Numerical reactor, method for verifying reactor design by using numerical reactor, and method for predicting reactor operation

Abstract

Embodiments of the present application relate to the technical field of reactor numerical simulation, and in particular to a numerical reactor, a method for verifying a reactor design by using the numerical reactor, and a method for predicting reactor operation. The numerical reactor comprises: a physical-thermal structural module, configured to simulate a neutron field, a temperature field, and a stress field within a reactor core; a fuel-material module, configured to simulate a micro-structural change of a fuel during fission and a micro-structural change of a material of a reactor; and a coupling module, configured to couple a neutron field, a temperature field, and a stress field of the fuel-material module on the basis of a neutron field, a temperature field, and a stress field of the physical-thermal structural module, and to couple the neutron field, the temperature field, and the stress field of the physical-thermal structural module on the basis of the micro-structural changes of the material and the fuel of the fuel-material module. The numerical reactor of the embodiments of the present application is conducive to ensuring the accuracy and reliability of determined micro-structural changes of the fuel and the material, and the neutron field, the temperature field, and the stress field within the reactor core.

Description

Numerical reactors, methods for verifying reactor designs using numerical reactors, and methods for predicting reactor operation. Technical Field

[0001] The embodiments of this application relate to the field of reactor numerical simulation technology, specifically to a numerical reactor, a method for verifying reactor design using the same, and a method for predicting reactor operation. Background Technology

[0002] The statements herein are provided merely as background information in connection with this application and do not necessarily constitute prior art.

[0003] In the current field of nuclear energy utilization, nuclear reactor engineering, as a complex project involving multiple disciplines such as neutron physics, thermal fluid dynamics, systems analysis, mechanics, and radiation effects, typically requires the use of research tools for analysis. Among these tools, numerical reactors are an important one. Numerical reactors play a crucial role in gaining a deeper understanding of the physical characteristics of nuclear reactors, optimizing their design, and ensuring their safe operation.

[0004] However, current numerical reactor simulations face numerous challenges in practical applications. Due to the complexity and uncertainty of reactor systems, the established numerical reactor simulations often have low accuracy and cannot fully and accurately reflect the actual operation of the reactor. For example, in invention patent CN117454627A, a unified grid-based numerical reactor nuclear-thermal-material coupling simulation method is disclosed. This method integrates neutron physics, flow heat transfer, and material corrosion models to achieve unified solutions for the three physical processes under the same solver, enabling high-fidelity simulation of multiple physical processes in the nuclear reactor core. This method comprehensively considers the impact of cladding material oxidation and corrosion on reactor safety; however, it does not address the interaction between the changes in cladding material properties before and after irradiation and the changes in fuel performance before and after service, making it difficult to guarantee the accuracy of the determined cladding material corrosion. Summary of the Invention

[0005] A brief overview of this application is provided below to offer a basic understanding of certain aspects thereof. It should be understood that this overview is not an exhaustive summary of the application. It is not intended to identify key or essential parts of the application, nor is it intended to limit its scope. Its purpose is merely to present certain concepts in a simplified form as a prelude to the more detailed description that follows.

[0006] In a first aspect, embodiments of this application provide a numerical reactor, comprising: a physical-thermal-structure module configured to simulate the neutron field, temperature field, and stress field between reactor cores; a fuel material module configured to simulate the changes in the microstructure of the reactor fuel during fission, as well as the changes in the microstructure of the material; and a coupling module configured to couple the neutron field, temperature field, and stress field of the fuel material module to the neutron field, temperature field, and stress field based on the neutron field, temperature field, and stress field of the physical-thermal-structure module, and configured to couple the neutron field, temperature field, and stress field of the physical-thermal-structure module to the microstructure of the material and fuel in the fuel material module.

[0007] The embodiments of this application simulate the physical-thermal-structure module and the fuel material module on a multi-scale basis, and couple the simulation results through a coupling module. Based on the determined neutron field, temperature field, and stress field, the neutron field, temperature field, and stress field of the fuel material module can be determined. At the same time, based on the neutron field, temperature field, and stress field of the fuel material module, the neutron field, temperature field, and stress field of the physical-thermal-structure module can also be determined. This ensures the accuracy and reliability of the final determined changes in the microstructure of the fuel during fission, the changes in the microstructure of the materials, and the neutron field, temperature field, and stress field between reactor cores.

[0008] Secondly, embodiments of this application also provide a method for verifying reactor design, wherein the obtained reactor design parameters are input into the numerical reactor of the embodiments of this application; the numerical reactor operates according to the parameters and obtains the operating results; the operating results are compared with the expected results to determine whether the design parameters meet the expected design objectives.

[0009] Thirdly, embodiments of this application also provide a method for predicting reactor operation, which involves obtaining current actual operating data of the reactor; inputting the current actual operating data into the numerical reactor of this application embodiment; the numerical reactor operating according to the current actual operating data and obtaining operating results for a predetermined future time; and predicting the future operating status of the reactor based on the obtained operating results.

[0010] These and other advantages of this application will become more apparent from the following detailed description of preferred embodiments in conjunction with the accompanying drawings. Attached Figure Description

[0011] To further illustrate the above and other advantages and features of this application, the specific embodiments of this application will be described in more detail below with reference to the accompanying drawings. The drawings, together with the following detailed description, are included in and form a part of this specification. Elements having the same function and structure are indicated by the same reference numerals. It should be understood that these drawings only depict typical examples of this application and should not be considered as limiting the scope of this application.

[0012] Figure 1 is a schematic diagram of the structure of a numerical reactor according to an embodiment of this application;

[0013] Figure 2 is a schematic diagram of a specific structure of the numerical reactor shown in Figure 1;

[0014] Figure 3 is a schematic diagram of the structure of a numerical reactor according to another embodiment of this application;

[0015] Figure 4 is a schematic diagram of parameter correction for the material irradiation submodule and the fuel service performance submodule according to an embodiment of this application;

[0016] Figure 5 is a schematic diagram of the verification process of the verification module according to an embodiment of this application;

[0017] Figure 6 is a schematic diagram of multi-scale physical coupling according to an embodiment of this application;

[0018] Figure 7 is a schematic flowchart of a method for verifying reactor design according to an embodiment of this application;

[0019] Figure 8 is a schematic flowchart of a method for predicting reactor operation according to an embodiment of this application.

[0020] It should be noted that the accompanying drawings are not necessarily drawn to scale, but are shown only in a schematic manner without affecting the reader's understanding.

[0021] Explanation of reference numerals in the attached diagrams: 10. Physical-thermal-structure module; 20. Fuel material module; 21. Material irradiation sub-module; 211. Material neutron field; 212. Material stress field; 213. Material temperature field; 22. Fuel service performance sub-module; 30. Coupling module; 40. Neutron physics module; 50. Data-driven module; 51. Mapping relationship; 60. Verification module; 71. Measured data; 72. Prior physics knowledge. Detailed Implementation

[0022] Exemplary embodiments of this application will be described below with reference to the accompanying drawings. For clarity and brevity, not all features of actual implementations are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the development of any such actual embodiment to achieve the developer's specific goals, such as meeting constraints related to the system and business, and these constraints may vary depending on the implementation. Furthermore, it should be understood that while development work can be very complex and time-consuming, such development work is merely a routine task for those skilled in the art who benefit from the content of this application.

