Heat conduction analysis method and system, electronic equipment and storage medium

Abstract

The invention provides a heat conduction analysis method and system, and belongs to the technical field of heat conduction simulation, and the method comprises the steps: dividing a dispersion fuel into a preset number of cylinder regions, and building the spatial position coordinates of all fuel particles in each cylinder region; all spatial position coordinates are imported into finite element simulation software, and a geometric model containing fuel particles is established; setting calculation conditions of the geometric model; grid division is conducted on the geometric model, and fuel temperature distribution is calculated based on grid division and calculation conditions; and after the fuel temperature distribution passes the grid independence verification, extracting the highest temperature of the fuel and the average temperature of all the cylinder regions from the fuel temperature distribution. According to the method, the cylinder area is accurately divided, the spatial position coordinates of the fuel particles are established, and fine grid division of finite element simulation software and multi-layer material calculation condition setting are combined, so that accurate temperature distribution simulation in the fuel column of the high-temperature gas cooled reactor is realized, and the accuracy of fuel temperature distribution calculation is effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of thermal conductivity simulation technology, and in particular to a thermal conductivity analysis method, system, electronic equipment and storage medium. Background Art

[0002] In the fuel column of a high-temperature gas-cooled reactor, fuel particles are randomly dispersed in a graphite matrix with high thermal conductivity, among which TRISO coated particles are used as distributed internal heat sources, which are crucial in thermal design and safety analysis. In order to simplify the calculation, the fuel column is often approximated as a homogeneous material (such as a graphite column) for thermal conductivity analysis in the prior art to avoid complex geometric models and particle position coordinate generation processes. However, this method ignores the actual distribution of TRISO particles and the influence of their multilayer structural materials on the temperature distribution, especially the characteristics of each particle as a distributed internal heat source, resulting in a significant reduction in the simulation accuracy of the temperature distribution, and the inability to accurately reflect the actual temperature gradient and local hot spots in the fuel column. This lack of accuracy not only affects the temperature field calculation results of the fuel column, but also brings deviations to the overall thermal performance evaluation and safety analysis of the high-temperature gas-cooled reactor, especially when it is necessary to determine the maximum temperature of the fuel and the average temperature of different regions to meet the stability and safety of the reactor. This deviation will lead to unreliable design and analysis results.

[0003] Therefore, how to improve the accuracy of fuel temperature distribution calculation has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] The present invention provides a thermal conductivity analysis method, system, electronic equipment and storage medium, which are used to solve the defects in the prior art and effectively improve the accuracy of fuel temperature distribution calculation.

[0005] The present invention provides a thermal conductivity analysis method, comprising the following steps: Dividing the dispersed fuel into a preset number of cylindrical areas, and establishing the spatial position coordinates of all fuel particles in each of the cylindrical areas; Importing all the spatial position coordinates into finite element simulation software to establish a geometric model containing fuel particles; Setting calculation conditions of the geometric model; Meshing the geometric model, and calculating fuel temperature distribution based on the meshing and the calculation conditions; After the fuel temperature distribution is verified to be grid independent, the maximum fuel temperature and the average temperature of all cylinder areas are extracted from the fuel temperature distribution.

[0006] According to a thermal conductivity analysis method provided by the present invention, the step of dividing the dispersed fuel into a preset number of cylindrical areas specifically includes: Based on the preset number, the first radius of the dispersed fuel and the second radius of the fuel particles, the outer diameter of each cylindrical area is calculated; the outer diameter of each cylindrical area is calculated by the following formula: ; Wherein, k is the preset number, is the outer diameter of the i-th cylindrical zone, R is the first radius, and a is the second radius; The dispersed fuel is divided based on each of the outer diameters to obtain a preset number of cylindrical areas.

[0007] According to a thermal conductivity analysis method provided by the present invention, the step of establishing the spatial position coordinates of all fuel particles in each cylindrical area specifically includes: Calculating the volume of each of the cylindrical regions based on the preset number, each of the outer diameters, the first radius, and the second radius, and determining the number of all fuel particles in each of the cylindrical regions based on each of the volumes, wherein each of the numbers is linearly related to each of the volumes; Calculating the central cylindrical coordinates of each of the cylindrical areas based on the preset number, each of the outer diameters, the first radius, and the second radius; Based on each of the quantities and each of the volumes, all of the fuel particles in each of the cylindrical regions are evenly distributed on the central cylinder of each of the cylindrical regions, and based on each of the central cylinder coordinates, the spatial position coordinates of all of the fuel particles in each of the cylindrical regions are generated.

[0008] According to a thermal conductivity analysis method provided by the present invention, the number of all fuel particles in the first cylindrical area is 1; the volume of each cylindrical area is calculated based on the preset number, each outer diameter, the first radius and the second radius, and the number of all fuel particles in each cylindrical area is determined based on each volume, specifically including: The volume of each cylindrical area is calculated by the following formula: ; The number of all fuel particles in each cylindrical area is expressed by the following formula: ; in, is the volume of the i-th cylindrical region, is the outer diameter of the i-th cylindrical zone, is the outer diameter of the i-1th cylindrical area, R is the first radius, a is the second radius, and k is the preset number.

