A method and device for establishing a corrosion model of a metal uranium material in a hydrogen environment based on a finite element method, and a storage medium

Abstract

The application discloses a method and device for establishing a corrosion model of metal uranium material in a hydrogen environment based on a finite element method and a storage medium, and relates to the technical field of computer simulation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of computer simulation, and particularly relates to a method and device for establishing a corrosion model of a metal uranium material in a hydrogen environment based on a finite element method and a storage medium. BACKGROUND

[0002] Metal uranium material is an important strategic nuclear material and plays an irreplaceable role in the fields of national security and advanced fissile energy technology. However, the metal uranium material has high chemical activity and environmental sensitivity and is prone to strong corrosion reactions with environmental gases such as oxygen, hydrogen and water vapor. Among them, the hydrogen corrosion of the metal uranium material in the hydrogen-containing atmosphere environment is the most harmful, which can cause serious local damage and affect the function of the parts. However, the hydride of the metal uranium material is extremely active and reacts extremely fast with oxygen or water, and even burns, so it must be characterized in a high-vacuum environment, and even so, it is difficult to exclude the interference of oxygen. At the same time, the metal uranium material has high toxicity and radiation hazards, and the experimental conditions are harsh, long cycle, high consumption of materials, difficult and high risk. In summary, the current research on the material corrosion of the metal uranium in the hydrogen environment is affected by the physical and chemical properties of the material itself, and it is difficult to obtain sufficient information, so it is difficult to deeply understand the material corrosion process of the metal uranium in the hydrogen environment. SUMMARY

[0003] In view of the technical problems that the information acquisition of the material corrosion process of the metal uranium in the hydrogen environment is limited, the purpose of the present application is to provide a method and device for establishing a corrosion model of a metal uranium material in a hydrogen environment based on a finite element method and a storage medium.

[0004] In one aspect, the present application embodiment comprises a method for establishing a corrosion model of a metal uranium material in a hydrogen environment based on a finite element method, which comprises the following steps:

[0005] A two-dimensional symmetric uranium hydrogen corrosion geometric model is established; the two-dimensional symmetric uranium hydrogen corrosion geometric model comprises a metal uranium model, a hydrogen model and a uranium hydride model, the hydrogen model surrounds the metal uranium model, the uranium hydride model is located inside the metal uranium model, and each part in the two-dimensional symmetric uranium hydrogen corrosion geometric model is symmetrically distributed on a two-dimensional plane;

[0006] According to the material properties of the metal uranium, hydrogen and uranium hydride, a plurality of physical fields are set for the two-dimensional symmetric uranium hydrogen corrosion geometric model;

[0007] The two-dimensional symmetric uranium hydrogen corrosion geometric model is meshed;

[0008] The values of each physical field in each grid are coupled and solved.

[0009] Further, the establishing the two-dimensional symmetric uranium-hydrogen corrosion geometric model comprises:

[0010] acquiring actual sizes of the metal uranium sample and the uranium hydride sample;

[0011] proportionally establishing the two-dimensional symmetric uranium-hydrogen corrosion geometric model according to the actual sizes of the samples.

[0012] Further, the setting multiple physical fields for the two-dimensional symmetric uranium-hydrogen corrosion geometric model according to material properties of the metal uranium, hydrogen and the uranium hydride comprises:

[0013] setting a chemical reaction physical field; the chemical reaction physical field comprises a chemical equation

[0014] 2U(s)+3H2(g)→2UH3(s)

[0015] the reaction type of the chemical equation is an irreversible reaction, and the rate constant of the chemical equation is

[0016] k=A(T / T ref ) n e -E / RT

[0017] wherein A represents a reaction frequency factor, E represents an activation energy of the chemical reaction, R represents a universal gas constant, and T represents an environmental temperature.

[0018] Further, the setting multiple physical fields for the two-dimensional symmetric uranium-hydrogen corrosion geometric model according to material properties of the metal uranium, hydrogen and the uranium hydride comprises:

[0019] setting a gas diffusion physical field; the gas diffusion physical field comprises a gas diffusion equation

[0020]

[0021] wherein c is the concentration of hydrogen in the metal uranium, S is the diffusion flux of hydrogen in the metal uranium, D is the diffusion coefficient of hydrogen in the metal uranium, and t is time.