[0023] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the equipment structure and / or processing steps closely related to the solution according to this application are shown in the accompanying drawings, while other details that are not closely related to this application are omitted.

[0024] It should be noted that, unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning as understood by a person with ordinary skills in the field to which this application pertains.

[0025] In the description of the embodiments of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0026] An embodiment of this application provides a numerical reactor. FIG1 is a schematic diagram of the structure of a numerical reactor according to an embodiment of this application. As shown in FIG1, the numerical reactor may include at least a physical thermal structure module 10, a fuel material module 20, and a coupling module 30.

[0027] The physical thermal structure module 10 is configured to simulate the neutron field, temperature field, and stress field between reactor cores.

[0028] Fuel material module 20 is configured to simulate the changes in the microstructure of fuel and materials during the fission process in a reactor.

[0029] The coupling module 30 is configured to couple the neutron field, temperature field, and stress field of the fuel material module 20 to the neutron field, temperature field, and stress field of the physical thermal structure module 10, and is also configured to couple the neutron field, temperature field, and stress field of the physical thermal structure module 10 to the changes in the material and fuel microstructure of the fuel material module 20.

[0030] The embodiments of this application simulate the physical-thermal-structure module 10 and the fuel material module 20 on a multi-scale basis, and couple the simulation results through the coupling module 30. Based on the determined neutron field, temperature field and stress field, the neutron field, temperature field and stress field of the fuel material module 20 can be determined. At the same time, based on the neutron field, temperature field and stress field of the fuel material module 20, the neutron field, temperature field and stress field of the physical-thermal-structure module 10 can also be determined. This ensures the accuracy and reliability of the final determined changes in the microstructure of the fuel during the fission process, the changes in the microstructure of the materials, and the neutron field, temperature field and stress field between the reactor cores.

[0031] In some embodiments, the coupling of the neutron field, temperature field, and stress field of the physical thermal structure module 10 to the neutron field, temperature field, and stress field of the fuel material module 20 is performed in the following manner: Φ f(r,t+Δt)=f φ (T f (r,t),σ f (r,t),Φ c (r,t)); T f (r,t+Δt)=f T (T f (r,t),σ f (r,t),Φ f (r,t),T c (r,t)); σ f (r,t+Δt)=f σ (T f (r,t),σ f (r,t),Φ f (r,t),σ c (r,t)).

[0032] Where, Φ c (r,t) represents the neutron field between the cores of physical thermal structure module 10; T c (r,t) represents the temperature field between the cores of physical thermal structure module 10; σ c (r,t) represents the stress field between the cores of physical thermal structure module 10; Φ f (r,t) represents the neutron field of fuel material module 20; T f (r,t) represents the temperature field of fuel material module 20; σ f (r,t) represents the stress field of fuel material module 20; Φ f (r,t+Δt) represents the neutron field of the coupled fuel material module 20; T f (r,t+Δt) represents the temperature field of the coupled fuel material module 20; σ f (r,t+Δt) represents the stress field of the coupled fuel material module 20; r represents the spatial coordinates, where r≤r c r c The coordinates represent the outer boundary of the reactor cladding; t represents time; Δt represents the time increment in the iterative calculation; f φ This represents the function used to solve for the neutron field of fuel material module 20 using numerical methods; f T f represents the function used to solve the temperature field of fuel material module 20 using numerical methods; σ This represents a function that solves for the stress field of the fuel material module 20 using numerical methods.

[0033] The embodiments of this application utilize the neutron field, temperature field, and stress field of the physical thermal structure module 10 to couple the neutron field, temperature field, and stress field of the fuel material module 20 in the manner described above. The coupling effect is good, which helps to ensure the accuracy of the determined neutron field, temperature field, and stress field of the fuel material module 20.

[0034] In some embodiments, FIG2 is a specific structural schematic diagram of the numerical reactor shown in FIG1. ​​As shown in FIG1, the fuel material module 20 includes: a material irradiation submodule 21 and a fuel service performance submodule 22; the material irradiation submodule 21 is configured to simulate the changes in the properties of the material due to the changes in the microstructure of the reactor material after being irradiated; the fuel service performance submodule 22 is configured to simulate the changes in the microstructure of the fuel in the reactor during fission.

[0035] The embodiments of this application use a multi-scale simulation based on a material irradiation submodule 21 and a fuel service performance submodule 22, which can improve the accuracy and reliability of the final determined material performance variations and fuel service performance.

[0036] In some embodiments, the coupling module 30 is further configured to couple the service performance of the fuel based on changes in the microstructure of the material, and to couple the performance of the material based on changes in the microstructure of the fuel. This allows for the determination of the service performance of the fuel based on changes in the microstructure of the material, and the determination of the performance of the material based on changes in the microstructure of the fuel, thereby improving the accuracy and reliability of the ultimately determined service performance of the fuel and the performance of the material.

[0037] In some embodiments, the neutron field, temperature field, and stress field of the fuel material module 20 conform to the following expression regarding the microstructure of the fuel: G f (r,t+Δt)=f Gf (Φ f (r,t),T f (r,t),σ f (r,t),G f (r,t),G m (r,t)).

[0038] Among them, G f (r,t+Δt) represents the microstructure of the coupled fuel; f Gf Φ represents a function used to solve for the microstructure of fuel using numerical methods; f (r,t) represents the neutron field of fuel material module 20; T f (r,t) represents the temperature field of fuel material module 20; σ f (r,t) represents the stress field of fuel material module 20; G f(r,t) represents the fuel's microstructure at time t; G m (r,t) represents the material microstructure at time t; Δt represents the time increment in the iterative calculation.

[0039] In some embodiments, the neutron field, temperature field, stress field, and microstructure of the fuel material module 20 conform to the following expression: G m (r,t+Δt)=f Gm (Φ f (r,t),T f (r,t),σ f (r,t),G f (r,t),G m (r,t)).

[0040] Among them, G m (r,t+Δt) represents the microstructure of the coupled material; f Gm Φ represents a function used to solve for the microstructure of a material using numerical methods; f (r,t) represents the neutron field of fuel material module 20; T f (r,t) represents the temperature field of fuel material module 20; σ f (r,t) represents the stress field of fuel material module 20; G f (r,t) represents the fuel's microstructure at time t; G m (r,t) represents the material microstructure at time t; Δt represents the time increment in the iterative calculation.

[0041] In some embodiments, the changes in material properties include changes in the macroscopic mechanical properties or geometric integrity properties of the material; as shown in FIG2, the material irradiation submodule 21 is further configured to transmit the changes in the macroscopic mechanical properties or geometric integrity properties of the material determined by simulation to the fuel service performance submodule 22; the fuel service performance submodule 22 is further configured to correct the changes in fuel service performance based on the changes in the macroscopic mechanical properties or geometric integrity properties of the material.

[0042] The embodiments of this application utilize a material irradiation submodule 21 to determine changes in the macroscopic mechanical properties or geometric integrity properties of the material and transmit this information to a fuel service performance submodule 22. The fuel service performance submodule 22 then corrects for changes in the fuel service performance based on these changes, thereby accurately determining the fuel service performance during service.