[0009] According to a thermal conductivity analysis method provided by the present invention, the central cylindrical coordinates of each cylindrical area are calculated based on the preset number, each outer diameter, the first radius and the second radius, specifically including: The central cylindrical coordinates of each cylindrical area are calculated by the following formula: ; in, is the central cylindrical coordinate of the i-th cylindrical area, is the outer diameter of the i-th cylindrical area, R is the first radius, a is the second radius, and k is the preset number.

[0010] According to a thermal conductivity analysis method provided by the present invention, the calculation conditions include thermal conductivity coefficients of various materials, internal heat source parameters and boundary conditions.

[0011] According to a thermal conductivity analysis method provided by the present invention, the method further comprises: After the fuel temperature distribution fails to pass the grid independence verification, the grid density is adjusted, and the steps of meshing the geometric model and calculating the fuel temperature distribution based on the meshing and the calculation conditions are re-executed until the fuel temperature distribution passes the grid independence verification.

[0012] The present invention also provides a thermal conductivity analysis system, comprising the following modules: A coordinate establishment module, used to divide the dispersed fuel into a preset number of cylindrical areas and establish the spatial position coordinates of all fuel particles in each of the cylindrical areas; A geometric model building module, used to import all the spatial position coordinates into finite element simulation software to build a geometric model containing fuel particles; A processing module, used for setting the calculation conditions of the geometric model; The processing module is further used to perform meshing on the geometric model and calculate the fuel temperature distribution based on the meshing and the calculation conditions; The processing module is also used to extract the maximum fuel temperature and the average temperature of all cylinder areas from the fuel temperature distribution after the fuel temperature distribution passes the grid independence verification.

[0013] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, any one of the above-mentioned thermal conductivity analysis methods is implemented.

[0014] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the thermal conductivity analysis method as described above is implemented.

[0015] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the thermal conductivity analysis method described above is implemented.

[0016] In summary, one or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: By dividing the dispersed fuel into a preset number of cylindrical areas and establishing the spatial position coordinates of all fuel particles in each cylindrical area, the uniform distribution of fuel particles in the fuel column is achieved, so that the fuel particle filling rate meets the preset design requirements, effectively ensuring the geometric accuracy of the model and providing a reliable basis for subsequent temperature field calculations. Then, all spatial position coordinates are imported into the finite element simulation software to establish a geometric model containing fuel particles. In this way, it is ensured that the geometric model of the fuel column can truly reproduce the actual physical structure, making the simulation model closer to the actual situation in structure. After the geometric model is established, the calculation conditions of the geometric model are set, including the thermal conductivity, internal heat source parameters and boundary conditions of each material, so as to ensure that the thermal conduction characteristics and internal heat source properties of each material layer in the model are truly reflected, and the temperature field distribution of the actual fuel column can be accurately simulated, avoiding errors caused by simplified processing. Then, the geometric model is finely meshed, and the fuel temperature distribution is calculated based on the meshing and the set calculation conditions. Through this refined grid division and comprehensive calculation condition setting, the temperature distribution calculation can capture the temperature gradient changes at different material layers and interfaces in the fuel column, and realize high-precision simulation of the heat conduction process of the fuel column. Finally, after the temperature distribution calculation is completed, the stability of the calculation results is ensured by grid independence verification, thereby eliminating the influence of grid division on the temperature field distribution. After verification, the maximum temperature of the fuel and the average temperature of each cylindrical area are extracted from the fuel temperature distribution. This extraction method can provide accurate temperature data, reflect the hot spot location and overall temperature distribution in the fuel column, and provide reliable temperature basic data for the thermal design and safety analysis of the high-temperature gas-cooled reactor. Through this overall solution, the accuracy of the fuel temperature distribution calculation can be effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is one of the flow diagrams of the thermal conductivity analysis method provided by the present invention.

[0019] Figure 2 It is a schematic diagram of the dispersed fuel with uniformly distributed fuel particles in the cylindrical area provided by the present invention.

[0020] Figure 3 This is the second flow chart of the thermal conductivity analysis method provided by the present invention.

[0021] Figure 4 It is a schematic diagram of the fuel finite element mesh provided by the present invention.

[0022] Figure 5 This is the third flow chart of the thermal conductivity analysis method provided by the present invention.

[0023] Figure 6 It is a structural schematic diagram of the thermal conductivity analysis system provided by the present invention.

[0024] Figure 7 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] It should be noted that, in the description of the present invention, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "include one..." do not exclude the existence of other identical elements in the process, method, article or device including the elements. The orientation or positional relationship indicated by the terms "upper", "lower", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the system or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0027] The terms "first", "second", etc. in the present invention are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present invention can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" means at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0028] Combine the following Figure 1-Figure 7 The present invention describes a thermal conductivity analysis method, system, electronic device and storage medium.

