Accident transient analysis method for nuclear power plant resulting in pellet-cladding interaction

Abstract

The present application relates to a method, apparatus, computer equipment, storage medium, and computer program product for analyzing accident transients in a nuclear power plant resulting in pellet-cladding interaction. The method comprises: obtaining the same xenon strategy for the nuclear thermal system program and the core calculation program; obtaining the initial axial power deviation of the nuclear thermal system program and the core calculation program; obtaining the neutronic parameters of the core calculation program and the nuclear thermal system program when the initial axial power deviations of the core calculation program and the nuclear thermal system program are consistent; correcting the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program; obtaining the boundary conditions of the accident transient process resulting in pellet-cladding interaction based on the corrected neutronic parameters of the nuclear thermal system program; and obtaining the core calculation program power distribution during the accident transient process. This method can effectively reflect the core calculation program power distribution results during the accident transient process resulting in pellet-cladding interaction.

Description

Technical Field

[0001] The present application relates to the field of nuclear reactor technology, and in particular to a method for analyzing transient accidents of a nuclear power plant that cause interaction between a pellet and a cladding, a device for analyzing transient accidents of a nuclear power plant that cause interaction between a pellet and a cladding, a computer device, a storage medium, and a computer program product. Background Art

[0002] The interaction between pellets and cladding refers to the mechanical interaction that may occur between the pellets and the cladding during the use of the fuel rods, as well as the chemical interaction between the fission products in the fuel rods and the cladding. This interaction is caused by nuclear power plant accidents, which cause power distortion, resulting in a reduction in the gap between the pellets and the cladding, or even contact.

[0003] Typically, transient analysis of accident transient processes that result in interaction between the core and the cladding is performed using the nuclear thermal system program and the core calculation program. First, the xenon strategies and initial axial power deviations of the nuclear thermal system program and the core calculation program are adjusted to be consistent. Then, the nuclear thermal system program is used for transient calculations. Feature points of the nuclear power versus time curve obtained by the transient calculation of the nuclear thermal system program are selected, and the parameters at the corresponding moments of the feature points are extracted as boundary input conditions for the core calculation program for transient analysis.

[0004] However, in the above-mentioned traditional transient analysis scheme, only the xenon strategy and initial axial power deviation of the nuclear thermal system program and the core calculation program are adjusted and analyzed, which cannot obtain accurate power distribution results of the core calculation program. Summary of the Invention

[0005] Based on this, it is necessary to provide a method, device, computer equipment, computer-readable storage medium and computer program product for transient analysis of accidents causing interaction between core blocks and cladding in nuclear power plants, which can effectively reflect the power distribution results of the core calculation program during the transient process of accidents causing interaction between core blocks and cladding in order to address the above technical problems.

[0006] In a first aspect, the present application provides a method for analyzing transient events caused by interactions between pellets and cladding in a nuclear power plant. The method comprises:

[0007] Obtain the same xenon strategy for the nuclear thermal system program and the core calculation program;

[0008] According to the same xenon strategy of the nuclear thermal system program and the core calculation program, the initial axial power deviation of the nuclear thermal system program and the initial axial power deviation of the core calculation program are obtained respectively;

[0009] When the initial moment axial power deviation of the core calculation program is consistent with the initial moment axial power deviation of the nuclear thermal system program, obtaining the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program based on the initial moment axial power deviation of the core calculation program and the initial moment axial power deviation of the nuclear thermal system program;

[0010] Correcting the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program to obtain corrected neutronic parameters of the nuclear thermal system program;

[0011] Obtaining boundary conditions of the accident transient process leading to the interaction between the pellet and the cladding based on the modified neutronics parameters of the nuclear thermal system program;

[0012] The accident transient process is subjected to transient analysis based on the boundary conditions, the axial power deviation of the core calculation program at the initial moment, and the neutronic parameters of the core calculation program to obtain the core calculation program power distribution of the accident transient process.

[0013] In one embodiment, obtaining the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program respectively according to the same xenon strategy of the nuclear thermal system program and the core calculation program includes:

[0014] Determine the operational diagram boundaries when the nuclear power plant is in operation;

[0015] Based on the same xenon strategy of the nuclear thermal system program and the core calculation program and the boundary of the operation diagram, xenon oscillations of the nuclear thermal system program and the core calculation program are constructed respectively, so as to obtain the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program respectively. The initial moment axial power deviation is controlled within the boundary of the operation diagram, and the initial moment axial power deviation of the core calculation program remains consistent with the initial moment axial power deviation of the nuclear thermal system program.

[0016] In one embodiment, the step of obtaining the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program based on the initial axial power of the core calculation program and the initial axial power deviation of the core calculation program comprises:

[0017] Based on the axial power deviation at the initial moment, respectively calculating the effective value-added factors corresponding to the nuclear thermal system program and the core calculation program when both the drop control rod and the temperature control rod are in a fully withdrawn state, the effective value-added factor when the temperature control rod is in an insertion limit state, the effective value-added factor when the drop control rod is located at the reactor bottom, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod;

[0018] According to the effective value-added factors of the drop control rod and the temperature control rod in the fully extracted state, the effective value-added factor of the temperature control rod in the insertion limit state, the effective value-added factor of the drop control rod at the bottom of the reactor, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod, respectively corresponding to the nuclear thermal system program and the core calculation program, the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program are obtained respectively.

[0019] In one embodiment, obtaining the core calculation program neutronic parameters and the nuclear thermal system program neutronic parameters according to the effective value-added factors of the drop control rod and the temperature control rod in the fully withdrawn state, the effective value-added factor of the temperature control rod in the insertion limit state, the effective value-added factor of the drop control rod at the bottom of the reactor, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod, respectively, of the nuclear thermal system program and the core calculation program includes:

[0020] According to the effective value-added factors of the drop control rod and the temperature control rod in the fully withdrawn state and the effective value-added factors of the temperature control rod in the insertion limit state corresponding to the nuclear thermal system program and the core calculation program, respectively, the temperature control rod values ​​of the core calculation program and the nuclear thermal system program are obtained respectively;

[0021] Obtaining the drop control rod values ​​of the core calculation program and the nuclear thermal system program, respectively, based on the corresponding effective value-added factors of the drop control rod at the reactor bottom and the effective value-added factors of the temperature control rod at the insertion limit state in the nuclear thermal system program and the core calculation program;

[0022] The Doppler feedback parameters of the core calculation program and the nuclear thermal system program are obtained respectively based on the effective value-added factors of the Doppler feedback corresponding to different power levels and different positions of the temperature control rod, the effective value-added factors when the drop control rod and the temperature control rod are in the fully withdrawn state, and the effective value-added factors when the temperature control rod is in the insertion limit state.

[0023] In one embodiment, the step of correcting the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program to obtain the corrected neutronic parameters of the nuclear thermal system program includes:

[0024] By adjusting the thermodynamic absorption cross-sections of the temperature regulating control rods and the drop control rods in the nuclear thermal program, and the correction coefficient of the Doppler feedback, the neutronic parameters of the nuclear thermal system program are corrected according to the adjusted thermodynamic absorption cross-sections of the temperature regulating control rods and the drop control rods in the nuclear thermal program, and the correction coefficient of the Doppler feedback, so as to correct the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program, thereby obtaining the corrected neutronic parameters of the nuclear thermal system program, wherein the neutronic parameters include the temperature regulating control rod value, the drop control rod value and the Doppler feedback parameter.

