Seismic analysis method, system, terminal and medium for nuclear power plant reactor fuel assembly

Abstract

The present invention discloses a method, system, terminal and medium for seismic analysis of a nuclear power plant reactor fuel assembly, and relates to the technical field of reactor seismic analysis. The key points of the technical scheme are: inputting the design acceleration response spectrum into a conversion program to generate a corresponding time history, and adjusting the response spectrum of the intermediate process in real time to obtain the earthquake acceleration time history; inputting the earthquake acceleration time history into the reactor structure system model for calculation to obtain the seismic time history of the hanging basket enclosure and the upper and lower cores; inputting the seismic time history of the hanging basket enclosure and the upper and lower cores into the seismic load distribution model for calculation to obtain the seismic load of each part of the fuel assembly; inputting the seismic load of the fuel assembly together with other non-seismic loads into the stress analysis program to obtain the fuel assembly benchmark accident analysis results. The present invention can obtain an earthquake acceleration time history that meets the specification parameters and ensures a reasonable safety margin, improves the work efficiency of the seismic analysis of the fuel assembly, and reduces the errors and omissions in manual data transmission and load combination.

Description

Technical Field

[0001] The present invention relates to the technical field of reactor seismic analysis, and more specifically, to a method, system, terminal and medium for seismic analysis of a nuclear power plant reactor fuel assembly. Background Art

[0002] In the seismic analysis of the Hualong One third-generation nuclear power plant, the peak ground acceleration of the site seismic design was increased from 0.2g to 0.3g, resulting in the stress strength margin of the initial design of the reactor fuel assembly exceeding the limit. Therefore, it is necessary to find seismic inputs that meet the requirements of the specifications and ensure a reasonable safety margin, and to carry out multiple rounds of fuel assembly seismic analysis based on the seismic inputs. In the seismic analysis of the fuel assembly, the fuel assembly, as a sub-component of the reactor system, involves the transformation of the seismic response spectrum of the reactor system support position to the seismic acceleration time history, the establishment of the reactor system analysis model and seismic analysis (seismic input calculation of the fuel assembly), the establishment of the fuel assembly dynamic analysis model and seismic response load calculation, different types of load combinations, component stress analysis and evaluation, etc.; the manual analysis process is extremely complicated, and the amount of input / output data transmitted between the software is large, the manual working method is inefficient, and the probability of data transmission errors is high. In addition, the calculations involving multiple rounds are extremely cumbersome and time-consuming.

[0003] At present, the seismic analysis process of fuel assemblies at home and abroad is basically similar, and both are extremely cumbersome, such as the accident analysis of the Qinshan Phase II fuel assembly loss of coolant accident LOCA and earthquake SSE by Xiao Zhong et al. and the safety analysis of fuel assemblies under earthquake plus LOCA by Zhou Yunqing et al. In terms of software use, the seismic analysis of the fuel assemblies of the US AP1000 reactor type requires three software: first use the DEPLIN2 program to convert the spectrum to the time history, perform manual screening of the time history, then use the ANSYS software to perform reactor coolant system and reactor seismic analysis, obtain the input of the seismic analysis of the fuel assembly, and then use the WEGAP software to perform seismic analysis of the fuel assembly to obtain the deformation of the fuel assembly, and finally use the ANSYS software to perform stress analysis based on the deformation to complete the analysis and evaluation; for the seismic analysis of the fuel assemblies of the French M310 reactor type, three software are also required: first use the FACS program to convert the spectrum to the time history, perform manual screening of the time history, then use the SYSTUS software to perform reactor seismic analysis, obtain the input of the seismic analysis of the fuel assembly, and then use the CASAC to perform seismic analysis and stress analysis of the fuel assembly to complete the evaluation analysis. In addition, in the conversion of the earthquake floor response spectrum at the support position of the reactor system to the earthquake acceleration time history, on the one hand, the specifications are upgraded and the time history conversion spectrum needs to meet the requirements of the upgraded specifications, and on the other hand, the basic requirement of a reasonable safety margin must be guaranteed, and manual search is extremely cumbersome.