[0029] Figure 1 It is one of the flow diagrams of the thermal conductivity analysis method provided by the present invention, such as Figure 1 As shown, including but not limited to the following steps: Step 101: Divide the dispersed fuel into a preset number of cylindrical areas, and establish the spatial position coordinates of all fuel particles in each cylindrical area.

[0030] In the embodiment of step 101, please refer to Figure 2 , Figure 2 This is a schematic diagram of a dispersed fuel with uniform distribution of fuel particles in a cylindrical area provided by the present invention. In order to accurately simulate the temperature distribution in a high-temperature gas-cooled reactor fuel column and ensure the uniform distribution of fuel particles, the dispersed fuel is first divided into multiple cylindrical areas, and the spatial position coordinates of all fuel particles in each cylindrical area are established. The purpose of this is to solve the problem of inaccurate temperature distribution caused by the homogeneous approximate treatment of the fuel column in the prior art, and to ensure that the temperature distribution is closer to the actual situation through fine partitioning and position calculation, thereby improving the accuracy and reliability of the simulation.

[0031] The following embodiment will explain the specific implementation method of step 101 in detail.

[0032] In a possible implementation manner, in step 101, the method of dividing the dispersed fuel into a preset number of cylindrical areas specifically includes the following steps: Based on the preset number, the first radius of the dispersed fuel and the second radius of the fuel particles, the outer diameter of each cylindrical area is calculated; the outer diameter of each cylindrical area is calculated by the following formula: ; Among them, k is the preset number, is the outer diameter of the i-th cylindrical zone, R is the first radius, and a is the second radius; The dispersed fuel is divided based on each outer diameter to obtain a preset number of cylindrical zones.

[0033] Specifically, in the above steps, without considering the overflow of particles into the dispersed fuel, in order to achieve uniform distribution of fuel particles in the fuel column and ensure that the filling rate of each partition is consistent and close to the actual fuel column structure, the dispersed fuel is first divided into multiple cylindrical areas, and the outer diameter and spatial position coordinates of each cylindrical area are determined. The purpose of this is to make the temperature distribution calculation closer to the actual situation through reasonable area division and accurate geometric parameter calculation, thereby improving the simulation accuracy and reliability.

[0034] More specifically, first, according to the preset number of cylindrical zones, the first radius R of the dispersed fuel, and the second radius a of the fuel particles, the outer diameter of each cylindrical zone is calculated. The core of this step is to use the equal thickness design of the partitions, that is, to ensure that the thickness of each cylindrical zone in the radial direction is consistent, so as to achieve uniform distribution of the dispersed fuel. The outer diameter of each cylindrical zone is calculated according to the formula Calculate, where k is the preset number of partitions, is the outer diameter of the i-th cylindrical zone, R is the first radius of the dispersed fuel, that is, the total radius of the fuel column, and a is the radius of the fuel particles. This calculation method ensures the consistency of the inner and outer particle distribution of the dispersed fuel through segmented equal thickness partitions, thereby forming a series of nested cylindrical zones, so that each area from the inside to the outside is evenly filled with fuel particles, avoiding the aggregation or sparse distribution of fuel particles inside the fuel column.

[0035] After calculating the outer diameter of each cylindrical zone, the dispersed fuel is then divided based on these outer diameters to obtain a preset number of cylindrical zones. In the specific operation, the fuel column is divided from the inside to the outside according to each calculated outer diameter value, and is divided into multiple cylindrical zones with the same thickness. The thickness of each cylindrical zone remains consistent, ensuring that each partition covers the entire fuel column in an orderly and uniform manner in space. This division method makes the spatial distribution of fuel particles in each partition more reasonable, thereby achieving a uniform filling design of the fuel column. By dividing each cylindrical zone, it is ensured that the fuel particles are distributed in a spatial hierarchy within the fuel column, which is conducive to the subsequent precise control of the number and position of particles in each partition.

[0036] In one possible implementation, refer to Figure 3 , Figure 3 This is the second flow chart of the thermal conductivity analysis method provided by the present invention, such as Figure 3 As shown, in step 101, the method for establishing the spatial position coordinates of all fuel particles in each cylindrical area specifically includes steps 201-203: Step 201: Calculate the volume of each cylindrical area based on a preset number, each outer diameter, a first radius, and a second radius, and determine the number of all fuel particles in each cylindrical area based on each volume, wherein each number is linearly related to each volume.

[0037] In a possible implementation, in step 201, the volume of each cylindrical region is calculated by the following formula: ; The total number of fuel particles in each cylindrical area is expressed by the following formula: ; in, is the volume of the i-th cylindrical region, is the outer diameter of the i-th cylindrical zone, is the outer diameter of the i-1th cylindrical area, R is the first radius, a is the second radius, and k is the preset number.

