Boundary condition determination method and system of hot rod and computer readable medium
By constructing a hot rod correlation model and combining the best estimation and uncertainty analysis, sensitivity analysis and multi-objective optimization algorithms are used to iteratively update the boundary conditions, which solves the problem that it is difficult to obtain accurate and reliable hot rod boundary conditions in the prior art. Improve the reliability and economical operation of nuclear power plants.
Patent Information
- Application Number
- CN202411535121.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-31
- Publication Date
- 2025-02-11
AI Technical Summary
The prior art is difficult to obtain accurate and reliable thermal rod boundary conditions, which affects the safety and economics of nuclear power plants.
By obtaining the nuclear power plant system and its influencing parameters, a hot rod-related model is constructed, combining the best estimation and uncertainty analysis, and the boundary conditions iteratively updated using sensitivity analysis and multi-objective optimization algorithm.
A more accurate evaluation of the performance of the hot rod is achieved, which improves the reliability and economical operation of the nuclear power plant and reduces the calculation volume and cost.
Smart Images
Figure CN119416509A_ABST
Abstract
Description
Technical Field
[0001] The present invention mainly relates to the technical field of thermal hydraulic safety analysis of nuclear power plants, and in particular to a method and system for determining boundary conditions of a thermal rod and a computer-readable medium. Background Art
[0002] As a high-energy-density energy facility, the safety of nuclear power plants is of vital importance. Any accidents may bring serious environmental and health impacts. One of the key links to ensure the stable operation of nuclear power plants and prevent potential risks is the thermal-hydraulic analysis of nuclear power plants. The analysis process involves a variety of complex physical phenomena, including heat transfer, fluid flow heat exchange, and phase change. The complexity of these phenomena requires that the constructed analysis model must be able to accurately simulate the actual operating conditions. In order to obtain accurate thermal-hydraulic analysis results, more accurate hot rod boundary conditions are required.
[0003] In the process of determining the boundary conditions of hot rods, traditional deterministic safety analysis methods are usually based on conservative assumptions and simplified models, which may lead to an overestimation of potential risks. In contrast, the Best Estimate method (BE) attempts to use models and parameters that are closer to reality to provide more accurate prediction results. However, given the diversity and complexity of nuclear power plant operating conditions, as well as the inherent uncertainty of the model and input data themselves, it is necessary to introduce uncertainty analysis, which helps to evaluate the credibility of the prediction results and provide decision makers with more comprehensive information. Official agencies have begun to recommend the use of the Best Estimate Plus Uncertainty (BEPU) method as the development trend of nuclear power plant safety analysis. This method combines best estimates and uncertainty analysis to provide a more comprehensive and reliable safety assessment.
[0004] At present, when determining the boundary conditions of hot rods in nuclear power plants, it is still difficult to obtain accurate hot rod boundary conditions by only using BE or BEPU methods. Summary of the invention
[0005] The technical problem to be solved by the present application is to provide a method, system and computer-readable medium for determining the boundary conditions of a heat rod, which can obtain accurate and reliable boundary conditions of the heat rod, can truly reflect the performance of the heat rod, and can improve the economy of the nuclear power plant.
[0006] The technical solution adopted by the present application to solve the above-mentioned technical problems is a method for determining the boundary conditions of a hot rod, comprising: step S1: obtaining a nuclear power plant system related to the hot rod calculation; obtaining a first influencing parameter affecting the performance of the hot rod; obtaining an optimal estimation system corresponding to the nuclear power plant system; step S2: identifying the second influencing parameter of the hot rod in the nuclear power plant system, and constructing a relevant model of the hot rod according to the optimal estimation system and the second influencing parameter; step S3: setting the initial value of the boundary condition, simulating the relevant model of the hot rod according to the sensitivity analysis method and the initial value of the boundary condition, and obtaining the hot rod performance impact result; step S4: performing a sensitivity analysis calculation on the first influencing parameter according to the sensitivity analysis method and the optimal estimation system, and obtaining a first analysis result; quantifying the first impact result of the first influencing parameter on the boundary condition according to a statistical method; step S5: iteratively updating the boundary condition according to the first analysis result and the first impact result, and obtaining an updated boundary condition value.
[0007] In one embodiment of the present application, after step S5, it also includes: step S6: simulating various operating conditions of the nuclear power plant, testing the hot rod according to the various operating conditions and updated boundary condition values, and obtaining hot rod test data; step S7: updating the program model of the optimal estimation system according to the hot rod test data, and switching to execute step S2.
