surface or structure plane with a specific inclination angle in the containment through the condensing panel 40 on the simulation plate body 4; simulates the environment in which the containment is filled with steam after a reactor safety accident through the steam supply system 2 to introduce steam into the experimental cavity 10; and simulates the dispersion and adhesion of radioactive aerosol in the containment after a reactor safety accident through the aerosol supply system 3 to introduce aerosol into the experimental cavity 10. During the simulation experiment, the condensing panel 40 is cooled by the heat exchange medium, so that the steam in the experimental cavity 10 condenses into a liquid stream on the surface of the condensing panel 40, and the aerosol attached to the condensing panel 40 is flushed by the condensed liquid stream, which can truly simulate the process in which the surface-attached radioactive aerosol in the reactor containment after a safety accident is flushed and re-migrated by the steam condensate. The application collects the flushing liquid mixed with the aerosol, which is condensed and flows down from the surface of the condensing panel 40, in batches according to preset time intervals, and calculates the law of the steam condensate flushing aerosol in the experimental cavity 10 by detecting the amount of the condensate water and the aerosol in the flushing liquid collected in each preset time period, which provides a reliable simulation experiment basis for accurately evaluating the distribution change of the attached radioactive aerosol in the reactor containment after an accident.

[0030] Please refer to Figure 2 In some embodiments, the simulation box 1 is provided as a combined closed heat exchange device, and the inner cavity of the simulation box 1 constitutes the experimental cavity 10. The space of the experimental cavity 10 should be able to accommodate enough steam and aerosol. The simulation plate body 4 is arranged at the bottom of the experimental cavity 10 according to a preset inclination angle, so as to facilitate the adhesion and settlement of the aerosol on the condensing panel 40.

[0031] Preferably, the simulation box 1 is provided with a manhole (not shown in the figure) connected to the experimental cavity 10, so that the experimental personnel can enter and exit the experimental cavity 10 through the manhole, and transfer experimental articles such as the simulation plate body 4 in and out of the experimental cavity 10 through the manhole. The manhole is detachably connected with a manhole cover (not shown in the figure), so as to close the manhole by the manhole cover and maintain the closed environment in the experimental cavity 10 when needed. The simulation box 1 is provided with at least one steam inlet flange 11 connected to the experimental cavity 10 and at least one aerosol inlet flange 12 connected to the experimental cavity 10. The steam inlet flange 11 is connected with the steam supply system 2 through a steam output pipeline 20, so as to introduce steam into the experimental cavity 10. The aerosol inlet flange 12 is connected with the aerosol supply system 3 through an aerosol output pipeline 30, so as to introduce aerosol into the experimental cavity 10. The steam inlet flange 11 and the aerosol inlet flange 12 can be arranged on the same side or different sides. The steam inlet flange 11 and the aerosol inlet flange 12 can be arranged on the side wall of the simulation box 1 or on the top wall of the simulation box 1, which is not limited in the application.

[0032] In order to ensure that the aerosol in the experimental cavity 10 can be fully dispersed and attached to the condensing panel 40 of the simulation plate body 4, the setting height of the aerosol inlet flange 12 is at least higher than the highest position of the simulation plate body 4 in the direction of gravity.

[0033] Referring to Figure 2 In some embodiments, the simulation box 1 is provided with a heat preservation structure 13 for preventing heat exchange between the experimental cavity 10 and the external space, and a heating structure 14 for heating at least part of the experimental cavity 10, wherein the heating structure 14 is away from the simulation plate body 4.

[0034] Preferably, the heating structure 14 can be an electric heating wire uniformly arranged on the outer wall of the simulation box 1 and avoiding the placement area of the simulation plate body 4, and the heat preservation structure 13 can be a heat preservation plate attached to the outer wall of the simulation box 1 and protecting the electric heating wire inside.

[0035] The present application isolates the experimental cavity 10 from the external space of the simulation box 1 through the heat preservation structure 13 to prevent heat exchange between the experimental cavity 10 and the external space, and at the same time heats part of the internal area of the experimental cavity 10 through the heating structure 14, which is beneficial to maintain the temperature of the local vapor away from the simulation plate body 4 inside the experimental cavity 10 constant, keep the vapor environment inside the experimental cavity 10 stable, and ensure that the vapor can be condensed on the condensing panel 40 at a constant rate.

[0036] Referring to Figure 1 and Figure 2 In some embodiments, the simulation box 1 is provided with a pressure relief pipeline 15 for connecting the experimental cavity 10 with the external space, and the pressure relief pipeline 15 is provided with a pressure relief valve 16.

