Numerical reactor, method for verifying reactor design and method for predicting

Abstract

The embodiment of the invention relates to the technical field of numerical simulation of reactors, in particular to a numerical reactor, a method for verifying the design of the reactor by using the numerical reactor and a method for predicting the operation of the reactor, and the numerical reactor comprises a physical thermal structure module which is set to simulate a neutron field, a temperature field and a stress field between reactor cores of the reactor; the fuel material module is arranged to simulate the organizational structure change of the fuel of the reactor in the fission process and the organizational structure change of the material; and the coupling module is configured to couple the neutron field, the temperature field and the stress field of the fuel material module according to the neutron field, the temperature field and the stress field of the physical thermal structure module, and is configured to couple the neutron field, the temperature field and the stress field of the physical thermal structure module according to the organizational structure change of the material and the fuel of the fuel material module. The numerical reactor disclosed by the embodiment of the invention is beneficial to ensuring the accuracy and reliability of the determined organization structure change of the fuel and the material and the neutron field, the temperature field and the stress field between the reactor cores.

Description

Technical Field

[0001] The implementation of the present application relates to the technical field of reactor numerical simulation, and specifically to a numerical reactor, a method for verifying reactor design using the numerical reactor, and a method for predicting reactor operation. Background Art

[0002] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0003] In the current field of nuclear energy utilization, nuclear reactor engineering is a complex project involving multiple disciplines such as neutron physics, thermal fluid, system analysis, mechanics, and radiation effects. It usually requires the use of research tools to study and analyze it, among which numerical reactors are an important research tool. Numerical reactors play a key role in deeply understanding the physical characteristics of nuclear reactors, optimizing designs, and ensuring the safe operation of nuclear reactors.

[0004] However, current numerical reactors face many challenges in practical applications. Due to the complexity and uncertainty of the reactor system, the established numerical reactors are often of low accuracy and it is difficult to fully and accurately reflect the actual operation of the reactor. For example, in the invention patent with publication number CN117454627A, a numerical reactor nuclear-heat-material coupling simulation method based on a unified grid is disclosed. This method integrates neutron physics, flow heat transfer and material corrosion models to achieve unified solution of the three physical processes under the same solver, so as to be used for high-fidelity simulation of the multi-physical processes of the nuclear reactor core. This method comprehensively considers the impact of the oxidation corrosion of the cladding material itself on the safety of the reactor, but does not involve the mutual influence between the performance changes of the cladding material before and after irradiation and the service performance changes of the fuel before and after service, and it is difficult to ensure the accuracy of the determined cladding material corrosion. Summary of the invention

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

[0006] In the first aspect, an embodiment of the present application provides a numerical reactor, which includes: a physical thermal structure module, which is configured to simulate the neutron field, temperature field and stress field between the reactor core; a fuel material module, which is configured to simulate the organizational structure changes of the reactor fuel during the fission process, and the organizational structure changes of the material; a coupling module, which is configured to couple the neutron field, temperature field and stress field of the fuel material module according to the neutron field, temperature field and stress field of the physical thermal structure module, and is configured to couple the organizational structure changes of the material and fuel of the fuel material module to the neutron field, temperature field and stress field of the physical thermal structure module.

[0007] The embodiments of the present application perform multi-scale simulations through a physical thermal structure module and a fuel material module, and couple the simulation results through a coupling module. The neutron field, temperature field and stress field of the fuel material module can be determined based on the determined neutron field, temperature field and stress field. At the same time, the neutron field, temperature field and stress field of the physical thermal structure module can also be determined based on the neutron field, temperature field and stress field of the fuel material module, thereby ensuring the accuracy and reliability of the final determined organizational structure changes of the fuel during the fission process, the organizational structure changes of the material, and the neutron field, temperature field and stress field between the reactor cores.

[0008] On the second aspect, an embodiment of the present application also provides a method for verifying a reactor design, wherein the design parameters of the reactor are input into a numerical reactor of an embodiment of the present application; the numerical reactor operates according to the parameters and obtains operating results; the operating results are compared with expected results to determine whether the design parameters meet the expected design goals.

[0009] On the third aspect, an embodiment of the present application also provides a method for predicting reactor operation, obtaining the current actual operating data of the reactor; inputting the current actual operating data into the numerical reactor of the embodiment of the present application; the numerical reactor operates according to the current actual operating data, and obtains the operating results at a predetermined time in the future; and predicting the future operating status of the reactor based on the obtained operating results.

[0010] These and other advantages of the present application will become more apparent through the following detailed description of the preferred embodiments of the present application in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0013] Figure 2 yes Figure 1 A specific structural schematic diagram of the numerical reactor shown;

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

[0015] Figure 4 is a schematic diagram of modifying parameters of a material irradiation submodule and a fuel service performance submodule according to an embodiment of the present application;

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

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

[0018] Figure 7 is a schematic flow chart of a method for verifying a reactor design according to an embodiment of the present application;

[0019] Figure 8 It is a schematic flow chart of a method for predicting reactor operation according to an embodiment of the present application.

[0020] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding.

[0021] Description of reference numerals:

[0022] 10. Physical thermal structure module;

[0023] 20. Fuel material module; 21. Material irradiation submodule; 211. Material neutron field; 212. Material stress field; 213. Material temperature field; 22. Fuel service performance submodule;

[0024] 30. Coupling module;

[0025] 40. Neutron physics module;

[0026] 50. Data driven module; 51. Mapping relationship;

[0027] 60. Verification module;

[0028] 71. Measured data; 72. Prior knowledge of physics. DETAILED DESCRIPTION

[0029] Exemplary embodiments of the present application will be described below in conjunction with the accompanying drawings. For the sake of clarity and conciseness, not all features of the actual implementation are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the process of developing any such actual implementation in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and these constraints may vary from implementation to implementation. In addition, it should be understood that although the development work may be very complex and time-consuming, it is only a routine task for those skilled in the art who benefit from the content of this application.