[0004] However, there is no related technology that meets the above requirements in public reports at home and abroad. Therefore, how to study and design a nuclear power plant reactor fuel assembly seismic analysis method, system, terminal and medium that can overcome the above defects is a problem that we urgently need to solve. Summary of the invention

[0005] In order to address the deficiencies in the prior art, the purpose of the present invention is to provide a method, system, terminal and medium for seismic analysis of nuclear power plant reactor fuel assemblies, which can obtain earthquake acceleration time histories that meet specification parameters and ensure a reasonable safety margin, while improving the work efficiency of seismic analysis of fuel assemblies, reducing the manual workload of seismic analysis, reducing the probability of errors in the analysis process, and avoiding errors and omissions that may occur in manual data transmission and load combinations.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions:

[0007] In a first aspect, a method for seismic analysis of a nuclear power plant reactor fuel assembly is provided, comprising the following steps:

[0008] Input the design acceleration response spectrum into the conversion program to generate the corresponding time history, and adjust the response spectrum of the intermediate process in real time to obtain the earthquake acceleration time history;

[0009] A reactor structure system model is established according to the reactor structure design, and the earthquake acceleration time history is input as an excitation into the reactor structure system model to calculate the reactor structure load distribution, and the earthquake time history of the hanging basket enclosure and the upper and lower cores is obtained;

[0010] The seismic load distribution model of the fuel assembly is established according to the fuel assembly design and the structural distribution of the fuel assembly. The seismic time history of the hanging basket and the upper and lower cores is used as the excitation input into the seismic load distribution model to calculate the load distribution of the fuel assembly and obtain the seismic load of each part of the fuel assembly.

[0011] The seismic load of the fuel assembly is input into the stress analysis program together with other non-seismic loads to obtain the fuel assembly benchmark accident analysis results.

[0012] Furthermore, the process of obtaining the earthquake acceleration time history is specifically as follows:

[0013] Input the designed acceleration response spectrum into the conversion program to generate the corresponding time history;

[0014] Count the various indicators of the corresponding time series that meet the standard parameters and obtain statistical data;

[0015] Statistical data is used to determine whether the frequency spectrum corresponding to a single frequency point should be adjusted to adjust the design acceleration response spectrum, and the first time course that meets the specification parameters is obtained after feedback adjustment iteration;

[0016] The target power spectrum density is calculated based on the design acceleration response spectrum, and it is determined whether the power spectrum density of the first time history in the [0.3, 24] Hz frequency band exceeds the reference power spectrum density determined by the target power spectrum density;

[0017] The first time history exceeding the reference power spectral density is taken as the earthquake acceleration time history.

[0018] Furthermore, the adjustment formula of the designed acceleration response spectrum is specifically:

[0019]

[0020] Sa'(ω)=A k (ω)×S a (ω)

[0021] Among them, A k (ω) represents the adjustment coefficient; S ah (ω) represents the time-course calculation spectrum; S a (ω) represents the design acceleration response spectrum; Sa'(ω) represents the adjustment spectrum of the design acceleration response spectrum; ω represents the circular frequency.

[0022] Furthermore, the calculation formula of the target power spectral density is specifically:

[0023]

[0024] Where Psd(ω) represents the target power spectrum density; ξ represents the damping ratio; S a (ω) represents the design acceleration response spectrum; T d represents the duration of a strong earthquake; P represents the exceedance probability; ω represents the circular frequency.

[0025] Furthermore, the reference power spectral density is the product of the target power spectral density and a percentage threshold, and the percentage threshold is ≥0.8.

[0026] Furthermore, the earthquake acceleration time history is converted into a format that can be directly read into finite element software.

[0027] Furthermore, the process of obtaining the fuel assembly benchmark accident analysis results is specifically as follows:

[0028] According to the algorithm of film stress and bending stress of fuel assembly guide tube, a stress analysis program for analyzing components is established;

[0029] The stress analysis program was used to perform stress analysis on the finite element model and the benchmark accident analysis results of the fuel assembly were obtained.