[0022] Further, the setting multiple physical fields for the two-dimensional symmetric uranium-hydrogen corrosion geometric model according to material properties of the metal uranium, hydrogen and the uranium hydride comprises:

[0023] setting a solid mechanics stress physical field; the solid mechanics stress physical field comprises a strain equation

[0024]

[0025] and a constitutive equation

[0026]

[0027] Among them, c UH3 is the surface concentration of uranium hydride generated by metallic uranium, M UH3 is the molar mass of uranium hydride, ρ UH3 is the density of diffused UH3, r UH3 is the radius of the initial nucleation site of the uranium hydride model, ε represents the strain tensor of the metallic uranium, σ represents the stress tensor, E represents the elastic modulus matrix of the metallic uranium, and d represents the scalar damage degree of the metallic uranium.

[0028] Furthermore, meshing the two-dimensional symmetric uranium-hydrogen corrosion geometric model includes:

[0029] Meshing the metallic uranium model and the hydrogen model at a first mesh density;

[0030] The uranium hydride model is meshed with a second mesh density; the second mesh density is greater than the first mesh density.

[0031] Furthermore, the coupling solution of the numerical values ​​of each physical field in each grid includes:

[0032] Coupled solving is performed on the numerical values ​​of each non-solid mechanics stress physical field in each grid; the non-solid mechanics stress physical field is a physical field other than the solid mechanics stress physical field in all the set physical fields;

[0033] Based on the solution results of each of the non-solid mechanics stress physical fields, a coupled solution is performed on the numerical values ​​of the solid mechanics stress physical field in each grid.

[0034] Furthermore, the shape of the metal uranium model is cylindrical.

[0035] On the other hand, an embodiment of the present invention also includes a computer device, including a memory and a processor, the memory is used to store at least one program, and the processor is used to load at least one program to execute the method of establishing a metal uranium material corrosion model in a hydrogen environment based on the finite element method in the embodiment.

[0036] On the other hand, an embodiment of the present invention also includes a computer-readable storage medium, which stores a program executable by a processor. When the program executable by the processor is executed by the processor, it is used to execute the method of establishing a metal uranium material corrosion model in a hydrogen environment based on the finite element method in the embodiment.

[0037] The beneficial effects of the present invention are as follows: the method for establishing a corrosion model of metal uranium materials in a hydrogen environment based on the finite element method in the embodiment can obtain the corrosion process of metal uranium materials in a hydrogen environment in real time without conducting experiments on physical samples such as metal uranium and hydrogen, thereby improving experimental efficiency, shortening test time, and achieving effective and reliable prediction results under the conditions of limited experiments, controllable risks, less time and investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of the steps of a method for establishing a corrosion model of a metallic uranium material in a hydrogen environment based on the finite element method in an embodiment;

[0039] Figure 2 A schematic diagram of a two-dimensional symmetric uranium-hydrogen corrosion geometric model and its mesh division in an embodiment;

[0040] Figure 3 This is a schematic diagram of the change in surface concentration of uranium hydride over time during the corrosion process in a hydrogen environment obtained by solving the two-dimensional symmetric uranium-hydrogen corrosion geometric model in the embodiment;

[0041] Figure 4 Schematic diagram of the distribution of hydrogen transfer into the metal uranium matrix at different times obtained by solving the two-dimensional symmetric uranium-hydrogen corrosion geometric model;

[0042] Figure 5 Schematic diagram of the three-dimensional stress distribution and numerical magnitude during the growth of metallic uranium hydride obtained to solve the two-dimensional symmetric uranium-hydrogen corrosion geometric model;

[0043] Figure 6 Schematic diagram of the damage distribution of the metallic uranium substrate during the growth of metallic uranium hydride obtained to solve the two-dimensional symmetric uranium-hydrogen corrosion geometric model. DETAILED DESCRIPTION

[0044] The hydrogen corrosion of uranium metal is accompanied by the formation of corrosion products (hydrides), the formation and growth of new phase nuclei, and a complex process that progresses from microscopic quantitative changes to macroscopic qualitative changes. Due to the unique characteristics of uranium metal and the stringent experimental conditions, basic data on hydrogen corrosion behavior, corrosion mechanisms, and influencing factors are not comprehensive, making the development of new corrosion-resistant uranium alloys inefficient. Computer simulation is a highly effective method for studying the hydrogen corrosion behavior of uranium metal, and numerical experiments can be considered to evaluate the hydrogen corrosion behavior and mechanisms of uranium materials.

[0045] Based on the above principles, this embodiment provides a method for establishing a corrosion model of metal uranium material in a hydrogen environment based on the finite element method. Figure 1 The method for establishing a corrosion model of metallic uranium material in a hydrogen environment based on the finite element method includes the following steps:

[0046] S1. Establish a two-dimensional symmetric uranium-hydrogen corrosion geometric model;

[0047] S2. According to the material properties of the metal uranium, hydrogen gas and uranium hydride, set multiple physical fields for the two-dimensional symmetric uranium-hydrogen corrosion geometric model;

[0048] S3. Perform meshing on the two-dimensional symmetric uranium-hydrogen corrosion geometric model;

[0049] S4. Couplingly solve the numerical values of each physical field in each mesh.