[0043] In some embodiments, the material irradiation submodule 21 performs the function of transmitting the changes in the macroscopic mechanical properties or geometric integrity properties of the material determined by simulation to the fuel service performance submodule 22, and the fuel service performance submodule 22 performs the function of correcting the changes in the service performance of the fuel based on the changes in the macroscopic mechanical properties or geometric integrity properties of the material, which can be performed cyclically until a first predetermined duration is reached.

[0044] In some embodiments, the service performance of the fuel includes fission performance and fission product behavior. Fission performance includes temperature and stress distribution, and fission product behavior includes gaseous fission product behavior and solid fission product behavior. As shown in FIG2, the fuel service performance submodule 22 is further configured to: transmit the temperature and stress distribution of the fuel, gaseous fission products, and solid fission products determined by simulation to the material irradiation submodule 21. The material irradiation submodule 21 is configured to: determine the changes in the macroscopic mechanical properties or geometric integrity properties of the material based on the temperature and stress distribution of the fuel, gaseous fission products, and solid fission products.

[0045] The embodiments of this application utilize a fuel service performance submodule 22 to determine the temperature and stress distribution of the fuel, gaseous fission products, and solid fission products, and transfer them to a material irradiation submodule 21. The material irradiation submodule 21 then determines the changes in the macroscopic mechanical properties or geometric integrity properties of the material based on the temperature and stress distribution of the fuel, gaseous fission products, and solid fission products, thereby accurately determining the material's properties after irradiation.

[0046] In some embodiments, the fuel service performance submodule 22 performs the function of transferring the temperature and stress distribution of the fuel, gaseous fission products and solid fission products determined by simulation to the material irradiation submodule 21, and the material irradiation submodule 21 performs the function of determining the changes in the macroscopic mechanical properties or geometric integrity properties of the material based on the temperature and stress distribution of the fuel, gaseous fission products and solid fission products, which can be performed cyclically until a second predetermined duration is reached.

[0047] In such an embodiment, the first predetermined duration and the second predetermined duration can be the same.

[0048] In some embodiments, the coupling module 30 is specifically configured to couple the service performance of the fuel based on changes in the macroscopic mechanical properties or geometric integrity properties of the material, so as to ensure the reliability of the obtained service performance of the fuel.

[0049] In some embodiments, the coupling module 30 is specifically configured to couple the macroscopic mechanical properties or geometric integrity properties of the material based on the temperature and stress distribution of the fuel, gaseous fission products, and solid fission products, so as to ensure the reliability of the obtained macroscopic mechanical properties or geometric integrity properties of the material.

[0050] In some embodiments, as shown in FIG2, the material irradiation submodule 21 may include a material neutron field 211, a material stress field 212, and a material temperature field 213. The material neutron field 211 and the material temperature field 213 are configured to simulate the changes in the material under irradiation and temperature; the material stress field 212 and the material temperature field 213 are configured to simulate the changes in the material under stress and temperature; wherein, the coupling module 30 is configured to couple the material performance changes based on the simulation results of the material neutron field 211, the material stress field 212, and the material temperature field 213.

[0051] The embodiments of this application simulate the changes in the material under the material neutron field 211, the material stress field 212, and the material temperature field 213, and use the coupling module 30 to couple the simulation results, which helps to further improve the accuracy of determining the material changes.

[0052] In some embodiments, as shown in FIG2, the numerical reactor may further include a neutron physics module 40 for calculating the power density, nuclide distribution, etc. inside the fuel pellet.

[0053] In some embodiments, the input of the material neutron field 211 comes from the output of the neutron physics module 40.

[0054] In some embodiments, the input of the material stress field 212 is derived from the output of the fuel service performance submodule 22.

[0055] In some embodiments, the input of the material temperature field 213 is derived from the output of the fuel service performance submodule 22.

[0056] In some embodiments, the coupling module 30 couples the material neutron field 211, material stress field 212, and material temperature field 213 of the material irradiation submodule 21 by changing the generation, diffusion, and accumulation process of point defects in the material during service. Specifically, the coupling module 30 is used to: obtain a first concentration of point defects under the material temperature field 213; obtain a second concentration of point defects under the material neutron field 211 and the material temperature field 213; and obtain a third concentration of point defects under the material stress field 212 and the material temperature field 213.

[0057] The embodiments of this application couple the material neutron field 211, material stress field 212, and material temperature field 213 of the material irradiation submodule 21 by changing the generation, diffusion, and accumulation process of point defects in the material during service, and the coupling effect is relatively good.

[0058] In some embodiments, the total concentration of point defects under the coupling of the material subfield 211, the material stress field 212, and the material temperature field 213, together with the third concentration of point defects under the material stress field 212 and the material temperature field 213, the first concentration of point defects under the material temperature field 213, and the second concentration of point defects under the material subfield 211 and the material temperature field 213, satisfy the following expression: C = C1 + C2 - C0.

[0059] Wherein, C represents the total concentration of point defects under the coupling of the material subfield 211, the material stress field 212, and the material temperature field 213; C0 represents the first concentration of point defects under the material temperature field 213; C1 represents the second concentration of point defects under the material subfield 211 and the material temperature field 213; and C2 represents the third concentration of point defects under the material stress field 212 and the material temperature field 213.

[0060] In some embodiments, the coupling module 30 is further specifically used to: obtain a first diffusion coefficient of the point defect under the material temperature field 213; obtain a second diffusion coefficient of the point defect under the material neutron field 211 and the material temperature field 213; and obtain a third diffusion coefficient of the point defect under the material stress field 212 and the material temperature field 213.

[0061] In some embodiments, the second diffusion coefficient of the point defect under the material subfield 211 and the material temperature field 213, the first diffusion coefficient of the point defect under the material temperature field 213, the second concentration of the point defect under the material subfield 211 and the material temperature field 213, and the first concentration of the point defect under the material temperature field 213 satisfy the following expression:

[0062] Wherein, D1 represents the second diffusion coefficient of the point defect under the material neutron field 211 and the material temperature field 213; D0 represents the first diffusion coefficient of the point defect under the material temperature field 213; C1 represents the second concentration of the point defect under the material neutron field 211 and the material temperature field 213; and C0 represents the first concentration of the point defect under the material temperature field 213.

[0063] In some embodiments, the defect diffusion coefficient under the coupling of the material subfield 211, the material stress field 212, and the material temperature field 213 satisfies the following expression with respect to the third diffusion coefficient of point defects under the material stress field 212 and the material temperature field 213, the total concentration of point defects, and the third concentration of point defects under the material stress field 212 and the material temperature field 213:

[0064] Where D represents the defect diffusion coefficient under the coupling of the material neutron field 211, the material stress field 212, and the material temperature field 213; D2 represents the third diffusion coefficient of point defects under the material stress field 212 and the material temperature field 213; C represents the total concentration of point defects under the coupling of the material neutron field 211, the material stress field 212, and the material temperature field 213; and C2 represents the third concentration of point defects under the material stress field 212 and the material temperature field 213.

