Fuel cladding performance test method under simulated reactivity introduction accident conditions

Abstract

The present invention proposes a method for testing the performance of fuel cladding under a simulated reactivity introduction accident condition, the method comprising: heating the simulated fuel rods and increasing the temperature and pressure of the loop water in the primary loop water environment of the pressurized water reactor under a simulated condition when the simulated fuel rods are used, and measuring the temperature rise curves of multiple areas of the fuel cladding tubes; after cooling and reducing the pressure of the loop water to a preset temperature and pressure, performing chemical composition and microstructure analysis on a small section sample axially cut from the simulated fuel rods, so as to construct a fuel cladding tube performance test report based on the surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tubes in different temperature zones, and determine the performance of the fuel cladding tubes under the reactivity introduction accident condition, thereby, based on the influence of rapid heating on the microstructure and chemical composition distribution of the fuel cladding tubes, the performance test report constructed accurately evaluates the performance characteristics of the fuel cladding tubes under the reactivity introduction accident condition.

Description

Technical Field

[0001] The invention relates to the technical field of fuel assembly performance testing, and in particular to a method for testing fuel cladding performance under simulated reactivity introduction accident conditions. Background Art

[0002] Reactivity-insertion accident (RIA) generally refers to the ejection of control rods in a reactor. It is a design basis accident that must be considered during reactor design and construction. The enthalpy threshold of RIA failure in fuel cladding tubes will significantly decrease with the increase of fuel consumption, resulting in damage to fuel assemblies. The safety risks brought about by the decrease in enthalpy threshold must be considered. Rapid temperature rise inside the fuel cladding tube is one of the main characteristics of RIA, which has an important impact on the failure mode of the fuel cladding tube. Among the related technologies, the research foundation of RIA is very weak, and there is a lack of relevant test facilities and test methods for fuel cladding tube performance testing under simulated reactivity introduction accident conditions. Therefore, it is very necessary to conduct experimental research on the RIA performance of fuel cladding tube materials and establish relevant test methods. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, the first purpose of the present invention is to propose a fuel cladding performance testing method under simulated reactive introduction accident conditions, based on the influence of rapid heating on the microstructure and chemical composition distribution of the fuel cladding tube, to construct a performance test report to accurately evaluate the performance characteristics of the fuel cladding tube under reactive introduction accident conditions.

[0005] The second object of the present invention is to provide a fuel cladding performance testing device under simulated reactivity introduction accident conditions.

[0006] A third objective of the present invention is to provide an electronic device.

[0007] A fourth object of the present invention is to provide a non-transitory computer-readable storage medium storing computer instructions.

[0008] To achieve the above-mentioned purpose, the first embodiment of the present invention provides a method for testing the performance of fuel cladding under a simulated reactivity introduction accident condition, the method comprising:

[0009] Construct the simulated working conditions when the simulated fuel rods are used in the primary water environment of a pressurized water reactor;

[0010] Under the simulated working conditions, by heating the simulated fuel rods and increasing the temperature and pressure of the loop water in the primary loop water environment of the pressurized water reactor, the temperature rise curves of multiple areas of the fuel cladding tube corresponding to the simulated fuel rods are measured;

[0011] After cooling and reducing the pressure of the loop water to a preset temperature and pressure, taking out the simulated fuel rod, and cutting the simulated fuel rod axially into a preset number of small section specimens;

[0012] Performing chemical composition and microstructure analysis on each of the small sample sections to obtain surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tube in different temperature zones;

[0013] Based on the surface chemical composition state change characteristics and surface profile structure data in different temperature zones, a fuel cladding tube performance test report is constructed, and based on the fuel cladding tube performance test report, the fuel cladding tube performance under the reactivity introduction accident condition is determined.