[0037] During the experiment, the experimental cavity 10 can be connected or isolated with the external space of the simulation box 1 by opening and closing the pressure relief valve 16. For example, during the process that the aerosol supply system 3 introduces the aerosol into the experimental cavity 10, the pressure relief valve 16 should be completely closed to maintain the airtightness of the experimental cavity 10, prevent external airflow from entering the experimental cavity 10 to affect the distribution of the aerosol and deposit impurities other than the aerosol on the condensing panel 40, and further interfere with the accuracy of the experimental results. During the process that the vapor supply system 2 introduces the vapor into the experimental cavity 10, the pressure relief valve 16 can be set to be completely opened or partially opened, so that part of the vapor can be discharged through the pressure relief pipeline 15, preventing the problem of excessive internal vapor pressure of the experimental cavity 10 caused by equipment failure and the like, and being safer.

[0038] It can be understood that the pressure relief valve 16 can also be arranged to automatically open when the pressure in the experimental chamber 10 is sensed to exceed a safety threshold, preventing the problem of excessive steam pressure inside the experimental chamber 10 caused by equipment failure or the like, and being safer.

[0039] Referring to Figure 1 In some embodiments, the steam supply system 2 preferably comprises an electric heating boiler 21, the steam output end of which is connected to the steam output pipeline 20, and the steam output pipeline 20 is provided with a steam output control valve 22 for controlling the steam output amount, a steam flow meter 23 for detecting the steam output flow, a steam pressure gauge 24 for detecting the steam pressure, and a steam thermometer 25 for detecting the steam output temperature. During the simulation experiment, the opening degree of the steam output control valve 22 can be adjusted accordingly by the feedback of the corresponding parameter values of the steam from the steam flow meter 23, the steam pressure gauge 24, and the steam thermometer 25, so as to control the amount of steam output from the steam supply system 2 into the experimental chamber 10, so as to simulate the steam environment in the reactor containment under real conditions.

[0040] Referring to Figure 1 In some embodiments, the aerosol supply system 3 preferably comprises a gas tank 31 and an aerosol generator 32, the aerosol generator 32 being connected between the aerosol output pipeline 30 and the gas tank 31, and the gas tank 31 storing compressed carrier gas for pressurizing the carrier gas into the aerosol generator 32, and the carrier gas carrying the aerosol generated by the aerosol generator 32 and finally outputting to the experimental chamber 10. The aerosol output pipeline 30 is provided with a carrier gas flow meter 33 for detecting the output flow of the carrier gas, and an aerosol output control valve 34 for controlling the output amount of the aerosol. During the simulation experiment, the output flow of the carrier gas can be detected by the carrier gas flow meter 33, and the opening degree of the aerosol output control valve 34 can be adjusted according to the experimental requirements, so as to control the amount of aerosol output from the aerosol supply system 3 into the experimental chamber 10, so as to simulate the dispersion and adhesion of radioactive aerosol in the reactor containment under real conditions.

[0041] Referring to Figure 2 and Figure 5 In some embodiments, the experimental detection device for condensate water flushing wall-attached aerosol of the application further comprises a support 5 and an angle adjusting mechanism 6, the support 5 being arranged in the experimental chamber 10 of the simulation box 1, and the simulation plate body 4 being movably connected to the support 5 and being at least partially free and swingable up and down relative to the support 5.

[0042] The angle adjusting mechanism 6 is arranged between the support 5 and the simulation plate body 4, and is used to manually or automatically adjust the height of the free end of the simulation plate body 4 relative to the support 5, so as to change the preset inclination angle of the simulation plate body 4, and simulate the plane with different inclination angles in the reactor containment.

[0043] The application changes the height of the free end of the simulation plate body 4 relative to the support 5 through the angle adjusting mechanism 6, thereby changing the inclination angle of the simulation plate body 4, achieving the adjustment control of the inclination angle of the condensing panel 40, so that the condensing panel 40 on the simulation plate body 4 can be set according to different preset inclination angles, to simulate the plane with different inclination angles in the reactor containment, and the settlement aerosol steam condensate flushing simulation experiment of multiple inclined planes can be carried out.

[0044] Please refer to Figure 5 In a specific embodiment, the support 5 is provided as a frame structure for supporting the simulation plate body 4, and one end of the simulation plate body 4 in the length direction is movably connected to the support 5 through a hinged structure (not shown in the figure), so that the other end of the simulation plate body 4 can swing up and down relative to the support 5 with the pivot of the hinged structure as the center of rotation, constituting the free end of the simulation plate body 4, thereby changing the inclination angle of the condensing panel 40 through the adjustment of the height of the free end.