[0065] In some embodiments, the coupling module 30 is further specifically used to: control the evolution of defects using a governing equation for defect response under the conditions of a material neutron field 211, a material stress field 212, and a material temperature field 213. The governing equation is:

[0066] Where i, j, and k represent defects of different sizes; G i The term representing the generation of point defect i is input from the material neutron field 211; K and n represent the defect reaction rate constant and reaction radius; the second term on the right side of the governing equation represents the addition term from defect j to defect i, and the third term represents the decomposition, absorption, and disappearance term from defect i; C i C represents the concentration of defect i in the material; j C represents the concentration of defect j in the material; i-j C represents the concentration of defect ij in the material; k-i D represents the concentration of defects ki in the material; i D represents the diffusion coefficient of defect i in the material; j D represents the diffusion coefficient of defect j in the material; i-j D represents the diffusion coefficient of defect ij in the material; k-i The diffusion coefficient of defect ki in the material is represented by C; the concentration of defects C is represented by C. i C i-j C k-i and diffusion coefficient D i D i-j D k-i The defects are obtained by coupling the material under the material neutron field 211, the material stress field 212, and the material temperature field 213, respectively. The defect distribution function of the material under the coupling of the material neutron field 211, the material stress field 212, and the material temperature field 213 is determined based on the evolution of point defects. The changes in the macroscopic mechanical properties or geometric integrity properties of the material are determined based on the defect distribution function.

[0067] In some embodiments, the fuel service performance submodule 22 includes: a temperature distribution unit, a stress distribution unit, a microstructure evolution unit, a fission gas behavior unit, and a solid fission product behavior unit; wherein, the temperature distribution unit is configured to simulate the change in fuel temperature distribution during the fission reaction; the stress distribution unit is configured to simulate the change in fuel stress distribution during the fission reaction; the microstructure evolution unit is configured to simulate the change in the microstructure of the fuel during the fission reaction; the fission gas behavior unit is configured to simulate the change in fuel swelling and the amount of gas released into the gas cavity caused by the fission gas generated during the fission reaction; and the solid fission product behavior unit is configured to simulate the distribution change of solid fission products generated during the fission reaction in the fuel.

[0068] The embodiments of this application configure the fuel service performance submodule 22 to include a temperature distribution unit, a stress distribution unit, a microstructure evolution unit, a fission gas behavior unit, and a solid fission product behavior unit. Different units can be used to simulate and obtain the changes in the fuel temperature field, the changes in the fuel stress field, the microstructure evolution, the fission gas behavior, and the solid fission product behavior of the fuel, which has high reliability.

[0069] In some embodiments, the numerical reactor may further include a thermal-hydraulic module for simulating the thermal-hydraulic properties of the reactor to determine the coolant pressure and the temperature distribution on the outer surface of the fuel rod cladding.

[0070] In some embodiments, the input to the temperature distribution unit comes from the outputs of the neutron physics module and the thermal-hydraulic module.

[0071] In some embodiments, the input to the stress distribution unit comes from the outputs of the neutron physics module and the thermal-hydraulic module.

[0072] In some embodiments, the input to the microstructure evolution unit comes from the output of the neutron physics module.

[0073] In some embodiments, the input to the fission gas behavior unit is derived from the output of the neutron physics module.

[0074] In some embodiments, the input to the solid-state fission product unit is derived from the output of the neutron physics module.

[0075] In some embodiments, the coupling module 30 is further configured to couple the behavior of fission gas, the behavior of solid fission products, the evolution of microstructure, the changes in fuel stress field and fuel temperature field to obtain changes in the internal composition, structure, thermal conductivity and geometric integrity of the fuel.

[0076] In some embodiments, the fission gas behavior, solid fission products, microstructure evolution, fuel stress field, and fuel temperature field in the fuel service performance submodule 22 are determined by coupling the temperature distribution unit, stress distribution unit, microstructure evolution unit, fission gas behavior unit, and solid fission product behavior unit.

[0077] In some embodiments, the coupling module 30 is specifically configured to: during the coupling process, update the temperature and stress distribution of the fuel during service, as well as the changes in microstructure, fission gas and solid fission product behavior, in the order of simulation of temperature distribution unit, stress distribution unit, microstructure evolution unit, fission gas behavior unit and solid fission product behavior unit at predetermined time intervals.

[0078] In some embodiments, the temperature distribution unit is specifically configured to: describe the temperature distribution of the fuel within a predetermined space using a three-dimensional heat conduction equation, wherein the three-dimensional heat conduction equation is:

[0079] Where T represents the temperature of the fuel; t represents time; c represents the coordinates of a point on the fuel rod within a predetermined space. v q represents the heat capacity per unit volume; q represents the volumetric heat release rate. It represents the thermal conductivity of fuel, which is related to the internal chemical composition and microstructure of the fuel.

[0080] In some embodiments, the microstructure evolution unit is specifically configured to: describe the changes in the microstructure of fuel during fission reactions to obtain structural information about the microstructure, wherein the changes in microstructure include chemical composition, phase structure, grain size and morphology, and porosity; wherein the evolution of non-conserved order parameters and conserved order parameters of phase structure, grain size, morphology, and porosity is controlled by a predetermined evolution equation, which is:

[0081] in, L represents non-conserved order parameters for phase structure, grain size, morphology, and porosity; i (g,T,σ) represents the diffusion mobility of the fuel's non-conservative order parameters; F represents the fuel's free energy equation; c i The conserved order parameters representing phase structure, grain size, morphology, and porosity; J T J represents temperature-driven diffusion flux. c M represents the diffusion flux driven by free energy; i (g,T,σ) represents the free energy-driven chemical mobility; M T(g,T,σ) represents the temperature-driven thermodynamic mobility; t represents the service time of the fuel; and T represents the service temperature of the fuel.

[0082] In some embodiments, the predetermined evolution equation can be the reaction-diffusion (Allen-Cahn) and Cahn-Hilliard equations.

[0083] In some embodiments, fuel microstructure information, denoted as g, can be obtained through the calculation of microstructure evolution units. This information includes the fuel phase structure str, the elemental composition c of the fuel, and the fuel grain size r. g fuel grain boundary morphology g And information about porosity p. The fuel microstructure information g satisfies the following expression: g = f g (str,c,r g geo g ,p)+g fis .

[0084] Among them, g fis It represents the microstructure changes caused by solid fission products, and can be used as an input parameter for the behavior of gaseous and solid fission products in fission reactions.

[0085] In some embodiments, the fission gas behavior unit is specifically configured to: describe the transport, induced swelling, and release of fission gas in the fuel to obtain the distribution of fission gas within the grain, at grain boundaries, and on grain edges, the release amount of fission gas, the induced swelling, and the porosity distribution, wherein the fission gas includes xenon and krypton.

[0086] In some embodiments, the distribution of fission gas within the grains, at grain boundaries, and on grain edges, and the amount of fission gas released satisfy the following expression:

[0087] Among them, w rea The amount of fission gas released is represented by t; the service life of the fuel is represented by t; q(g,T,σ) represents the migration coefficient of bubbles from the crystal face to the crystal edge; C f P represents the bubble concentration at the grain boundary; C represents the bubble release coefficient at the grain edge. e The concentration of bubbles on the crystal edge is represented by n(g,T,σ); n(g,T,σ) represents the direct release coefficient of bubbles on the crystal face.

[0088] In some embodiments, the distribution of fission gas within the grain, at grain boundaries, and on grain edges, and the swelling caused by the fission gas, satisfy the following expression:

[0089] Where, ΔV α Indicates swelling caused by fission gas; r i This represents the radius of the bubble of size i.