[0025] In one embodiment, the neutronic parameters of the nuclear thermal system program are corrected by adjusting the thermodynamic absorption cross sections of the temperature regulating control rods and the drop control rods in the nuclear thermal program and the correction coefficient of the Doppler feedback, so as to correct the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program. The corrected neutronic parameters of the nuclear thermal system program include:

[0026] adjusting the thermodynamic absorption cross section of the temperature control rod of the nuclear thermal system program, and correcting the value of the temperature control rod of the nuclear thermal system program according to the adjusted thermodynamic absorption cross section of the temperature control rod in the nuclear thermal program, so as to correct the value of the temperature control rod of the nuclear thermal system program to be consistent with the value of the temperature control rod of the core calculation program, thereby obtaining a corrected value of the temperature control rod of the nuclear thermal system program;

[0027] After obtaining the corrected nuclear thermal system program temperature adjustment control rod value that is consistent with the core calculation program temperature adjustment control rod value, the nuclear thermal system program drop control rod value is corrected by adjusting the thermal absorption cross section of the nuclear thermal system program drop control rod to correct the nuclear thermal system program drop control rod value to be consistent with the core calculation program drop control rod value, thereby obtaining a corrected nuclear thermal system program drop control rod value;

[0028] After obtaining the nuclear thermal system program drop control rod value that is consistent with the core calculation program drop control rod value, the correction coefficient of the nuclear thermal system Doppler feedback is adjusted and the Doppler feedback of the nuclear thermal system program is corrected to correct the nuclear thermal system program Doppler feedback to be consistent with the core calculation program Doppler feedback, thereby obtaining the corrected nuclear thermal system program Doppler feedback.

[0029] In a second aspect, the present application also provides a device for analyzing transient events caused by interactions between pellets and cladding in a nuclear power plant. The device comprises:

[0030] Strategy acquisition module, used to obtain the same xenon strategy as the nuclear thermal system program and the core calculation program;

[0031] a deviation acquisition module, for respectively acquiring the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program according to the same xenon strategy of the nuclear thermal system program and the core calculation program;

[0032] a parameter acquisition module for acquiring, when the axial power deviation at the initial moment of the core calculation program is consistent with the axial power deviation at the initial moment of the nuclear thermal system program, neutronic parameters of the core calculation program and neutronic parameters of the nuclear thermal system program based on the axial power deviation at the initial moment of the core calculation program and the axial power deviation at the initial moment of the nuclear thermal system program; a parameter correction module for correcting the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program, thereby obtaining corrected neutronic parameters of the nuclear thermal system program;

[0033] a boundary acquisition module, configured to acquire boundary conditions of an accident transient process causing interaction between pellets and cladding based on the modified neutronics parameters of the nuclear thermal system program;

[0034] The transient analysis module is used to perform transient analysis on the accident transient process based on the boundary conditions, the axial power deviation of the core calculation program at the initial moment, and the neutronic parameters of the core calculation program to obtain the core calculation program power distribution of the accident transient process.

[0035] In a third aspect, the present application further provides a computer device. The computer device includes a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are performed:

[0036] Obtain the same xenon strategy for the nuclear thermal system program and the core calculation program;

[0037] According to the same xenon strategy of the nuclear thermal system program and the core calculation program, the initial axial power deviation of the nuclear thermal system program and the initial axial power deviation of the core calculation program are obtained respectively;

[0038] When the initial moment axial power deviation of the core calculation program is consistent with the initial moment axial power deviation of the nuclear thermal system program, obtaining the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program based on the initial moment axial power deviation of the core calculation program and the initial moment axial power deviation of the nuclear thermal system program;

[0039] Correcting the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program to obtain corrected neutronic parameters of the nuclear thermal system program;

[0040] Obtaining boundary conditions of the accident transient process leading to the interaction between the pellet and the cladding based on the modified neutronics parameters of the nuclear thermal system program;

[0041] The accident transient process is subjected to transient analysis based on the boundary conditions, the axial power deviation of the core calculation program at the initial moment, and the neutronic parameters of the core calculation program to obtain the core calculation program power distribution of the accident transient process.

[0042] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the following steps:

[0043] Obtain the same xenon strategy for the nuclear thermal system program and the core calculation program;

[0044] According to the same xenon strategy of the nuclear thermal system program and the core calculation program, the initial axial power deviation of the nuclear thermal system program and the initial axial power deviation of the core calculation program are obtained respectively;

[0045] When the initial moment axial power deviation of the core calculation program is consistent with the initial moment axial power deviation of the nuclear thermal system program, obtaining the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program based on the initial moment axial power deviation of the core calculation program and the initial moment axial power deviation of the nuclear thermal system program;

[0046] Correcting the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program to obtain corrected neutronic parameters of the nuclear thermal system program;

[0047] Obtaining boundary conditions of the accident transient process leading to the interaction between the pellet and the cladding based on the modified neutronics parameters of the nuclear thermal system program;

[0048] The accident transient process is subjected to transient analysis based on the boundary conditions, the axial power deviation of the core calculation program at the initial moment, and the neutronic parameters of the core calculation program to obtain the core calculation program power distribution of the accident transient process.

[0049] In a fifth aspect, the present application further provides a computer program product. The computer program product includes a computer program that, when executed by a processor, implements the following steps:

[0050] Obtain the same xenon strategy for the nuclear thermal system program and the core calculation program;

[0051] According to the same xenon strategy of the nuclear thermal system program and the core calculation program, the initial axial power deviation of the nuclear thermal system program and the initial axial power deviation of the core calculation program are obtained respectively;

[0052] When the initial moment axial power deviation of the core calculation program is consistent with the initial moment axial power deviation of the nuclear thermal system program, obtaining the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program based on the initial moment axial power deviation of the core calculation program and the initial moment axial power deviation of the nuclear thermal system program;

[0053] Correcting the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program to obtain corrected neutronic parameters of the nuclear thermal system program;

[0054] Obtaining boundary conditions of the accident transient process leading to the interaction between the pellet and the cladding based on the modified neutronics parameters of the nuclear thermal system program;

[0055] The accident transient process is subjected to transient analysis based on the boundary conditions, the axial power deviation of the core calculation program at the initial moment, and the neutronic parameters of the core calculation program to obtain the core calculation program power distribution of the accident transient process.

[0056] The above-mentioned accident transient analysis method, device, computer equipment, storage medium and computer program product for the interaction between the core block and the cladding in the nuclear power plant first obtain the same xenon strategy for the nuclear thermal system program and the core calculation program; according to the same xenon strategy for the nuclear thermal system program and the core calculation program, obtain the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program; when the initial moment axial power deviation of the core calculation program is consistent with the initial moment axial power deviation of the nuclear thermal system program and the core calculation program, obtain the neutronic parameters of the core calculation program and the nuclear thermal system program based on the initial moment axial power deviation of the nuclear thermal system program and the core calculation program; correct the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program, and obtain the corrected neutronic parameters of the nuclear thermal system program, which greatly reduces the neutronic parameters caused by the inconsistency of the neutronic parameters. The invention relates to a method for simulating the accident transient process of the nuclear thermal system program and the core calculation program, which causes the deviation between the transient simulations of the nuclear thermal system program and the core calculation program; obtaining the boundary conditions of the accident transient process that causes the interaction between the core block and the cladding according to the neutronic parameters of the corrected nuclear thermal system program; performing transient analysis on the accident transient process based on the boundary conditions, the axial power deviation of the core calculation program at the initial moment and the neutronic parameters of the core calculation program, and obtaining the core calculation program power distribution of the accident transient process. The present application utilizes a three-dimensional core calculation program to simulate the accident transient process that causes the interaction between the core block and the cladding in a nuclear power plant that conforms to the actual situation, and can output the three-dimensional core power distribution at any time, eliminating the deviation of the core calculation program power distribution caused by the artificial selection of limited points, and effectively reflecting the core calculation program power distribution result in the accident transient process that causes the interaction between the core block and the cladding. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 A diagram illustrating an application environment of a method for analyzing an accident transient caused by interaction between pellets and cladding in a nuclear power plant according to an embodiment;

[0058] Figure 2 FIG1 is a flow chart of a method for analyzing transient accidents in a nuclear power plant that result in interaction between pellets and cladding in one embodiment;

[0059] Figure 3 FIG1 is a flow chart of a method for analyzing transient accidents in a nuclear power plant that result in interaction between pellets and cladding in another embodiment;

[0060] Figure 4 FIG1 is a flow chart of a method for analyzing transient accidents in a nuclear power plant that result in interaction between pellets and cladding in another embodiment;

[0061] Figure 5 FIG1 is a flow chart of a method for analyzing transient accidents in a nuclear power plant that result in interaction between pellets and cladding in another embodiment;

