Method and apparatus for determining a lead factor for a nuclear reactor pressure vessel

Abstract

The embodiment of the application provides a kind of nuclear reactor pressure vessel advance factor determination method and device, belong to nuclear reactor technical field.The method comprises: obtaining the first relative power of the first fuel assembly in the first reactor, and the second relative power of the second fuel assembly in the first reactor;Determine the first contribution share of the fast neutron flux at the neutron detector in the irradiation supervision tube of the first fuel assembly, and determine the second contribution share of the fast neutron flux at the flux peak position of the pressure vessel of the second fuel assembly;According to the first relative power, the second relative power, the first contribution share and the second contribution share, determine the advance factor of the pressure vessel.The embodiment of the application can reduce the calculation cost of advance factor.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nuclear reactors, in particular to a method and device for determining a lead factor of a nuclear reactor pressure vessel. BACKGROUND

[0002] The reactor pressure vessel (RPV) is the main pressure-bearing equipment of a nuclear reactor, is the second safety barrier for preventing the spread of radioactivity and a primary loop pressure boundary, and cannot be replaced during the service life of the reactor, thus playing a crucial role in the safety of a nuclear power plant and the service life of the power plant.

[0003] The irradiation surveillance tube is a device for supervising and predicting changes in the material quality of the reactor pressure vessel material after being irradiated by neutrons. Since the irradiation surveillance tube is close to the reactor core, it is subjected to stronger neutron irradiation than the pressure vessel, and thus can predict the degree of irradiation damage to the material quality of the pressure vessel. During the design service life of the reactor, the irradiation surveillance tube can be extracted during the scheduled shutdown and refueling period. By testing and analyzing the irradiation surveillance tube, the tendency of the material quality of the reactor pressure vessel to deteriorate can be determined.

[0004] The lead factor represents the ratio of the fast neutron fluence at the neutron detector in the irradiation surveillance tube to the maximum fast neutron fluence at the inner surface and 1 / 4 thickness of the pressure vessel, and is an important basis for developing an irradiation surveillance program for a nuclear power plant. Based on the lead factor, the extraction time of the irradiation surveillance tube can be determined.

[0005] At present, a large-scale particle transport model of the reactor usually needs to be established, and operations are performed on the particle transport model to obtain the lead factor. In this process, a large amount of computing resources and computing time are consumed, and there is a problem of high computing cost. SUMMARY

[0006] The main purpose of the embodiments of the present application is to provide a method and device for determining a lead factor of a nuclear reactor pressure vessel, which aims to reduce the computing cost of the lead factor.

[0007] To achieve the above purpose, a first aspect of the embodiments of the present application provides a method for determining a lead factor of a nuclear reactor pressure vessel, and the method comprises:

[0008] obtaining a first relative power of a first fuel assembly in a first reactor and a second relative power of a second fuel assembly in the first reactor, the first fuel assembly being a fuel assembly with a distance less than a first preset value from the irradiation surveillance tube, and the second fuel assembly being a fuel assembly with a distance less than a second preset value from the pressure vessel;

[0009] determining a first contribution share of the first fuel assembly to a fast neutron fluence at a neutron detector inside the irradiation monitoring tube, and determining a second contribution share of the second fuel assembly to a fast neutron fluence at a fluence peak location of the pressure vessel;

[0010] determining an advance factor of the pressure vessel according to the first relative power, the second relative power, the first contribution share and the second contribution share.

[0011] To achieve the above object, a second aspect of embodiments of the present application provides a nuclear reactor pressure vessel advance factor determination device, the device comprising:

[0012] a power obtaining module configured to obtain a first relative power of a first fuel assembly in a first reactor and a second relative power of a second fuel assembly in the first reactor, the first fuel assembly being a fuel assembly with a distance to an irradiation monitoring tube less than a first preset value, and the second fuel assembly being a fuel assembly with a distance to a pressure vessel less than a second preset value;

[0013] a share determining module configured to determine a first contribution share of the first fuel assembly to a fast neutron fluence at a neutron detector inside the irradiation monitoring tube, and determine a second contribution share of the second fuel assembly to a fast neutron fluence at a fluence peak location of the pressure vessel;

[0014] an advance factor determining module configured to determine an advance factor of the pressure vessel according to the first relative power, the second relative power, the first contribution share and the second contribution share.