[0014] To achieve the above-mentioned purpose, the second embodiment of the present invention provides a fuel cladding performance test device under a simulated reactivity introduction accident condition, the device comprising:

[0015] A construction module is used to construct a simulation condition when the fuel rod is used in the primary water environment of a pressurized water reactor;

[0016] A measuring module is used to measure the temperature rise curves of multiple regions of the fuel cladding tube corresponding to the simulated fuel rod by heating the simulated fuel rod and increasing the temperature and pressure of the loop water of the primary loop water environment of the pressurized water reactor under the simulated working condition;

[0017] A cooling module, used for cooling and reducing the pressure of the loop water to a preset temperature and pressure, taking out the simulated fuel rod, and cutting the simulated fuel rod axially into a preset number of small sections;

[0018] An analysis module is used to perform chemical composition and microstructure analysis on each of the small sample sections to obtain surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tubes in different temperature zones;

[0019] The determination module is used to construct a fuel cladding tube performance test report based on the surface chemical composition state change characteristics and surface profile structure data in different temperature zones, and determine the fuel cladding tube performance under the reactivity introduction accident condition based on the fuel cladding tube performance test report.

[0020] The fuel cladding performance testing method, device, electronic equipment and storage medium of the embodiment of the present invention under the simulated reactivity introduction accident condition heat the simulated fuel rod and increase the temperature and pressure of the loop water in the primary loop water environment of the pressurized water reactor under the simulated condition when the simulated fuel rod is used, and measure the temperature rise curves of multiple areas of the fuel cladding tube; after the loop water is cooled and the pressure is reduced to the preset temperature and pressure, the chemical composition and microstructure of the small section sample cut axially of the simulated fuel rod are analyzed, so as to construct a fuel cladding tube performance test report based on the surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tube in different temperature zones, and determine the performance of the fuel cladding tube under the reactivity introduction accident condition. Therefore, based on the influence of rapid heating on the microstructure and chemical composition distribution of the fuel cladding tube, the performance test report constructed accurately evaluates the performance characteristics of the fuel cladding tube under the reactivity introduction accident condition.

[0021] To achieve the above-mentioned purpose, the third aspect of the present invention proposes an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the method described in the first aspect.

[0022] In order to achieve the above-mentioned purpose, the fourth aspect of the present invention proposes a non-transitory computer-readable storage medium storing computer instructions, where the computer instructions are used to enable the computer to execute the method described in the first aspect.

[0023] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0025] Figure 1 A schematic flow chart of a method for testing fuel cladding performance under a simulated reactivity introduction accident condition provided by an embodiment of the present invention;

[0026] Figure 2 An implementation example diagram of a fuel cladding performance testing method under a simulated reactivity introduction accident condition provided by an embodiment of the present invention;

[0027] Figure 3 A schematic structural diagram of a fuel cladding performance testing device under simulated reactivity introduction accident conditions provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0029] It should be noted that the acquisition, storage, use, and processing of data in the technical solution of this application comply with the relevant provisions of relevant laws and regulations.

[0030] The following describes a method and apparatus for testing fuel cladding performance under simulated reactivity introduction accident conditions according to an embodiment of the present invention with reference to the accompanying drawings.

[0031] Figure 1 A schematic flow chart of a method for testing fuel cladding performance under simulated reactivity introduction accident conditions provided by an embodiment of the present invention.

[0032] like Figure 1 As shown, the method comprises the following steps:

[0033] Step 101, constructing a simulated operating condition when a simulated fuel rod is used in a primary loop water environment of a pressurized water reactor.

[0034] Optionally, the simulated fuel rod may be an electrically heated simulated fuel rod.

[0035] In some embodiments, the heating element simulating the fuel rod is a high-temperature alloy thin-walled tube, the outer wall of the high-temperature alloy thin-walled tube is a spiral wire groove, and a solid ceramic corundum rod is installed inside the high-temperature alloy thin-walled tube, and the outer side of the ceramic corundum rod is the fuel cladding tube. Therefore, the heating element material is a high-temperature alloy thin-walled tube. Compared with the rod-shaped material, the cross-sectional area of ​​the high-temperature alloy thin-walled tubular material is small, which improves the heating resistance and has high heating efficiency. Compared with the filamentary material, the tubular material is not easy to burn out under high temperature conditions and has better mechanical properties.

[0036] Optionally, the fuel cladding tube fits tightly to the heating rod for heating without ceramic insulating material in between.

[0037] Among them, laser cutting method can be used to cut spiral grooves along the outer wall of the heating element. The function of the grooves is to increase the length of the heating zone and the resistance of the heating zone without increasing the cross-sectional area, so that the heat of the heating rod is concentrated in the spiral cutting area.