[0090] In some embodiments, based on the distribution of fission gas within the grains, at grain boundaries, and on grain edges, the porosity distribution of the fuel satisfies the following expression:

[0091] in, This indicates the porosity distribution of the fuel; This represents the distribution of the initial fuel void fraction; P′(r i ) represents the porosity distribution caused by fission gas.

[0092] In some embodiments, the fission gas may be xenon (Xe) and krypton (Kr), etc.

[0093] In some embodiments, the fission gas behavior unit primarily considers the generation of fission gas during the fission process. The gas diffuses through fuel grains, forming and coalescing into bubbles, which then grow and diffuse to the grain boundaries. Retention within the fuel causes fuel swelling. As burnup increases, the bubbles at the grain boundaries connect, forming fission gas release channels, which release the fission gas into the gap between the fuel and the cladding. The fission gas atomic concentration C in the fuel... g C b Bubble concentration C at grain boundaries f And the bubble concentration C on the crystal edge e Primarily dominated by the bubble evolution governing equations:

[0094] Where a(g,T,σ) represents the bubble nucleation coefficient; b(g,T,σ) represents the bubble absorption coefficient; D g d represents the gas diffusion coefficient; g σ represents the grain diameter; s represents the gas generation rate; e(g,T,σ) represents the intracrystalline bubble resolution coefficient; h(g,T,σ) represents the crystal face (or crystal edge) bubble resolution coefficient; l(g,T,σ) represents the grain boundary bubble absorption coefficient; m(g,T,σ) represents the crystal face (or crystal edge) bubble detachment coefficient; n(g,T,σ) represents the crystal face bubble direct release coefficient; q(g,T,σ) represents the crystal face bubble migration to crystal edge coefficient; P represents the crystal edge bubble release coefficient; N b N represents the average number of bubbles per grain; f N represents the average number of bubbles per crystal plane; e The number of bubbles in the grain is represented by r; the distance from the grain center to the grain center is represented by r in a spherical coordinate system; and the evolution time is represented by t.

[0095] In some embodiments, the distribution of fission gas within the grains, at grain boundaries, and on grain edges, and the amount of fission gas released, w, can be obtained by solving the above-mentioned bubble evolution governing equations. reaThe resulting swelling ΔV α and porosity distribution

[0096] In some embodiments, the solid fission product behavior unit is specifically configured to: describe the behavior of solid fission products generated during the fission process, in order to determine the precipitate phase, migration behavior, and spatial distribution of fuel solid fission products, wherein the behavior of solid fission products includes the behavior of strontium, cesium, iodine, and lanthanum / actinide fission products, and the behavior of solid fission products can be controlled by a predetermined evolution equation in the embodiments of this application.

[0097] In some embodiments, the precipitate phase, migration behavior, and spatial distribution of fuel solid fission products can be obtained through the calculation of solid fission product behavior units, denoted as g. fis This includes information about the structure of the fuel precipitate phase. fis-pre Concentration distribution C fis And the diffusion of solid fission products in fuel D fis Among them, migration behavior and spatial distribution g fis Satisfying the following expression: g fis =f g-fis (str fis-pre C fis D fis ).

[0098] Among them, f g-fis This represents a function used to solve for the behavior of fuel solid-state fission products using numerical methods.

[0099] In some embodiments, the coupling module 30 is further configured to: simulate the temperature distribution of the fuel determined by the fuel service performance submodule 22. Stress distribution Release amount of fission gas w rea and the distribution of solid-state fission products g fis The data is passed to the material irradiation submodule 21 to perform multi-scale simulations based on the material and update the irradiation damage behavior of the material under new temperature, stress, and fission gas and solid-state fission conditions, thereby improving the accuracy of the changes in the macroscopic mechanical properties or geometric integrity properties of the material obtained from the simulation.

[0100] In some embodiments, the coupling module 30 is further configured to: change the mechanical properties of the material g fis Geometric integrity parameter Δε c and the distribution of microstructural defects N i =f(d iThe temperature distribution unit, stress distribution unit, and microstructure evolution unit in the fuel service performance submodule 22 are passed to update the fuel service performance, thereby improving the accuracy of the simulated changes in fuel service performance.

[0101] In some embodiments, FIG3 is a schematic diagram of the structure of a numerical reactor according to another embodiment of the present application. As shown in FIG3, the numerical reactor further includes a data-driven module, which is configured to determine the mapping relationship between the actual irradiation results of the reactor and the simulation results of the material irradiation submodule 21 and the simulation results of the fuel service performance submodule 22.

[0102] In some embodiments, as shown in FIG3, the numerical reactor further includes a verification module 60, which is configured to determine the accuracy of the simulation results of the material irradiation submodule 21 and the fuel service performance submodule 22 based on the actual irradiation results of the reactor and the mapping relationship between the actual irradiation results of the reactor and the simulation results of the material irradiation submodule 21 and the fuel service performance submodule 22.

[0103] The numerical reactor provided in the embodiments of this application verifies the accuracy of the service performance of fuel and materials by using the verification module 60 to verify the mapping relationship between the actual irradiation results of the reactor and the simulation results of the material irradiation submodule 21 and the fuel service performance submodule 22. This facilitates the correction of the parameters of the numerical reactor, making the calculation results of the numerical reactor more accurate and reliable, and also avoids the situation where the actual irradiation results of the reactor are insufficient.

[0104] In some embodiments, the actual irradiation results of the reactor may include measured data of the reactor and prior physics knowledge.

[0105] In some embodiments, the data-driven module 50 obtains data by: acquiring measured data and prior physics knowledge of the reactor, wherein the measured data includes the reactor's temperature, pressure, flow rate, neutron flux, and power distribution; determining the data-driven module 50 for cross-scale multi-physical feature fusion based on the measured data and prior physics knowledge; and correcting the parameters of the data-driven module 50 according to the output of the data-driven module 50, the measured data, and the prior physics knowledge.

[0106] The data-driven module 50 obtained by the method provided in the embodiments of this application is advantageous in ensuring that the data-driven module 50 follows physical laws when fusing features at different scales, and has high reliability.

[0107] Figure 4 is a schematic diagram of the correction of parameters of material irradiation submodule 21 and fuel service performance submodule 22 according to an embodiment of this application. As shown in Figure 4, on the one hand, the parameters of material irradiation submodule 21 and fuel service performance submodule 22 can be directly corrected using measured data 71 and prior physical knowledge 72; on the other hand, the parameters of material irradiation submodule 21 and fuel service performance submodule 22 can be indirectly corrected according to the mapping relationship 51 determined by the data-driven module.

[0108] In some embodiments, the measured data 71 may include experimental data, actual reactor operation data, and other data. When collecting the measured data 71, attention is paid not only to the macroscopic operating parameters of the reactor, but also to the collection of interrelated data at different scales through multi-scale experimental equipment and measurement methods.

[0109] In some embodiments, the measured data 71 of the reactor may include, but is not limited to, key parameters such as temperature, pressure, flow rate, neutron flux, and power distribution. To ensure the diversity and representativeness of the data, the measured data 71 may correspond to the reactor state under different operating conditions and working conditions.