[0062] Figure 6A schematic flow chart of a method for analyzing transient accidents in a nuclear power plant resulting in interaction between pellets and cladding in another embodiment;

[0063] Figure 7 This is a waveform diagram of nuclear power changing with time when the nuclear thermal system program and the core calculation program perform transient analysis in a specific application example;

[0064] Figure 8 A structural block diagram of an accident transient analysis device for a nuclear power plant causing interaction between pellets and cladding in one embodiment;

[0065] Figure 9 FIG. 1 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0067] The accident transient analysis method for the interaction between the core and the cladding in a nuclear power plant provided in the embodiment of the present application can be applied to Figure 1In the application environment shown. Among them, the terminal 102 communicates with the server 104 through the network. First, the terminal 102 sends a transient analysis request to the server 104, and the transient analysis request contains the same xenon strategy for the nuclear thermal system program and the core calculation program; the server 104 receives the transient analysis request from the terminal 102, obtains the same xenon strategy for the nuclear thermal system program and the core calculation program, and obtains the initial moment axial power deviation of the nuclear thermal system program and the core calculation program respectively according to the same xenon strategy for the nuclear thermal system program and the core calculation program; when the axial power deviation of the nuclear thermal system program and the core calculation program are the same as the initial moment, based on the initial moment axial power deviation , obtaining the core calculation program neutronic parameters and the nuclear thermal system program neutronic parameters, then correcting the nuclear thermal system program neutronic parameters to be consistent with the core calculation program neutronic parameters, thereby obtaining the corrected nuclear thermal system program neutronic parameters; based on the corrected nuclear thermal system program neutronic parameters, obtaining the boundary conditions for the accident transient process that causes the interaction between the core block and the cladding; performing a transient analysis of the accident transient process based on the boundary conditions, the initial axial power deviation of the core calculation program, and the core calculation program neutronic parameters, thereby obtaining the core calculation program power distribution for the accident transient process. Furthermore, server 104 can also feed back the core calculation program power distribution results for the accident transient process that causes the interaction between the core block and the cladding to terminal 102. Terminal 102 can be, but is not limited to, various personal computers, laptops, smartphones, and tablet computers. Server 104 can be implemented as a standalone server or a server cluster consisting of multiple servers.

[0068] In one embodiment, Figure 2 As shown in the figure, a transient analysis method for the accident of nuclear power plant resulting in the interaction between pellets and cladding is provided. Figure 1 Taking the server 104 in the example as an example, the following steps are included:

[0069] S100, obtaining the same xenon strategy for the nuclear thermal system program and the core calculation program.

[0070] Among them, the xenon strategy refers to changing the core power and control rod positions; the core power is the average power in the core of a nuclear reactor, including the final core power, initial core power and disturbed core power. In this application, the xenon strategy refers to the initial and disturbed core power and control rod positions.

[0071] Specifically, the terminal 102 sends a transient analysis request to the server 104, and the transient analysis request contains the same xenon strategy for the nuclear thermal system program and the core calculation program; the server 104 receives the transient analysis request from the terminal 102 and obtains the same xenon strategy for the nuclear thermal system program and the core calculation program.

[0072] S200 , obtaining an initial moment axial power deviation of the nuclear thermal system program and an initial moment axial power deviation of the core calculation program according to the same xenon strategy of the nuclear thermal system program and the core calculation program.

[0073] Among them, the nuclear thermal system program is a one-dimensional model program, and the core calculation program is a three-dimensional model program. The nuclear thermal system program compresses the three-dimensional core into a one-dimensional axial core, and the nuclear thermal system program has a one- and two-loop control system module, while the core calculation program does not have a one- and two-loop control system module. In addition, the core calculation program can calculate the power distribution of all components of the three-dimensional core; the axial power deviation is the power difference between the upper half of the core and the lower half of the core, reflecting the imbalance of the core axial power distribution based on the rated power level as the reference criterion. If this value exceeds a certain range, it will threaten the safety of the nuclear reactor. Therefore, nuclear power plants usually control the axial power deviation within the boundary range of the operation diagram. At the initial moment, the axial power deviation, that is, the axial power deviation reaches the target value on the boundary of the operation diagram.

[0074] Specifically, after the server 104 receives the same xenon strategy for the nuclear thermal system program and the core calculation program of the terminal 102, it can obtain the axial power deviation at the initial moment when the nuclear thermal system program runs at the boundary of the operation diagram and the axial power deviation at the initial moment when the core calculation program runs at the boundary of the operation diagram according to the same xenon strategy for the nuclear thermal system program and the core calculation program.

[0075] Furthermore, the axial power deviation at the initial moment when the nuclear thermal system program and the core calculation program are respectively running at the boundary of the operation diagram is calculated by obtaining the upper half power and the lower half power of the core in the nuclear thermal system program and the upper half power and the lower half power of the core in the core calculation program, and then calculating the difference between the upper half power and the lower half power of the core according to the axial power deviation.

[0076] S300, when the axial power deviation of the core calculation program at the initial moment is consistent with the axial power deviation of the nuclear thermal system program at the initial moment, the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program are obtained based on the axial power deviation of the core calculation program at the initial moment and the axial power deviation of the nuclear thermal system program at the initial moment.

[0077] Among them, neutron is one of the nucleons that make up the atomic nucleus; neutronics mainly studies the transport behavior of neutrons in matter and some specific nuclear reaction processes of neutrons in matter; neutronic parameters are parameters that need to be used or can be obtained in neutronic research. In this application, neutronic parameters include temperature regulation control rod value, falling control rod value and Doppler feedback parameters.

[0078] Specifically, when the xenon strategy of the nuclear thermal system program and the xenon strategy of the core calculation program remain the same, and the axial power deviation of the nuclear thermal system program at the initial moment searched is also the same as the axial power deviation of the core calculation program at the initial moment, based on the same axial power deviation of the nuclear thermal system program and the core calculation program at the initial moment, the server 104 can obtain the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program.

[0079] S400, correcting the neutronics parameters of the nuclear thermal system program to be consistent with the neutronics parameters of the core calculation program, and obtaining corrected neutronics parameters of the nuclear thermal system program.

[0080] Specifically, even if the xenon strategy of the nuclear thermal system program is the same as that of the core calculation program, and the initial axial power deviation of the nuclear thermal system program is the same as that of the core calculation program, the neutronics parameters of the nuclear thermal system program will be inconsistent with those of the core calculation program. In this case, the neutronics parameters of the nuclear thermal system program need to be corrected to be consistent with those of the core calculation program. Server 104 obtains the corrected neutronics parameters of the nuclear thermal system program.

[0081] S500: Based on the revised neutronics parameters of the nuclear thermal system program, the boundary conditions of the accident transient process that causes the interaction between the pellet and the cladding are obtained.

[0082] Among them, the accident transient process that causes the interaction between the core block and the cladding refers to the transient process of the nuclear power plant accident. During this accident transient process, the power will be distorted, resulting in a reduction in the gap between the core block and the cladding or even contact, thereby generating interaction, that is, the accident transient process of the nuclear power plant will cause the core block and the cladding to interact; the boundary condition refers to the law of change of the variable solved at the boundary of the solution area or its derivative with time and place; the boundary conditions of the accident transient process that causes the interaction between the core block and the cladding in this application include the control rod position, the core inlet temperature and the primary circuit pressure that change with time.

[0083] Specifically, the server 104 performs transient calculations on the nuclear thermal system program based on the neutronic parameters of the nuclear thermal system program that are corrected to be consistent with the neutronic parameters of the core calculation program, and obtains the boundary conditions of the accident transient process that causes the interaction between the core block and the cladding, that is, obtains the control rod position, core inlet temperature and primary circuit pressure that change with time in the accident transient process that causes the interaction between the core block and the cladding as input boundary conditions of the core calculation program.

[0084] S600 , performing transient analysis on the accident transient process based on boundary conditions, the axial power deviation of the core calculation program at the initial moment, and the neutronics parameters of the core calculation program to obtain the core calculation program power distribution of the accident transient process.