[0038] In the embodiment of step 201, in order to ensure uniform distribution and reasonable filling rate of fuel particles in the fuel column, the volume of each cylindrical area is first calculated based on the preset number, the outer diameter of each cylindrical area, the first radius of the dispersed fuel and the second radius of the fuel particles, and the number of all fuel particles in each cylindrical area is determined based on each volume. The purpose of this is to ensure that the fuel particles are distributed in each cylindrical area in a linear relationship, so as to achieve a uniform filling rate in the entire fuel column, so that the temperature distribution calculated by the simulation is more in line with the actual situation.

[0039] Specifically, the volume of each cylindrical area is first calculated. Based on the outer diameter of the cylindrical area and the outer diameter of the cylindrical area of ​​the previous layer, the volume of each cylindrical area is obtained by the following formula: ; Among them, Vi is the volume of the i-th cylindrical area, R is the first radius of the fuel column, a is the second radius of the fuel particle, k is the preset number of partitions, and i is the partition number. This volume calculation method ensures that the volume and position parameters of each partition are consistent, reflecting the trend of the partition radius increasing with the distance from the center of the fuel column, and ensuring the spatial uniformity of the partition from the inside to the outside.

[0040] Next, the number of fuel particles in each partition is calculated based on the volume of the partition, where the number of all fuel particles in the first cylindrical zone (i.e., the central cylindrical zone) is 1. Through a linear relationship, the number of particles ni in each cylindrical zone is determined to be proportional to its volume, and is a constant term, so the number of all fuel particles in each cylindrical area can be expressed by the following formula: ; Where i is the partition number, and ni is the number of particles in the i-th partition. This calculation method ensures that the number of particles in each cylindrical area corresponds to its spatial volume, so that the particle filling rate of each partition is consistent, and the fuel particles are evenly distributed in the fuel column. The advantage of this distribution method is that the particle density of each partition is relatively uniform, whether it is the cylindrical area near the center or the outer layer, thus avoiding the phenomenon of local aggregation or sparseness.

[0041] Step 202: Calculate the central cylindrical coordinates of each cylindrical area based on the preset number, each outer diameter, the first radius and the second radius.

[0042] In a possible implementation, in step 202, the central cylindrical coordinates of each cylindrical area are calculated by the following formula: ; in, is the central cylindrical coordinate of the i-th cylindrical area, is the outer diameter of the i-th cylindrical area, R is the first radius, a is the second radius, and k is the preset number.

[0043] In the embodiment of step 202, in order to ensure the uniform distribution and position accuracy of the fuel particles in the fuel column, the central cylindrical coordinates of each cylindrical area are calculated based on the outer diameter of each cylindrical area, the first radius of the dispersed fuel and the second radius of the fuel particles. The purpose of this is to accurately locate the central cylindrical surface of each cylindrical area so that the fuel particles are evenly distributed on the cylindrical surface in each partition, thereby forming a spatial distribution structure that conforms to the actual situation in the entire fuel column, so as to ensure the accuracy of the temperature distribution calculation.

[0044] Specifically, the central cylindrical coordinates of each cylindrical area are calculated by the following formula: ; in, is the central cylindrical coordinate of the i-th cylindrical area, is the outer diameter of the i-th cylindrical zone, R is the first radius, a is the second radius, and k is the preset number. The calculation formula determines the position of the central cylinder through the outer diameter of each cylindrical zone and the partition thickness, ensuring that each partition gradually expands outward from the center of the fuel column, so that the spacing between the central cylinders of each partition is consistent.

[0045] After calculating the central cylindrical coordinates of each cylindrical area, the specific position of the fuel particles can be further accurately located in each cylindrical area. This method allows the fuel particles in each cylindrical area to be evenly distributed on its central cylindrical surface, avoiding the aggregation or sparseness of particles in the partition, thus forming an overall uniform filling structure.

[0046] Step 203: Based on each quantity and each volume, all the fuel particles in each cylindrical area are evenly distributed on the central cylinder of each cylindrical area, and based on each central cylinder coordinate, the spatial position coordinates of all the fuel particles in each cylindrical area are generated.

[0047] In the embodiment of step 203, in order to ensure that the spatial position of the fuel particles in each cylindrical area is accurately and evenly distributed on the respective central cylindrical surfaces, the particles are evenly arranged on the central cylindrical surface based on the number and volume of the fuel particles in each cylindrical area, and the specific spatial position coordinates of each fuel particle are generated based on the calculated central cylindrical surface coordinates. The purpose of this is to accurately locate the position of each fuel particle so that the fuel particles in each partition are evenly distributed, thereby establishing a geometric model that conforms to the actual distribution characteristics for the entire fuel column, and ensuring the accuracy of subsequent temperature field calculations.

[0048] Specifically, the number and volume of fuel particles in each cylindrical area calculated in step 201 are first used to evenly distribute the particles on the central cylinder of each partition. By setting the intervals reasonably, the particles in each cylindrical area are arranged equidistantly on the central cylinder of the partition, so that the particles maintain a uniform packing density in the partition. The center position of each particle is determined based on the central cylinder coordinates calculated in step 202 to ensure that all particles are located at the correct position of their respective partitions.