[0038] Optionally, a solid ceramic corundum rod is installed inside the heating element. The ceramic material can maintain good mechanical strength at high temperatures, thereby preventing the heating element from collapsing at high temperatures.

[0039] Optionally, there is no electrical insulation between the fuel cladding and the metal heating rod, so as to greatly increase the heating speed of the fuel cladding.

[0040] In some embodiments, an implementation method for constructing a simulated operating condition when a simulated fuel rod is used in a pressurized water reactor primary water environment can be: establishing a pressurized water reactor primary water environment through a high-temperature and high-pressure dynamic circulating water environment and a pressurized cooling water system; controlling the chemical parameters and loop water pressure of the loop water by an upward filling and downward discharge method, and controlling the water quality of the loop water by a water chemical control loop, to establish a simulated operating condition when a simulated fuel rod is used in a pressurized water reactor primary water environment.

[0041] Optionally, a high-temperature and high-pressure dynamic circulating water environment can be established by using a shielded high-pressure magnetic circulating pump as the main circulating pump and a jacketed cooling section to remove the heat generated by the test section in the loop water, so that the temperature of the fluid entering the main circulating pump is slightly lower than the required inlet temperature of the test section.

[0042] The cooling section is cooled by a pressurized cooling water system to ensure that the cooling water does not boil in the cooling section. The loop water is heated by a heating rod to establish a primary loop water environment for a pressurized water reactor. Furthermore, a shielded high-pressure magnetic circulation pump can be used as the main circulation pump with a flow rate of 0 to 3 m 3 / h, frequency conversion control. Jacketed cooling section, the inner pipe of the flow channel can be DN50, the outer pipe can be DN100, the cooling capacity is about ≥50kW, the heat generated by the test section in the loop water is taken away, so that the temperature of the fluid entering the main circulation pump is slightly lower than the inlet temperature required by the test section; the cooling section material can be 316L stainless steel. The cooling section is cooled by a pressurized cooling water system to ensure that the cooling water does not boil in the cooling section. The pressurized cooling water system is cooled by a refrigeration unit to ensure that the temperature of the cooling water is controlled within the set temperature ±1℃.

[0043] Optionally, the water chemistry control loop is composed of a conductivity meter, a pH meter, a dissolved oxygen meter, a high-pressure back-pressure valve, a low-pressure back-pressure valve, a resin tank, a high-pressure metering pump, etc. The water chemistry control loop can measure and control parameters such as dissolved oxygen, pH value, and conductivity in the water chemistry medium.

[0044] Specifically, the water flow rate can be controlled to 8-10m / s, which is equivalent to the flow rate of the primary water environment of a nuclear power plant, and meets the test requirements under high-temperature and high-pressure dynamic water environment conditions; the oxygen control of the water chemistry control loop usually adopts the inert gas bubbling method, and can also be deoxygenated by adding amine. A gas mass flow meter is used to control the amount of dissolved gas in the water, and the minimum dissolved oxygen content can be controlled to be less than 2ppb. The water chemistry control loop is equipped with an online dosing device, which can realize the online addition of boric acid, lithium hydroxide, etc., and the pH value of the solution can be measured and controlled online.

[0045] Among them, the water chemistry control loop uses nuclear-grade cationic resin and nuclear-grade mixed bed resin purification methods to remove all remaining impurities in the water. Cationic resin is used to filter cations such as Fe and Mo in the test loop, and is used for Li-containing water through Li saturation. Mixed bed resin can treat water containing B and Li through B and Li saturation. Three parameters of dissolved oxygen, pH value and conductivity are controlled to ensure stable water quality. By increasing the upstream and downstream flow rates, the water chemistry parameters of the test water chemistry control loop are stabilized, and the water update frequency in the water chemistry control loop is greater than or equal to 5 times.

[0046] Optionally, the loop water pressure is controlled by a high-precision back pressure valve installed on the water chemistry control loop panel in the downflow channel. The control accuracy can be within ±0.2MPa of the set value. The upflow is manually controlled by a high-pressure metering pump and mechanically adjusted to ensure the stability of the upflow; the downflow is automatically controlled by the back pressure valve according to the set pressure and the upflow of the high-pressure metering pump, and the balance is maintained. The upflow and downflow are preheated through the regenerative heat exchanger and injected into the loop water, with a flow rate of 120L / h, which can ensure that the loop water is replaced more than twice per hour to simulate the environmental conditions of the primary loop water of the pressurized water reactor.