[0085] Among them, the power distribution of the core calculation program refers to the power at each position in the core, that is, the heat release rate.

[0086] Specifically, the boundary conditions in the accident transient process that causes the interaction between the core block and the cladding, the axial power deviation at the initial moment of the core calculation program, and the neutronic parameters of the core calculation program are used as inputs of the core calculation program, and a transient calculation module of the core calculation program is introduced. Based on the boundary conditions in the accident transient process, the axial power deviation at the initial moment of the core calculation program, and the neutronic parameters of the core calculation program, the server 104 directly performs transient simulation and analysis on the accident transient process that causes the interaction between the core block and the cladding, and obtains the power at each position of the core calculation program in the accident transient process, that is, the power distribution.

[0087] In the accident transient analysis method of the nuclear power plant causing the interaction between the core block and the cladding, the first step is to obtain the same xenon strategy for the nuclear thermal system program and the core calculation program; according to the same xenon strategy for the nuclear thermal system program and the core calculation program, obtain the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program; when the initial moment axial power deviation of the core calculation program is consistent with that of the nuclear thermal system program, obtain the neutronics parameters of the core calculation program and the nuclear thermal system program based on the initial moment axial power deviation of the nuclear thermal system program and the core calculation program; correct the neutronics parameters of the nuclear thermal system program to be consistent with the neutronics parameters of the core calculation program, and obtain the corrected neutronics parameters of the nuclear thermal system program, which greatly reduces the nuclear thermal system program caused by the different neutronics parameters. The invention relates to a method for analyzing the deviation between transient simulations of the core calculation program and the core calculation program; obtaining the boundary conditions of the accident transient process that causes the interaction between the core block and the cladding according to the neutronic parameters of the corrected nuclear thermal system program; performing transient analysis on the accident transient process based on the boundary conditions, the axial power deviation of the core calculation program at the initial moment and the neutronic parameters of the core calculation program, and obtaining the core calculation program power distribution of the accident transient process. The present application utilizes a three-dimensional core calculation program to simulate the accident transient process that causes the interaction between the core block and the cladding in a nuclear power plant that conforms to actual conditions, and can output the three-dimensional core power distribution at any time, eliminating the deviation of the core calculation program power distribution caused by the artificial selection of limited points, and effectively reflecting the core calculation program power distribution result in the accident transient process that causes the interaction between the core block and the cladding.

[0088] In one embodiment, Figure 3 As shown, S200 includes:

[0089] S220, determining the operation diagram boundary during operation of the nuclear power plant.

[0090] The operating diagram boundary refers to the range that the parameters do not exceed during normal operation of the nuclear power plant. When conducting transient analysis of accidents that cause interaction between the core and the cladding, the operating state of the core needs to be controlled within the range of an operating diagram boundary. Once this range is exceeded, the core performance may deteriorate.

[0091] S240, based on the same xenon strategy and operation diagram boundary of the nuclear thermal system program and the core calculation program, construct the xenon oscillation of the nuclear thermal system program and the core calculation program respectively, so as to obtain the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program respectively. The initial moment axial power deviation is controlled within the operation diagram boundary, and the initial moment axial power deviation of the core calculation program remains consistent with the initial moment axial power deviation of the nuclear thermal system program.

[0092] Among them, xenon oscillation causes the xenon poison concentration in the core to change over a period of time, thereby bringing about a significant change in the axial power distribution of the core. Xenon oscillation is directly related to the safety of reactor operation.

[0093] Specifically, the nuclear thermal system program constructs the xenon oscillation of the nuclear thermal system program by adjusting the xenon strategy, and the core calculation program constructs the xenon oscillation of the core calculation program by adjusting the same xenon strategy as the nuclear thermal system program. The xenon oscillation causes changes in the power of the upper and lower parts of the core, that is, changes in the axial power deviation. At a certain point in time, the axial power deviation will reach the boundary value of the operation diagram, that is, the target value. At this time, the axial power deviation of the nuclear thermal system program at the initial moment and the axial power deviation of the core calculation program at the initial moment can be obtained.

[0094] In this embodiment, by determining the boundaries of the operating diagram during operation of the nuclear power plant, the axial power deviation at the initial moment of the nuclear thermal system program and the axial power deviation at the initial moment of the core calculation program can be better obtained, thereby avoiding exceeding the allowable range of the parameters during operation of the nuclear power plant and causing deterioration of the core performance.

[0095] In one embodiment, Figure 4 As shown, S300 includes:

[0096] S320, when the axial power deviation at the initial moment of the core calculation program is consistent with the axial power deviation at the initial moment of the nuclear thermal system program, based on the axial power deviation at the initial moment, respectively calculate the effective value-added factors of the drop control rod and the temperature control rod corresponding to the nuclear thermal system program and the core calculation program in the fully withdrawn state, the effective value-added factors of the temperature control rod in the insertion limit state, the effective value-added factors of the drop control rod at the bottom of the reactor, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod.

[0097] Among them, the control rod is one of the absorption rods made of neutron-absorbing material in order to control the rate of the chain reaction at a predetermined level, which is used to compensate for fuel consumption and adjust the reaction rate. In this application, the control rod includes a drop control rod and a temperature adjustment control rod. The temperature adjustment control rod is used to adjust the average temperature of the core; the effective multiplication factor refers to the ratio of the number of neutrons in a certain generation to the number of neutrons in the adjacent previous generation during the neutron multiplication process of a multiplication medium of limited size. Since the insertion depth of the control rod will affect the power distribution of the core, this application will limit the movement of the control rod within a certain range under different powers during operation; the insertion limit state is the deepest position of the control rod inserted into the core range; Doppler feedback refers to the change of reactivity introduced by the Doppler effect with the power level, which characterizes the degree to which the reactor deviates from the critical state.

[0098] Specifically, the xenon strategy used by the core calculation program must be the same as the xenon strategy used by the nuclear thermal system program. The nuclear thermal system program uses the xenon strategy to search for the initial axial power deviation. The core calculation program uses the same xenon strategy as the nuclear thermal system program to synchronously search for the initial axial power deviation consistent with the nuclear thermal system program. Based on the initial axial power deviation of the nuclear thermal system program, the effective value-added factor K of the drop control rod and the temperature adjustment control rod in the nuclear thermal system program is calculated in the fully withdrawn state. eff1-1D , the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-1D , the effective incremental factor K of the drop control rod at the bottom of the pile eff3-1D And the effective value-added factor K of Doppler feedback at different power levels and different positions of temperature-adjusted control rods eff-FP-R-1D Based on the initial axial power deviation of the core calculation program and the nuclear thermal system program, the effective value-added factor K of the core calculation program when the drop control rod and the temperature control rod are fully withdrawn is calculated. eff1-3D , the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-3D , the effective incremental factor K of the drop control rod at the bottom of the pile eff3-3D And the effective value-added factor K of Doppler feedback at different power levels and different positions of temperature-adjusted control rods eff-FP-R-3D .

[0099] Furthermore, in the nuclear thermal system code and the core calculation code, the effective multiplication factor K of Doppler feedback at different power levels and different positions of the temperature control rod is eff-FP-R-1D and K eff-FP-R-3D FP refers to different powers, and the temperature control rods R include but are not limited to those located outside the reactor R out And the insertion limit state R in And other different locations.

[0100] S340, according to the effective value-added factors of the drop control rod and the temperature control rod in the fully withdrawn state, the effective value-added factor of the temperature control rod in the insertion limit state, the effective value-added factor of the drop control rod at the bottom of the reactor, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod, respectively, the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program are obtained.