[0030] Secondly, a nuclear power plant reactor fuel assembly seismic analysis system is provided, including:

[0031] The time history generation module is used to input the design acceleration response spectrum into the conversion program to generate the corresponding time history, and adjust the response spectrum of the intermediate process in real time to obtain the earthquake acceleration time history;

[0032] The reactor analysis module is used to establish a reactor structure system model according to the reactor structure design, and to input the earthquake acceleration time history as an excitation into the reactor structure system model to perform reactor structure load distribution calculations, and obtain the seismic time history of the hanging basket enclosure and the upper and lower cores;

[0033] The assembly seismic analysis module is used to establish a seismic load distribution model for the fuel assembly according to the fuel assembly design and the structural distribution of the fuel assembly, and to calculate the fuel assembly load distribution after inputting the seismic time history of the hanging basket enclosure and the upper and lower cores into the seismic load distribution model as excitation, so as to obtain the seismic load of each part of the fuel assembly;

[0034] The component evaluation and analysis module is used to input the seismic load of the fuel assembly together with other non-seismic loads into the stress analysis program to obtain the fuel assembly benchmark accident analysis results.

[0035] In a third aspect, a computer terminal is provided, 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, the method for seismic analysis of a nuclear power plant reactor fuel assembly as described in any one of the first aspects is implemented.

[0036] In a fourth aspect, a computer-readable medium is provided, on which a computer program is stored, and the computer program is executed by a processor to implement the method for seismic analysis of a nuclear power plant reactor fuel assembly as described in any one of the first aspects.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. The seismic analysis method for nuclear power plant reactor fuel assembly provided by the present invention processes the specification parameter requirements of the nuclear power plant earthquake acceleration time history in a programmed manner, realizes the automation of converting the earthquake response spectrum into the acceleration time history, avoids a large amount of repeated manual labor caused by manual selection, and achieves the effect of reducing the workload;

[0039] 2. The calculation results of the professional program provided by the present invention are automatically converted into the input of the general program, which can avoid the errors that may be caused by manual conversion and improve the accuracy of data conversion;

[0040] 3. The automated method for stress analysis load combination provided by the present invention can avoid omissions that may be caused by manual combination, and greatly reduce the workload of manual load combination;

[0041] 4. The stress assessment automation provided by the present invention can greatly improve work efficiency and reduce the probability of manual errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0043] Figure 1 is a flow chart in an embodiment of the present invention;

[0044] Figure 2 is a system block diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0046] Example 1: Seismic analysis method for nuclear power plant reactor fuel assembly, such as Figure 1 As shown, the following steps are included:

[0047] Step S1: input the design acceleration response spectrum into the conversion program to generate the corresponding time history, and adjust the response spectrum of the intermediate process in real time to obtain the earthquake acceleration time history that meets the requirements of the specification and ensures a reasonable safety margin; wherein the earthquake acceleration time history is converted into a format that can be directly read by the finite element software to provide acceleration time history input for the seismic time history analysis of the reactor system;

[0048] Step S2: establishing a reactor structure system model according to the reactor structure design, and inputting the earthquake acceleration time history into the reactor structure system model as an excitation to perform reactor structure load distribution calculation, and obtaining the seismic time history of the hanging basket enclosure and the upper and lower cores;

[0049] Step S3: establishing a seismic load distribution model for the fuel assembly according to the fuel assembly design and the structural distribution of the fuel assembly, and inputting the seismic time history of the hanging basket enclosure and the upper and lower cores into the seismic load distribution model as excitations to perform fuel assembly load distribution calculations, and obtain seismic loads on various parts of the fuel assembly;

[0050] Step S4: Input the seismic load of the fuel assembly together with other non-seismic loads into the stress analysis program to obtain the fuel assembly benchmark accident analysis results.

[0051] It should be noted that step S2 and step S3 in the above method can be implemented after being optimized based on the existing functions of ANSYS software.

[0052] The specific process of obtaining the earthquake acceleration time history is as follows: input the design acceleration response spectrum into the conversion program to generate the corresponding time history; count the indicators of the corresponding time history that meet the specification parameters to obtain statistical data; use the statistical data to determine whether the frequency spectrum corresponding to a single frequency point adjusts the design acceleration response spectrum, and obtain the first time history that meets the specification parameters after feedback adjustment iteration;

[0053] The target power spectral density is calculated based on the design acceleration response spectrum, and it is determined whether the power spectral density of the first time history in the [0.3, 24] Hz frequency band exceeds the benchmark power spectral density determined by the target power spectral density; the first time history that exceeds the benchmark power spectral density is taken as the earthquake acceleration time history.