[0050] In step S1, the two-dimensional symmetric uranium-hydrogen corrosion geometric model established can be expressed in an array or the like, and its specific form can be multiple coordinates of points in a space, and each coordinate respectively corresponds to a material type (metal uranium, hydrogen gas or uranium hydride) and parameters such as material density, molar mass, Poisson's ratio, Young's modulus, surface property, surface reaction rate, diffusion coefficient and diffusion molar flow. The two-dimensional symmetric uranium-hydrogen corrosion geometric model includes a metal uranium model, a hydrogen gas model and a uranium hydride model, etc. The coordinate points in the metal uranium model represent that the substance at the corresponding coordinates in the space is metal uranium, the coordinate points in the hydrogen gas model represent that the substance at the corresponding coordinates in the space is hydrogen gas, and the coordinate points in the uranium hydride model represent that the substance at the corresponding coordinates in the space is uranium hydride. In the two-dimensional symmetric uranium-hydrogen corrosion geometric model, the hydrogen gas model surrounds the metal uranium model, and the uranium hydride model is located inside the metal uranium model.

[0051] The two-dimensional symmetric uranium-hydrogen corrosion geometric model established in step S1 can be meshed in step S3. The space in the same mesh has the same coordinates, material type and other parameters.

[0052] Each part of the two-dimensional symmetric uranium-hydrogen corrosion geometric model established in step S1 is symmetrically distributed on a two-dimensional plane. For example, any two-dimensional plane can be obtained from the two-dimensional symmetric uranium-hydrogen corrosion geometric model along a direction parallel to a reference plane, and a symmetric point can be found in this two-dimensional plane. The density (the number of meshes contained in a unit volume / area) of the meshes, the material type and other parameters of the meshes at the same distance from the symmetric point on this two-dimensional plane correspond to each other, respectively.

[0053] When step S1, that is, the step of establishing a two-dimensional symmetric uranium-hydrogen corrosion geometric model, is performed, the following steps can be performed:

[0054] S101. Obtain the actual sample size of the metal uranium sample and the uranium hydride sample;

[0055] S102. According to the actual sample size, establish a two-dimensional symmetric uranium-hydrogen corrosion geometric model in proportion.

[0056] In step S101, the metal uranium sample and the uranium hydride sample are physical samples that require a simulated corrosion process. For example, the metal uranium sample is a cylinder with a diameter of 8 mm and a height of 4 mm, and the uranium hydride sample is a sphere with a diameter of 0.1 mm. In step S102, a two-dimensional symmetric uranium-hydrogen corrosion geometric model can be established based on the actual size of the samples at a 1:1 ratio. That is, in the two-dimensional symmetric uranium-hydrogen corrosion geometric model, the metal uranium model is a cylinder with a diameter of 8 mm and a height of 4 mm, the initial value of the uranium hydride model is a sphere with a diameter of 0.1 mm located at the center of the metal uranium model, and the hydrogen model is located on the periphery of the metal uranium model.

[0057] In this embodiment, the bottom surface of the cylindrical metal uranium model is used as the reference plane, and a part of the two-dimensional symmetrical uranium-hydrogen corrosion geometric model is obtained. Figure 2 As shown in part (a) of Figure 2 After meshing part (a) into multiple grids, Figure 2 As shown in part (b) of .

[0058] Figure 2 In parts (a) and (b), the horizontal axis represents the radius and the vertical axis represents the height. The vertical axis corresponds to the central axis of the cylindrical metal uranium model, and the horizontal axis corresponds to a radius parallel to the bottom surface of the cylindrical metal uranium model.

[0059] In this embodiment, when executing step S2, that is, setting multiple physical fields for the two-dimensional symmetric uranium-hydrogen corrosion geometric model based on the material properties of metallic uranium, hydrogen, and uranium hydride, the following steps can be performed using finite element calculation software:

[0060] (1) Define the material properties of metallic uranium, uranium hydride, and hydrogen at each location (coordinate or grid) in the two-dimensional symmetric uranium-hydrogen corrosion geometric model, and input the basic parameters such as density, molar mass, Poisson's ratio, and Young's modulus of metallic uranium, uranium hydride, and hydrogen at each location. The material properties of metallic uranium and uranium hydride are solid, and the material property of hydrogen is gas.