[0101] Specifically, in the core calculation program, according to the effective value-added factor K when the drop control rod and the temperature control rod are in the fully withdrawn state in the core calculation program, eff1-3D , the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-3D , the effective incremental factor K of the drop control rod at the bottom of the pile eff3-3D , Doppler feedback adjusts the effective value-added factor K of the control rod outside the reactor at different power levels and temperatures eff-FP-Rou-3D , the effective value-added factor K of Doppler feedback at different power levels and temperature adjustment control rods in the insertion limit state eff-FP-Rin-3D , obtain the neutronics parameters of the core calculation program; in the nuclear thermal system program, according to the effective value-added factor K of the drop control rod and the temperature control rod in the nuclear thermal system program in the fully withdrawn state eff1-1D , the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-1D , the effective incremental factor K of the drop control rod at the bottom of the pile eff3-1D , Doppler feedback adjusts the effective value-added factor K of the control rod outside the reactor at different power levels and temperatures eff-FP-Rout-1D And the effective value-added factor K of Doppler feedback at different power levels and temperatures when the control rod is at the insertion limit state eff-FP-Rin-1D , obtain the neutronics parameters of the nuclear thermal system program.

[0102] In this embodiment, the neutronic parameters of the core calculation program and the nuclear thermal system program are obtained only after ensuring that the xenon strategies corresponding to the nuclear thermal system program and the core calculation program are the same as the axial power deviation at the initial moment, so that the transient analysis results of the nuclear thermal system program are closer to the results of the core calculation program.

[0103] In one embodiment, Figure 5 As shown, S340 includes:

[0104] S342, according to the effective value-added factors of the drop control rod and the temperature control rod in the fully withdrawn state corresponding to the nuclear thermal system program and the core calculation program, and the effective value-added factors of the temperature control rod in the insertion limit state, respectively, obtain the temperature control rod values ​​of the core calculation program and the nuclear thermal system program.

[0105] Among them, the control rod value is the absolute value of the reactivity change caused by quickly and fully inserting a fully extended control rod into the core in a critical state under given conditions. It is a measure of the efficiency of the control rod in compensating reactivity.

[0106] Specifically, in the nuclear thermal system program, according to the effective value-added factor K when the drop control rod and the temperature control rod are in the fully withdrawn state in the nuclear thermal system program, eff1-1D And the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-1D , get the temperature control rod value ρ of the nuclear thermal system program R-1D =ln(K eff2-1D / K eff1-1D )*10 5 In the core calculation program, the effective value-added factor K is calculated based on the drop control rod and temperature control rod being fully withdrawn in the core calculation program. eff1-3D And the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-3D , obtain the temperature control rod value ρ of the core calculation program R-3D =ln(K eff2-3D / K eff1-3D )*10 5 .

[0107] S344, according to the effective value-added factors of the falling control rod at the bottom of the reactor and the effective value-added factors of the temperature regulating control rod at the insertion limit state corresponding to the nuclear thermal system program and the core calculation program respectively, obtain the falling control rod values ​​of the core calculation program and the nuclear thermal system program respectively.

[0108] Specifically, in the nuclear thermal system program, according to the effective increment factor K of the falling control rod at the bottom of the reactor in the nuclear thermal system program, eff3-1D And the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-1D , get the falling control rod value ρ of the nuclear thermal system program Rod-drop-1D =ln(K eff3-1D / K eff2-1D )*10 5 In the core calculation program, according to the effective value-added factor K of the falling control rod at the bottom of the core calculation program eff3-3D And the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-3D , get the falling control rod value ρ of the core calculation program Rod-drop-3D =ln(K eff3-3D / K eff2-3D )*10 5 .

[0109] S346, according to the effective value-added factors of the Doppler feedback corresponding to the nuclear thermal system program and the core calculation program at different power levels and different positions of the temperature control rod, the effective value-added factors when the drop control rod and the temperature control rod are in the fully withdrawn state, and the effective value-added factors when the temperature control rod is in the insertion limit state, respectively obtain the Doppler feedback parameters of the core calculation program and the nuclear thermal system program.

[0110] Specifically, in the nuclear thermal system program, when the temperature control rod is outside the reactor, the effective value-added factor K of the temperature control rod outside the reactor at different power levels and temperature is calculated based on the Doppler feedback in the nuclear thermal system program. eff-FP-Rout-1D And the effective value-added factor K when the drop control rod and temperature control rod are fully withdrawn eff1-1D , calculate the Doppler feedback parameter ρ of the nuclear thermal system program Dopp-1D =ln(K eff-FP-Rout-1D / K eff1-1D )*10 5 In the core calculation program, when the temperature control rod is outside the reactor, the effective value-added factor K at different power levels and temperature control rods outside the reactor is calculated based on the Doppler feedback in the core calculation program. eff-FP-Rout-3D And the effective value-added factor K when the drop control rod and temperature control rod are fully withdrawn eff1-3D , calculate the Doppler feedback parameter ρ of the core calculation program Dopp-3D =ln(K eff-FP-Rout-3D / K eff1-3D )*10 5 In the nuclear thermal system program, when the temperature control rod is in the insertion limit state, the effective value-added factor K at different power levels and the temperature control rod is in the insertion limit state according to the Doppler feedback in the nuclear thermal system program eff-FP-Rin-1D And the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-1D , obtain the Doppler feedback parameter ρ of the nuclear thermal system program Dopp-1D =ln(K eff-FP-Rin-1D / K eff2-1D )*10 5 In the core calculation program, when the temperature control rod is in the insertion limit state, the effective value-added factor K at different power levels and the temperature control rod is in the insertion limit state according to the Doppler feedback in the core calculation program eff-FP-Rin-3D And the effective value-added factor K when the temperature control rod is at the insertion limit state eff2-3D , obtain the Doppler feedback parameter ρ of the core calculation program Dopp-3D =ln(K eff-FP-Rin-3D / K eff2-3D )*10 5 .

[0111] Furthermore, whether it is the nuclear thermal system program or the core calculation program, to obtain the Doppler feedback parameters at different powers, one only needs to change the value of FP.

[0112] In this embodiment, the neutronics parameters of the core calculation program and the nuclear thermal system program are obtained by calculating the temperature adjustment control rod value, the drop control rod value and the Doppler feedback parameters.

[0113] In one embodiment, the neutronics parameters of the nuclear thermal system program are corrected to be consistent with the neutronics parameters of the core calculation program. The corrected neutronics parameters of the nuclear thermal system program include:

[0114] By adjusting the thermodynamic absorption cross sections of the temperature regulating control rods and the drop control rods in the nuclear thermal program, and the correction coefficients of the Doppler feedback, the neutronic parameters of the nuclear thermal system program are corrected according to the adjusted thermodynamic absorption cross sections of the temperature regulating control rods and the drop control rods in the nuclear thermal program, and the correction coefficients of the Doppler feedback, so as to correct the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program, and obtain the corrected neutronic parameters of the nuclear thermal system program, which include the temperature regulating control rod value, the drop control rod value and the Doppler feedback parameters.

[0115] Specifically, since the neutronic parameters of the nuclear thermal system program change with changes in the thermal absorption cross sections of the temperature regulating control rods and the drop control rods and the correction coefficients of the Doppler feedback, the thermal absorption cross sections of the temperature regulating control rods and the drop control rods and the correction coefficients of the Doppler feedback can be continuously adjusted in the nuclear thermal system program, that is, the neutronic parameters of the core calculation program are used as a reference for the neutronic parameters of the nuclear thermal system program, and the thermal absorption cross sections of the temperature regulating control rods and the drop control rods and the correction coefficients of the Doppler feedback are continuously changed to correct the neutronic parameters of the nuclear thermal system program, so that the neutronic parameters of the nuclear thermal system program are consistent with the neutronic parameters of the core calculation program, and finally the corrected neutronic parameters of the nuclear thermal system program are obtained.

[0116] Furthermore, if the neutronic parameters of the nuclear thermal system program before correction are consistent with the neutronic parameters of the core calculation program, there is no need to correct the neutronic parameters of the nuclear thermal system program, and the neutronic parameters of the nuclear thermal system program that are consistent with the neutronic parameters of the core calculation program can be directly obtained.

[0117] In this embodiment, the neutronic parameters of the nuclear thermal system program are corrected to be consistent with the neutronic parameters of the core calculation program, so that the transient analysis of the nuclear thermal system program is more consistent with the actual situation, and the deviation between the transient simulations of the nuclear thermal system program and the core calculation program due to the difference in neutronic parameters is greatly reduced.