[0045] The angle adjusting mechanism 6 includes a plurality of fixed holes 61 arranged horizontally and linearly along the length direction on the support 5, and a support rod 62 movably hinged at one end to the simulation plate body 4, and the other end of the support rod 62 can be manually inserted and fixed in any one of the fixed holes 61 as needed, thereby supporting and fixing the simulation plate body 4 through the support rod 62 and controlling the inclination angle of the condensing panel 40.

[0046] As a preferred, in order to ensure the stability and reliability of the simulation plate body 4 supported and fixed on the support 5, the fixed holes 61 are symmetrically arranged on both sides of the support 5, and the support rods 62 are symmetrically arranged on both sides of the simulation plate body 4.

[0047] In other embodiments, the angle adjusting mechanism 6 can also be provided as an automatic angle adjusting mechanism 6 like a telescopic cylinder, and the bottom of the cylinder body of the telescopic cylinder is preferably movably hinged to the support 5, and the top of the telescopic rod of the telescopic cylinder is preferably movably hinged to the simulation plate body 4, thereby changing the inclination angle of the simulation plate body 4 through the telescopic mode of driving the telescopic rod of the telescopic cylinder.

[0048] As a preferred, the condensing panel 40 on the simulation plate body 4 can be fixed at inclination angles of 0°, 2°, 30°, 60°, 90°, etc. under the limitation of the angle adjusting mechanism 6, thereby simulating the horizontal plane, the slope plane, and the vertical plane, etc. in the reactor containment.

[0049] In some embodiments, the condensing panel 40 is detachably connected to the simulation plate body 4, and the condensing panel 40 of different simulation plate bodies 4 is provided with different surface smoothness, or the condensing panel 40 of different simulation plate bodies 4 is provided with different surface materials or surface coatings.

[0050] Alternatively, the condensing panel 40 is integrally formed on the surface of the simulation plate body 4, and the condensing panel 40 of different simulation plate bodies 4 is provided with different surface smoothness, or the condensing panel 40 of different simulation plate bodies 4 is provided with different surface materials or surface coatings.

[0051] It can be understood that when the condensing panel 40 is detachably connected to the simulation plate body 4, the surface smoothness of the test area of the simulation plate body 4 where aerosols are attached or the surface material or surface coating of the test area of the simulation plate body 4 where aerosols are attached can be changed by replacing the condensing panel 40, so as to simulate the plane with different smoothness, different surface materials or different surface coatings in the reactor containment vessel. In addition, only replacing the condensing panel 40 does not need to disassemble the simulation plate body 4, and the operation is more convenient.

[0052] When the condensing panel 40 is integrally formed on the surface of the simulation plate body 4, the surface smoothness of the test area of the simulation plate body 4 where aerosols are attached or the surface material or surface coating of the test area of the simulation plate body 4 where aerosols are attached can be changed by replacing the simulation plate body 4, so as to simulate the plane with different smoothness, different surface materials or different surface coatings in the reactor containment vessel. Although the overall replacement of the simulation plate body 4 is relatively complex in operation, it can effectively reduce the complexity of the structure of the simulation plate body 4, and facilitate the production and manufacture of the simulation plate body 4.

[0053] When the condensing panel 40 is detachably connected to the simulation plate body 4, it is necessary to ensure that the condensing panel 40 can fully exchange heat with the heat exchange medium flowing in the simulation plate body 4 after installation, so as to ensure the condensing effect of the condensing panel 40 on the steam.

[0054] The condensing panel 40 can change the surface roughness by polishing, or change the surface material or coating by spraying different types of paint, so as to process the surface material of the condensing panel 40 to be consistent with the actual situation of the plane in the reactor containment vessel.

[0055] In some embodiments, one type of condensing panel 40 can be a steel plate without polishing treatment except for oil removal, and another type of condensing panel 40 is sequentially subjected to sandblasting treatment and inorganic zinc-rich paint layer treatment. For the above two types of condensing panels 40, a certain roughness needs to be considered, so that the surface material of the condensing panel 40 is closer to the actual situation of the inner wall surface or the surface of the internal components of the reactor containment vessel.

[0056] Please refer to Figure 3 and Figure 4 In some embodiments, the simulation plate body 4 is configured as a hollow rectangular plate structure made of stainless steel with a certain thickness, the cavity inside the structure constitutes the medium flow chamber 41 for the heat exchange medium to flow, and the rectangular surface constitutes the condensing panel 40 integrally formed on the simulation plate body 4. The size of the condensing panel 40 is preferably set to 1000mm x 300mm, i.e. the test area of the condensing panel 40 is set to 0.3m 2 , for calculating the aerosol adhesion mass surface density.