[0030] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, only the device structure and / or processing steps closely related to the scheme according to the present application are shown in the accompanying drawings, while other details that are not very relevant to the present application are omitted.

[0031] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in this application should have the common meanings understood by persons with ordinary skills in the field to which this application belongs.

[0032] In the description of the embodiments of the present application, “plurality” means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0033] The embodiment of the present application provides a numerical reactor, Figure 1 is a schematic diagram of the structure of a numerical reactor according to an embodiment of the present application, such as Figure 1 As shown, the numerical reactor may at least include a physical thermal structure module 10 , a fuel material module 20 and a coupling module 30 .

[0034] The physical thermal structure module 10 is configured to simulate the neutron field, temperature field and stress field between the reactor cores.

[0035] The fuel material module 20 is configured to simulate the structural changes of the fuel of the reactor during the fission process, as well as the structural changes of the material.

[0036] The coupling module 30 is configured to couple the neutron field, temperature field and stress field of the fuel material module 20 according to the neutron field, temperature field and stress field of the physical thermal structure module 10, and is configured to couple the neutron field, temperature field and stress field of the physical thermal structure module 10 according to the material of the fuel material module 20 and the organizational structure changes of the fuel.

[0037] The embodiments of the present application perform multi-scale simulations through a physical thermal structure module 10 and a fuel material module 20, and couple the simulation results through a coupling module 30. The neutron field, temperature field and stress field of the fuel material module 20 can be determined based on the determined neutron field, temperature field and stress field. At the same time, the neutron field, temperature field and stress field of the physical thermal structure module 10 can also be determined based on the neutron field, temperature field and stress field of the fuel material module 20, thereby ensuring the accuracy and reliability of the final determined structural changes of the fuel during the fission process, the structural changes of the material, and the neutron field, temperature field and stress field between the reactor cores.

[0038] In some embodiments, the neutron field, temperature field and stress field of the physical thermal structure module 10 are coupled to the neutron field, temperature field and stress field of the fuel material module 20 in the following manner:

[0039] Φ f (r,t+Δt)=f φ (T f (r,t),σ f (r,t),Φ c (r,t));

[0040] T f (r,t+Δt)=f T (T f (r,t),σ f (r,t),Φ f (r,t),T c (r,t));

[0041] σ f (r,t+Δt)=f σ (T f (r,t),σ f (r,t),Φ f (r,t),σ c (r,t)).

[0042] Among them, Φ c (r, t) represents the neutron field between the cores of the physical thermal structure module 10; T c (r, t) represents the temperature field between the cores of the physical thermal structure module 10; σ c (r, t) represents the stress field between the cores of the physical thermal structure module 10; Φ f (r, t) represents the neutron field of the fuel material module 20; T f (r, t) represents the temperature field of the fuel material module 20; σ f (r, t) represents the stress field of the fuel material module 20; φ f(r, t+Δt) represents the neutron field of the fuel material module 20 after coupling; T f (r,t+Δt) represents the temperature field of the fuel material module 20 after coupling; σ f (r, t+Δt) represents the stress field of the fuel material module 20 after coupling; r represents the spatial coordinate, where r≤r c , r c represents the coordinates of the outer boundary of the reactor cladding; t represents time; Δt represents the time increment in the iterative calculation; f φ represents a function for solving the neutron field of the fuel material module 20 by numerical method; f T represents a function for solving the temperature field of the fuel material module 20 by numerical method; f σ It represents a function for solving the stress field of the fuel material module 20 by numerical method.

[0043] The embodiment of the present application utilizes 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 above-mentioned manner. The coupling effect is good, which is conducive to ensuring the accuracy of the determined neutron field, temperature field and stress field of the fuel material module 20.

[0044] In some embodiments, Figure 2 yes Figure 1 A specific structural diagram of the numerical reactor shown in FIG. Figure 1 As shown, 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 performance of the material due to the changes in the organizational structure of the reactor material after irradiation; the fuel service performance submodule 22 is configured to simulate the changes in the organizational structure of the fuel in the reactor during the fission process.

[0045] The embodiment of the present application can improve the accuracy and reliability of the final determined material performance changes and the fuel service performance by performing simulation based on multiple scales through the material irradiation submodule 21 and the fuel service performance submodule 22.

[0046] In some embodiments, the coupling module 30 is also configured to couple the service performance of the fuel according to the changes in the material's organizational structure, and to couple the performance of the material according to the changes in the fuel's organizational structure. The service performance of the fuel can be determined based on the changes in the material's organizational structure, and the performance of the material can be determined based on the changes in the fuel's organizational structure, so as to improve the accuracy and reliability of the ultimately determined service performance of the fuel and the performance of the material.

[0047] In some embodiments, the neutron field, temperature field, and stress field of the fuel material module 20 and the organizational structure of the fuel meet the following expressions:

[0048] 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)).

[0049] Among them, G f (r,t+Δt) represents the organizational structure of the fuel after coupling; f Gf represents the function of solving the organizational structure of the fuel by numerical method; φ f (r, t) represents the neutron field of the fuel material module 20; T f (r, t) represents the temperature field of the fuel material module 20; σ f (r, t) represents the stress field of the fuel material module 20; G f (r, t) represents the organizational structure of the fuel at time t; G m (r,t) represents the organizational structure of the material at time t; Δt represents the time increment in the iterative calculation.