[0008] In one embodiment of the present application, in step S6, after the step of obtaining the hot rod test data, it also includes: calculating the error between the hot rod test data and the preset target data; judging whether the error is less than or equal to a preset threshold value, if it is judged as yes, then ending the execution of the boundary condition determination method; if it is judged as no, then switching to executing step S7.
[0009] In one embodiment of the present application, the first influencing parameter includes: one or any combination of flow operating parameters, flow velocity operating parameters, ambient temperature parameters, ambient pressure parameters, and material properties; the second influencing parameter includes: one or any combination of heat rod design parameters, heat rod operating environment, and expected performance of the heat rod; the relevant model of the heat rod includes: one or any combination of heat conduction model, convection heat transfer model, and heat rod dynamic response model.
[0010] In one embodiment of the present application, the optimal estimation system is configured to: simulate the behavior of a nuclear power plant under transient or accident conditions; and output physical phenomena and / or the impact of physical phenomena of the nuclear power plant.
[0011] In one embodiment of the present application, the sensitivity analysis method is a moment-independent global sensitivity analysis method, which can optimize the calculation process based on Gaussian quadrature and high-dimensional model representation.
[0012] In one embodiment of the present application, the statistical method is a Monte Carlo simulation method.
[0013] In one embodiment of the present application, in step S5, a multi-objective optimization algorithm is used to iteratively update the boundary conditions; the multi-objective optimization algorithm includes a genetic algorithm or a particle swarm optimization algorithm.
[0014] In order to solve the above technical problems, the present application also proposes a boundary condition determination system for a hot rod, comprising: a memory for storing instructions executable by a processor; a processor for executing instructions to implement the above boundary condition determination method for a hot rod.
[0015] In order to solve the above technical problems, the present application also proposes a computer-readable medium storing computer program codes, and the computer program codes implement the above boundary condition determination method of the hot rod when executed by a processor.
[0016] The technical solution of the present application can more comprehensively consider the operation of the hot rod in the nuclear power plant system by acquiring the nuclear power plant system and its influencing parameters related to the hot rod calculation and constructing a relevant model of the hot rod, which helps to more accurately evaluate the performance of the hot rod; by performing sensitivity analysis calculation and statistical quantification on the first influencing parameter, the reasonable value of the boundary condition can be determined more accurately, so as to better iterate and update the boundary conditions, and gradually approach the optimal boundary condition value, thereby improving the reliability of the hot rod design and operation.
[0017] This application is equivalent to the method used to determine the boundary conditions of the hot rod in the best estimate system program. In practical applications, the boundary conditions of the hot rod can be determined by combining the Phenomena Identification and Ranking Table (PIRT) and sensitivity analysis. This application not only takes into account the uncertainty of the input parameters, but also optimizes the prediction ability of the model through an iterative process, and innovates the safety analysis method of nuclear power plants. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below with reference to the accompanying drawings, wherein:
[0019] Figure 1 is an exemplary flow chart of a method for determining boundary conditions of a hot rod according to an embodiment of the present application;
[0020] Figure 2 is an exemplary flow chart of a method for determining boundary conditions of a hot rod according to another embodiment of the present application;
[0021] Figure 3 It is a system block diagram of a boundary condition determination system of a hot rod according to an embodiment of the present application. DETAILED DESCRIPTION
[0022] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below with reference to the accompanying drawings.
[0023] In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application may also be implemented in other ways different from those described herein, and therefore the present application is not limited to the specific embodiments disclosed below.
[0024] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.
[0025] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may be added to these processes, or one or more operations may be removed from these processes.
[0026] The present application proposes a method for determining boundary conditions of a heat rod, which can be applied to thermal hydraulic safety analysis scenarios in pressurized water reactor nuclear power plants, etc.
[0027] Figure 1 is an exemplary flow chart of a method for determining boundary conditions of a hot rod according to an embodiment of the present application, with reference to Figure 1 As shown, the method for determining the boundary conditions of the hot rod of this embodiment includes the following steps:
[0028] Step S1: obtain a nuclear power plant system related to heat rod calculation; obtain a first influencing parameter affecting the performance of the heat rod; and obtain an optimal estimation system corresponding to the nuclear power plant system.