[0057] Please refer to Figure 4 As a preferred, the cavity inside the simulation plate body 4 is uniformly divided into several independent medium flow chambers 41 along the length direction by the first partition plate 42, and a plurality of medium inlet pipes 43 are arranged on one side edge of the simulation plate body 4 and respectively connected to the medium flow chambers 41, and a plurality of medium outlet pipes 44 are arranged on the other side edge of the simulation plate body 4 and respectively connected to the medium flow chambers 41, and the medium inlet pipes 43 and the medium outlet pipes 44 are respectively located at opposite ends of the corresponding medium flow chambers 41 in the length direction of the simulation plate body 4, so as to ensure that the heat exchange medium entering through the medium inlet pipes 43 and discharged through the medium outlet pipes 44 can flow through the entire medium flow chamber 41. The design of the plurality of medium flow chambers 41 can make the heat exchange effect of the condensing panel 40 uniform, thereby bringing better cooling effect.

[0058] Further, in order to make the heat exchange medium in each medium flow chamber 41 flow with the maximum distance, a plurality of second partition plates 45 can be arranged in each medium flow chamber 41 to define the path of the heat exchange medium circulating flow, so that the heat exchange medium can fully exchange heat with the condensing panel 40, thereby bringing better cooling effect.

[0059] The heat exchange medium flowing in the simulation plate body 4 can be liquid or gas, and is preferably cooling water, which is more cost-effective.

[0060] Please refer to Figure 1 and Figure 3 In some embodiments, the experimental detection device for condensing water flushing wall-attached aerosol of the present application further comprises a heat exchange medium supply system 7 connected with the simulation plate body 4 through a heat exchange medium circulation pipeline 70, so as to circulate the heat exchange medium into the simulation plate body 4 and exchange heat with the condensing panel 40.

[0061] The heat exchange medium circulation pipeline 70 comprises a heat exchange medium output pipeline 701 and a heat exchange medium return pipeline 702. One end of the heat exchange medium output pipeline 701 is connected with the medium output end of the heat exchange medium supply system 7, and the other end of the heat exchange medium output pipeline 701 branches into several branch pipelines to pass through corresponding medium output pipe holes (not shown in the figure) provided on the wall surface of the simulation box 1 and are respectively connected with the corresponding medium inlet pipes 43 on the simulation plate body 4 through metal hoses (not shown in the figure). One end of the heat exchange medium return pipeline 702 is connected with the medium return end of the heat exchange medium supply system 7, and the other end of the heat exchange medium return pipeline 702 branches into several branch pipelines to pass through corresponding medium return pipe holes (not shown in the figure) provided on the wall surface of the simulation box 1 and are respectively connected with the corresponding medium outlet pipes 44 on the simulation plate body 4 through metal hoses (not shown in the figure).

[0062] The heat exchange medium supply system 7 preferably uses cooling water as the heat exchange medium. The low-temperature cooling water is delivered into each medium flow chamber 41 of the simulation plate body 4 through the medium inlet pipe 43 by the heat exchange medium output pipeline 701, so as to cool the condensing panel 40 by using the low-temperature cooling water, to promote the condensation of steam on the condensing panel 40 and form a liquid flow, and then to flush the aerosol adhered on the condensing panel 40 by using the liquid flow. The cooling water that is heated by heat exchange returns to the heat exchange medium supply system 7 through the medium outlet pipe 44 and the heat exchange medium return pipeline 702, so as to cool the cooling water that is heated by heat exchange by the heat exchange medium supply system 7. The low-temperature cooling water after cooling is recirculated to the simulation plate body 4, to realize the continuous cooling of the condensing panel 40.