[0061] (2) Set the chemical reaction physics field. The chemical reaction physics field can define the reaction equation, reaction object, reaction rate, substances involved in the reaction, etc. to describe the corrosion of metal uranium and hydrogen. Enter the reaction equation in the chemical reaction physics field.

[0062] 2U(s)+3H2(g)→2UH3(s)

[0063] The reaction type of the chemical equation is an irreversible reaction, and the reaction rate is determined based on the law of mass action. Specifically, the rate constant of the chemical equation is

[0064] k=A(T / T ref )n e -E / RT

[0065] Where k represents the rate constant, A represents the reaction frequency factor, E represents the activation energy of the chemical reaction, R represents the universal gas constant, and T represents the ambient temperature. For each position in the two-dimensional symmetric uranium-hydrogen corrosion geometric model, the basic physical properties such as the molar mass and density of the corresponding reactants and reaction products are input respectively, such as the molar mass of metallic uranium U is 238.02891 g / mol, the molar mass of hydrogen H2 is 2 g / mol, the molar mass of uranium hydride UH3 is 241.05285 g / mol, and the density is 10.92 g / cm 3 .

[0066] (3) Further define the surface properties, initial values, surface reaction rates, and other parameters of each surface involved in the corrosion in the two-dimensional symmetric uranium-hydrogen corrosion geometric model. For example, the boundary material transport is selected as the streamline diffusion method, the number of surface materials in the dependent variable is 2, the surface material concentration includes the surface material concentration of metal uranium U and the surface material concentration of uranium hydride UH3, the number of bulk materials is 1, and the bulk concentration includes the bulk concentration of hydrogen H2. The initial values ​​are defined as follows: the diffusion coefficient of the surface material is 0, the surface concentration of the initial corroded metal uranium U is set to 122.1 mol / m2, the surface concentration of uranium hydride UH3 is 0, and the bulk concentration of hydrogen H2 is 0.

[0067] (4) Set up the gas diffusion physical field, which can define the diffusion surface, diffusion coefficient, and diffusion molar flow rate of hydrogen in the metal uranium. Based on Fick's law, the diffusion process of hydrogen in the metal uranium matrix is ​​described, and the diffusion component diffuses from the high concentration area to the low concentration area, so that the gas diffusion equation can be used.

[0068]

[0069] To represent the gas diffusion physics field. Where c is the concentration of hydrogen in uranium metal, S is the diffusion flux of hydrogen in uranium metal, D is the diffusion coefficient of hydrogen in uranium metal, and t is time. The diffusion coefficient of hydrogen H2 is set to 10 -9 m 2 / s, hydrogen H 2的 Normal inward flux is 10 -10 mol / (m 2 ·s), set the axisymmetric interface.

[0070] (5) Set the solid mechanics stress physics field, which can define the stress effect on the metal uranium matrix during the growth of uranium hydride. Define the Poisson's ratio, Young's modulus and density of the linear elastic materials of metal uranium U and uranium hydride UH3 respectively, and the strain is calculated by the strain equation

[0071]

[0072] To define, where c UH3 is the surface concentration of uranium hydride generated by metallic uranium, M UH3 is the molar mass of uranium hydride, ρ UH3 is the density of diffused UH3, r UH3 is the radius of the initial nucleation site of the uranium hydride model, ε represents the strain tensor of the metal uranium, and the initial strain is 0. Based on the classical damage theory, a scalar damage model is used to represent the damage of the metal uranium model. Specifically, due to the characteristic stress-strain behavior of ductile metal materials when they are damaged, the damage is manifested in two forms: softening of yield stress and degradation of elasticity. Metal uranium is regarded as a ductile metal material. Then the elastic modulus of metal uranium can be represented by E(1-d), where E represents the elastic modulus matrix of metal uranium, and d represents the scalar damage degree of metal uranium. d is a scalar representing the isotropic damage degree. When d is 0, it means that the metal uranium is undamaged, d is 1, it means that the metal uranium is completely damaged, and d between 0 and 1 means that the metal uranium is partially damaged. Based on the smoothed Rankine stress equivalent strain, the constitutive equation can be established.

[0073]

[0074] Here, σ represents the stress tensor.