[0047] In addition, an in-tube pressurizing device is also needed to ensure that the pressure inside the fuel cladding tube can be measured and controlled, so as to better construct simulated working conditions. The in-tube pressurizing device is composed of a high-pressure gas cylinder, pipelines, pressure gauges, regulating valves, pressure sensors, etc. The pipeline is a thin stainless steel tube connected to an external gas pressurization circuit to achieve measurable and controllable pressure inside the fuel cladding tube.

[0048] Among them, the pressure inside the fuel cladding tube can be further measured and controlled through the seal. The copper linings of the positive electrode seal and the negative electrode seal fit tightly with the fuel cladding tube, which can not only seal the internal gas, but also make direct electrical contact with the fuel cladding tube, so that the fuel cladding tube and the heating rod can be heated synchronously.

[0049] Optionally, in order to avoid the influence of high-temperature and high-pressure flowing water on the heating of the fuel cladding tube and ensure the reliability of rapid heating of the fuel cladding tube, an in-kettle flow guide device is also designed, wherein the in-kettle flow guide device can be a metal flow guide tube, specifically, a part of the high-temperature water enters the metal flow guide tube from the small hole outside the metal flow guide tube. The metal flow guide tube has a small area and a very stable water flow state, which is conducive to the rapid heating test of the fuel cladding tube.

[0050] Another part of the high-temperature water can be blocked by the water baffle, flowing into the gap between the metal guide pipe and the autoclave through the outside of the water baffle, and then flowing out of the autoclave through the outside of the upper water baffle. The existence of the upper and lower water baffles greatly weakens the convection effect of water.

[0051] Optionally, the fuel cladding tube is located inside the metal flow guide tube to avoid interference from water in the autoclave.

[0052] Among them, circulating cooling water devices are set at the upper and lower ports of the autoclave to ensure that during the rapid heating process, there will be no high-temperature and high-pressure water leakage accidents due to high-temperature failure of the seal; at the bottom of the autoclave, a larger metal seal is used, and a circle of small holes is set on the edge of the metal seal to increase the cooling effect and improve the safety of the test.

[0053] Step 102, under simulated working conditions, by heating the simulated fuel rods and increasing the temperature and pressure of the loop water in the primary loop water environment of the PWR, the temperature rise curves of multiple regions of the fuel cladding tube corresponding to the simulated fuel rods are measured.

[0054] In some embodiments, four groups of thermocouples (composed of NiCr wires and NiSi wires) may be used to measure the temperature of four different regions of the fuel cladding tube respectively to obtain temperature rise curves of the four regions.

[0055] Optionally, a grooved metal cover can be used to compact and fix the four sets of thermocouples to prevent them from falling off. The thermocouple wires are sheathed in an insulating hose and then in a ceramic alumina tube for double electrical insulation protection to avoid interference, thus achieving real-time measurement of the transient temperature of the fuel cladding tube in a high-temperature and high-pressure water environment.

[0056] Optionally, a high-power power supply can be used to carry out a rapid temperature rise test on the simulated fuel rod. The heating adopts a low-voltage and high-current method. The fuel cladding tube and the internal heating element are energized and heated synchronously. The surface temperature of the fuel cladding tube rises instantly, and four sets of thermocouples are used to measure the temperature rise curve of the fuel cladding tube.

[0057] Step 103, after cooling and reducing the pressure of the loop water to a preset temperature and pressure, the simulated fuel rod is taken out and cut into a preset number of small sections along the axis of the simulated fuel rod.

[0058] In some embodiments, the preset temperature and pressure may be normal temperature and pressure, but are not limited thereto, and this embodiment does not make any specific limitation thereto.

[0059] Step 104 , performing chemical composition and microstructure analysis on each small section sample to obtain surface chemical composition state variation characteristics and surface profile structure data of the fuel cladding tube in different temperature zones.

[0060] In some embodiments, the chemical composition and microstructure analysis of each small section sample can be performed using a scanning electron microscope (SEM), an energy dispersive spectrometer (EDS), an X-ray diffractometer (XRD), or a transmission electron microscope (TEM) to obtain the surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tube in different temperature zones, but is not limited to this.