[0110] In some embodiments, the collected measured data 71 can be cleaned to remove outliers and erroneous data. For example, the collected measured data 71 can be denoised using methods such as filtering to reduce the impact of measurement noise on the data, thereby improving data quality. Alternatively, the collected measured data 71 can be normalized to bring the data of different parameters to the same order of magnitude, facilitating subsequent analysis and processing.

[0111] Figure 5 is a schematic diagram of the verification process of the verification module 60 according to an embodiment of the present application. As shown in Figure 5, the verification module 60 is used to perform the following steps S1 to S5.

[0112] S1. Constructing a calculation example, which includes: directly constructing a calculation example based on measured data 71 and prior physical knowledge 72; and indirectly constructing a calculation example based on the mapping relationship 51 between the actual irradiation results of the reactor determined by the data-driven module 50 and the simulation results of the material irradiation submodule 21 and the fuel service performance submodule 22.

[0113] S2, Module Operation, which includes: running the material irradiation submodule 21 and the fuel service performance submodule 22 based on directly constructed and indirectly constructed examples to obtain the simulation results of the material irradiation submodule 21 and the fuel service performance submodule 22.

[0114] S3. Module analysis, which includes: comparative analysis to identify the differences and deficiencies between the material irradiation submodule 21 and the fuel service performance submodule 22. For example, the material irradiation submodule 21 or the fuel service performance submodule 22 may have inaccurate calculations for certain specific types, or the module parameters may need further optimization. By identifying the differences and deficiencies, the aspects that need to be corrected can be determined.

[0115] S4. Module parameter optimization, which includes: optimizing the parameters of the material irradiation submodule 21 and the fuel service performance submodule 22 based on comparative analysis and the reasons for the differences. This can be achieved by adjusting the parameter value range, adding other key parameters, or considering nonlinear relationships to enhance the module's adaptability and predictive ability. In the optimization process, a trial-and-error method can be used to find a better parameter combination through multiple parameter adjustments and runs. Alternatively, a genetic algorithm can be applied to optimize the module parameters by simulating the biological evolution process to find the optimal module parameter combination to minimize the error between the module's predicted value and the measured data 71.

[0116] S5. Module verification and evaluation, which includes: after the module parameters are optimized, verifying and evaluating the optimized material irradiation submodule 21 and fuel service performance submodule 22 to ensure that the simulation results obtained based on the modified material irradiation submodule 21 and fuel service performance submodule 22 are closer to the measured data 71.

[0117] In some embodiments, FIG6 is a schematic diagram of multi-scale physical coupling according to an embodiment of the present application. As shown in FIG6, a multi-scale physical coupling module can be constructed based on a master-slave architecture using a neutron transport program, fuel consumption program, thermal fluid calculation program, structural mechanics calculation program, fuel performance analysis program, and material performance analysis program of a single physical process. The multi-scale physical coupling module can be divided into a control layer, a driving layer, a data layer, and an execution layer according to functional requirements.

[0118] Based on grid type and simulation parameters, establishing a representation standard and unified interface for grid data and parameters is beneficial for saving storage resources and improving access efficiency; based on efficient positioning data indexing and interpolation algorithms for different spatial discretization forms, efficient parameter conversion and transfer are achieved, which is beneficial for improving coupling efficiency; based on specific coupled calculation models, establishing a mapping relationship for coupled parameter transfer functions is beneficial for improving the accuracy of coupled parameter transfer; based on single-level and multi-level time step control methods, it is beneficial for balancing simulation accuracy and computation time.

[0119] The embodiments of this application also provide a method for verifying a reactor design. FIG7 is a schematic flowchart of the method for verifying a reactor design according to an embodiment of this application. As shown in FIG7, it includes the following steps S10 to S30.

[0120] S10. Input the obtained reactor design parameters into the numerical reactor of this application embodiment.

[0121] S20, the numerical reactor operates according to the parameters and obtains the operating results.

[0122] S30. Compare the running results with the expected results to determine whether the design parameters meet the expected design goals.

[0123] The method provided in the embodiments of this application verifies the designed reactor by inputting the obtained reactor design parameters into the numerical reactor provided in the embodiments of this application. This verifies whether the reactor design values ​​meet the requirements and corrects the design values ​​based on the operation of the numerical reactor. Furthermore, the above-mentioned numerical reactor is also applicable to verifying the materials of the reactor internals, and further guiding the research and development of internal materials based on the verification results.

[0124] The embodiments of this application also provide a method for predicting reactor operation. FIG8 is a schematic flowchart of the method for predicting reactor operation according to the embodiments of this application. As shown in FIG8, it includes the following steps S40 to S70.

[0125] S40. Obtain the current actual operating data of the reactor.

[0126] S50. Input the current actual operating data into the numerical reactor of this application embodiment.

[0127] S60, the numerical reactor operates according to the current actual operating data and obtains the operating results at a predetermined time in the future.

[0128] S70. Based on the obtained operating results, predict the future operating status of the reactor.

[0129] The method provided in the embodiments of this application can utilize data from currently operating reactors, input this data into the numerical reactor provided in the embodiments of this application, and operate the numerical reactor based on this data. Therefore, future reactor data can be obtained, i.e., the future operating conditions of the actual reactor can be predicted. Based on the predictions, the possible future service conditions of the reactor can be determined, and safety measures can be taken in advance for special circumstances, thereby improving the reliability of reactor operation.

[0130] It is understood that there is no specific execution order between steps S30 and S40 in the embodiments of this application.

[0131] Regarding the embodiments of this application, it should also be noted that, without conflict, the embodiments of this application and the features in the embodiments can be combined with each other to obtain new embodiments.

[0132] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. The scope of protection of this application shall be determined by the scope of the claims.

Claims

1. A numerical reactor, characterized in that, It includes: The physical thermal structure module is configured to simulate the neutron field, temperature field, and stress field between reactor cores. The fuel material module is configured to simulate the changes in the microstructure of the fuel in the reactor during the fission process, as well as the changes in the microstructure of the materials. The coupling module is configured to couple the neutron field, temperature field, and stress field of the fuel material module to the neutron field, temperature field, and stress field of the physical thermal structure module, and is configured to couple the neutron field, temperature field, and stress field of the physical thermal structure module to the changes in the material and fuel microstructure of the fuel material module.

2. The numerical reactor according to claim 1, characterized in that, The coupling of the neutron field, temperature field, and stress field of the physical thermal structure module to the neutron field, temperature field, and stress field of the fuel material module is carried out in the following manner: Φ f (r,t+Δt)=f φ (T f (r,t),σ f (r,t),Φ c (r,t)); T f (r,t+Δt)=f T (T f (r,t),σ f (r,t),Φ f (r,t),T c (r,t)); σ f (r,t+Δt)=f σ (T f (r,t),σ f (r,t),Φ f (r,t),σ c (r,t)); Where, Φ c (r,t) represents the neutron field between the cores of the physical thermal structure module; T c (r,t) represents the temperature field between the cores of the physical thermal structure module; σ c (r,t) represents the stress field between the cores of the physical thermal structure module; Φ f (r,t) represents the neutron field of the fuel material module; T f (r,t) represents the temperature field of the fuel material module; σ f (r,t) represents the stress field of the fuel material module; Φ f (r,t+Δt) represents the neutron field of the coupled fuel material module; T f (r,t+Δt) represents the temperature field of the coupled fuel material module; σ f (r,t+Δt) represents the stress field of the coupled fuel material module; r represents the spatial coordinates, where r≤r c r c The coordinates of the outer boundary of the reactor cladding are represented by: t represents time; Δt represents the time increment in the iterative calculation; f φ f represents a function used to solve for the neutron field of the fuel material module using numerical methods; T f represents a function that solves for the temperature field of the fuel material module using numerical methods; σ This represents a function that solves for the stress field of the fuel material module using numerical methods.