[0050] In some embodiments, the neutron field, temperature field, stress field and material structure of the fuel material module 20 conform to the following expressions:

[0051] 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)).

[0052] Among them, G m (r,t+Δt) represents the organizational structure of the material after coupling; f Gm Represents the function of solving the material structure by numerical method; Φ f (r, t) represents the neutron field of the fuel material module 20; T f (r, t) represents the temperature field of the fuel material module 20; σ f (r, t) represents the stress field of the fuel material module 20; G f (r, t) represents the organizational structure of the fuel at time t; G m (r,t) represents the organizational structure of the material at time t; Δt represents the time increment in the iterative calculation.

[0053] In some embodiments, the change in the material properties includes: changes in the macroscopic mechanical properties or geometric integrity properties of the material; Figure 2 As shown, 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 the service performance of the fuel according to the changes in the macroscopic mechanical properties or geometric integrity properties of the material.

[0054] The embodiment of the present application utilizes the material irradiation submodule 21 to determine the changes in the macroscopic mechanical properties or geometric integrity properties of the material and transmits them to the fuel service performance submodule 22, so that the fuel service performance submodule 22 can correct the changes in the service performance of the fuel according to the changes in the macroscopic mechanical properties or geometric integrity properties of the material, thereby more accurately determining the service performance of the fuel during the service process.

[0055] In some embodiments, when the material irradiation submodule 21 performs the function of simulating and determining the change in the macroscopic mechanical properties or geometric integrity properties of the material and transmitting it to the fuel service performance submodule 22, and when the fuel service performance submodule 22 performs the function of correcting the change in the service performance of its fuel according to the change in the macroscopic mechanical properties or geometric integrity properties of the material, the execution can be looped until a first predetermined time period is reached.

[0056] In some embodiments, the service performance of the fuel includes fission performance and fission product behavior, the fission performance includes temperature and stress distribution, and the fission product behavior includes gaseous fission product behavior and solid fission product behavior; wherein, Figure 2 As shown, 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.

[0057] The embodiment of the present application utilizes the fuel service performance submodule 22 to determine the temperature and stress distribution of the fuel, gaseous fission products and solid fission products and transmits them to the material irradiation submodule 21, so that the material irradiation submodule 21 can 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, and can more accurately determine the performance of the material after irradiation.

[0058] In some embodiments, when the fuel service performance submodule 22 performs the function of transferring the temperature and stress distribution, gaseous fission products and solid fission products of the fuel 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, gaseous fission products and solid fission products of the fuel, the execution can be looped until a second predetermined time period is reached.

[0059] In such an embodiment, the first predetermined duration and the second predetermined duration may be the same.

[0060] In some embodiments, the coupling module 30 is specifically configured to couple the service performance of the fuel according to changes in the macroscopic mechanical properties or geometric integrity properties of the material to ensure the reliability of the obtained service performance of the fuel.

[0061] In some embodiments, the coupling module 30 is specifically configured to couple the macroscopic mechanical properties or geometric integrity properties of the material according to the temperature and stress distribution of the fuel, gaseous fission products and solid fission products to ensure the reliability of the obtained macroscopic mechanical properties or geometric integrity properties of the material.

[0062] In some embodiments, Figure 2 As shown, 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 of the material under its irradiation and temperature; the material stress field 212 and the material temperature field 213 are configured to simulate the changes of the material under its stress and temperature; wherein the coupling module 30 is configured to couple the performance changes of the material according to the simulation results of the material neutron field 211, the material stress field 212, and the material temperature field 213.

[0063] The embodiment of the present application simulates the changes in the material under the material neutron field 211, the material stress field 212, and the material temperature field 213, and couples the simulation results using the coupling module 30, which is conducive to further improving the accuracy of determining material changes.

[0064] In some embodiments, Figure 2 As shown, the numerical reactor may also include a neutron physics module 40 for calculating the power density, nuclide distribution, etc. inside the fuel pellet.

[0065] In some embodiments, the input of the material neutron field 211 comes from the output of the neutron physics module 40 .

[0066] In some embodiments, the input of the material stress field 212 is derived from the output of the fuel service performance submodule 22 .

[0067] In some embodiments, the input of the material temperature field 213 comes from the output of the fuel service performance submodule 22 .

[0068] In some embodiments, the coupling module 30 couples the material neutron field 211, the material stress field 212 and the material temperature field 213 of the material irradiation submodule 21 by changing the generation, diffusion and aggregation process of point defects in the material during service; the coupling module 30 is specifically 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; obtain a third concentration of point defects under the material stress field 212 and the material temperature field 213.

[0069] The embodiment of the present application 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 aggregation process of point defects of the material during service, and the coupling effect is relatively good.

[0070] In some embodiments, 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, 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 neutron field 211 and the material temperature field 213 satisfy the following expression:

[0071] C=C1+C2-C0.

[0072] Among them, C represents the total concentration of point defects under the coupling of material neutron field 211, material stress field 212 and 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 neutron field 211 and the material temperature field 213; C2 represents the third concentration of point defects under the material stress field 212 and the material temperature field 213.

[0073] In some embodiments, the coupling module 30 is also specifically used to: obtain a first diffusion coefficient of a point defect under a material temperature field 213; obtain a second diffusion coefficient of a point defect under a material neutron field 211 and a material temperature field 213; and obtain a third diffusion coefficient of a point defect under a material stress field 212 and a material temperature field 213.