[0118] In one embodiment, Figure 6 As shown, S400 includes:

[0119] S420, by adjusting the thermal absorption cross section of the temperature control rod of the nuclear thermal system program, and correcting the value of the temperature control rod of the nuclear thermal system program according to the thermal absorption cross section of the temperature control rod in the adjusted nuclear thermal program, so as to correct the value of the temperature control rod of the nuclear thermal system program to be consistent with the value of the temperature control rod of the core calculation program, and obtain the corrected value of the temperature control rod of the nuclear thermal system program.

[0120] Specifically, the thermodynamic absorption cross section of the temperature control rod is continuously adjusted in the nuclear thermal system program. Based on different thermodynamic absorption cross sections, the effective value-added factor K of the temperature control rod in the insertion limit state can be changed. eff2-1D , due to the effective value-added factor K of the temperature-adjusted control rod at the insertion limit state eff2-1D The value of the nuclear thermal system program temperature regulation control rod can be obtained, so the value of the nuclear thermal system program temperature regulation control rod can be corrected by the value of the core calculation program temperature regulation control rod. According to the value of the core calculation program temperature regulation control rod, a thermal absorption cross section of the temperature regulation control rod is found to obtain the nuclear thermal system program temperature regulation control rod value that is consistent with the value of the core calculation program temperature regulation control rod.

[0121] S440, after obtaining the corrected nuclear thermal system program temperature adjustment control rod value that is consistent with the core calculation program temperature adjustment control rod value, the nuclear thermal system program drop control rod value is corrected by adjusting the thermal absorption cross-section of the nuclear thermal system program drop control rod and correcting the nuclear thermal system program drop control rod value to be consistent with the core calculation program drop control rod value, thereby obtaining the corrected nuclear thermal system program drop control rod value.

[0122] Specifically, after obtaining the revised nuclear thermal system program temperature control rod value that is consistent with the core calculation program temperature control rod value, the thermal absorption cross section of the falling control rod is continuously adjusted in the nuclear thermal system program. Based on different thermal absorption cross sections, the effective value-added factor K of the falling control rod in the insertion limit state can be changed. eff3-1D , due to the effective incremental factor K based on the falling control rods at the bottom of the pile eff3-1D The value of the nuclear thermal system program drop control rod can be obtained, so the value of the nuclear thermal system program drop control rod can be corrected by the value of the core calculation program drop control rod. At this time, the effective value-added factor of the temperature control rod in the insertion limit state is the effective value-added factor K of the temperature control rod in the insertion limit state obtained when the corrected nuclear thermal system program temperature control rod value consistent with the core calculation program temperature control rod value is obtained. eff2-1D , according to the falling control rod value of the core calculation program, find a thermal absorption cross section of the falling control rod, based on Keff2-1D and K eff3-1D , obtain the nuclear thermal system program drop control rod value that is consistent with the core calculation program drop control rod value.

[0123] S460, after obtaining the nuclear thermal system program drop control rod value that is consistent with the core calculation program drop control rod value, the Doppler feedback of the nuclear thermal system program is corrected by adjusting the correction coefficient of the nuclear thermal system Doppler feedback to correct the nuclear thermal system program Doppler feedback to be consistent with the core calculation program Doppler feedback, and the corrected nuclear thermal system program Doppler feedback is obtained.

[0124] Specifically, after obtaining the Doppler feedback parameters of the nuclear thermal system program that are consistent with the control rod drop value of the core calculation program, the effective value-added factor K of the Doppler feedback at different power levels and different R rod positions is obtained. eff-FP-Rin-1D , K eff-FP-Rout-1D It is related to the correction coefficient of the Doppler feedback, so different Doppler feedbacks can be obtained by continuously adjusting the correction coefficient of the nuclear thermal system Doppler feedback. That is, by finding an appropriate Doppler feedback coefficient, the Doppler feedback of the nuclear thermal system program can be corrected to correct the Doppler feedback of the nuclear thermal system program to be consistent with the Doppler feedback of the core calculation program, and the corrected Doppler feedback of the nuclear thermal system program can be obtained.

[0125] In this embodiment, in the nuclear thermal system program, by changing the thermal absorption cross-section of the temperature regulating control rod, the thermal absorption cross-section of the falling control rod, and the correction coefficient of the Doppler feedback, the neutronic parameters of the nuclear thermal system program that are consistent with the neutronic parameters of the core calculation program can be efficiently obtained.

[0126] In one embodiment, Figure 7 As shown in the figure, after the nuclear thermal system program corrects the neutronic parameters according to the neutronic parameters of the core calculation program, transient analysis is performed on the nuclear thermal system program and the core calculation program respectively. The waveform diagram of the nuclear power changing with time when the nuclear thermal system program and the core calculation program are respectively subjected to transient analysis can be obtained. Among them, the 1D transient simulation is the transient analysis of the nuclear thermal system program, and the 3D transient simulation is the transient analysis of the core calculation program.

[0127] It should be understood that, although the steps in the flowcharts of the above embodiments are shown in sequence as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be performed in other orders. Moreover, at least a portion of the steps in the flowcharts of the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily to be performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0128] Based on the same inventive concept, embodiments of the present application also provide a device for analyzing nuclear power plant accidents that cause pellet-cladding interaction, which is used to implement the aforementioned method for analyzing nuclear power plant accidents that cause pellet-cladding interaction. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more embodiments of the device for analyzing nuclear power plant accidents that cause pellet-cladding interaction can be found in the aforementioned definitions of the method for analyzing nuclear power plant accidents that cause pellet-cladding interaction, and will not be further elaborated here.

[0129] In one embodiment, Figure 8 As shown, a device for analyzing transient events caused by interactions between pellets and cladding in a nuclear power plant is provided, comprising: a strategy adjustment module 100, a parameter acquisition module 200, a parameter correction module 300, a boundary acquisition module 400, and a transient analysis module 500, wherein:

[0130] The strategy acquisition module 100 is used to acquire the same xenon strategy as the nuclear thermal system program and the core calculation program.

[0131] The deviation acquisition module 200 is used to respectively acquire the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program according to the same xenon strategy of the nuclear thermal system program and the core calculation program.

[0132] The parameter acquisition module 300 is used to obtain the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program based on the axial power at the initial moment of the core calculation program and the axial power deviation at the initial moment of the core calculation program when the axial power deviation at the initial moment of the core calculation program is consistent with the axial power deviation at the initial moment of the nuclear thermal system program.

[0133] The parameter correction module 400 is used to correct the neutronics parameters of the nuclear thermal system program to be consistent with the neutronics parameters of the core calculation program, thereby obtaining the corrected neutronics parameters of the nuclear thermal system program.

[0134] The boundary acquisition module 500 is used to obtain the boundary conditions of the accident transient process that causes the interaction between the pellet and the cladding based on the modified neutronics parameters of the nuclear thermal system program.

[0135] The transient analysis module 600 is used to perform transient analysis on the accident transient process based on boundary conditions, the initial axial power deviation of the core calculation program, and the neutronic parameters of the core calculation program to obtain the core calculation program power distribution of the accident transient process.

[0136] In one embodiment, the deviation acquisition module 200 is also used to: determine the operating diagram boundary when the nuclear power plant is in operation; based on the same xenon strategy and operating diagram boundary of the nuclear thermal system program and the core calculation program, construct the xenon oscillation of the nuclear thermal system program and the core calculation program respectively, so as to respectively obtain the axial power deviation of the nuclear thermal system program at the initial moment and the axial power deviation of the core calculation program at the initial moment, and the axial power deviation at the initial moment is controlled within the operating diagram boundary, and the axial power deviation of the core calculation program at the initial moment remains consistent with the axial power deviation of the nuclear thermal system program at the initial moment.