[0049] On this basis, the spatial position coordinates of each fuel particle are generated according to the geometric characteristics of each cylindrical area and the central cylindrical coordinates. These position coordinates accurately describe the particle layout of each cylindrical area in the fuel column, ensuring the uniformity of particle distribution and filling density in the entire fuel column. This design avoids the dense or sparse distribution of particles in the fuel column and ensures that the particles in each partition present a consistent spatial arrangement structure.

[0050] Step 102: Import all spatial position coordinates into finite element simulation software to establish a geometric model containing fuel particles.

[0051] In the embodiment of step 102, in order to accurately reproduce the spatial distribution characteristics of the fuel particles in the fuel column and ensure that the spatial position of each fuel particle conforms to the actual situation, the spatial position coordinates of all the fuel particles generated in step 101 are imported into the finite element simulation software COMSOL Multiphysics 5.5 to construct a geometric model containing the fuel particles, thereby laying a foundation for the subsequent accurate calculation of the temperature distribution. The purpose of doing so is to use an accurate geometric model to reflect the actual distribution of the fuel particles, avoid the distribution error caused by the simplified processing, and ensure the accuracy and reliability of the temperature field simulation.

[0052] Specifically, MATLAB is first used to generate the uniform coordinate position of the fuel particles in each cylindrical area, and then the spatial position data of these particles are imported into COMSOL. The specific operation includes writing code in MATLAB to generate and store the position coordinates of all fuel particles, and further developing the code to integrate this position information with COMSOL Multiphysics5.5. Load these coordinate data in COMSOL to establish a fuel geometry model that conforms to the actual physical distribution, ensuring that the distribution structure of each cylindrical area and the fuel particles therein is consistent with the actual design. This geometric model reflects the actual layout of TRISO-coated particles in the graphite matrix in the fuel column, thereby ensuring the geometric accuracy of subsequent simulation calculations.

[0053] Step 103: Set the calculation conditions of the geometric model.

[0054] In a possible implementation, the calculation conditions include thermal conductivity of various materials, internal heat source parameters, and boundary conditions.

[0055] In the embodiment of step 103, in order to make the geometric model truly reflect the heat conduction characteristics in the fuel column in the simulation calculation, it is necessary to set the calculation conditions of the geometric model, including the thermal conductivity of each material, the internal heat source parameters and the boundary conditions. The purpose of doing so is to give the model real physical properties to ensure that the distribution of the temperature field in the simulation process conforms to the actual situation of the fuel column, thereby improving the accuracy and credibility of the calculation.

[0056] Specifically, after the geometric model is established, the calculation conditions are set. First, for different materials (such as the layers of TRISO coated particles and the graphite matrix), the corresponding thermal conductivity is set in COMSOL Multiphysics 5.5. The interior of the TRISO particle is composed of multiple layers of different materials, and the thermal conductivity of each layer is different. Therefore, in order to accurately simulate the thermal conductivity characteristics of these materials, it is necessary to set the thermal conductivity of the uranium dioxide fuel core, the loose pyrolytic carbon layer, the inner dense layer, the silicon carbide layer, and the outer dense pyrolytic carbon layer in sequence. This multi-layer thermal conductivity setting ensures that each fuel particle exhibits real thermal conductivity characteristics in the simulation, avoiding the simulation error caused by approximating the fuel column as a homogeneous body.

[0057] Secondly, set the internal heat source parameters. TRISO coated particles are distributed internal heat sources, and their internal heat source parameters have a direct impact on the temperature distribution. By setting the internal heat source parameters of the fuel particles in COMSOL, the self-heating effect of the fuel under normal operating conditions can be simulated, so that the temperature distribution is closer to the actual working conditions. In addition, the internal heat source setting can also reflect the thermal response of the fuel column under different load conditions, making the simulation process more adaptable.

[0058] Finally, set the boundary conditions. The boundary conditions include the heat flow boundary conditions outside the fuel column, the heat exchange parameters with the external environment, etc. By setting these boundary conditions, the simulation model of the fuel column can be connected with the external thermal environment, so that the temperature field calculation takes into account both the internal heat conduction and the thermal balance between the fuel column and the external environment. This can not only simulate the heat diffusion inside the fuel column, but also show its overall thermal behavior with the outside world.

[0059] Step 104: meshing the geometric model, and calculating the fuel temperature distribution based on the meshing and calculation conditions.

[0060] In the embodiment of step 104, in order to accurately simulate the heat conduction characteristics and temperature field distribution in the fuel column, the geometric model is finely meshed, and the fuel temperature distribution is numerically calculated based on the mesh and the set calculation conditions. Figure 4 , Figure 4 It is a schematic diagram of the fuel finite element mesh provided by the present invention. Figure 4 The mesh division shown demonstrates the detailed modeling of the fuel column and the fuel particles therein. This mesh structure can not only fully reflect the distribution characteristics of the particles, but also capture the changes in temperature gradients at the interfaces of different materials, thus providing a basis for high-precision temperature field simulation.