[0074] In some embodiments, the second diffusion coefficient of the point defect under the material neutron field 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 neutron field 211 and the material temperature field 213, and the first concentration of the point defect under the material temperature field 213 satisfy the following expressions:

[0075]

[0076] Among them, D1 represents the second diffusion coefficient of point defects under the material neutron field 211 and the material temperature field 213; D0 represents the first diffusion coefficient of point defects under the material temperature field 213; C1 represents the second concentration of point defects under the material neutron field 211 and the material temperature field 213; C0 represents the first concentration of point defects under the material temperature field 213.

[0077] In some embodiments, the defect diffusion coefficient under the coupling of the material neutron field 211, the material stress field 212, and the material temperature field 213, the third diffusion coefficient of the point defects under the material stress field 212 and the material temperature field 213, the total concentration of the point defects, and the third concentration of the point defects under the material stress field 212 and the material temperature field 213 satisfy the following expressions:

[0078]

[0079] Among them, D represents the defect diffusion coefficient under the coupling of material neutron field 211, material stress field 212 and material temperature field 213; D2 represents the third diffusion coefficient of point defects under the material stress field 212 and material temperature field 213; C represents the total concentration of point defects under the coupling of material neutron field 211, material stress field 212 and material temperature field 213; C2 represents the third concentration of point defects under the material stress field 212 and material temperature field 213.

[0080] In some embodiments, the coupling module 30 is further specifically used to control the evolution of defects using the control equation of defect reaction under the material neutron field 211, the material stress field 212 and the material temperature field 213, and the control equation is:

[0081]

[0082] Where i, j and k represent defects of different sizes; G i represents the generation term of point defect i, which is input by 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 control equation represents the increase term from defect j to defect i, and the third term represents the decomposition, absorption, and disappearance term from defect i; C i represents the concentration of defects i in the material; C j represents the concentration of defects j in the material; Ci-j Indicates the concentration of defects ij in the material; C k-i Indicates the concentration of defects ki in the material; D i represents the diffusion coefficient of defect i in the material; D j represents the diffusion coefficient of defect j in the material; D i-j represents the diffusion coefficient of the defect ij in the material; D k-i represents the diffusion coefficient of the defect ki in the material; the concentration of the defect C i , C i-j , C k-i and the diffusion coefficient D i , D i -j , D k-i It is obtained by coupling under the material neutron field 211, the material stress field 212 and the material temperature field 213 respectively; wherein, 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 change of the macroscopic mechanical properties or geometric integrity properties of the material is determined based on the defect distribution function.

[0083] 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 changes in the temperature distribution of the fuel during a fission reaction; the stress distribution unit is configured to simulate changes in the stress distribution of the fuel during a fission reaction; the microstructure evolution unit is configured to simulate changes in the microstructure of the fuel during a fission reaction; the fission gas behavior unit is configured to simulate changes in the amount of gas released into the gas cavity and caused by fission gas produced in the fission reaction of the fuel; and the solid fission product behavior unit is configured to simulate changes in the distribution of solid fission products produced in the fission reaction of the fuel.

[0084] The embodiment of the present application sets 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 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, with high reliability.

[0085] In some embodiments, the numerical reactor may further include a thermal hydraulic module for simulating the thermal hydraulics of the reactor and determining the coolant pressure of the reactor and the temperature distribution on the outer surface of the fuel rod cladding.

[0086] In some embodiments, the input of the temperature distribution unit comes from the output of the neutron physics module and the thermal hydraulic module.

[0087] In some embodiments, the input of the stress distribution unit comes from the output of the neutron physics module and the thermal hydraulic module.

[0088] In some embodiments, the input of the microstructure evolution unit comes from the output of the neutron physics module.

[0089] In some embodiments, the input to the fission gas behavior unit is derived from the output of the neutron physics module.

[0090] In some embodiments, the input of the solid fission product unit is derived from the output of the neutron physics module.

[0091] In some embodiments, the coupling module 30 is further configured to couple changes in fission gas behavior, solid fission product behavior, microstructure evolution, fuel stress field and fuel temperature field to obtain changes in the internal composition, structure, thermal conductivity and geometric integrity of the fuel.

[0092] In some embodiments, by coupling the temperature distribution unit, stress distribution unit, microstructure evolution unit, fission gas behavior unit and 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 22 are determined.

[0093] In some embodiments, the coupling module 30 is specifically configured to: during the coupling process, the temperature and stress distribution of the fuel during service and the changes in the microstructure, fission gas and solid fission product behavior are updated at predetermined time intervals in the order in which the temperature distribution unit, the stress distribution unit, the microstructure evolution unit, the fission gas behavior unit, and the solid fission product behavior unit are simulated in sequence.

[0094] In some embodiments, the temperature distribution unit is specifically configured to: use a three-dimensional heat conduction equation to describe the distribution of the temperature of the fuel in a predetermined space, wherein the three-dimensional heat conduction equation is:

[0095]

[0096] Wherein, T represents the temperature of the fuel; t represents the time; Indicates the coordinates of a certain point of the fuel rod in the predetermined space; c v represents the heat capacity per unit volume; q represents the volume heat release rate; It represents the thermal conductivity of the fuel, which is related to the internal chemical composition and microstructure of the fuel.

[0097] In some embodiments, the microstructure evolution unit is specifically configured to: describe the change of the microstructure of the fuel in the fission reaction to obtain the structural information of the microstructure, wherein the change of the microstructure includes chemical composition, phase structure, grain size and morphology, and porosity; wherein the evolution of non-conserved order parameters and conserved order parameters of the phase structure, grain size, morphology, and porosity is controlled by a predetermined evolution equation, and the predetermined evolution equation is:

[0098]

[0099] in, The non-conserved order parameter representing phase structure, grain size, morphology and porosity; L i (g, T, σ) represents the diffusion mobility of the non-conserved order parameter of the fuel; F represents the free energy equation of the fuel; c i J represents the conserved order parameters of phase structure, grain size, morphology and porosity; T represents the temperature-driven diffusion flux; J c represents the diffusion flux driven by free energy; M 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.