[0054] The adjustment formula for the design acceleration response spectrum is as follows:

[0055]

[0056] Sa'(ω)=A k (ω)×S a (ω)

[0057] Among them, A k (ω) represents the adjustment coefficient; S ah (ω) represents the time-course calculation spectrum; S a (ω) represents the design acceleration response spectrum; Sa'(ω) represents the adjustment spectrum of the design acceleration response spectrum; ω represents the circular frequency.

[0058] The calculation formula of the target power spectral density is as follows:

[0059]

[0060] Where Psd(ω) represents the target power spectrum density; ξ represents the damping ratio; S a (ω) represents the design acceleration response spectrum; T d It represents the duration of a strong earthquake, such as 15s; P represents the exceedance probability, such as 0.85; ω represents the circular frequency.

[0061] The reference power spectrum density is the product of the target power spectrum density and the percentage threshold. The percentage threshold is ≥0.8, such as 0.8.

[0062] The process of obtaining the benchmark accident analysis results of the fuel assembly is as follows: according to the algorithm of the film stress and bending stress of the guide tube of the fuel assembly, a stress analysis program for the analysis component is established; the stress analysis program is used to perform stress analysis on the finite element model to obtain the benchmark accident analysis results of the fuel assembly.

[0063] Embodiment 2: A nuclear power plant reactor fuel assembly seismic analysis system, the system is used to implement the nuclear power plant reactor fuel assembly seismic analysis method described in Embodiment 1, such as Figure 2 As shown, it includes a time history generation module, a reactor analysis module, a component seismic analysis module and a component evaluation analysis module.

[0064] Among them, the time history generation module is used to input the design acceleration response spectrum into the conversion program to generate the corresponding time history, and adjust the response spectrum of the intermediate process in real time to obtain the earthquake acceleration time history; the reactor analysis module is used to establish the reactor structure system model according to the reactor structure design, and input the earthquake acceleration time history as the excitation into the reactor structure system model, and then perform the reactor structure load distribution calculation to obtain the earthquake time history of the hanging basket enclosure and the upper and lower cores; the component seismic analysis module is used to establish the seismic load distribution model of the fuel assembly according to the fuel assembly design and the structural distribution form of the fuel assembly, and input the seismic time history of the hanging basket enclosure and the upper and lower cores into the seismic load distribution model as the excitation to perform the fuel assembly load distribution calculation to obtain the seismic load of each part of the fuel assembly; the component evaluation and analysis module is used to input the seismic load of the fuel assembly together with other non-seismic loads into the stress analysis program to obtain the benchmark accident analysis results of the fuel assembly.

[0065] Working principle: The seismic analysis method for reactor fuel assemblies of nuclear power plants provided by the present invention processes the standard parameters and requirements of the earthquake acceleration time history of nuclear power plants in a programmed manner, and can obtain an earthquake acceleration time history that meets the standard parameters and ensures a reasonable safety margin, realizes the automation of converting the earthquake response spectrum into the acceleration time history, reduces the number of rounds and conservatism, improves the work efficiency of seismic analysis and evaluation of fuel assemblies, reduces the manual workload of seismic analysis and evaluation, reduces the error probability in the analysis process, and avoids errors and omissions that may occur in manual data transmission and load combination.