[0061] Specifically, in COMSOL Multiphysics 5.5, the entire fuel column is first meshed according to its geometric characteristics and material properties. Since TRISO coated particles are composed of multiple layers of material and the thermal conductivity of each layer varies greatly, meshing is performed in the particle interface area. Figure 4 The enlarged image on the right clearly shows this detailed grid structure, in which each layer of coating material of the fuel particle is divided into independent units, so as to ensure that the heat conduction changes between different materials can be accurately captured. At the same time, the interface area between the particle and the matrix graphite is also finely gridded to ensure that the transfer of heat flow at the interface between the two materials can be truly reflected.

[0062] After the meshing is completed, the temperature field is numerically calculated based on the set calculation conditions (including material thermal conductivity, internal heat source parameters and boundary conditions). Since TRISO particles are distributed in the fuel column as internal heat sources, the influence of the self-heating of each particle on the overall temperature field can be reflected in the numerical calculation process, and the simulation results can reveal the distribution of hot spots in the fuel column and the changing trend of the temperature gradient. Through this refined meshing and comprehensive calculation condition setting, the simulation model can accurately reflect the actual thermal behavior of the fuel column and provide high-resolution temperature field data for subsequent temperature analysis and verification.

[0063] This numerical calculation of the temperature field based on fine grid division can effectively ensure the accuracy of the calculation results, avoid temperature gradient errors caused by coarse grids, make the temperature distribution simulation of the fuel column closer to the actual situation, and provide high-quality reference data for the thermal design and safety analysis of high-temperature gas-cooled reactors.

[0064] Step 105: After the fuel temperature distribution passes the grid independence verification, the maximum fuel temperature and the average temperature of all cylinder areas are extracted from the fuel temperature distribution.

[0065] In the embodiment of step 105, in order to verify the accuracy of the calculated fuel temperature distribution and extract the key temperature parameters in the fuel column, the fuel temperature distribution is verified to be grid-independent to ensure that the calculation results are independent of the level of grid division. Only after the verification is passed can the maximum temperature of the fuel column and the average temperature of each cylindrical area be accurately extracted from the temperature distribution. The purpose of this is to ensure the stability and reliability of the numerical results of the temperature field and avoid deviations in the calculation results due to improper grid division, so as to provide accurate temperature data for the thermal design and safety analysis of the high-temperature gas-cooled reactor.

[0066] Specifically, firstly, based on the temperature distribution result in step 104, the grid independence verification is performed, that is, the temperature distribution is recalculated under different grid densities, and the difference in the results of each calculation is compared. If the temperature distribution result does not change significantly under a finer grid division, it means that the temperature field distribution is not affected by the grid and the verification is passed; if there is a significant change, the grid needs to be further refined and recalculated until the result is stable. This verification process ensures the stability of the numerical calculation and eliminates the interference of the grid thickness on the temperature distribution.

[0067] After the grid independence verification is passed, the key temperature parameters in the fuel column are extracted from the stabilized temperature distribution data, including the maximum temperature of the fuel column and the average temperature of each cylindrical area. The maximum temperature can intuitively reflect the hot spot area in the fuel column, which helps to evaluate the tolerance of the fuel coating material under extreme conditions and determine whether there are potential safety risks; while the average temperature of each cylindrical area provides the overall temperature level of each area, which helps to comprehensively analyze the thermal field distribution of the fuel column and guide thermal design and material selection.

[0068] In one possible implementation, refer to Figure 5 , Figure 5 FIG. 3 is a flow chart of the thermal conductivity analysis method provided by the present invention. Figure 5 As shown, the method further includes step 301: Step 301: After the fuel temperature distribution fails to pass the grid independence verification, the grid density is adjusted, and the steps of meshing the geometric model and calculating the fuel temperature distribution based on the meshing and calculation conditions are re-executed until the fuel temperature distribution passes the grid independence verification.

[0069] In the embodiment of step 301, in order to ensure the accuracy of the fuel temperature distribution calculation results, grid independence verification is required to determine whether the calculation results are sensitive to changes in grid density. If the temperature distribution fails the grid independence verification, the grid density needs to be further adjusted and recalculated until the verification passes. The purpose of doing so is to gradually refine the grid and eliminate the temperature distribution deviation caused by improper grid division, so as to ensure the stability and reliability of the numerical calculation and provide accurate temperature data support for subsequent temperature analysis.

[0070] Specifically, based on the calculation results of the previous round of temperature distribution, the calculation results under different grid densities are compared and analyzed to observe the sensitivity of the temperature field to the change of the grid. If the temperature field calculation results do not change significantly under a higher density grid division, it means that the current grid division has met the accuracy requirements and the verification has passed; but if the calculation results change significantly, it means that the grid density is still not enough to accurately describe the temperature distribution of the fuel particles, and the grid density needs to be further adjusted. To this end, the original grid is encrypted, especially in areas with large temperature gradients (such as the fuel particle interface and TRISO coating) to capture the subtle features of local temperature changes.