[0075] When performing meshing in step S3, since the reaction process simulated by the two-dimensional symmetric uranium-hydrogen corrosion geometric model is the reaction between hydrogen H2 and metallic uranium U, the generated uranium hydride UH3 will damage the metallic uranium matrix. Therefore, the situation at the uranium hydride model can be focused on. The metallic uranium model and the hydrogen model can be meshed with a lower first mesh density, and the uranium hydride model can be meshed with a higher second mesh density. That is, in the two-dimensional symmetric uranium-hydrogen corrosion geometric model, a denser mesh is used for the uranium hydride model. In this embodiment, the maximum mesh size (e.g., side length) for the two-dimensional symmetric uranium-hydrogen corrosion geometric model is 0.04 mm, and the minimum mesh size is 3×10 -4 mm, the maximum cell growth rate of the grid is 1.05, the curvature factor is 0.25, and the resolution in narrow areas is 1.

[0076] In step S4, the solver in the finite element calculation software is set to "transient", and the time unit, output time step, and research object are set to consider the above chemical reaction equation, surface reaction, solid mechanics, solid transfer, etc. The solver time unit is set to s, the output time step is output once every 2s, the end is 200s, the absolute tolerance is 0.005, and the tolerance factor is 0.05. In this embodiment, an implicit solver is used to calculate the solution through the backward difference formula.

[0077]

[0078] The full coupling method is selected to perform time stepping to solve the numerical value of each physical field at each grid in each time step. Among them, is a difference operator, and f(k) is the numerical value distribution (numerical value at each grid) of any parameter (such as material type, material density, molar mass, etc.) in any physical field at the kth time step.

[0079] In this embodiment, when performing step S4, that is, coupling and solving the numerical value of each physical field at each grid, the following steps can be performed:

[0080] S401. Coupling and solving the numerical value of each non-solid mechanics stress physical field at each grid;

[0081] S402. Based on the solution result of each non-solid mechanics stress physical field, coupling and solving the numerical value of the solid mechanics stress physical field at each grid.

[0082] The non-solid mechanics stress physical field in step S401 refers to the physical field other than the solid mechanics stress physical field among all the physical fields set in step S2. Therefore, steps S401-S402 are to first coupling and solve all the physical fields other than the solid mechanics stress physical field, and then solve the solid mechanics stress physical field based on the coupling and solving result of these physical fields. The result of performing steps S401-S402 is the numerical value distribution (such as the numerical value at each grid) of the parameters such as material type, material density, and molar mass.

[0083] In this embodiment, the principle of performing steps S401-S402 is that, because the density difference between uranium hydride UH3 and metal uranium U is large, the uranium hydride model will produce volume expansion and stress effect on the metal uranium model representing the metal uranium matrix in the reaction process simulated by the two-dimensional symmetric uranium hydrogen corrosion geometric model, the concentration of chemical substance transfer will affect the solid mechanics in the form of external stress, and the solid mechanics will not affect the substance diffusion and chemical reaction; therefore, when coupling and solving the two-dimensional symmetric uranium hydrogen corrosion geometric model, all the physical fields other than the solid mechanics stress physical field can be solved first, and then the solid mechanics stress physical field is solved separately, and when solving the solid mechanics stress physical field, the previously calculated concentration and probe result are called to realize one-way multi-physical field coupling. Compared with coupling and solving all the physical fields including the solid mechanics stress physical field at the same time, the solution mode of steps S401-S402 is more stable in calculation, and the convergence and solution speed can be improved.

[0084] Steps S1-S4, a two-dimensional symmetric uranium hydrogen corrosion geometric model is established as a metal uranium material corrosion model in a hydrogen environment, and the two-dimensional symmetric uranium hydrogen corrosion geometric model is solved based on the finite element method to obtain the surface concentration of the metal uranium material hydride, the distribution of the hydrogen diffusion speed and other parameters, thereby obtaining the specific numerical information of the real-time changes of the uranium hydride nucleation and growth process, stress distribution, damage condition and other physical quantities. This method is simple, feasible, convenient to apply and reliable in results. The corrosion process of the metal uranium material in the hydrogen environment can be obtained in real time. Compared with physical experiments which are high in cost, high in risk, long in period and multiple in results, digital experiments can greatly improve the experimental efficiency, shorten the test time and achieve effective and reliable prediction results under the conditions of limited experiments, controllable risks, less time and investment. The digital experiments can further reveal the influence of external factors on the corrosion behavior and the corrosion mechanism which are ignored in macroscopic experiments, and provide reliable data and model support for monitoring and predicting the service life of weapons and equipment.

[0085] In steps S1-S4, by establishing a two-dimensional symmetric uranium hydrogen corrosion geometric model as a metal uranium material corrosion model in a hydrogen environment, due to the two-dimensional symmetric characteristics of the two-dimensional symmetric uranium hydrogen corrosion geometric model, the calculation amount can be reduced and the coupled solution can be more easily converged when the grid around the uranium hydride model is very dense, which can accurately describe the process of the increasing stress on the metal uranium substrate caused by the increasing uranium hydride, thereby causing the deformation of the metal uranium substrate.