[0015] To achieve the above object, a third aspect of embodiments of the present application provides an electronic device, the electronic device comprising a memory and a processor, the memory storing a computer program, and the processor implementing the nuclear reactor pressure vessel advance factor determination method of the first aspect when executing the computer program.

[0016] To achieve the above object, a fourth aspect of embodiments of the present application provides a computer readable storage medium, the computer readable storage medium storing a computer program, and the computer program implementing the nuclear reactor pressure vessel advance factor determination method of the first aspect when executed by a processor.

[0017] To achieve the above object, a fifth aspect of embodiments of the present application provides a computer program product, instructions in the computer program product being executed by a processor of an electronic device as described in the third aspect, so that the electronic device executes the nuclear reactor pressure vessel advance factor determination method as described in the first aspect.

[0018] The method and device for determining a lead factor of a nuclear reactor pressure vessel provided in the application obtain a first relative power of a first fuel assembly in a first reactor and a second relative power of a second fuel assembly in the first reactor, determine a first contribution share of the first fuel assembly to a fast neutron flux at a neutron detector in an irradiation monitoring tube, and determine a second contribution share of the second fuel assembly to a fast neutron flux at a peak position of the pressure vessel, and then determine the lead factor of the pressure vessel according to the first relative power, the second relative power, the first contribution share and the second contribution share. Through the foregoing steps, the lead factor of the pressure vessel in the first reactor can be simply and quickly determined according to the first relative power, the second relative power, the first contribution share and the second contribution share of the first reactor, and the calculation cost of the lead factor is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a flowchart of a method for determining a lead factor of a nuclear reactor pressure vessel provided in an embodiment of the application;

[0020] Figure 2 is another flowchart of a method for determining a lead factor of a nuclear reactor pressure vessel provided in an embodiment of the application;

[0021] Figure 3 is a structural schematic diagram of a device for determining a lead factor of a nuclear reactor pressure vessel provided in an embodiment of the application;

[0022] Figure 4 is a hardware structural schematic diagram of an electronic device provided in an embodiment of the application. DETAILED DESCRIPTION

[0023] In order to make the objectives, technical solutions and advantages of the application clearer, the application is further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the application and not intended to limit the application.

[0024] It should be noted that although the functional modules are divided in the device schematic diagram and the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a manner different from the module division in the device or the order in the flowchart. The terms "first", "second", etc. in the specification and claims and the above-described drawings are used to distinguish similar objects and do not necessarily describe a specific order or sequence.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the application belongs. The terms used herein are only for the purpose of describing the embodiments of the application and are not intended to limit the application.

[0026] First, the meanings of several terms involved in the present application are explained:

[0027] Reactor: a device that converts nuclear energy into heat or other forms of energy by precisely controlling the speed and scale of nuclear fission reactions, usually consisting of a core, a coolant system, a moderator system, a control and protection system, a shielding system, and a radiation monitoring system.

[0028] Core: the core component of a reactor, used to generate the required heat source. The core includes a plurality of fuel assemblies arranged in a certain order and spacing. The plurality of fuel assemblies can be used to load nuclear fuel and generate nuclear fission to generate heat.

[0029] Irradiation monitoring tube: a component used to monitor and predict changes in the material of the pressure vessel after irradiation. During the service life of the reactor, irradiation monitoring tubes are periodically provided and performance tests and analysis are performed to obtain the material degradation trend of the reactor pressure vessel.

[0030] Pressure vessel: a closed container used to house the reactor and withstand the operating pressure of the reactor. The pressure vessel can form the pressure boundary of the high-pressure coolant together with the primary circuit piping, ensuring that the nuclear fission reaction of the nuclear fuel takes place in a safe and sealed space.

[0031] To solve the problems of the prior art, the present application provides a nuclear reactor pressure vessel lead factor determination method and device, which is specifically described by the following embodiments. First, the nuclear reactor pressure vessel lead factor determination method in the present application is described.

[0032] The nuclear reactor pressure vessel lead factor determination method provided by the present application relates to the technical field of nuclear reactors. The nuclear reactor pressure vessel lead factor determination method provided by the present application can be applied in a terminal, can be applied in a server, and can be software running in a terminal or a server. In some embodiments, the terminal can be a smartphone, a tablet computer, a notebook computer, a desktop computer, etc.; the server can be configured as a standalone physical server, or as a server cluster or distributed system composed of multiple physical servers, or as a cloud server providing cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDNs, and basic cloud computing services such as big data and artificial intelligence platforms; the software can be an application that implements the nuclear reactor pressure vessel lead factor determination method, but is not limited to the above forms.