[0029] Step S2: Identify the second influencing parameter of the heat rod in the nuclear power plant system, and construct a related model of the heat rod according to the best estimation system and the second influencing parameter.
[0030] Step S3: setting the initial values of the boundary conditions, simulating the relevant models of the hot rod according to the sensitivity analysis method and the initial values of the boundary conditions, and obtaining the results of the impact on the performance of the hot rod.
[0031] Step S4: Perform sensitivity analysis calculation on the first influencing parameter according to the sensitivity analysis method and the optimal estimation system to obtain a first analysis result; and quantify the first influence result of the first influencing parameter on the boundary condition according to a statistical method.
[0032] Step S5: Iteratively update the boundary condition according to the first analysis result and the first impact result to obtain an updated boundary condition value.
[0033] Exemplarily, the nuclear power plant system mentioned in the present application may be a physical system in a nuclear power plant working scenario, and the best estimation system is a software system. Figure 2 is an exemplary flow chart of a method for determining boundary conditions of a hot rod according to another embodiment of the present invention. Figure 2 The above steps S1 to S5 are described in detail:
[0034] In step S1, a nuclear power plant system related to the heat rod calculation is obtained; a first influencing parameter affecting the heat rod performance is obtained; and an optimal estimation system corresponding to the nuclear power plant system is obtained. Exemplarily, step S1 can be subdivided into step S1a, step S1b, and step S1c.
[0035] Step S1a: Obtain the nuclear power plant system related to the heat rod calculation. This step S1a corresponds to Figure 2 Step S210: Determine the nuclear power plant system. Exemplarily, although the reactor systems of most nuclear power plants are similar, there are fewer systems related to the calculation of the heat rod, and the corresponding piping systems and individual components of different nuclear power plants are quite different, and the uncertainty depends largely on the phenomena and components identified according to PIRT, so selecting the corresponding nuclear power plant system is important for the subsequent analysis steps. The nuclear power plant system can be the reactor cooling system, heat exchange system, control system, etc. where the heat rod is located.
[0036] Step S1b: Obtain the first influencing parameter affecting the performance of the hot rod. This step S1b corresponds to Figure 2 Step S220: Parameter identification and classification. In some embodiments, the first influencing parameter includes: flow rate operating parameter, flow velocity operating parameter, ambient temperature parameter, ambient pressure parameter, material property, or any combination thereof.
[0037] Exemplarily, all parameters that may affect the performance of the hot rod can be identified through system analysis, including operating parameters (such as flow and flow rate), environmental parameters (such as temperature and pressure), and material properties. In practical applications, the identified parameters can be systematically classified, and their normal operating ranges and limit conditions can be defined. Starting from the nuclear power plant system, the present application can identify important systems and related phenomena that may affect the boundaries of the hot rod, and identify and determine all parameters that may affect the performance of the hot rod through system analysis, thereby facilitating the determination of the normal operating range and limit conditions.
[0038] Step S1c: Obtain the best estimation system corresponding to the nuclear power plant system. This step S1c corresponds to Figure 2Step S230: determine the best estimation system program. In some embodiments, the best estimation system is configured to: simulate the behavior of the nuclear power plant under transient or accident conditions; output the physical phenomena of the nuclear power plant and / or the impact of the physical phenomena. Exemplarily, after determining the nuclear power plant system, the corresponding best estimation system program is selected, which must ensure that it can simulate the behavior of the nuclear power plant under transient or accident conditions, can truly reflect the physical phenomena of the nuclear power plant, and take into account all important phenomena or encompass the impact of all important phenomena.
[0039] In step S2, a second influencing parameter of the hot rod in the nuclear power plant system is identified, and a related model of the hot rod is constructed according to the best estimation system and the second influencing parameter. This step S2 corresponds to Figure 2 Step S240: System analysis and modeling. In some embodiments, the second influencing parameter includes: one or any combination of heat rod design parameters, heat rod operating environment, and expected performance of the heat rod. The relevant model of the heat rod includes: one or any combination of heat conduction model, convection heat transfer model, and heat rod dynamic response model.
[0040] For example, a comprehensive analysis can be conducted on the determined nuclear power plant system to identify the role and influence of the hot rod in the nuclear power plant system, including its design parameters (such as material, size, working fluid, power, etc.), operating environment (such as temperature, radiation, fluid, etc.) and expected performance, etc. After the role and influence of the hot rod are identified, the best estimation system program determined in the above steps is used to establish relevant models of the hot rod (such as heat conduction model, convection heat transfer model, hot rod dynamic response model, etc.) to simulate the behavior of the hot rod under different working conditions.