[0061] Step 105, constructing a fuel cladding tube performance test report based on the surface chemical composition state change characteristics and surface profile structure data in different temperature regions, and determining the fuel cladding tube performance under the reactivity introduction accident condition based on the fuel cladding tube performance test report.

[0062] In some embodiments, a fuel cladding performance test report is constructed based on the surface chemical composition state change characteristics and surface profile structure data in different temperature zones, and based on the fuel cladding performance test report, the performance of the fuel cladding under a reactivity-insertion accident (RIA) condition is determined. One implementation method may be to construct a surface chemical composition change curve based on the surface chemical composition state change characteristics in different temperature zones; construct a fuel cladding performance test report based on the surface chemical composition change curve and the surface profile structure data, and determine the performance level corresponding to the fuel cladding performance under the reactivity-insertion accident condition based on the fuel cladding performance test report.

[0063] The fuel cladding performance testing method under simulated reactivity introduction accident conditions of the embodiment of the present invention heats the simulated fuel rods and raises the temperature and pressure of the loop water in the primary loop water environment of the pressurized water reactor under simulated conditions when the simulated fuel rods are used, and measures the temperature rise curves of multiple areas of the fuel cladding tubes; after the loop water is cooled and depressurized to preset temperature and pressure, the chemical composition and microstructure of the small section sample cut axially from the simulated fuel rods are analyzed, so as to construct a fuel cladding tube performance test report based on the surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tubes in different temperature zones, and determine the performance of the fuel cladding tubes under the reactivity introduction accident conditions. Therefore, based on the influence of rapid heating on the microstructure and chemical composition distribution of the fuel cladding tubes, the performance test report constructed accurately evaluates the performance characteristics of the fuel cladding tubes under the reactivity introduction accident conditions.

[0064] In summary, in order to better understand the present invention, the present invention also proposes an implementation example diagram of a fuel cladding performance test method under a simulated reactivity introduction accident condition, as shown in FIG. Figure 2 As shown, the implementation steps of the fuel cladding performance test method under the condition of simulated reactive introduction accident can include: 1. Equipment metering and calibration used in the fuel cladding performance test method under the condition of simulated reactive introduction accident; 2. Processing and manufacturing of electrically heated simulated fuel rods; 3. Assembly of electrically heated simulated fuel rods; 4. Cleaning of test pieces (electrically heated simulated fuel rods); 5. Assembly and sealing of test sections corresponding to electrically heated simulated fuel rods; 6. Electrical connection and insulation corresponding to electrically heated simulated fuel rods; 7. Connection of gas pressurization pipelines corresponding to electrically heated simulated fuel rods; 8. Chemical configuration of loop water; 9. Deoxygenation of aqueous solution of loop water; 10. Measurement of water chemical parameters of loop water; 11. Temperature and pressure increase of loop water; 12. Rapid temperature increase test of electrically heated simulated fuel rods; 13. Online measurement of temperature rise curve; 14. Temperature and pressure reduction of loop water; 15. Removal of electrically heated simulated fuel rods; 16. Cutting of RIA fuel cladding tubes; 17. SEM and EDS measurement and characterization; 18. Chemical composition and microstructure analysis; 19. Construction of fuel cladding tube performance test report.

[0065] In order to implement the above-mentioned embodiment, the present invention also proposes a fuel cladding performance testing device under a simulated reactivity introduction accident condition.

[0066] Figure 3 A schematic structural diagram of a fuel cladding performance testing device under simulated reactivity introduction accident conditions provided in an embodiment of the present invention.

[0067] like Figure 3 As shown, the fuel cladding performance testing device 30 under simulated reactivity introduction accident conditions includes: a construction module 31, a measurement module 32, a cooling module 33, an analysis module 34, and a determination module 35.