[0100] In some embodiments, the predetermined evolution equations may be reaction-diffusion (Allen-Cahn) and Cauchy (Cahn-Hilliard) equations.

[0101] In some embodiments, the microstructure information of the fuel can be obtained by calculating the microstructure evolution unit, which is denoted as g, and includes the fuel phase structure str, the element composition c in the fuel, and the fuel grain size r. g , fuel grain boundary morphology geo g And the information of porosity p. Among them, the fuel microstructure information g satisfies the following expression:

[0102] g=f g (str,c,r g ,geo g ,p)+g fis .

[0103] Among them, g fis It represents the microstructural changes caused by solid fission products, which can be used as an input parameter for the behavior of gaseous and solid fission products in fission reactions.

[0104] In some embodiments, the fission gas behavior unit is specifically configured to describe the transmission, induced swelling and release amount of fission gas in the fuel to obtain the distribution of fission gas within the crystal, on the grain boundary and on the crystal edge, the release amount of fission gas, the induced swelling and the porosity distribution, wherein the fission gas includes xenon and krypton.

[0105] In some embodiments, the distribution of fission gas in the crystal, on the grain boundary and on the crystal edge, and the amount of fission gas released satisfy the following expression:

[0106]

[0107] Among them, w rea represents the amount of fission gas released; t represents the service time of the fuel; q(g,T,σ) represents the migration coefficient of the crystal surface bubble to the crystal edge; C f represents the bubble concentration on the grain boundary; P represents the bubble release coefficient on the crystal edge; C e represents the bubble concentration on the crystal edge; n(g,T,σ) represents the direct release coefficient of bubbles on the crystal surface.

[0108] In some embodiments, the distribution of fission gas within the crystal, on the grain boundary and on the crystal edge, and the swelling caused by the fission gas satisfy the following expression:

[0109]

[0110] Where, ΔV α Indicates swelling caused by fission gases; r i Indicates the radius of the bubble of size i.

[0111] In some embodiments, based on the distribution of fission gas within the crystal, on the grain boundary and on the crystal edge, the porosity distribution of the fuel satisfies the following expression:

[0112]

[0113] in, Indicates the porosity distribution of the fuel; represents the distribution of initial fuel void fraction; P'(r i ) represents the void fraction distribution caused by fission gas.

[0114] In some embodiments, the fission gas may be xenon (Xe) or krypton (Kr), among others.

[0115] In some embodiments, the fission gas behavior unit mainly considers the generation of fission gas during the fission process. The gas diffuses through the fuel grains, bubbles form and coalesce and grow, diffuse to the grain boundaries, and stay in the fuel to cause the fuel to swell. Then, as the fuel consumption increases, the bubbles on the crystal interface will connect to form a fission gas release channel, and the fission gas will be released into the gap between the fuel and the cladding. The atomic concentration of fission gas in the fuel C g , the bubble concentration inside the grain C b , Bubble concentration on grain boundary C f , and the bubble concentration C on the crystal edge e Mainly dominated by the bubble evolution governing equation:

[0116]

[0117] Where a(g,T,σ) represents the bubble nucleation coefficient; b(g,T,σ) represents the bubble absorption coefficient; D g represents the gas diffusion coefficient; d g represents the grain diameter; s represents the amount of gas generated; e(g,T,σ) represents the intracrystalline bubble re-dissolution coefficient; h(g,T,σ) represents the crystal face (or crystal edge) bubble re-dissolution coefficient; l(g,T,σ) represents the grain boundary absorption bubble 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 coefficient to the crystal edge; P represents the crystal edge bubble release coefficient; N b Indicates the average number of bubbles in a grain; N f Indicates the average number of bubbles on the crystal surface; N e represents the number of bubbles in the grain; r represents the distance from the center of the grain inside the grain, that is, r in the spherical coordinate system; t represents the evolution time.

[0118] In some embodiments, by solving the above bubble evolution control equation, the distribution of fission gas in the crystal, on the grain boundary and on the crystal edge can be obtained, and the release amount of fission gas w rea , the swelling caused by ΔV α , and the porosity distribution

[0119] In some embodiments, the solid fission product behavior unit is specifically configured to: describe the behavior of solid fission products produced by the fission process to determine the precipitation phase, migration behavior and spatial distribution of the solid fission products of the fuel, wherein the behavior of the solid fission products includes the behavior of strontium, cesium, iodine and lanthanum / actinide fission products, and the behavior of the solid fission products can be controlled by a predetermined evolution equation of an embodiment of the present application.

[0120] In some embodiments, the solid fission product precipitation phase, migration behavior and spatial distribution of the fuel solid fission product can be obtained by calculating the solid fission product behavior unit, which is denoted as g fis . It contains the fuel precipitation phase structure information str fis-pre , concentration distribution C fis , and the diffusion of solid fission products in the fuel D fis , where the migration behavior and distribution in space g fis Satisfies the following expression:

[0121] g fis =f g-fis (str fis-pre ,C fis ,D fis ).

[0122] Among them, f g-fis Represents the function for solving the behavior of solid fission products in fuel by numerical method.

[0123] In some embodiments, the coupling module 30 is further configured to: simulate the fuel temperature distribution determined by the fuel service performance submodule 22 Stress distribution The amount of fission gas released w rea and the distribution of solid fission products g fis It is passed to the material irradiation submodule 21 to perform multi-scale simulation based on the material and update the radiation damage behavior of the material under new temperature, stress, fission gas and solid fission conditions, thereby improving the accuracy of the changes in the macroscopic mechanical properties or geometric integrity properties of the material obtained by simulation.