[0041] For example, in practical applications, the development of a sensitivity analysis method can be performed separately, so that the boundary conditions of the hot rod can be determined in combination with the sensitivity analysis method in the future. The development or selection of a sensitivity analysis method suitable for a complex nuclear reactor system requires ensuring that the method can handle nonlinear and non-monotonic system responses. In some embodiments, the sensitivity analysis method is a moment-independent global sensitivity analysis method, which can optimize the calculation process according to Gaussian quadrature and high-dimensional model representation techniques, etc., which can reduce the amount of calculation and improve the accuracy of the analysis, and can also optimize the calculation method to improve the calculation efficiency.
[0042] In step S3, the initial values of the boundary conditions are set, and the relevant models of the hot rod are simulated according to the sensitivity analysis method and the initial values of the boundary conditions to obtain the results of the hot rod performance impact. This step S3 corresponds to Figure 2Step S250: Preliminary determination of boundary conditions. For example, preliminary values of boundary conditions can be set according to the design requirements of the heat rod and the operation specifications of the nuclear power plant, and the sensitivity analysis method developed or selected is used to simulate with the corresponding heat rod system model to analyze the preliminary impact of these boundary conditions on the performance of the heat rod.
[0043] In step S4, a sensitivity analysis calculation is performed on the first influencing parameter according to the sensitivity analysis method and the best estimation system to obtain a first analysis result; and a first influence result of the first influencing parameter on the boundary condition is quantified according to a statistical method. This step S4 corresponds to Figure 2 Step S260: Sensitivity analysis and uncertainty quantification and analysis. Exemplarily, the present application uses a sensitivity analysis method and a best estimate system program to perform sensitivity analysis calculations. The present application uses statistical methods, such as Monte Carlo simulation methods, to quantify the uncertainty of the hot rod input parameters and their impact on the boundary conditions. In practical applications, the predicted model confidence interval can be evaluated to ensure that the boundary conditions are determined with sufficient confidence.
[0044] Exemplarily, the present application uses the best estimation system program for system analysis and modeling, which can simulate the behavior of the hot rod under different working conditions. In the sensitivity analysis stage, a sensitivity analysis method suitable for a complex nuclear reactor system can be developed or selected, and after sensitivity calculation is performed using a suitable sensitivity analysis method, the calculation results used in subsequent steps can be obtained.
[0045] In step S5, the boundary condition is iteratively updated according to the first analysis result and the first impact result to obtain an updated boundary condition value. This step S5 corresponds to Figure 2 Step S270 in: iterative optimization and adjustment. In some embodiments, in step S5, a multi-objective optimization algorithm is used to iteratively update the boundary conditions. The multi-objective optimization algorithm includes a genetic algorithm or a particle swarm optimization algorithm. Exemplarily, the present application combines the results of sensitivity analysis and uncertainty analysis, optimizes the boundary conditions through an iterative process, and can find boundary conditions that can ensure safety under different working conditions.
[0046] In some embodiments, after step S5, the method further includes:
[0047] Step S6: Simulate various operating conditions of the nuclear power plant, test the hot rod according to the various operating conditions and the updated boundary condition values, and obtain hot rod test data. This step S6 corresponds to Figure 2 Step S280 in the process: Experimental design and verification. For example, a series of experiments can be designed to simulate the operating conditions of a nuclear power plant, including different pressure, temperature, flow conditions, etc. The performance of the hot rod is tested through the experiments, and data is collected to verify the accuracy of the program and the validity of the boundary conditions.
[0048] Step S7: Update the program model of the optimal estimation system according to the hot rod test data, and then proceed to step S2. Step S7 corresponds to Figure 2 Step S290 in: Program improvement. Exemplarily, the program model of the selected best estimation system can be improved using the test data obtained in the above steps to ensure that the best estimation system program can more accurately simulate the behavior of the hot rod under transient or accident conditions.
[0049] In some embodiments, in step S6, after the step of obtaining the hot rod test data, the step further includes:
[0050] Step S61: Calculate the error between the hot rod test data and the preset target data.
[0051] Step S62: Determine whether the error is less than or equal to a preset threshold value. If it is, then end the execution of the boundary condition determination method; if it is not, then go to step S7. For example, if the best estimation system program model can simulate the test results more accurately, a more accurate hot rod boundary condition can be obtained, and the above steps can be no longer repeated.