[0137] In one embodiment, the parameter acquisition module 300 is further configured to: when the axial power deviation at the initial moment of the core calculation program is consistent with the axial power deviation at the initial moment of the nuclear thermal system program, calculate, based on the axial power deviation at the initial moment, the effective value-added factors corresponding to the nuclear thermal system program and the core calculation program when both the drop control rod and the temperature control rod are in the fully withdrawn state, the effective value-added factors corresponding to the temperature control rod in the insertion limit state, the effective value-added factors corresponding to the drop control rod at the bottom of the reactor, and the effective value-added factors corresponding to Doppler feedback at different power levels and different positions of the temperature control rod; and obtain the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program according to the effective value-added factors corresponding to the nuclear thermal system program and the core calculation program when both the drop control rod and the temperature control rod are in the fully withdrawn state, the effective value-added factors corresponding to the temperature control rod in the insertion limit state, the effective value-added factors corresponding to the drop control rod at the bottom of the reactor, and the effective value-added factors corresponding to the temperature control rod in the insertion limit state,

[0138] In one embodiment, a parameter calculation module is also included, which is further used to: obtain the temperature control rod values ​​of the core calculation program and the nuclear thermal system program respectively according to the effective value-added factors of the falling control rod and the temperature control rod in the fully extracted state and the effective value-added factors of the temperature control rod in the insertion limit state corresponding to the nuclear thermal system program and the core calculation program respectively; obtain the falling control rod values ​​of the core calculation program and the nuclear thermal system program respectively according to the effective value-added factors of the falling control rod at the bottom of the reactor and the effective value-added factors of the temperature control rod in the insertion limit state corresponding to the nuclear thermal system program and the core calculation program respectively; obtain the Doppler feedback parameters of the core calculation program and the nuclear thermal system program respectively according to the effective value-added factors of the Doppler feedback at different power levels and different positions of the temperature control rod, the effective value-added factors of the falling control rod and the temperature control rod in the fully extracted state and the effective value-added factors of the temperature control rod in the insertion limit state corresponding to the nuclear thermal system program and the core calculation program respectively.

[0139] In one embodiment, the parameter correction module 400 is also used to: adjust the thermal absorption cross-sections of the temperature regulating control rods and the drop control rods in the nuclear thermal program, and the correction coefficient of the Doppler feedback, and correct the neutronic parameters of the nuclear thermal system program according to the adjusted thermal absorption cross-sections of the temperature regulating control rods and the drop control rods in the nuclear thermal program, and the correction coefficient of the Doppler feedback, so as to correct the neutronic parameters of the nuclear thermal system program to be consistent with the neutronic parameters of the core calculation program, and obtain the corrected neutronic parameters of the nuclear thermal system program, which include the temperature regulating control rod value, the drop control rod value and the Doppler feedback parameters.

[0140] In one embodiment, the parameter correction module 400 is further used to: adjust the thermal absorption cross section of the temperature control rod of the nuclear thermal system program, and correct the value of the temperature control rod of the nuclear thermal system program according to the thermal absorption cross section of the temperature control rod in the adjusted nuclear thermal program, so as to correct the value of the temperature control rod of the nuclear thermal system program to be consistent with the value of the temperature control rod of the core calculation program, and obtain the corrected value of the temperature control rod of the nuclear thermal system program; after obtaining the corrected value of the temperature control rod of the nuclear thermal system program that is consistent with the value of the temperature control rod of the core calculation program, by adjusting the value of the temperature control rod of the nuclear thermal system program The thermal absorption cross-section of the drop control rod is adjusted, and the drop control rod value of the nuclear thermal system program is corrected to correct the drop control rod value of the nuclear thermal system program to be consistent with the drop control rod value of the core calculation program, thereby obtaining the corrected drop control rod value of the nuclear thermal system program; after obtaining the drop control rod value of the nuclear thermal system program that is consistent with the drop control rod value of the core calculation program, the Doppler feedback of the nuclear thermal system program is corrected by adjusting the correction coefficient of the nuclear thermal system Doppler feedback, thereby correcting the Doppler feedback of the nuclear thermal system program to be consistent with the Doppler feedback of the core calculation program, thereby obtaining the corrected Doppler feedback of the nuclear thermal system program.

[0141] Each module in the aforementioned apparatus for analyzing transient events in nuclear power plants resulting in pellet-cladding interaction accidents can be implemented in whole or in part through software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in the computer device in the form of software, so that the processor can call and execute the corresponding operations of each module.

[0142] In one embodiment, a computer device is provided. The computer device may be a server, and its internal structure diagram may be as follows: Figure 9 As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, abbreviated as I / O) and a communication interface. The processor, memory and input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store accident transient analysis result data that causes the interaction between the core block and the cladding. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for analyzing accidents that cause the interaction between the core block and the cladding is implemented.

[0143] Those skilled in the art will understand that Figure 9 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0144] In one embodiment, a computer device is further provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0145] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0146] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0147] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0148] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory may include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processor involved in the various embodiments provided herein may be, but are not limited to, a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic unit, a data processing logic unit based on quantum computing, and the like.

[0149] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0150] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for analyzing transient accidents in nuclear power plants resulting in interaction between pellets and cladding, characterized in that: The method comprises: Obtain the same xenon strategy for the nuclear thermal system program and the core calculation program; According to the same xenon strategy of the nuclear thermal system program and the core calculation program, the initial axial power deviation of the nuclear thermal system program and the initial axial power deviation of the core calculation program are obtained respectively; When the initial moment axial power deviation of the core calculation program is consistent with the initial moment axial power deviation of the nuclear thermal system program, obtaining the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program based on the initial moment axial power deviation of the core calculation program and the initial moment axial power deviation of the nuclear thermal system program; adjusting the thermodynamic absorption cross sections of the temperature control rods and the drop control rods, and the correction coefficients of Doppler feedback in the nuclear thermal system program; and correcting the neutronics parameters of the nuclear thermal system program according to the adjusted thermodynamic absorption cross sections of the temperature control rods and the drop control rods, and the correction coefficients of Doppler feedback in the nuclear thermal system program to correct the neutronics parameters of the nuclear thermal system program to be consistent with the neutronics parameters of the core calculation program, thereby obtaining corrected neutronics parameters of the nuclear thermal system program, the neutronics parameters including the temperature control rod value, the drop control rod value, and the Doppler feedback parameter; Obtaining boundary conditions of the accident transient process leading to the interaction between the pellet and the cladding based on the modified neutronics parameters of the nuclear thermal system program; The accident transient process is subjected to transient analysis based on the boundary conditions, the axial power deviation of the core calculation program at the initial moment, and the neutronic parameters of the core calculation program to obtain the core calculation program power distribution of the accident transient process.

2. The method according to claim 1, characterized in that The obtaining of the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program respectively according to the same xenon strategy of the nuclear thermal system program and the core calculation program includes: Determine the operational diagram boundaries when the nuclear power plant is in operation; Based on the same xenon strategy of the nuclear thermal system program and the core calculation program and the boundary of the operation diagram, xenon oscillations of the nuclear thermal system program and the core calculation program are constructed respectively, so as to obtain the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program respectively. The initial moment axial power deviation is controlled within the boundary of the operation diagram, and the initial moment axial power deviation of the core calculation program remains consistent with the initial moment axial power deviation of the nuclear thermal system program.

3. The method according to claim 1, characterized in that When the axial power deviation at the initial moment of the core calculation program is consistent with the axial power deviation at the initial moment of the nuclear thermal system program, obtaining the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program based on the axial power deviation at the initial moment of the core calculation program and the axial power deviation at the initial moment of the nuclear thermal system program includes: When the axial power deviation at the initial moment of the core calculation program is consistent with the axial power deviation at the initial moment of the nuclear thermal system program, based on the axial power deviation at the initial moment, respectively calculating the effective value-added factors corresponding to the nuclear thermal system program and the core calculation program when both the drop control rod and the temperature control rod are in a fully withdrawn state, the effective value-added factor when the temperature control rod is in an insertion limit state, the effective value-added factor when the drop control rod is located at the bottom of the reactor, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod; According to the effective value-added factors of the drop control rod and the temperature control rod in the fully extracted state, the effective value-added factor of the temperature control rod in the insertion limit state, the effective value-added factor of the drop control rod at the bottom of the reactor, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod, respectively corresponding to the nuclear thermal system program and the core calculation program, the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program are obtained respectively.