[0071] After the mesh density is adjusted, the numerical calculation of the temperature distribution is re-executed and the mesh independence verification is performed again. The repeated adjustment and verification process ensures the stability of the final calculation results and eliminates the influence of mesh division on the temperature field distribution. This process continues until the temperature distribution results are no longer sensitive to the mesh density and the temperature distribution under each mesh density tends to be consistent, passing the mesh independence verification.

[0072] Reference Figure 6 , Figure 6 It is a structural schematic diagram of the thermal conductivity analysis system provided by the present invention, the system comprises: a coordinate establishment module, which is used to divide the dispersed fuel into a preset number of cylindrical areas and establish the spatial position coordinates of all fuel particles in each cylindrical area; A geometric model building module is used to import all spatial position coordinates into the finite element simulation software to build a geometric model containing fuel particles; A processing module, used to set the calculation conditions of the geometric model; The processing module is also used to mesh the geometric model and calculate the fuel temperature distribution based on the meshing and calculation conditions; The processing module is also used to extract the maximum fuel temperature and the average temperature of all cylinder areas from the fuel temperature distribution after the fuel temperature distribution passes the grid independence verification.

[0073] In a possible implementation, the coordinate establishment module is further used for: Based on the preset number, the first radius of the dispersed fuel and the second radius of the fuel particles, the outer diameter of each cylindrical area is calculated; the outer diameter of each cylindrical area is calculated by the following formula: ; Among them, k is the preset number, is the outer diameter of the i-th cylindrical zone, R is the first radius, and a is the second radius; The dispersed fuel is divided based on each outer diameter to obtain a preset number of cylindrical zones.

[0074] In a possible implementation, the coordinate establishment module is further used for: Calculating the volume of each cylindrical region based on the preset number, each outer diameter, the first radius, and the second radius, and determining the number of all fuel particles in each cylindrical region based on each volume, wherein each number is linearly related to each volume; Calculating the central cylindrical coordinates of each cylindrical region based on the preset number, each outer diameter, the first radius, and the second radius; Based on each quantity and each volume, all the fuel particles in each cylindrical area are evenly distributed on the central cylinder of each cylindrical area, and based on each central cylinder coordinate, the spatial position coordinates of all the fuel particles in each cylindrical area are generated.

[0075] In one possible implementation, the processing module is further used to adjust the grid density and re-execute the steps of meshing the geometric model and calculating the fuel temperature distribution based on the meshing and calculation conditions after the fuel temperature distribution fails to pass the grid independence verification, until the fuel temperature distribution passes the grid independence verification.

[0076] It should be noted that the thermal conductivity analysis system provided by the present invention can execute the thermal conductivity analysis method of any of the above embodiments during specific operation, which will not be elaborated in this embodiment.

[0077] Figure 7 is a schematic diagram of the structure of the electronic device provided by the present invention, such as Figure 7As shown, the electronic device may include: a processor 710 (processor), a communication interface 720 (CommunicationsInterface), a memory 730 (memory) and a communication bus 740, wherein the processor 710, the communication interface 720, and the memory 730 communicate with each other through the communication bus 740. The processor 710 may call the logic instructions in the memory 730 to execute the thermal conductivity analysis method, which includes: dividing the dispersed fuel into a preset number of cylindrical areas, and establishing the spatial position coordinates of all fuel particles in each cylindrical area; importing all spatial position coordinates into finite element simulation software to establish a geometric model containing fuel particles; setting the calculation conditions of the geometric model; meshing the geometric model, and calculating the fuel temperature distribution based on the meshing and calculation conditions; after the fuel temperature distribution passes the mesh independence verification, extracting the maximum fuel temperature and the average temperature of all cylindrical areas from the fuel temperature distribution.

[0078] In addition, the logic instructions in the above-mentioned memory 730 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0079] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by the computer, the computer can execute the thermal conductivity analysis method provided by the above-mentioned embodiments, and the method includes: dividing the dispersed fuel into a preset number of cylindrical areas, and establishing the spatial position coordinates of all fuel particles in each cylindrical area; importing all spatial position coordinates into finite element simulation software to establish a geometric model containing fuel particles; setting calculation conditions for the geometric model; meshing the geometric model, and calculating the fuel temperature distribution based on the meshing and calculation conditions; after the fuel temperature distribution passes the mesh independence verification, extracting the maximum fuel temperature and the average temperature of all cylindrical areas from the fuel temperature distribution.

[0080] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the processor 710 executes the thermal conductivity analysis method provided in the above-mentioned embodiments, the method comprising: dividing the dispersed fuel into a preset number of cylindrical areas, and establishing the spatial position coordinates of all fuel particles in each cylindrical area; importing all the spatial position coordinates into finite element simulation software to establish a geometric model containing fuel particles; setting calculation conditions for the geometric model; meshing the geometric model, and calculating the fuel temperature distribution based on the meshing and calculation conditions; after the fuel temperature distribution passes the grid independence verification, extracting the maximum fuel temperature and the average temperature of all cylindrical areas from the fuel temperature distribution.