[0063] Please refer to Figure 1 and Figure 3In some embodiments, the heat exchange medium supply system 7 comprises a water tank 71 for storing low-temperature cooling water, and a cooling device (not shown in the figure) provided on the water tank 71 for cooling the heat-exchanged and backflowing cooling water and sending it to the water tank 71 for storage. The medium output end of the water tank 71 is connected to a heat exchange medium output pipeline 701, and the main pipeline of the heat exchange medium output pipeline 701 is provided with a cooling water output pump 72 for pumping the cooling water into the simulation board body 4, a cooling water output control valve 73 for controlling the output amount of the cooling water, a cooling water flow meter 74 for detecting the output flow of the cooling water, a cooling water pressure gauge 75 for detecting the pressure of the cooling water, and a cooling water temperature meter 76 for detecting the output temperature of the cooling water; the medium backflow end of the cooling device is connected to a heat exchange medium backflow pipeline 702, and the main pipeline of the heat exchange medium backflow pipeline 702 is provided with a cooling water backflow control valve 77 for controlling the backflow amount of the cooling water. During the simulation experiment, the opening degrees of the cooling water output control valve 73 and the cooling water backflow control valve 77 and the power of the cooling water output pump 72 can be adjusted adaptively according to the corresponding parameter values of the cooling water fed back by the cooling water flow meter 74, the cooling water pressure gauge 75, and the cooling water temperature meter 76, so as to control the amount of the cooling water output by the heat exchange medium supply system 7 into the simulation board body 4, maintain the surface temperature of the condensing panel 40 constant, and further control the condensation rate of the steam on the condensing panel 40 constant, so that the steam is condensed into a liquid flow on the condensing panel 40 at a constant condensation rate and washes the aerosol adhered to the surface of the condensing panel 40.

[0064] Please refer to Figure 1 , Figure 3 and Figure 5 In some embodiments, the experimental detection device for condensing water washing wall-adhered aerosol of the present application further comprises a liquid collecting device 8 provided at the low-position end of the simulation board body 4 in the direction of gravity and having a collecting groove 811 connected to the condensing panel 40, so as to collect the washing liquid mixed with the aerosol condensed and flowed down from the surface of the condensing panel 40 through the collecting groove 811.

[0065] Preferably, the liquid collecting device 8 comprises a liquid collecting member 81, a liquid collecting pipeline 82, and a liquid collecting container 83. The liquid collecting member 81 is connected to the low-position end of the simulation board body 4 in the direction of gravity by a flexible metal material, and the collecting groove 811 is provided on the liquid collecting member 81 and connected to the condensing panel 40 without any obstacle, so as to collect the washing liquid flowed down from the condensing panel 40 through the collecting groove 811. One end of the liquid collecting pipeline 82 is connected to the low-position end of the liquid collecting member 81 in the direction of gravity, the other end extends to the liquid collecting container 83 through the liquid collecting pipe hole 17 provided on the wall of the simulation box body 1, and the liquid collecting pipeline 82 is connected to the collecting groove 811, so as to guide all the washing liquid collected in the collecting groove 811 into the liquid collecting container 83. In addition, a liquid discharge control valve 84 (such as a solenoid valve) is provided on the part of the liquid collecting pipeline 82 extending out of the simulation box body 1, so as to control the discharge of the washing liquid.Figure 1 The collection groove 811 is connected with a liquid collecting container 83 through a liquid collecting pipe 82, and a liquid discharge control valve 84 is arranged between the collection groove 811 and the liquid collecting container 83, so that the flushing liquid in the collection groove 811 is discharged to the liquid collecting container 83 through the liquid discharge control valve 84, facilitating the periodic sampling operation.

[0066] The flexible metal material is used to connect the liquid collecting member 81 and the simulation board body 4, so that when the simulation board body 4 is arranged at any preset inclination angle, the angle of the liquid collecting member 81 relative to the simulation board body 4 can be adjusted through the flexible metal material, and the collection groove 811 and the liquid collecting pipe 82 can always be at the lowest point of the simulation board body 4 in the direction of gravity, so that all the flushing liquid on the condensation panel 40 can be collected.

[0067] Preferably, the liquid collecting member 81 is connected to one end of the movable connection support 5 of the simulation board body 4, and after the free end of the simulation board body 4 is lifted upward and positioned at a certain height under the limitation of the angle adjusting mechanism 6, the liquid flow formed by the condensation of steam on the condensation panel 40 can flow downward under the action of gravity and flush the aerosol attached to the condensation panel 40, so that the flushing liquid mixed with the aerosol can be collected by the collection groove 811 of the liquid collecting member 81. The liquid collecting container 83 can be a beaker or other container capable of completely collecting the flushing liquid, which is not limited in the present application.

[0068] Please refer to Figure 3 and Figure 5 In some embodiments, the simulation board body 4 is provided with a fence 46 surrounding the periphery of the condensation panel 40, and an opening is arranged at one end of the fence 46 facing the collection groove 811, so as to guide the flushing liquid on the condensation panel 40 to the collection groove 811. The height of the fence 46 is preferably 2 cm, which can prevent the aerosol attached to the condensation panel 40 from flowing out of the edge of the condensation panel 40 with the flushing liquid during the flushing and re-migration process of the condensation liquid, so as to ensure that the collection device can completely collect the aerosol flushing liquid during the experiment, and ensure the accuracy of the flushing liquid detection result.