[0052] For example, in practical applications, case studies and applications can be conducted. For example, multiple power plant cases are selected, and the boundary conditions are determined using the methods and improved procedures described above. Case results are studied and analyzed to evaluate the effectiveness of the methods and identify areas that need further improvement. Knowledge management and continuous improvement can also be conducted, such as establishing a knowledge base to collect data, experience, and lessons learned in the process of boundary condition determination. Knowledge management tools, such as databases and expert systems, are used to promote knowledge sharing and application.
[0053] This application can produce the following beneficial effects:
[0054] 1. This application uses the best estimate plus uncertainty (BEPU) method for analysis, which can more accurately predict the performance of the heat rod in actual operation, thereby enhancing the reliability of the entire system operation. By removing unnecessary conservatism, the heat rod design can be more economical.
[0055] 2. This application reduces the amount of calculation and lowers the computing cost by adopting an efficient global sensitivity analysis method.
[0056] 3. The iterative optimization process proposed in this application allows for continuous improvement of boundary conditions to adapt to new data and empirical feedback, ensuring the continuous adaptability and improvement of the method.
[0057] 4. This application verifies the importance of the model and boundary conditions through experiments, ensuring the practicality and effectiveness of the method.
[0058] 5. This application ensures that the method can be continuously updated and improved with technological progress and industry changes through knowledge management and continuous improvement mechanisms.
[0059] The present application also includes a boundary condition determination system for a hot rod, comprising a memory and a processor, wherein the memory is used to store instructions executable by the processor; and the processor is used to execute the instructions to implement the boundary condition determination method for the hot rod described above.
[0060] Figure 3 is a system block diagram of a boundary condition determination system of a hot rod according to an embodiment of the present application. Figure 3 As shown, the boundary condition determination system 300 of the hot rod may include an internal communication bus 301, a processor 302, a read-only memory (ROM) 303, a random access memory (RAM) 304, and a communication port 305. The boundary condition determination system 300 of the hot rod may also include a hard disk 306. The internal communication bus 301 can realize data communication between the components of the boundary condition determination system 300 of the hot rod. The processor 302 can make judgments and issue prompts. In some embodiments, the processor 302 can be composed of one or more processors. The communication port 305 can realize data communication between the boundary condition determination system 300 of the hot rod and the outside. In some embodiments, the boundary condition determination system 300 of the hot rod can send and receive information and data from the network through the communication port 305. The boundary condition determination system 300 of the hot rod may also include different forms of program storage units and data storage units, such as a hard disk 306, a read-only memory (ROM) 303 and a random access memory (RAM) 304, which can store various data files used for computer processing and / or communication, and possible program instructions executed by the processor 302. The processor executes these instructions to implement the main part of the method. The results processed by the processor are transmitted to the user device through the communication port and displayed on the user interface.
[0061] The above-mentioned method for determining the boundary conditions of the hot rod can be implemented as a computer program, stored in the hard disk 306, and loaded into the processor 302 for execution to implement the method for determining the boundary conditions of the hot rod of the present application.
[0062] The present application also includes a computer-readable medium storing a computer program code, which, when executed by a processor, implements the above-mentioned method for determining the boundary conditions of the hot rod.
[0063] When the boundary condition determination method of the hot rod is implemented as a computer program, it can also be stored in a computer-readable storage medium as a product. For example, a computer-readable storage medium may include, but is not limited to, a magnetic storage device (e.g., a hard disk, a floppy disk, a magnetic strip), an optical disk (e.g., a compact disk (CD), a digital versatile disk (DVD)), a smart card, and a flash memory device (e.g., an electrically erasable programmable read-only memory (EPROM), a card, a stick, a key drive). In addition, the various storage media described herein can represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" can include, but is not limited to, wireless channels and various other media (and / or storage media) that can store, contain and / or carry code and / or instructions and / or data.
[0064] It should be understood that the embodiments described above are only illustrative. The embodiments described herein may be implemented in hardware, software, firmware, middleware, microcode, or any combination thereof. For hardware implementation, the processor may be implemented in one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and / or other electronic units designed to perform the functions described herein, or a combination thereof.