[0086] In this embodiment, the results of steps S1-S4 are visualized, and the effect is as shown in Figure 3-Figure 6 .

[0087] When the two-dimensional symmetric uranium hydrogen corrosion geometric model is coupled and solved for each physical field, the numerical distribution output of the surface concentration of the uranium hydride UH3 at each time step is obtained, and the surface concentration diagram of the uranium hydride UH3 changing with time is obtained as shown in Figure 3 . Referring to Figure 3 , the growth rate of the surface concentration of the uranium hydride UH3 is slow in the initial stage and is in the nucleation incubation period, and then increases rapidly. Figure 4 Part (a) of FIG. 8 shows the amount of hydrogen gas in the hydrogen gas model in the two-dimensional symmetric uranium hydrogen corrosion geometric model being transported into the metal uranium model representing the metal uranium substrate at a time step of 2s, Figure 4 Part (b) of FIG. 8 shows the amount of hydrogen gas in the hydrogen gas model in the two-dimensional symmetric uranium hydrogen corrosion geometric model being transported into the metal uranium model representing the metal uranium substrate at a time step of 200s, Figure 4 The color in FIG. 8 indicates that the numerical value gradually increases from blue to red, the hydrogen gas diffuses from each outer surface of the metal uranium to the inside, the overall transport amount is small at the beginning, and a concentration gradient is formed at 200s, which diffuses from the periphery to the center.

[0088] Figure 5 The three-dimensional stress distribution and numerical value of each position (each grid) of the two-dimensional symmetric uranium-hydrogen corrosion geometric model are shown in the process of hydride growth of metallic uranium material simulated by the coupled solution of the two-dimensional symmetric uranium-hydrogen corrosion geometric model. Figure 5 Part (a) is the stress distribution at the initial 0s, and the maximum stress is 3.5×10 -91 N / m2, tends to 0; Figure 5 Part (b) shows the stress distribution at 200s, with the maximum stress being 7×10 7 N / m2. It can be seen that as the uranium hydride model representing uranium hydride UH3 is continuously generated, the stress on the metal uranium model representing the metal uranium matrix increases significantly. Figure 5 Part (c) shows that when the stress accumulates to a certain level, the strong stress causes bulges on the surface of the metal uranium model, thereby simulating the formation of the "hydrogen bubbling" phenomenon, which is consistent with the experimental results of the actual sample.

[0089] Figure 6 The figure shows the damage distribution of the metal uranium model representing the metal uranium matrix during the growth of metal uranium material hydride simulated by the coupled solution of the two-dimensional symmetric uranium-hydrogen corrosion geometric model. The damage to the metal uranium model is represented by the scalar damage degree d, which has a dimension of 1. Figure 6 Part (a) shows the damage distribution at the initial 0s. Figure 6 Part (b) shows the damage distribution at 120s. Figure 6 Part (c) shows the damage distribution at 200s. Figure 6 It can be seen that the coupled solution of the two-dimensional symmetric uranium-hydrogen corrosion geometric model successfully simulates the corrosion process of hydrogen on metallic uranium: initially, no uranium hydride UH3 is generated, that is, no stress is generated, and no damage is caused to the metallic uranium matrix. However, as the hydrogen H2 outside the metallic uranium matrix diffuses into the metallic uranium matrix, uranium hydride UH3 is continuously generated, the stress on the metallic uranium matrix gradually increases, and the damage to the metallic uranium matrix by hydrogen H2 becomes stronger and stronger, and even the surface of the metallic uranium matrix is ​​strongly damaged.

[0090] The above results show that the method, device and storage medium of the present invention for establishing a corrosion model of metal uranium materials in a hydrogen environment based on the finite element method can realize digital experiments on the corrosion behavior of metal uranium materials in a hydrogen-containing environment, and provide reliable data and model support for monitoring and predicting the degree of corrosion of weapons and equipment.

[0091] The corrosion simulation of the metal uranium material in the hydrogen environment in steps S1-S4 is a general method. In practical application, the initial conditions such as the material type (for example, uranium niobium alloy, uranium titanium alloy, etc.), temperature, concentration, and boundary conditions can be changed, and the above steps can still be operated by replacing the relevant parameters in the corresponding positions. The simulation conditions are controllable, the calculation efficiency is high, the results are intuitive and clear, and the analysis is convenient.