[0069] In another aspect of the present application, an experimental detection method for condensate flushing wall-attached aerosol is provided, which is applied to any one of the experimental detection devices for condensate flushing wall-attached aerosol described above, and the method comprises the following steps:

[0070] S100, the operating personnel enter the experiment chamber 10 through the manhole, adjust the simulation board body 4 at a preset inclination angle, so as to simulate a plane with a specific inclination angle in the containment vessel of the reactor through the condensation panel 40; the personnel withdraw and close the manhole cover and the pressure relief valve 16, maintain the airtight state of the simulation box 1, and then start the aerosol supply system 3 to supply the aerosol into the experiment chamber 10 according to the set supply time.

[0071] S200, after the aerosol is completely introduced, the aerosol supply system 3 is closed, personnel enter and clean the aerosol in the non-experimental area of the simulation box 1, only the aerosol attached to the condensation panel 40 is reserved, so as to simulate the situation of the radioactive aerosol attached on the plane with a specific inclination angle in the reactor containment after an accident occurs. The non-experimental area here refers to all areas except the experimental area where the condensation panel 40 is attached and the aerosol is settled, including the enclosure 46 around the periphery of the condensation panel 40.

[0072] S300, after the personnel are withdrawn, the steam supply system 2 and the heat exchange medium supply system 7 are started, steam is introduced into the experimental cavity 10, and cooling water is introduced into each medium flow chamber 41 of the simulation panel 4, so as to cool the condensation panel 40 by the low-temperature cooling water, promote the condensation of the steam on the surface of the condensation panel 40 and form a liquid flow, and then flush the aerosol attached to the condensation panel 40 by the liquid flow, so as to simulate the process of the aerosol being flushed and re-migrated by the steam condensate after being attached on the plane in the reactor containment.

[0073] S400, according to the preset time interval, the flushing liquid mixed with the aerosol condensed and flowed down from the surface of the condensation panel 40 is collected in batches by the liquid collecting device 8, when the turbidity of the flushing liquid collected at the last time approaches that of clean water, the steam is stopped, the simulation box 1 is continuously cooled by the heat exchange medium supply system 7, and one simulation experiment is completed. The flushing liquid should be collected by periodically replacing different liquid collecting containers 83 in each preset time period, and good labeling should be done.

[0074] S500, after cooling to room temperature, personnel enter to collect and weigh the remaining aerosol on the surface of the condensation panel 40 which is not flushed away, the aerosol remaining mass is obtained by drying and weighing; the aerosol in the flushing liquid collected in each preset time period is separated by using a filter system combined with an aluminum membrane water system, the aerosol flushing mass in each preset time period is determined by drying and weighing, and the total aerosol attachment mass is obtained; the volume of the condensate in each preset time period is weighed by a measuring cylinder, so as to determine the steam condensation amount in each preset time period. According to the weighing results, the attachment density of the aerosol in this simulation experiment, the aerosol flushing rate in different preset time periods, and the change rule of the aerosol flushing rate with time in this simulation experiment are calculated.

[0075] The preset time is equal to the sum of the time for the previous liquid collecting container 83 to be removed and the time for the next liquid collecting container 83 to be placed into the sampling station (i.e. below the liquid outlet end of the liquid collecting pipeline 82) and the preset sampling time interval. According to the weighing result, the aerosol flushing rate per unit time corresponding to each collection time can be calculated, i.e. the aerosol flushing rate, and the variation law of the aerosol flushing rate with time can be obtained. According to the weighing of each liquid collecting container 83, the preset time and the preset sampling time interval, the variation law of the aerosol flushing percentage with time can be obtained.

[0076] The aerosol supply system 3 of the present application supplies aerosol to the experimental cavity 10 of the simulation box 1 to simulate the source term environment under a severe accident. The condensation panel 40 of the simulation plate body 4 simulates the inner wall surface of the containment of a nuclear power plant and the surface of the equipment inside the containment with aerosol adhered and settled thereon. The steam supply system 2 supplies steam to the experimental cavity 10 of the simulation box 1 to maintain the stable steam environment inside the simulation box 1. The heat exchange medium supply system 7 cooperates with the steam supply system 2 to maintain the surface temperature of the condensation panel 40 and thus control the steam condensation rate. The liquid collecting device 8 collects the aerosol condensation flushing liquid on the condensation panel 40 to simulate the wall flushing of the aerosol adhered to the plane by the steam condensate inside the containment.