[0065] Some aspects of the present application may be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software may be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". The processor may be one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. In addition, various aspects of the present application may be expressed as computer products located in one or more computer-readable media, which include computer-readable program codes. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, tapes ...), optical disks (e.g., compact disks CDs, digital versatile disks DVDs ...), smart cards, and flash memory devices (e.g., cards, sticks, key drives ...).
[0066] A computer-readable medium may include a propagated data signal containing computer program code, such as in baseband or as part of a carrier wave. The propagated signal may have a variety of manifestations, including electromagnetic, optical, etc., or a suitable combination. A computer-readable medium may be any computer-readable medium other than a computer-readable storage medium, which may be connected to an instruction execution system, device or apparatus to communicate, propagate or transmit a program for use. The program code on the computer-readable medium may be propagated via any suitable medium, including radio, cable, fiber optic cable, radio frequency signal, or similar medium, or any combination of the above mediums.
[0067] The basic concepts have been described above. Obviously, for those skilled in the art, the above application disclosure is only an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.
[0068] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.
[0069] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values is as accurate as possible within the feasible range.
Claims
1. A method for determining boundary conditions of a hot rod, characterized in that: include: Step S1: obtaining a nuclear power plant system related to heat rod calculation; obtaining a first influencing parameter affecting the performance of the heat rod; Obtaining the best estimation system corresponding to the nuclear power plant system; Step S2: identifying a second influencing parameter of the heat rod in the nuclear power plant system, and constructing a relevant model of the heat rod according to the optimal estimation system and the second influencing parameter; Step S3: setting the initial value of the boundary condition, simulating the relevant model of the heat rod according to the sensitivity analysis method and the initial value of the boundary condition, and obtaining the heat rod performance impact result; Step S4: performing sensitivity analysis calculation on the first influencing parameter according to the sensitivity analysis method and the optimal estimation system to obtain a first analysis result; and quantifying a first influence result of the first influencing parameter on the boundary condition according to a statistical method; as well as Step S5: iteratively updating the boundary condition according to the first analysis result and the first impact result to obtain an updated boundary condition value.
2. The boundary condition determination method according to claim 1, characterized in that: After step S5, the method further includes: Step S6: simulating various operating conditions of the nuclear power plant, testing the hot rod according to the various operating conditions and the updated boundary condition values, and obtaining hot rod test data; Step S7: Update the program model of the optimal estimation system according to the hot rod test data, and switch to executing step S2.
3. The boundary condition determination method according to claim 2, characterized in that: In the step S6, after the step of obtaining the hot rod test data, the step further includes: Calculating the error between the hot rod test data and the preset target data; It is determined whether the error is less than or equal to a preset threshold. If it is determined to be yes, the boundary condition determination method is terminated; if it is determined to be no, the step S7 is executed.
4. The boundary condition determination method according to claim 1, characterized in that: The first influencing parameter includes: one or any combination of flow rate operating parameters, flow velocity operating parameters, ambient temperature parameters, ambient pressure parameters, and material properties; The second influencing parameter includes: one or any combination of the hot rod design parameters, the hot rod operating environment, and the hot rod expected performance; The related models of the heat rod include: a heat conduction model, a convection heat transfer model, a heat rod dynamic response model or any combination thereof.
5. The boundary condition determination method according to claim 1, characterized in that: The optimal estimation system is configured to: simulate the behavior of a nuclear power plant under transient or accident conditions; and output physical phenomena of the nuclear power plant and / or the impact of the physical phenomena.
6. The boundary condition determination method according to claim 1, characterized in that: The sensitivity analysis method is a moment-independent global sensitivity analysis method, and the sensitivity analysis method can optimize the calculation process according to Gaussian quadrature and high-dimensional model representation.
7. The boundary condition determination method according to claim 1, characterized in that: The statistical method is a Monte Carlo simulation method.
8. The boundary condition determination method according to claim 1, characterized in that: In step S5, a multi-objective optimization algorithm is used to iteratively update the boundary conditions; the multi-objective optimization algorithm includes a genetic algorithm or a particle swarm optimization algorithm.
9. A boundary condition determination system for a hot rod, characterized in that: include: a memory for storing instructions executable by a processor; A processor is used to execute the instructions to implement the boundary condition determination method of the hot rod as described in any one of claims 1-8.
10. A computer readable medium storing computer program code, characterized in that: When the computer program code is executed by a processor, the computer program code implements the boundary condition determination method of the hot rod according to any one of claims 1 to 8.