3. The numerical reactor according to claim 1, characterized in that, The fuel materials module includes: a materials irradiation submodule and a fuel service performance submodule; The material irradiation submodule is configured to simulate the changes in material properties caused by changes in the microstructure of the reactor material after irradiation. The fuel service performance submodule is configured to simulate the changes in the microstructure of fuel in the reactor during fission.

4. The numerical reactor according to claim 3, characterized in that, The coupling module is further configured to couple the service performance of the fuel based on changes in the microstructure of the material, and to couple the performance of the material based on changes in the microstructure of the fuel.

5. The numerical reactor according to claim 3, characterized in that, The neutron field, temperature field, and stress field of the fuel material module, along with the microstructure of the fuel, conform to the following expressions: G f (r,t+Δt)=f Gf (Φ f (r,t),T f (r,t),σ f (r,t),G f (r,t),G m (r,t)); The neutron field, temperature field, stress field, and microstructure of the fuel material module conform to the following expressions: G m (r,t+Δt)=f Gm (Φ f (r,t),T f (r,t),σ f (r,t),G f (r,t),G m (r,t)); Among them, G f (r,t+Δt) represents the microstructure of the coupled fuel; G m (r,t+Δt) represents the microstructure of the coupled material; Φ f (r,t) represents the neutron field of the fuel material module; T f (r,t) represents the temperature field of the fuel material module; σ f (r,t) represents the stress field of the fuel material module; G f (r,t) represents the microstructure of the fuel at time t; G m (r,t) represents the microstructure of the material at time t; Δt represents the time increment in the iterative calculation; f Gf f represents a function that solves for the microstructure of the fuel using numerical methods; Gm This represents a function that solves for the microstructure of the material using numerical methods.

6. The numerical reactor according to claim 3, characterized in that, The changes in the material's properties include: changes in the material's macroscopic mechanical properties or geometric integrity properties; The material irradiation submodule is further configured to transmit the changes in the macroscopic mechanical properties or geometric integrity properties of the material determined by simulation to the fuel service performance submodule; The fuel service performance submodule is further configured to: correct changes in the service performance of the fuel based on changes in the macroscopic mechanical properties or geometric integrity properties of the material.

7. The numerical reactor according to claim 6, characterized in that, The service performance of the fuel includes its fission properties and the behavior of its fission products. The fission properties include temperature and stress distribution, and the fission product behavior includes gaseous fission product behavior and solid fission product behavior. The fuel service performance submodule is further configured to transmit the temperature and stress distribution of the fuel, gaseous fission products and solid fission products determined by simulation to the material irradiation submodule. The material irradiation submodule is configured to determine the changes in the macroscopic mechanical properties or geometric integrity properties of the material based on the temperature and stress distribution of the fuel, gaseous fission products, and solid fission products.

8. The numerical reactor according to claim 7, characterized in that, The coupling module is specifically configured as follows: The service performance of the fuel is coupled based on the changes in the macroscopic mechanical properties or geometric integrity properties of the material.

9. The numerical reactor according to claim 7, characterized in that, The coupling module is specifically configured as follows: The macroscopic mechanical properties or geometric integrity properties of the material are coupled based on the temperature and stress distribution of the fuel, gaseous fission products, and solid fission products.

10. The numerical reactor according to claim 6, characterized in that, The material irradiation submodule includes a material neutron field, a material stress field, and a material temperature field. The nucleus field and temperature field of the material are configured to simulate the changes that occur in the material under irradiation and temperature. The material stress field and the material temperature field are configured to simulate the changes that occur in the material under stress and temperature. The coupling module is configured to couple the performance changes of the material based on the simulation results of the material's neutron field, stress field, and temperature field.

11. The numerical reactor according to claim 10, characterized in that, The coupling module achieves the coupling of the material neutron field, material stress field, and material temperature field of the material irradiation submodule by changing the generation, diffusion, and accumulation process of point defects in the material during service. Specifically, the coupling module is used for: Under the material temperature field, the first concentration of the point defects is obtained; Under the conditions of the nucleus field and the temperature field of the material, a second concentration is obtained to generate the point defects; Under the material stress field and the material temperature field, a third concentration is obtained to generate the point defects.

12. The numerical reactor according to claim 11, characterized in that, The total concentration of point defects under the coupling of the material's neutron field, stress field, and temperature field, along with the third concentration of point defects under the material's stress field and temperature field, the first concentration of point defects under the material's temperature field, and the second concentration of point defects under the material's neutron field and temperature field, satisfy the following expression: C = C1 + C2 - C0; Wherein, C represents the total concentration of the point defect under the coupling of the material's neutron field, stress field, and temperature field; C0 represents the first concentration of the point defect under the material's temperature field; C1 represents the second concentration of the point defect under the material's neutron field and temperature field; and C2 represents the third concentration of the point defect under the material's stress field and temperature field.

13. The numerical reactor according to claim 12, characterized in that, The coupling module is also specifically used for: Under the temperature field of the material, the first diffusion coefficient of the point defect is obtained; Under the conditions of the neutron field and the temperature field of the material, the second diffusion coefficient of the point defect is obtained; The third diffusion coefficient of the point defect is obtained under the stress field and temperature field of the material.

14. The numerical reactor according to claim 13, characterized in that, The second diffusion coefficient of the point defect under the numeric field and the temperature field of the material, together with the first diffusion coefficient of the point defect under the temperature field of the material, the second concentration of the point defect under the numeric field and the temperature field of the material, and the first concentration of the point defect under the temperature field of the material, satisfy the following expression: Wherein, D1 represents the second diffusion coefficient of the point defect under the nucleus field and the temperature field of the material; D0 represents the first diffusion coefficient of the point defect under the temperature field of the material; C1 represents the second concentration of the point defect under the nucleus field and the temperature field of the material; and C0 represents the first concentration of the point defect under the temperature field of the material.

15. The numerical reactor according to claim 14, characterized in that, The defect diffusion coefficient under the coupling of the material's subfield, stress field, and temperature field, along with the third diffusion coefficient of the point defect under the material's stress and temperature fields, the total concentration of the point defect, and the third concentration of the point defect under the material's stress and temperature fields, satisfy the following expression: Wherein, D represents the defect diffusion coefficient under the coupling of the material's neutron field, stress field, and temperature field; D2 represents the third diffusion coefficient of the point defect under the material's stress field and temperature field; C represents the total concentration of the point defect under the coupling of the material's neutron field, stress field, and temperature field; and C2 represents the third concentration of the point defect under the material's stress field and temperature field.