[0033] The application is operable in a variety of general purpose or special purpose computer systems environments or configurations. Examples of well known computing systems, environments, and / or configurations that can be suitable for use with the application include personal computers, server computers, handheld or laptop devices, tablet devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like. The application can be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, and the like, that perform particular tasks or implement particular abstract data types. The application can also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules can be located in both local and remote computer storage media including memory storage devices.

[0034] Figure 1 is a flowchart of a method for determining a lead factor of a nuclear reactor pressure vessel provided by an embodiment of the application, Figure 1 The method in the above embodiment can include, but is not limited to, steps 101 to 103.

[0035] In step 101, a first relative power of a first fuel assembly in a first reactor and a second relative power of a second fuel assembly in the first reactor are obtained, the first fuel assembly being a fuel assembly with a distance to an irradiation monitoring tube less than a first preset value, and the second fuel assembly being a fuel assembly with a distance to a pressure vessel less than a second preset value.

[0036] The first reactor is a reactor for which a lead factor of a pressure vessel is to be determined, and includes a core, a power measuring device, an irradiation monitoring tube, and a pressure vessel. For a first reactor in a running state, a radial power distribution of the first reactor can be measured by the power measuring device. For a first reactor in a non-running state, the radial power distribution can be determined according to a design value in a core fuel management scheme of the first reactor.

[0037] The core includes a plurality of fuel assemblies, which include first fuel assemblies, second fuel assemblies, and other fuel assemblies. The first fuel assemblies are m groups of fuel assemblies with a distance to the irradiation monitoring tube less than a first preset value. The second fuel assemblies are n groups of fuel assemblies with a distance to the pressure vessel less than a second preset value. Specifically, m and n are both integers greater than or equal to 1, and m and n can take the same value or different values. Generally, the first fuel assemblies (i.e., the m groups of fuel assemblies) should contribute an amount of fast neutron fluence at the target point not less than a first preset proportion of the fast neutron fluence at the target point, for example, 99%. Also, the second fuel assemblies (i.e., the n groups of fuel assemblies) should contribute an amount of fast neutron fluence at the target point not less than a second preset proportion of the fast neutron fluence at the target point. The first preset proportion and the second preset proportion can be the same or different, for example, both the first preset proportion and the second preset proportion can be 99%. The target point can be at a neutron detector inside the irradiation monitoring tube or at a fluence peak position of the pressure vessel. The distance of the first fuel assemblies to the irradiation monitoring tube can be specifically the distance between the first fuel assemblies and the neutron detector inside the irradiation monitoring tube. The distance of the second fuel assemblies to the pressure vessel can be specifically the distance between the second fuel assemblies and the fluence peak position of the pressure vessel. The first preset value can be determined according to the value of m and the spacing between the fuel assemblies. Similarly, the second preset value can be determined according to the value of n and the spacing between the fuel assemblies.

[0038] The radial power distribution can indicate the positions of the fuel assemblies in the first reactor and the power of the fuel assemblies. After obtaining the radial power distribution of the first reactor and determining the first fuel assemblies and the second fuel assemblies in the first reactor, the electronic device can obtain a first relative power P i of the first fuel assemblies in the first reactor and a second relative power P j of the second fuel assemblies in the first reactor based on the radial power distribution of the first reactor, the distribution positions of the first fuel assemblies in the first reactor, and the distribution positions of the second fuel assemblies in the first reactor.

[0039] In step 102, a first contribution share of the first fuel assemblies to the fast neutron fluence at the neutron detector inside the irradiation monitoring tube is determined, and a second contribution share of the second fuel assemblies to the fast neutron fluence at the fluence peak position of the pressure vessel is determined.

[0040] The fast neutron refers to a neutron with relatively high energy and high movement speed in the reactor. The fast neutron fluence refers to the number of fast neutrons passing through a unit area per unit time. After determining the first fuel assemblies and the second fuel assemblies in the first reactor, the electronic device can further determine a first contribution share a of the first fuel assemblies to the fast neutron fluence at the neutron detector inside the irradiation monitoring tube.i and determining a second contribution share b of the second fuel assembly to the fast neutron fluence at the fluence peak location of the pressure vessel j The fluence peak location is the location through which the fast neutron peak fluence passes, which can be determined according to historical data. The fluence peak location is usually at a certain specific circumferential angle of the pressure vessel. The first contribution share is the ratio of the contribution of the first fuel assembly to the fast neutron fluence at the target point to the fast neutron fluence at the target point. The second contribution share is the ratio of the contribution of the second fuel assembly to the fast neutron fluence at the target point to the fast neutron fluence at the target point.