[0124] In some embodiments, the coupling module 30 is further configured to: change the mechanical properties of the material by g fis , geometric integrity parameter Δε c , and the microstructural defect distribution N i =f(d i ,t) is transmitted to the temperature distribution unit, stress distribution unit and microstructure evolution unit in the fuel service performance submodule 22 to update the service performance of the fuel, thereby improving the accuracy of the simulated service performance changes of the fuel.

[0125] In some embodiments, Figure 3 is a schematic diagram of the structure of a numerical reactor according to another embodiment of the present application. Figure 3 As shown, the numerical reactor also includes a data driving module, which is configured to determine a mapping relationship between the actual irradiation result of the reactor and the simulation result of the material irradiation submodule 21 and the simulation result of the fuel service performance submodule 22.

[0126] In some embodiments, Figure 3 As shown, the numerical reactor also 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 simulation results of the fuel service performance submodule 22.

[0127] The numerical reactor provided in the embodiment of the present application verifies the accuracy of the service performance of the fuel and materials through the verification module 60 according to the actual irradiation results of the reactor, 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, so as to facilitate the correction of the parameters of the numerical reactor to make the calculation results of the numerical reactor more accurate and reliable, and at the same time avoid the situation where the actual irradiation result data of the reactor is insufficient.

[0128] In some embodiments, the actual irradiation results of the reactor may include measured data of the reactor and prior physical knowledge.

[0129] In some embodiments, the data driving module 50 is obtained in the following manner: obtaining measured data and prior physical knowledge of the reactor, the measured data including the temperature, pressure, flow, neutron flux, and power distribution of the reactor; determining the data driving module 50 for cross-scale multi-physical feature fusion based on the measured data and prior physical knowledge; and correcting the parameters of the data driving module 50 according to the output results of the data driving module 50 as well as the measured data and prior physical knowledge.

[0130] The data driving module 50 obtained by the method provided in the embodiment of the present application is conducive to ensuring that the data driving module 50 follows physical laws when fusing features of different scales and has high reliability.

[0131] Figure 4 is a schematic diagram of modifying the parameters of the material irradiation submodule 21 and the fuel service performance submodule 22 according to an embodiment of the present application, such as Figure 4 As shown, on the one hand, the parameters of the material irradiation submodule 21 and the fuel service performance submodule 22 can be directly corrected using the measured data 71 and the prior physical knowledge 72; on the other hand, according to the mapping relationship 51 determined by the data driving module, the parameters of the material irradiation submodule 21 and the fuel service performance submodule 22 can be indirectly corrected.

[0132] In some embodiments, the measured data 71 may include experimental data, actual operation data of the reactor, etc. When collecting the measured data 71, not only the macroscopic operation parameters of the reactor are focused on, but also the interrelated data at different scales can be collected through multi-scale experimental equipment and measurement methods.

[0133] In some embodiments, the measured data 71 of the reactor may include, but are not limited to, key parameters such as temperature, pressure, flow rate, neutron flux, power distribution, etc. In order to ensure the diversity and representativeness of the data, the measured data 71 may correspond to the reactor status under different operating conditions and different working conditions.

[0134] In some embodiments, the collected measured data 71 may be cleaned to remove abnormal values ​​and erroneous data contained therein. For example, the collected measured data 71 may be denoised, and filtering or other methods may be used to reduce the impact of measurement noise on the data, thereby improving the quality of the data. For another example, the collected measured data 71 may be normalized so that data of different parameters are at the same level, which is convenient for subsequent analysis and processing.

[0135] Figure 5 is a schematic diagram of the verification process of the verification module 60 according to an embodiment of the present application, such as Figure 5 As shown, the verification module 60 is used to execute the following steps S1 to S5.

[0136] S1. Constructing a calculation example, which includes: directly constructing a calculation example based on measured data 71 and prior physical knowledge 72; indirectly constructing a calculation example based on a mapping relationship 51 between the actual irradiation results of the reactor determined by the data driving module 50 and the simulation results of the material irradiation submodule 21 and the simulation results of the fuel service performance submodule 22.

[0137] S2, module operation, which includes: running the material irradiation submodule 21 and the fuel service performance submodule 22 based on the directly constructed examples and the indirectly constructed examples to obtain the simulation results of the material irradiation submodule 21 and the fuel service performance submodule 22.

[0138] S3, module analysis, which includes: comparative analysis to determine the differences and deficiencies of 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 has inaccurate calculations for certain specific types, and the module parameters need to be further optimized. By identifying the differences and deficiencies, the aspects that need to be corrected are determined.

[0139] 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. The adaptability and prediction ability of the module can be enhanced by adjusting the parameter value range, adding other key parameters or considering nonlinear relationships. In the optimization process, the trial and error method can be used to find a better parameter combination through multiple parameter adjustments and operations. Genetic algorithms can also be used to optimize module parameters. By simulating the biological evolution process, the optimal module parameter combination is found to minimize the error between the module prediction value and the measured data 71.

[0140] S5, module verification and evaluation, which includes: after the module parameter optimization is completed, 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 corrected material irradiation submodule 21 and fuel service performance submodule 22 are closer to the measured data 71.

[0141] In some embodiments, Figure 6 is a schematic diagram of multi-scale physical coupling according to an embodiment of the present application, such as Figure 6 As shown, a multi-scale physical coupling module can be constructed based on the neutron transport program, burnup program, thermal fluid calculation program, structural mechanics calculation program, fuel performance analysis program, and material performance analysis program of a single physical process, using a master-slave architecture. The multi-scale physical coupling module can be divided into a control layer, a drive layer, a data layer, and an execution layer according to functional requirements.