16. The numerical reactor according to claim 15, characterized in that, The coupling module is also specifically used for: Under the conditions of the material's neutron field, stress field, and temperature field, the evolution of defects is controlled by a governing equation for the defect response. This governing equation is: Where i, j, and k represent defects of different sizes; G i The term representing the generation of point defect i is input from the subfield of the material; K and n represent the defect reaction rate constant and reaction radius; the second term on the right side of the governing equation represents the addition term from defect j to defect i, and the third term represents the decomposition, absorption, and disappearance term from defect i; C i C represents the concentration of defect i in the material; j C represents the concentration of defect j in the material; i-j C represents the concentration of defect ij in the material; k-i D represents the concentration of defects ki in the material; i D represents the diffusion coefficient of defect i in the material; j D represents the diffusion coefficient of defect j in the material; i-j D represents the diffusion coefficient of defect ij in the material; k-i The diffusion coefficient of defect ki in the material is represented by C; the concentration of the defect is represented by C. i C i-j C k-i and diffusion coefficient D i D i-j D k-i It is obtained by coupling the material's neutron field, stress field, and temperature field, respectively. The defect distribution function of the material under the coupling of the material's neutron field, stress field, and temperature field is determined based on the evolution of the point defects; the changes in the material's macroscopic mechanical properties or geometric integrity properties are determined based on the defect distribution function.

17. The numerical reactor according to claim 7, characterized in that, The fuel service performance submodule includes: a temperature distribution unit, a stress distribution unit, a microstructure evolution unit, a fission gas behavior unit, and a solid fission product behavior unit; wherein... The temperature distribution unit is configured to simulate the changes in fuel temperature distribution during the fission reaction. The stress distribution unit is configured to simulate the change in fuel stress distribution during the fission reaction. The microstructure evolution unit is configured to simulate the changes in the microstructure of the fuel during the fission reaction; The fission gas behavior unit is configured to simulate the changes in fuel swelling and the amount of gas released into the gas chamber caused by the fission gas produced by the fuel in the fission reaction. The solid fission product behavior unit is configured to simulate the distribution changes of solid fission products generated by the fuel in the fission reaction within the fuel.

18. The numerical reactor according to claim 17, characterized in that, The coupling module is further configured as follows: The behavior of the fission gas, the behavior of the solid fission products, the evolution of the microstructure, the changes in the fuel stress field and the fuel temperature field are coupled to obtain the changes in the internal composition, structure, thermal conductivity and geometric integrity of the fuel.

19. The numerical reactor according to claim 18, characterized in that, By coupling the temperature distribution unit, the stress distribution unit, the microstructure evolution unit, the fission gas behavior unit, and the solid fission product behavior unit, the fission gas behavior, solid fission products, microstructure evolution, fuel stress field, and fuel temperature field in the fuel service performance submodule are determined.

20. The numerical reactor according to claim 19, characterized in that, The coupling module is specifically configured as follows: During the coupling process, the temperature and stress distribution, as well as the changes in microstructure, fission gas and solid fission product behavior of the fuel during service, are updated at predetermined time intervals in the order of simulation of the temperature distribution unit, the stress distribution unit, the microstructure evolution unit, the fission gas behavior unit, and the solid fission product behavior unit.

21. The numerical reactor according to claim 20, characterized in that, The fission gas behavior unit is specifically configured to: describe the transport, swelling and release of fission gas in fuel, so as to obtain the distribution of fission gas in the grain, grain boundary and grain edge, the release amount of fission gas, the swelling caused and the porosity distribution. The fission gases include xenon and krypton.

22. The numerical reactor according to claim 21, characterized in that, The distribution of the fission gas within the grains, at grain boundaries, and on grain edges, and the release amount of the fission gas satisfy the following expression: Among them, w rea The amount of fission gas released is represented by t; the service time of the fuel is represented by t; q(g,T,σ) represents the migration coefficient of bubbles from the crystal face to the crystal edge; C f P represents the bubble concentration at the grain boundary; C represents the bubble release coefficient at the grain edge. e The concentration of bubbles on the crystal edge is represented by n(g,T,σ); n(g,T,σ) represents the direct release coefficient of bubbles on the crystal face.

23. The numerical reactor according to claim 22, characterized in that, The distribution of the fission gas within the grains, at grain boundaries, and on grain edges, and the porosity distribution of the fuel satisfy the following expression: in, This indicates the porosity distribution of the fuel; This represents the distribution of the initial fuel void fraction; P'(r i ) represents the porosity distribution caused by fission gas.

24. The numerical reactor according to claim 23, characterized in that, The solid-state fission product behavior unit is specifically configured as follows: Describe the behavior of solid fission products generated during the fission process to determine the solid fission product precipitate phase, migration behavior, and spatial distribution of the fuel. The behavior of the solid-state fission products includes the behavior of strontium, cesium, iodine, and lanthanum / actinide fission products, and the behavior of the solid-state fission products is controlled by a predetermined evolution equation.

25. The numerical reactor according to claim 20, characterized in that, The coupling module is further configured to transmit the temperature distribution, stress distribution, fission gas release, and solid fission product distribution of the fuel, as determined by the fuel service performance submodule, to the material irradiation submodule, so as to perform multi-scale simulation based on the material and update the irradiation damage behavior of the material under new temperature, stress, fission gas, and solid fission conditions.

26. The numerical reactor according to claim 20, characterized in that, The coupling module is further configured to transmit the changes in the mechanical properties, geometric integrity parameters, and microstructure defect distribution of the material to the temperature distribution unit, the stress distribution unit, and the microstructure evolution unit in the fuel service performance submodule, so as to update the service performance of the fuel.

27. The numerical reactor according to any one of claims 3-26, characterized in that, It also includes a data-driven module. The data-driven module is configured to determine the mapping relationship between the actual irradiation results of the reactor and the simulation results of the material irradiation submodule and the simulation results of the fuel service performance submodule.

28. The numerical reactor according to claim 27, characterized in that, The data-driven module obtains the data in the following way: Acquire measured data and prior physics knowledge of the reactor, including the reactor's temperature, pressure, flow rate, neutron flux, and power distribution; Based on the measured data and the prior physical knowledge, a data-driven module for cross-scale multi-physical feature fusion is determined. Based on the output of the data-driven module, the measured data, and the prior physical knowledge, the parameters of the data-driven module are corrected.

29. The numerical reactor according to claim 28, characterized in that, It also includes a verification module. The verification module is configured to: determine the accuracy of the simulation results of the material irradiation submodule and the fuel service performance submodule based on the actual irradiation results of the reactor and the mapping relationship between the actual irradiation results of the reactor and the simulation results of the material irradiation submodule and the fuel service performance submodule.

30. A method for verifying reactor design, characterized in that, It includes the following steps: The obtained reactor design parameters are input into the numerical reactor according to any one of claims 1-29; The numerical reactor operates according to the design parameters and obtains operating results; The results are compared with the expected results to determine whether the design parameters meet the expected design goals.

31. A method for predicting reactor operation, characterized in that, It includes the following steps: Obtain the current actual operating data of the reactor; The current actual operating data is input into the numerical reactor according to any one of claims 1-29; The numerical reactor operates according to the current actual operating data and obtains the operating results at a predetermined time in the future; Based on the obtained operating results, the future operating status of the reactor is predicted.

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