[0066] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0067] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0068] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0069] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0070] The above specific implementation methods further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific implementation methods of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for seismic analysis of a nuclear power plant reactor fuel assembly, characterized in that: The following steps are involved: Input the design acceleration response spectrum into the conversion program to generate the corresponding time history, and adjust the response spectrum of the intermediate process in real time to obtain the earthquake acceleration time history; A reactor structure system model is established according to the reactor structure design, and the earthquake acceleration time history is input as an excitation into the reactor structure system model to calculate the reactor structure load distribution, and the earthquake time history of the hanging basket enclosure and the upper and lower cores is obtained; The seismic load distribution model of the fuel assembly is established according to the design of the fuel assembly and the structural distribution of the fuel assembly. The seismic time history of the hanging basket and the upper and lower cores is used as the excitation input into the seismic load distribution model to calculate the load distribution of the fuel assembly and obtain the seismic load of each part of the fuel assembly. Input the seismic load of the fuel assembly together with other non-seismic loads into the stress analysis program to obtain the fuel assembly benchmark accident analysis results; The process of obtaining the earthquake acceleration time history is specifically as follows: Input the designed acceleration response spectrum into the conversion program to generate the corresponding time history; Count the various indicators of the corresponding time series that meet the standard parameters and obtain statistical data; Statistical data is used to determine whether the frequency spectrum corresponding to a single frequency point should be adjusted to meet the design acceleration response spectrum, and the first time history that meets the specification parameters is obtained after feedback adjustment iterations; The target power spectrum density is calculated based on the design acceleration response spectrum, and it is determined whether the power spectrum density of the first time history in the [0.3, 24] Hz frequency band exceeds the reference power spectrum density determined by the target power spectrum density; The first time history exceeding the reference power spectrum density is taken as the earthquake acceleration time history; The adjustment formula of the design acceleration response spectrum is specifically: Sa'(ω)=A k (ω)×S a (oh) Among them, A k (ω) represents the adjustment coefficient; S ah (ω) represents the time-course calculation spectrum; S a (ω) represents the design acceleration response spectrum; Sa'(ω) represents the adjustment spectrum of the design acceleration response spectrum; ω represents the circular frequency.

2. The method for seismic analysis of a nuclear power plant reactor fuel assembly according to claim 1, characterized in that: The calculation formula of the target power spectral density is specifically: Where Psd(ω) represents the target power spectrum density; ξ represents the damping ratio; S a (ω) represents the design acceleration response spectrum; T d represents the duration of a strong earthquake; P represents the exceedance probability; ω represents the circular frequency.

3. The method for seismic analysis of a nuclear power plant reactor fuel assembly according to claim 1, characterized in that: The reference power spectral density is the product of the target power spectral density and a percentage threshold, and the percentage threshold is ≥0.

8.

4. The method for seismic analysis of a nuclear power plant reactor fuel assembly according to claim 1, characterized in that: The earthquake acceleration time history is converted into a format that can be directly read into finite element software.

5. The method for seismic analysis of a nuclear power plant reactor fuel assembly according to claim 1, characterized in that: The process of obtaining the fuel assembly benchmark accident analysis results is specifically as follows: According to the algorithm of film stress and bending stress of fuel assembly guide tube, a stress analysis program for analyzing components is established; The stress analysis program was used to perform stress analysis on the finite element model and the benchmark accident analysis results of the fuel assembly were obtained.

6. Nuclear power plant reactor fuel assembly seismic analysis system, characterized by: The system is used to implement the nuclear power plant reactor fuel assembly seismic analysis method as described in any one of claims 1 to 5, comprising: The time history generation module is used to input the design acceleration response spectrum into the conversion program to generate the corresponding time history, and adjust the response spectrum of the intermediate process in real time to obtain the earthquake acceleration time history; The reactor analysis module is used to establish a reactor structure system model according to the reactor structure design, and to input the earthquake acceleration time history as an excitation into the reactor structure system model to perform reactor structure load distribution calculations, and obtain the seismic time history of the hanging basket enclosure and the upper and lower cores; The assembly seismic analysis module is used to establish a seismic load distribution model for the fuel assembly according to the fuel assembly design and the structural distribution of the fuel assembly, and to calculate the fuel assembly load distribution after inputting the seismic time history of the hanging basket enclosure and the upper and lower cores into the seismic load distribution model as excitation, so as to obtain the seismic load of each part of the fuel assembly; The component evaluation and analysis module is used to input the seismic load of the fuel assembly together with other non-seismic loads into the stress analysis program to obtain the fuel assembly benchmark accident analysis results.

7. A computer terminal 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, the method for seismic analysis of a nuclear power plant reactor fuel assembly as described in any one of claims 1 to 5 is implemented.

8. A computer readable medium having a computer program stored thereon, characterized in that: The computer program is executed by a processor to implement the nuclear power plant reactor fuel assembly seismic analysis method as described in any one of claims 1 to 5.

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