[0068] Construction module 31 is used to construct a simulated working condition when the simulated fuel rod is used in the primary loop water environment of a pressurized water reactor;

[0069] The measuring module 32 is used to measure the temperature rise curves of multiple regions of the fuel cladding tube corresponding to the simulated fuel rod by heating the simulated fuel rod and increasing the temperature and pressure of the loop water of the primary loop water environment of the pressurized water reactor under the simulated working condition;

[0070] A cooling module 33 is used to cool and depressurize the loop water to a preset temperature and pressure, take out the simulated fuel rod, and cut the simulated fuel rod into a preset number of small sections along the axial direction of the simulated fuel rod;

[0071] An analysis module 34 is used to perform chemical composition and microstructure analysis on each of the small sample sections to obtain surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tubes in different temperature zones;

[0072] The determination module 35 is used to construct a fuel cladding tube performance test report based on the surface chemical composition state change characteristics and surface profile structure data in different temperature zones, and determine the fuel cladding tube performance under the reactivity introduction accident condition based on the fuel cladding tube performance test report.

[0073] Furthermore, in a possible implementation of an embodiment of the present invention, the heating element of the simulated fuel rod is a high-temperature alloy thin-walled tube, the outer wall of the high-temperature alloy thin-walled tube is a spiral groove, and a solid ceramic corundum rod is installed inside the high-temperature alloy thin-walled tube, and the outer side of the ceramic corundum rod is a fuel cladding tube.

[0074] Furthermore, in a possible implementation of the embodiment of the present invention, the construction module 31 is specifically used to

[0075] The primary water environment of the PWR is established through a high-temperature and high-pressure dynamic circulating water environment and a pressurized cooling water system;

[0076] The chemical parameters and pressure of the loop water are controlled by the upward filling and downward discharge method, and the water quality of the loop water is controlled by the water chemical control loop, so as to establish a simulated working condition when simulating the fuel rods used in the primary loop water environment of a pressurized water reactor.

[0077] Further, in a possible implementation manner of the embodiment of the present invention, the determining module 35 is specifically configured to:

[0078] Based on the surface chemical composition state change characteristics in different temperature zones, the surface chemical composition change curve is constructed;

[0079] A fuel cladding tube performance test report is constructed based on the surface chemical composition change curve and the surface profile structure data, and a performance level corresponding to the fuel cladding tube performance under the reactivity introduction accident condition is determined based on the fuel cladding tube performance test report.

[0080] The fuel cladding performance testing device under simulated reactivity introduction accident conditions of the embodiment of the present invention heats the simulated fuel rods and increases the temperature and pressure of the loop water in the primary loop water environment of the pressurized water reactor under simulated conditions when the simulated fuel rods are used, and measures the temperature rise curves of multiple areas of the fuel cladding tubes; after the loop water is cooled and depressurized to preset temperature and pressure, the chemical composition and microstructure of the small section sample axially cut from the simulated fuel rods are analyzed, so as to construct a fuel cladding tube performance test report based on the surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tubes in different temperature zones, and determine the performance of the fuel cladding tubes under the reactivity introduction accident conditions. Therefore, based on the influence of rapid heating on the microstructure and chemical composition distribution of the fuel cladding tubes, the performance test report constructed accurately evaluates the performance characteristics of the fuel cladding tubes under the reactivity introduction accident conditions.

[0081] In order to implement the above embodiment, the present invention further provides an electronic device, including:

[0082] at least one processor; and

[0083] a memory communicatively connected to the at least one processor; wherein,

[0084] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can perform the aforementioned method.

[0085] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0086] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0087] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0088] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute the instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0089] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0090] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0091] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0092] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for testing fuel cladding performance under simulated reactivity introduction accident conditions, characterized in that: The method comprises: Construct the simulated working conditions when the simulated fuel rods are used in the primary water environment of a pressurized water reactor; Under the simulated working conditions, by heating the simulated fuel rods and increasing the temperature and pressure of the loop water in the primary loop water environment of the pressurized water reactor, the temperature rise curves of multiple areas of the fuel cladding tube corresponding to the simulated fuel rods are measured, wherein a high-power power supply is used to carry out a temperature rise test on the simulated combustion material rods, and the heating adopts a low-voltage and high-current method. The fuel cladding tube and the internal heating element are energized and heated synchronously, and four groups of thermocouples are used to measure the temperature of four different areas of the fuel cladding tube respectively, so as to obtain the temperature rise curves of the four areas; After cooling and reducing the pressure of the loop water to a preset temperature and pressure, taking out the simulated fuel rod, and cutting the simulated fuel rod axially into a preset number of small section specimens; Performing chemical composition and microstructure analysis on each of the small sample sections to obtain surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tube in different temperature zones; Based on the surface chemical composition state change characteristics and surface profile structure data in different temperature zones, a fuel cladding tube performance test report is constructed, and based on the fuel cladding tube performance test report, the fuel cladding tube performance under the reactivity introduction accident condition is determined, including: based on the surface chemical composition state change characteristics in different temperature zones, a surface chemical composition change curve is constructed; according to the surface chemical composition change curve and the surface profile structure data, a fuel cladding tube performance test report is constructed, and based on the fuel cladding tube performance test report, a performance level corresponding to the fuel cladding tube performance under the reactivity introduction accident condition is determined.