[0092] The computer program for executing the method for establishing the corrosion model of the metal uranium material in the hydrogen environment based on the finite element method in the embodiment can be written into a computer device or a storage medium. When the computer program is read out and run, the method for establishing the corrosion model of the metal uranium material in the hydrogen environment based on the finite element method in the embodiment is executed, thereby realizing the same technical effect as the method for establishing the corrosion model of the metal uranium material in the hydrogen environment based on the finite element method in the embodiment.

[0093] It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it can be directly fixed or connected to the other feature, or indirectly fixed or connected to the other feature. In addition, the up, down, left, right and the like used in the disclosure are only relative to the relative position relationship of the components of the disclosure in the drawings. In the disclosure, the singular forms "a", "an" and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. In addition, unless otherwise defined, all technical and scientific terms used in the embodiments have the same meanings as those commonly understood by those skilled in the art. The terms used in the embodiments are only used to describe the specific embodiments, and are not intended to limit the present application. The term "and / or" used in the embodiments includes any combination of one or more related listed items.

[0094] It should be understood that although the terms first, second, third, etc. can be used in the disclosure to describe various elements, these elements should not be limited to these terms. These terms are only used to distinguish elements of the same type from each other. For example, without departing from the scope of the disclosure, the first element can also be referred to as the second element, and similarly, the second element can also be referred to as the first element. The use of any and all examples or exemplary language (for example, "for example", "for example", etc.) provided in the embodiments is only intended to better illustrate the embodiments of the present application, and unless otherwise required, does not impose a limitation on the scope of the present application.

[0095] It should be appreciated that embodiments of the present application can be implemented or realized in a computing hardware, a combination of hardware and software, or by computer instructions stored on a non-transitory computer readable storage medium. The methods can be implemented using standard programming techniques - including the configuration of a non-transitory computer readable storage medium with computer program instructions stored thereon, wherein the storage medium is configured such that it causes a computer to operate in a specific and predefined manner as described in the various embodiments and figures according to the methods described in the various embodiments. Each program can be implemented in a high level procedural or object oriented programming language to communicate with a computer system. However, the programs can be implemented in assembly or machine language, if desired. In any case, the language can be a compiled or interpreted language. Furthermore, the programs can be able to operate with a specific dedicated integrated circuit that is programmed to perform the methods described in the various embodiments.

[0096] Further, the operations of the processes described in the various embodiments can be performed in any suitable order, unless otherwise indicated herein or otherwise clearly contradicted by context. The processes described in the various embodiments (or variations and / or combinations thereof) can be implemented under the control of one or more computer systems configured with executable instructions (e.g., computer programs, one or more computer programs, or one or more applications), hardware, or combinations thereof. The computer programs include machine instructions that can be executed by one or more processors.

[0097] Further, the methods can be implemented in any suitable type of computing platform operably connected to any suitable type of computing platform, including but not limited to a personal computer, a mini-computer, a mainframe, a workstation, a network or distributed computing environment, a stand-alone or integrated computer platform, or in communication with a charged particle tool or other imaging device, etc. Aspects of the present application can be implemented in machine readable code stored on a non-transitory storage medium or device, whether removable or integrated into the computing platform, such as a hard disk, an optically readable and / or writeable storage medium, RAM, ROM, etc., such that it can be read by a programmable computer to configure and operate the computer to perform the processes described herein when the storage medium or device is read by the computer. Further, the machine readable code, or portions thereof, can be transmitted over a wired or wireless network. The present application includes these and other different types of non-transitory computer readable storage media when the instructions or programs implementing the above steps are included in conjunction with a microprocessor or other data processor. The present application also includes the computer itself when programmed according to the methods and techniques of the present application.

[0098] The computer program can be applied to input data to perform the functions of the present embodiment, thereby converting the input data to generate output data that is stored in a non-volatile memory. The output information can also be applied to one or more output devices such as a display. In a preferred embodiment of the present invention, the converted data represents a physical and tangible object, including a specific visual depiction of the physical and tangible object produced on the display.

[0099] The above are merely preferred embodiments of the present invention. The present invention is not limited to the aforementioned embodiments. As long as the technical effects of the present invention are achieved by the same means, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention. Within the scope of protection of the present invention, various modifications and variations of the technical solutions and / or implementation methods may be made.