[0077] The present application is used to study the aerosol flushing behavior of steam condensation on the condensation panel 40 with aerosol adhered thereon, and thus the aerosol needs to be uniformly adhered and settled on the condensation panel 40 before the experiment. Before the experiment starts, the simulation plate body 4 is first installed in the support 5 in the experimental cavity 10 through the manhole, the inclination angle of the simulation plate body 4 is defined by the support rod 62 and the fixing hole 61 at a suitable position, the liquid collecting pipeline 82 of the liquid collecting device 8 is connected to the liquid collecting member 81, the collection groove 811 of the liquid collecting member 81 is sealed by using the embossed paper to prevent the aerosol from leaking to the atmosphere through the liquid collecting member 81 and the liquid collecting pipeline 82 during the aerosol introduction process. After all the preparations are completed, the manhole cover and the pressure relief valve 16 are closed, the aerosol supply system 3 is started to introduce the aerosol and make it settle. After the aerosol settling stage is completed, the personnel enter the experimental cavity 10 and clean the aerosol in the non-experimental area, and then remove the embossed paper sealing the collection groove 811 of the liquid collecting member 81. After all the cleaning work is completed, the personnel leave, the manhole cover is closed, and the steam condensation aerosol flushing experiment starts.

[0078] Since there is a certain difference in the aerosol deposition mass density and uniformity of different wall areas after a severe accident of the reactor, in order to determine the aerosol deposition surface density on the condensing panel 40, the aerosol deposited on the condensing panel 40 needs to be collected in the experiment process, filtered and weighed, so as to obtain the aerosol deposition average density in the experiment process. In order to determine the aerosol deposition uniformity on the condensing panel 40, a pre-experiment needs to be carried out to determine the aerosol deposition distribution rule. Preferably, a thin magnet can be used to adsorb the measurement sample on the condensing panel 40. The measurement sample is arranged in a total of 15 and uniformly spaced. After the pre-experiment of aerosol deposition is completed, the measurement sample is taken out, the aerosol deposition mass surface density of the area is calculated according to the deposition mass and the sample area, the distribution rule and the uniformity of the aerosol deposition are determined, and thus the aerosol supply time length in the experiment process can be determined according to the pre-experiment result.

[0079] In some embodiments, the method of the present application further comprises: S600, changing the preset inclination angle of the simulation board body 4, or / and changing the surface smoothness of the condensing panel 40, or / and changing the surface material or surface coating of the condensing panel 40, and then performing the operations of S100 to S500.

[0080] It can be understood that in the secondary test, only the preset inclination angle of the simulation board body 4 can be changed without changing the type of the condensing panel, or the preset inclination angle of the simulation board body 4 and the type of the condensing panel can be changed at the same time, or the preset inclination angle of the simulation board body 4 can be changed without changing the type of the simulation board body, and the simulation board body can be adjusted according to the experimental detection requirements.

[0081] The present application can realize simulation experiments under different working conditions through multiple experiments. After one aerosol flushing simulation experiment under different steam condensation rates is completed for each type of condensing panel 40, different types of condensing panels 40 are replaced, so that all the condensing panels 40 with different inclination angles, different aerosol types and different aerosol deposition mass surface densities can perform the aerosol flushing simulation experiment, and the influence of different inclination angles, different aerosol types, different aerosol deposition mass surface densities, different simulation board body 4 types and different steam condensation rates on the aerosol flushing rate can be obtained.

[0082] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent flow conversion using the content of the specification and the drawings, or direct or indirect application in other related technical fields, is also included in the patent protection scope of the present application.

Claims

1. An experimental test device for condensate water flush wall-attached aerosol, characterized in that, The simulation box (1) comprises: An experimental cavity (10) for simulating the internal environment of a reactor containment vessel; A steam supply system (2) connected to the experimental cavity (10) through a steam output pipeline (20) to supply steam into the experimental cavity (10); An aerosol supply system (3) connected to the experimental cavity (10) through an aerosol output pipeline (30) to supply aerosol into the experimental cavity (10); A simulation plate body (4) arranged in the experimental cavity (10) at a preset inclination angle, and internally flowing with a heat exchange medium, and having a condensing panel (40) on the surface, the condensing panel (40) exchanges heat with the heat exchange medium, so that the steam in the experimental cavity (10) condenses on the surface of the condensing panel (40) and flushes the aerosol attached to the condensing panel (40); The condensing panel (40) is detachably connected to the simulation plate body (4), and the surfaces of different condensing panels (40) are arranged to have different smoothness, or different condensing panels (40) are arranged to have different surface materials or surface coatings; Alternatively, the condensing panel (40) is integrally formed on the simulation plate body (4), and the surfaces of the condensing panels (40) of different simulation plate bodies (4) are arranged to have different smoothness, or the condensing panels (40) of different simulation plate bodies (4) are arranged to have different surface materials or surface coatings; Further comprising a liquid collecting device (8) arranged at the low end of the simulation plate body (4) in the direction of gravity and having a collection groove (811) connected to the condensing panel (40) to collect the flushing liquid mixed with the aerosol condensed on the surface of the condensing panel (40) and flowing down.