[0081] The system embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, i.e., they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0082] Through the description of the above implementation modes, those skilled in the art can clearly understand that each implementation mode can be implemented by means of software plus a necessary general hardware platform, or of course by hardware. Based on such an understanding, the above technical solution can essentially or in other words be embodied in the form of a software product that contributes to the prior art. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of each embodiment or some parts of the embodiment.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A thermal conductivity analysis method, characterized in that: include: Dividing the dispersed fuel into a preset number of cylindrical areas, and establishing the spatial position coordinates of all fuel particles in each of the cylindrical areas; Importing all the spatial position coordinates into finite element simulation software to establish a geometric model containing fuel particles; Setting calculation conditions of the geometric model; Meshing the geometric model, and calculating fuel temperature distribution based on the meshing and the calculation conditions; After the fuel temperature distribution is verified to be grid independent, the maximum fuel temperature and the average temperature of all cylinder areas are extracted from the fuel temperature distribution.

2. The thermal conductivity analysis method according to claim 1, characterized in that: The step of dividing the dispersed fuel into a preset number of cylindrical areas specifically includes: Based on the preset number, the first radius of the dispersed fuel and the second radius of the fuel particles, the outer diameter of each cylindrical area is calculated; the outer diameter of each cylindrical area is calculated by the following formula: ； Wherein, k is the preset number, is the outer diameter of the i-th cylindrical zone, R is the first radius, and a is the second radius; The dispersed fuel is divided based on each of the outer diameters to obtain a preset number of cylindrical areas.

3. The thermal conductivity analysis method according to claim 2, characterized in that: The step of establishing the spatial position coordinates of all fuel particles in each cylindrical area specifically includes: Calculating the volume of each of the cylindrical regions based on the preset number, each of the outer diameters, the first radius, and the second radius, and determining the number of all fuel particles in each of the cylindrical regions based on each of the volumes, wherein each of the numbers is linearly related to each of the volumes; Calculating the central cylindrical coordinates of each of the cylindrical areas based on the preset number, each of the outer diameters, the first radius, and the second radius; Based on each of the quantities and each of the volumes, all of the fuel particles in each of the cylindrical regions are evenly distributed on the central cylinder of each of the cylindrical regions, and based on each of the central cylinder coordinates, the spatial position coordinates of all of the fuel particles in each of the cylindrical regions are generated.

4. The thermal conductivity analysis method according to claim 3, characterized in that: The number of all fuel particles in the first cylindrical area is 1; the volume of each cylindrical area is calculated based on the preset number, each outer diameter, the first radius and the second radius, and the number of all fuel particles in each cylindrical area is determined based on each volume, specifically including: The volume of each cylindrical area is calculated by the following formula: ； The number of all fuel particles in each cylindrical area is expressed by the following formula: ； in, is the volume of the i-th cylindrical region, is the outer diameter of the i-th cylindrical zone, is the outer diameter of the i-1th cylindrical area, R is the first radius, a is the second radius, and k is the preset number.

5. The thermal conductivity analysis method according to claim 3, characterized in that: The calculating the central cylindrical coordinates of each of the cylindrical areas based on the preset number, each of the outer diameters, the first radius, and the second radius specifically includes: The central cylindrical coordinates of each cylindrical area are calculated by the following formula: ； in, is the central cylindrical coordinate of the i-th cylindrical area, is the outer diameter of the i-th cylindrical area, R is the first radius, a is the second radius, and k is the preset number.

6. The thermal conductivity analysis method according to claim 1, characterized in that: The calculation conditions include thermal conductivity of various materials, internal heat source parameters and boundary conditions.

7. The thermal conductivity analysis method according to claim 1, characterized in that: The method further comprises: After the fuel temperature distribution fails to pass the grid independence verification, the grid density is adjusted, and the steps of meshing the geometric model and calculating the fuel temperature distribution based on the meshing and the calculation conditions are re-executed until the fuel temperature distribution passes the grid independence verification.

8. A thermal conductivity analysis system, characterized in that: include: A coordinate establishment module, used to divide the dispersed fuel into a preset number of cylindrical areas and establish the spatial position coordinates of all fuel particles in each of the cylindrical areas; A geometric model building module, used to import all the spatial position coordinates into finite element simulation software to build a geometric model containing fuel particles; A processing module, used for setting the calculation conditions of the geometric model; The processing module is further used to mesh the geometric model and calculate the fuel temperature distribution based on the mesh and the calculation conditions; The processing module is also used to extract the maximum fuel temperature and the average temperature of all cylinder areas from the fuel temperature distribution after the fuel temperature distribution passes the grid independence verification.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the thermal conductivity analysis method according to any one of claims 1 to 7 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the thermal conductivity analysis method according to any one of claims 1 to 7 is implemented.

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