2. The method according to claim 1, characterized in that The heating element of the simulated fuel rod is a high-temperature alloy thin-walled tube, the outer wall of the high-temperature alloy thin-walled tube is a spiral groove, and a solid ceramic corundum rod is installed inside the high-temperature alloy thin-walled tube, and the outer side of the ceramic corundum rod is a fuel cladding tube.

3. The method according to claim 1, characterized in that The construction of the simulated working condition when the simulated fuel rod is applied in the primary loop water environment of a pressurized water reactor includes: The primary water environment of the PWR is established through a high-temperature and high-pressure dynamic circulating water environment and a pressurized cooling water system; The chemical parameters and pressure of the loop water are controlled by the upward filling and downward discharge method, and the water quality of the loop water is controlled by the water chemical control loop, so as to establish a simulated working condition when simulating the fuel rods used in the primary loop water environment of a pressurized water reactor.

4. A fuel cladding performance test device under simulated reactivity introduction accident conditions, characterized in that: The device comprises: A construction module is used to construct a simulation condition when the fuel rod is used in the primary water environment of a pressurized water reactor; The measuring module is used to measure the temperature rise curves of multiple areas of the fuel cladding tube corresponding to the simulated fuel rods by heating the simulated fuel rods and increasing the temperature and pressure of the loop water of the primary loop water environment of the pressurized water reactor under the simulated working conditions, wherein a high-power power supply is used to perform a temperature rise test on the simulated combustion material rods, the heating adopts a low-voltage and high-current method, the fuel cladding tube and the internal heating element are synchronously powered on and heated, and four groups of thermocouples are used to measure the temperature of four different areas of the fuel cladding tube respectively to obtain the temperature rise curves of the four areas; A cooling module, used for cooling and reducing the pressure of the loop water to a preset temperature and pressure, taking out the simulated fuel rod, and cutting the simulated fuel rod axially into a preset number of small sections; An analysis module is used to perform chemical composition and microstructure analysis on each of the small sample sections to obtain surface chemical composition state change characteristics and surface profile structure data of the fuel cladding tubes in different temperature zones; A determination module, for constructing a fuel cladding tube performance test report based on the surface chemical composition state change characteristics and surface profile structure data in different temperature zones, and determining the fuel cladding tube performance under the reactivity introduction accident condition based on the fuel cladding tube performance test report; The determination module is specifically used for: Based on the surface chemical composition state change characteristics in different temperature zones, the surface chemical composition change curve is constructed; A fuel cladding tube performance test report is constructed based on the surface chemical composition change curve and the surface profile structure data, and a performance level corresponding to the fuel cladding tube performance under the reactivity introduction accident condition is determined based on the fuel cladding tube performance test report.

5. The device according to claim 4, characterized in that The heating element of the simulated fuel rod is a high-temperature alloy thin-walled tube, the outer wall of the high-temperature alloy thin-walled tube is a spiral groove, and a solid ceramic corundum rod is installed inside the high-temperature alloy thin-walled tube, and the outer side of the ceramic corundum rod is a fuel cladding tube.

6. The device according to claim 4, characterized in that The building blocks are specifically used for The primary water environment of the PWR is established through a high-temperature and high-pressure dynamic circulating water environment and a pressurized cooling water system; The chemical parameters and pressure of the loop water are controlled by the upward filling and downward discharge method, and the water quality of the loop water is controlled by the water chemical control loop, so as to establish a simulated working condition when simulating the fuel rods used in the primary loop water environment of a pressurized water reactor.

7. An electronic device, characterized in that: include: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 3.

8. A non-transitory computer-readable storage medium storing computer instructions, characterized in that: The computer instructions are used to cause the computer to execute the method according to any one of claims 1-3.

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