2. The apparatus of claim 1, wherein, Further comprising: A support (5) arranged in the experimental cavity (10), the simulation plate body (4) is movably connected to the support (5) and at least partially free and swings up and down relative to the support (5); An angle adjusting mechanism (6) arranged between the support (5) and the simulation plate body (4) to manually or automatically adjust the height of the free end of the simulation plate body (4) relative to the support (5), thereby changing the preset inclination angle of the simulation plate body (4) to simulate different inclination angles of the plane in the reactor containment vessel.

3. The apparatus of claim 1, wherein, The simulation box (1) is provided with a heat preservation structure (13) for preventing heat exchange between the experimental cavity (10) and the outside space, and a heating structure (14) for heating at least part of the experimental cavity (10), and the heating structure (14) is away from the simulation plate body (4).

4. The apparatus of claim 1, wherein, The simulation box (1) is provided with a pressure relief pipeline (15) connecting the experimental cavity (10) with the outside space, and the pressure relief pipeline (15) is provided with a pressure relief valve (16).

5. The apparatus of any one of claims 1-4, wherein the apparatus is configured to perform the test by: Further comprising a heat exchange medium supply system (7) connected to the simulation plate body (4) through a heat exchange medium circulation pipeline (70) to circulate the heat exchange medium into the simulation plate body (4) and exchange heat with the condensing panel (40).

6. The experimental test device for condensation water flush wall-adhering aerosol according to claim 5, characterized in that, The simulation plate body (4) is provided with a fence (46) surrounding the periphery of the condensation panel (40), and the fence (46) is provided with an opening at one end facing the collection groove (811) to guide the irrigation liquid on the condensation panel (40) to the collection groove (811).

7. A method for experimental detection of a condensation water flush wall-attached aerosol, characterized by The experimental detection device for condensate irrigation wall-attached aerosol according to any one of claims 1-6 comprises the following steps: S100, the simulation plate body (4) is set at a preset inclination angle to simulate a plane with a specific inclination angle in the containment vessel by the condensation panel (40); the closed state of the simulation box (1) is maintained, and aerosol is introduced into the experimental cavity (10) according to the set introduction time; S200, after the aerosol is introduced, the aerosol in the non-experimental area of the experimental cavity (10) is cleaned, and only the aerosol attached to the condensation panel (40) is retained to simulate the attachment of radioactive aerosol on the plane in the containment vessel after an accident occurs; S300, steam is introduced into the experimental cavity (10), and a heat exchange medium is introduced into the simulation plate body (4) to cool the condensation panel (40), so that the steam condenses on the surface of the condensation panel (40) and forms a liquid flow, and then the aerosol attached to the condensation panel (40) is washed by the liquid flow to simulate the washing and re-migration process of the aerosol after being attached to the plane in the containment vessel; S400, the irrigation liquid mixed with aerosol condensed and flowed down from the surface of the condensation panel (40) is collected in batches according to a preset time interval, the steam is stopped when the turbidity of the last collected irrigation liquid approaches that of water, and one simulation experiment is completed; S500, the remaining aerosol on the surface of the condensation panel (40) which is not washed off is collected and weighed to obtain the residual mass of the aerosol; the aerosol and condensate in the irrigation liquid collected in each preset time period are separated and weighed to obtain the aerosol washing mass and the condensate volume in each preset time period; the attachment density of the aerosol in this simulation experiment, the aerosol washing rate in different preset time periods, and the change rule of the aerosol washing rate with time in this simulation experiment are calculated according to the weighing results.

8. The method of claim 7, wherein the method is used to test a condensate- flushed wall-flow aerosol. Further comprising: S600, change the preset inclination angle of the simulation plate body (4), or / and change the surface smoothness of the condensation panel (40), or / and change the surface material or surface coating of the condensation panel (40), and then perform the operations of S100 to S500.

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