[0142] Based on the grid type and simulation parameters, the representation specifications and unified interface of grid data and parameters are established, which is conducive to saving storage resources and improving access efficiency; based on the efficient positioning data index and difference algorithm in different spatial discrete forms, efficient conversion and transfer of parameters are realized, which is conducive to improving coupling efficiency; based on the specific coupling calculation model, the mapping relationship of the coupling parameter transfer function is established51, which is conducive to improving the accuracy of coupling parameter transfer; based on the single-level and multi-level time step control methods, it is conducive to balancing the simulation accuracy and calculation time.

[0143] The embodiment of the present application also provides a method for verifying a reactor design. Figure 7 is a schematic flow chart of a method for verifying a reactor design according to an embodiment of the present application, such as Figure 7 As shown, it includes the following steps S10 to S30.

[0144] S10, inputting the obtained design parameters of the reactor into the numerical reactor of the embodiment of the present application.

[0145] S20. The numerical reactor operates according to the parameters and obtains the operating results.

[0146] S30: Compare the operation result with the expected result to determine whether the design parameters meet the expected design goals.

[0147] The method provided in the embodiment of the present application can verify the reactor design obtained by inputting the obtained reactor design parameters into the numerical reactor provided in the embodiment of the present application to check whether the reactor design values ​​meet the requirements, and modify the design values ​​according to the operation of the numerical reactor. Furthermore, the above numerical reactor is also suitable for verifying the materials of the reactor internal components, and further guiding the research and development of the materials in the reactor according to the verification results.

[0148] The embodiment of the present application also provides a method for predicting reactor operation. Figure 8 is a schematic flow chart of a method for predicting reactor operation according to an embodiment of the present application, such as Figure 8 As shown, it includes the following steps S40 to S70.

[0149] S40, obtaining current actual operation data of the reactor.

[0150] S50, inputting the current actual operation data into the numerical reactor of the embodiment of the present application.

[0151] S60: The numerical reactor operates according to the current actual operating data, and obtains the operating result at a predetermined time in the future.

[0152] S70. Predict the future operation status of the reactor based on the obtained operation results.

[0153] The method provided in the embodiment of the present application can use the data of the reactor currently in actual operation, input these data into the numerical reactor provided in the embodiment of the present application, and use the numerical reactor to operate based on these data, so that the data of the future reactor can be known, that is, the future operation of the actual reactor can be predicted. According to the predicted situation, the possible service situation of the reactor in the future can be judged, and safety measures can be taken in advance for special situations, thereby improving the reliability of the reactor operation.

[0154] It can be understood that there is no sequential order of execution between step S30 and step S40 in the embodiment of the present application.

[0155] Regarding the embodiments of the present application, it should also be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other to obtain new embodiments.

[0156] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. The protection scope of the present application shall be based on the protection scope of the claims.

Claims

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

2. The numerical reactor according to claim 1, characterized in that: The neutron field, temperature field and stress field of the physical thermal structure module are coupled to the neutron field, temperature field and stress field of the fuel material module 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)); Among them, 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 fuel material module after coupling; T f (r, t+Δt) represents the temperature field of the fuel material module after coupling; σ f (r, t+Δt) represents the stress field of the fuel material module after coupling; r represents the spatial coordinate, wherein r≤r c , r c represents the coordinates of the outer boundary of the cladding of the reactor; t represents time; Δt represents the time increment in the iterative calculation; f φ represents a function for solving the neutron field of the fuel material module by numerical method; f T represents a function for solving the temperature field of the fuel material module by numerical method; f σ A function representing a stress field of the fuel material module solved by a numerical method.

3. The numerical reactor according to claim 1, characterized in that: The fuel material module includes: material irradiation submodule and fuel service performance submodule; The material irradiation submodule is configured to simulate the change in the performance of the material caused by the change in the organizational structure of the material of the reactor after being irradiated; The fuel service performance submodule is configured to simulate the changes in the organizational structure of the fuel in the reactor during the fission process.

4. The numerical reactor according to claim 3, characterized in that: The coupling module is also configured to couple the service performance of the fuel according to changes in the organizational structure of the material, and to couple the performance of the material according to changes in the organizational structure 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 and the organizational structure 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 of the fuel material module and the organizational structure of the material 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 organizational structure of the fuel after coupling; G m (r, t+Δt) represents the organizational structure of the material after coupling; 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 organizational structure of the fuel at time t; G m (r, t) represents the organizational structure of the material at time t; Δt represents the time increment in the iterative calculation; f Gf represents a function for solving the organizational structure of the fuel by numerical method; f Gm It represents the function of solving the organizational structure of the material by numerical method.

6. The numerical reactor according to claim 3, characterized in that: The change in the performance of the material includes: a change in the macroscopic mechanical properties or geometric integrity properties of the material; 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 according to 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 fission performance and fission product behavior, The fission performance includes temperature and stress distribution, and the fission product behavior includes gaseous fission product behavior and solid fission product behavior; Wherein, the fuel service performance submodule is further configured to: transmit the temperature and stress distribution, gaseous fission products and solid fission products of the fuel determined by simulation to the material irradiation submodule; The material irradiation submodule is configured to determine 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 according to the change of the macroscopic mechanical properties or the 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 the geometric integrity properties of the material are coupled according to 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 material neutron field and the material temperature field are configured to simulate changes in the material under irradiation and temperature; The material stress field and the material temperature field are configured to simulate changes in the material under stress and temperature; Wherein, the coupling module is configured to couple the performance change of the material according to the simulation results of the material neutron field, the material stress field and the material temperature field.