Claims

1. A method for establishing a corrosion model of metallic uranium material in a hydrogen environment based on the finite element method, characterized in that: The method for establishing a corrosion model of a metallic uranium material in a hydrogen environment based on the finite element method includes: Establishing a two-dimensional symmetric uranium-hydrogen corrosion geometric model; the two-dimensional symmetric uranium-hydrogen corrosion geometric model includes a metal uranium model, a hydrogen model, and a uranium hydride model, the hydrogen model surrounds the metal uranium model, the uranium hydride model is located inside the metal uranium model, and each part of the two-dimensional symmetric uranium-hydrogen corrosion geometric model is symmetrically distributed on a two-dimensional plane; According to the material properties of metallic uranium, hydrogen and uranium hydride, multiple physical fields are set for the two-dimensional symmetric uranium-hydrogen corrosion geometric model; Meshing the two-dimensional symmetric uranium-hydrogen corrosion geometric model; Performing coupled solutions on the numerical values ​​of each physical field in each grid; The meshing of the two-dimensional symmetric uranium-hydrogen corrosion geometric model includes: Meshing the metallic uranium model and the hydrogen model at a first mesh density; Meshing the uranium hydride model with a second mesh density, wherein the second mesh density is greater than the first mesh density; The coupled solution of the numerical values ​​of each physical field in each grid includes: Coupled solving of the numerical values ​​of each non-solid mechanics stress physical field in each grid; the non-solid mechanics stress physical field is the physical field other than the solid mechanics stress physical field in all the set physical fields; Based on the solution results of each of the non-solid mechanics stress physical fields, a coupled solution is performed on the numerical values ​​of the solid mechanics stress physical field in each grid.

2. The method for establishing a corrosion model of metallic uranium material in a hydrogen environment based on the finite element method according to claim 1, characterized in that: The establishment of a two-dimensional symmetric uranium-hydrogen corrosion geometric model includes: Obtain the actual sample size of metallic uranium samples and uranium hydride samples; According to the actual size of the sample, the two-dimensional symmetrical uranium-hydrogen corrosion geometric model is established in proportion.

3. The method for establishing a corrosion model of metallic uranium material in a hydrogen environment based on the finite element method according to claim 1, characterized in that: According to the material properties of metallic uranium, hydrogen and uranium hydride, multiple physical fields are set for the two-dimensional symmetric uranium-hydrogen corrosion geometric model, including: Set the chemical reaction physical field; the chemical reaction physical field includes the chemical equation in, Represents metallic uranium, represents hydrogen, represents uranium hydride, Represents a solid, represents gas; the reaction type of the chemical equation is irreversible reaction, and the rate constant of the chemical equation is k = A ( T / T ref ) n e -E / RT Where A represents the reaction frequency factor, E represents the activation energy of the chemical reaction, R represents the universal gas constant, and T represents the ambient temperature.

4. The method for establishing a corrosion model of metallic uranium material in a hydrogen environment based on the finite element method according to claim 3, characterized in that: According to the material properties of metallic uranium, hydrogen and uranium hydride, multiple physical fields are set for the two-dimensional symmetric uranium-hydrogen corrosion geometric model, including: Setting the gas diffusion physics field; the gas diffusion physics field includes the gas diffusion equation in, c is the concentration of hydrogen in uranium metal, S is the diffusion flux of hydrogen in metallic uranium, D is the diffusion coefficient of hydrogen in metallic uranium, t For time.

5. The method for establishing a corrosion model of metallic uranium material in a hydrogen environment based on the finite element method according to claim 4, characterized in that: According to the material properties of metallic uranium, hydrogen and uranium hydride, multiple physical fields are set for the two-dimensional symmetric uranium-hydrogen corrosion geometric model, including: Set up a solid mechanics stress physical field; the solid mechanics stress physical field includes the strain equation and constitutive equation in, is the surface concentration of uranium hydride produced by metallic uranium, is the molar mass of uranium hydride, is the density of diffused UH3, is the radius of the initial nucleation site of the uranium hydride model, represents the strain tensor of metallic uranium, represents the stress tensor, E represents the elastic modulus matrix of metallic uranium, d Represents the scalar damage of metallic uranium.

6. The method for establishing a corrosion model of metallic uranium material in a hydrogen environment based on the finite element method according to any one of claims 1 to 5, characterized in that: The shape of the metal uranium model is cylindrical.

7. A computer device, characterized in that: The method comprises a memory and a processor, wherein the memory is used to store at least one program, and the processor is used to load at least one program to execute the method for establishing a metal uranium material corrosion model in a hydrogen environment based on the finite element method as described in any one of claims 1 to 6.

8. A computer-readable storage medium storing a program executable by a processor, characterized in that: The program executable by the processor is used to execute the method for establishing a metal uranium material corrosion model in a hydrogen environment based on the finite element method as described in any one of claims 1 to 6 when executed by the processor.

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