4. The method according to claim 3, characterized in that The obtaining of the core calculation program neutronics parameters and the nuclear thermal system program neutronics parameters according to the effective value-added factors of the drop control rod and the temperature control rod in the fully withdrawn state, the effective value-added factor of the temperature control rod in the insertion limit state, the effective value-added factor of the drop control rod at the reactor bottom, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod, respectively, of the nuclear thermal system program and the core calculation program includes: According to the effective value-added factors of the drop control rod and the temperature control rod in the fully withdrawn state and the effective value-added factors of the temperature control rod in the insertion limit state corresponding to the nuclear thermal system program and the core calculation program, respectively, the temperature control rod values ​​of the core calculation program and the nuclear thermal system program are obtained respectively; Obtaining the drop control rod values ​​of the core calculation program and the nuclear thermal system program, respectively, based on the corresponding effective value-added factors of the drop control rod at the reactor bottom and the effective value-added factors of the temperature control rod at the insertion limit state in the nuclear thermal system program and the core calculation program; The Doppler feedback parameters of the core calculation program and the nuclear thermal system program are obtained respectively based on the effective value-added factors of the Doppler feedback corresponding to different power levels and different positions of the temperature control rod, the effective value-added factors when the drop control rod and the temperature control rod are in the fully withdrawn state, and the effective value-added factors when the temperature control rod is in the insertion limit state.

5. The method according to claim 1, wherein The step of adjusting the thermodynamic absorption cross sections of the temperature regulating control rods and the drop control rods and the correction coefficient of Doppler feedback in the nuclear thermal system program, and correcting the neutronics parameters of the nuclear thermal system program according to the adjusted thermodynamic absorption cross sections of the temperature regulating control rods and the drop control rods and the correction coefficient of Doppler feedback in the nuclear thermal system program to correct the neutronics parameters of the nuclear thermal system program to be consistent with the neutronics parameters of the core calculation program, wherein the corrected neutronics parameters of the nuclear thermal system program include: By adjusting the thermodynamic absorption cross section of the temperature control rod of the nuclear thermal system program, and correcting the value of the temperature control rod of the nuclear thermal system program according to the adjusted thermodynamic absorption cross section of the temperature control rod of the nuclear thermal program, so as to correct the value of the temperature control rod of the nuclear thermal system program to be consistent with the value of the temperature control rod of the core calculation program, thereby obtaining a corrected value of the temperature control rod of the nuclear thermal system program; After obtaining the corrected nuclear thermal system program temperature adjustment control rod value that is consistent with the core calculation program temperature adjustment control rod value, the nuclear thermal system program drop control rod value is corrected by adjusting the thermal absorption cross section of the nuclear thermal system program drop control rod to correct the nuclear thermal system program drop control rod value to be consistent with the core calculation program drop control rod value, thereby obtaining a corrected nuclear thermal system program drop control rod value; After obtaining the nuclear thermal system program drop control rod value that is consistent with the core calculation program drop control rod value, the Doppler feedback of the nuclear thermal system program is corrected by adjusting the correction coefficient of the nuclear thermal system Doppler feedback to correct the nuclear thermal system program Doppler feedback to be consistent with the core calculation program Doppler feedback, thereby obtaining the corrected nuclear thermal system program Doppler feedback.

6. The method according to claim 1, characterized in that The step of obtaining the boundary conditions of the accident transient process leading to the interaction between the pellet and the cladding according to the modified neutronics parameters of the nuclear thermal system program includes: Based on the corrected neutronics parameters of the nuclear thermal system program, a transient calculation is performed on the nuclear thermal system program to obtain the control rod positions, core inlet temperature, and primary circuit pressure that change with time during the accident transient process that causes the interaction between the core block and the cladding, so as to serve as boundary conditions of the core calculation program.

7. A transient analysis device for accidents in nuclear power plants that cause interaction between pellets and cladding, characterized in that: The device comprises: Strategy acquisition module, used to obtain the same xenon strategy as the nuclear thermal system program and the core calculation program; a deviation acquisition module, for respectively acquiring the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program according to the same xenon strategy of the nuclear thermal system program and the core calculation program; a parameter acquisition module, configured to acquire, when the axial power deviation at the initial moment of the core calculation program is consistent with the axial power deviation at the initial moment of the nuclear thermal system program, neutronic parameters of the core calculation program and neutronic parameters of the nuclear thermal system program based on the axial power at the initial moment of the core calculation program and the axial power deviation at the initial moment of the core calculation program; a parameter correction module, configured to adjust the thermodynamic absorption cross sections of the temperature control rods and the drop control rods in the nuclear thermal system program, and a correction coefficient for Doppler feedback, and to correct the neutronics parameters of the nuclear thermal system program based on the adjusted thermodynamic absorption cross sections of the temperature control rods and the drop control rods in the nuclear thermal system program, and the correction coefficient for Doppler feedback, so as to correct the neutronics parameters of the nuclear thermal system program to be consistent with the neutronics parameters of the core calculation program, thereby obtaining corrected neutronics parameters of the nuclear thermal system program, wherein the neutronics parameters include the temperature control rod value, the drop control rod value, and the Doppler feedback parameter; a boundary acquisition module, configured to acquire boundary conditions of an accident transient process causing interaction between pellets and cladding based on the modified neutronics parameters of the nuclear thermal system program; The transient analysis module is used to perform transient analysis on the accident transient process based on the boundary conditions, the axial power deviation of the core calculation program at the initial moment, and the neutronic parameters of the core calculation program to obtain the core calculation program power distribution of the accident transient process.

8. The device according to claim 7, characterized in that The deviation acquisition module is also used to: determine the operating diagram boundary when the nuclear power plant is in operation; based on the same xenon strategy and the operating diagram boundary of the nuclear thermal system program and the core calculation program, construct the xenon oscillation of the nuclear thermal system program and the core calculation program respectively, so as to respectively obtain the initial moment axial power deviation of the nuclear thermal system program and the initial moment axial power deviation of the core calculation program, the initial moment axial power deviation is controlled within the operating diagram boundary, and the initial moment axial power deviation of the core calculation program remains consistent with the initial moment axial power deviation of the nuclear thermal system program.

9. The device according to claim 7, characterized in that The parameter acquisition module is further used to: when the axial power deviation at the initial moment of the core calculation program is consistent with the axial power deviation at the initial moment of the nuclear thermal system program, based on the axial power deviation at the initial moment, respectively calculate the effective value-added factors of the drop control rod and the temperature control rod corresponding to the nuclear thermal system program and the core calculation program when both are in the fully withdrawn state, the effective value-added factors of the temperature control rod in the insertion limit state, the effective value-added factors of the drop control rod at the bottom of the reactor, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod; and respectively obtain the neutronic parameters of the core calculation program and the neutronic parameters of the nuclear thermal system program according to the effective value-added factors of the drop control rod and the temperature control rod in the fully withdrawn state, the effective value-added factors of the temperature control rod in the insertion limit state, the effective value-added factors of the drop control rod at the bottom of the reactor, and the effective value-added factors of Doppler feedback at different power levels and different positions of the temperature control rod corresponding to the nuclear thermal system program and the core calculation program.

10. The device according to claim 9, characterized in that The device further includes a parameter calculation module, the parameter calculation module being configured to obtain temperature control rod values ​​for the core calculation program and the core calculation program, respectively, based on effective value-added factors of the drop control rod and the temperature control rod in a fully withdrawn state and an effective value-added factor of the temperature control rod in an insertion limit state, corresponding to the core calculation program and the core calculation program, respectively. Obtaining the drop control rod values ​​of the core calculation program and the nuclear thermal system program, respectively, based on the corresponding effective value-added factors of the drop control rod at the reactor bottom and the effective value-added factors of the temperature control rod at the insertion limit state in the nuclear thermal system program and the core calculation program; The Doppler feedback parameters of the core calculation program and the nuclear thermal system program are obtained respectively based on the effective value-added factors of the Doppler feedback corresponding to different power levels and different positions of the temperature control rod, the effective value-added factors when the drop control rod and the temperature control rod are in the fully withdrawn state, and the effective value-added factors when the temperature control rod is in the insertion limit state.

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