11. The numerical reactor according to claim 10, characterized in that: The coupling module couples the material neutron field, material stress field and material temperature field of the material irradiation submodule by changing the generation, diffusion and aggregation process of point defects of the material during service; Wherein, the coupling module is specifically used for: Under the material temperature field, obtaining a first concentration of the point defects; Under the material neutron field and the material temperature field, obtaining a second concentration of the point defect; Under the material stress field and the material temperature field, a third concentration generating the point defects is obtained.

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

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

14. The numerical reactor according to claim 13, characterized in that: The second diffusion coefficient of the point defect under the material neutron field and the material temperature field, the first diffusion coefficient of the point defect under the material temperature field, the second concentration of the point defect under the material neutron field and the material temperature field, and the first concentration of the point defect under the material temperature field satisfy the following expressions: Among them, D1 represents the second diffusion coefficient of the point defect under the material neutron field and the material temperature field; D0 represents the first diffusion coefficient of the point defect under the material temperature field; C1 represents the second concentration of the point defect under the material neutron field and the material temperature field; C0 represents the first concentration of the point defect under the material temperature field.

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

16. The numerical reactor according to claim 15, characterized in that: The coupling module is further specifically used for: Under the material neutron field, material stress field and material temperature field, the defect evolution is controlled by using the control equation of defect reaction, and the control equation is: Where i, j and k represent defects of different sizes; G i represents the generation term of the point defect i, which is input by the neutron field of the material; K and n represent the defect reaction rate constant and reaction radius; the second term on the right side of the control equation represents the increase term from defect j to defect i, and the third term represents the decomposition, absorption and disappearance term from defect i; C i represents the concentration of defects i in the material; C j represents the concentration of defects j in the material; C i-j represents the concentration of defects ij in the material; C k-i represents the concentration of defects ki in the material; D i represents the diffusion coefficient of the defect i in the material; D j represents the diffusion coefficient of the defect j in the material; D i-j represents the diffusion coefficient of the defect ij in the material; D k-i represents the diffusion coefficient of the defect ki in the material; the concentration C of the defect i , C i-j , C k-i and the diffusion coefficient D i , D i-j , D k-i The coupling is obtained under the material neutron field, the material stress field and the material temperature field respectively; Among them, the defect distribution function of the material under the coupling of the material neutron field, the material stress field and the material temperature field is determined based on the evolution of the point defect; the change of the macroscopic mechanical properties or geometric integrity properties of the material is 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 change of the fuel temperature distribution during the fission reaction of the fuel; The stress distribution unit is configured to simulate changes in the fuel stress distribution of the fuel during the fission reaction; The microstructure evolution unit is configured to simulate the change of the microstructure of the fuel in the fission reaction; The fission gas behavior unit is configured to simulate the swelling of the fuel and the change in the amount of gas released into the gas cavity caused by the fission gas generated by the fuel in the fission reaction; The solid fission product behavior unit is configured to simulate the distribution change of the solid fission product generated by the fuel in the fission reaction in the fuel.

18. The numerical reactor according to claim 17, characterized in that: The coupling module is further configured to: The fission gas behavior, solid fission product behavior, microstructure evolution, fuel stress field and fuel temperature field changes are coupled to obtain 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 of the fuel during service and the changes in the microstructure, fission gas and solid fission product behavior are updated at predetermined time intervals in the order in which the temperature distribution unit, the stress distribution unit, the microstructure evolution unit, the fission gas behavior unit and the solid fission product behavior unit are simulated in sequence.

21. The numerical reactor according to claim 20, characterized in that The fission gas behavior unit is specifically configured to: describe the transmission, induced swelling and release amount of the fission gas in the fuel, so as to obtain the distribution of the fission gas in the crystal, on the grain boundary and on the crystal edge, the release amount of the fission gas, the induced swelling and the void fraction distribution; Wherein, the fission gas includes xenon and krypton.

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

23. The numerical reactor according to claim 22, characterized in that: The distribution of the fission gas in the crystal, on the grain boundary and on the crystal edge, and the porosity distribution of the fuel satisfy the following expression: in, representing the porosity distribution of the fuel; represents the distribution of initial fuel void fraction; (r i ) represents the void fraction distribution caused by fission gas.

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

25. The numerical reactor according to claim 20, characterized in that The coupling module is also configured to transmit the temperature distribution, stress distribution, fission gas release and solid fission product distribution of the fuel 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 and fission gas and solid fission conditions.

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

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

28. The numerical reactor according to claim 27, characterized in that The data driving module is obtained in the following manner: Acquiring measured data and prior physical knowledge of the reactor, wherein the measured data includes temperature, pressure, flow rate, neutron flux, and power distribution of the reactor; Based on the measured data and the prior physical knowledge, determining a data driving module for cross-scale multi-physical feature fusion; The parameters of the data driving module are modified according to the output result of the data driving module, the measured data, and the priori physical knowledge.

29. The numerical reactor according to claim 28, characterized in that Also includes the 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 simulation results of the fuel service performance submodule.

30. A method for verifying a reactor design, characterized in that: It includes the following steps: Inputting the obtained design parameters of the reactor into the numerical reactor according to any one of claims 1 to 29; The numerical reactor operates according to the design parameters and obtains operating results; The operating results are compared with 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: Obtaining current actual operation data of the reactor; Inputting the current actual operation data into the numerical reactor according to any one of claims 1 to 29; The numerical reactor operates according to the current actual operation data and obtains the operation result at a predetermined time in the future; The future operation status of the reactor is predicted based on the obtained operation results.

Images