[0041] Exemplarily, according to the distribution position of the first fuel assembly in the first reactor and the predetermined contribution share of each fuel assembly in the first reactor, the electronic device can determine a first contribution share a of the first fuel assembly to the fast neutron fluence at the neutron detector in the irradiation surveillance tube i According to the distribution position of the second fuel assembly in the first reactor and the predetermined contribution share of each fuel assembly in the first reactor, the electronic device can determine a second contribution share b of the second fuel assembly to the fast neutron fluence at the fluence peak location of the pressure vessel j Alternatively, the first contribution share a i and the second contribution share b j may be determined by the Monte Carlo method or the conjugate transport method, respectively.

[0042] In step 103, a lead factor of the pressure vessel is determined according to the first relative power, the second relative power, the first contribution share and the second contribution share.

[0043] The lead factor represents the ratio of the fast neutron fluence at the neutron detector in the irradiation surveillance tube to the maximum fast neutron fluence at the inner surface and the quarter thickness of the pressure vessel. The fast neutron fluence is proportional to the relative power of the fuel assembly. Based on the foregoing characteristics, after obtaining the first relative power, the second relative power, the first contribution share and the second contribution share, the electronic device can determine the lead factor of the pressure vessel according to the first relative power, the second relative power, the first contribution share and the second contribution share.

[0044] The steps 101 to 103 shown in the embodiments of the present application obtain a first relative power of a first fuel assembly in a first reactor and a second relative power of a second fuel assembly in the first reactor, and determine a first contribution share of the first fuel assembly to a fast neutron fluence at a neutron detector in an irradiation monitoring tube, and a second contribution share of the second fuel assembly to a fast neutron fluence at a peak fluence position of a pressure vessel, and then determine an advance factor of the pressure vessel according to the first relative power, the second relative power, the first contribution share and the second contribution share. Through the foregoing steps, the advance factor of the pressure vessel in the first reactor can be simply and quickly determined according to the first relative power, the second relative power, the first contribution share and the second contribution share of the first reactor, and the calculation cost of the advance factor is reduced.

[0045] In addition, the advance factor can be used as a basis for determining a tube lifting time of the irradiation monitoring tube. Therefore, the method for determining the advance factor of the pressure vessel of the nuclear reactor provided in the embodiments of the present application can improve the efficiency of determining the tube lifting time of the irradiation monitoring tube by reducing the calculation cost of the advance factor.

[0046] In an embodiment of the present application, the determination of the first contribution share of the first fuel assembly to the fast neutron fluence at the neutron detector in the irradiation monitoring tube and the determination of the second contribution share of the second fuel assembly to the fast neutron fluence at the peak fluence position of the pressure vessel include:

[0047] Obtaining a composition feature of the first reactor, the composition feature being used to indicate a type and a structure of the first reactor;

[0048] Matching the composition feature of the first reactor with a plurality of composition features in a preset corresponding relationship to obtain contribution share information corresponding to the composition feature of the first reactor, the corresponding relationship including a plurality of composition features and contribution share information corresponding to each composition feature, each composition feature in the corresponding relationship being determined according to a second reactor, and the contribution share information corresponding to the composition feature in the corresponding relationship being used to describe contribution shares of fuel assemblies included in the corresponding second reactor;

[0049] Determining the first contribution share based on the contribution share information corresponding to the composition feature of the first reactor and a distribution position of the first fuel assembly in the first reactor;

[0050] Determining the second contribution share based on the contribution share information corresponding to the composition feature of the first reactor and a distribution position of the second fuel assembly in the first reactor.

[0051] Firstly, the electronic device can obtain the composition features of the first reactor, i.e., the reactor type and the reactor structure of the first reactor. The reactor type mainly refers to different types classified according to factors such as fuel form, coolant type, neutron energy distribution, and special design requirements, for example, pressurized water reactor, boiling water reactor, high-temperature gas-cooled reactor, fast neutron reactor, etc. The reactor structure is the composition and layout inside the reactor. In the embodiments of the present application, the reactor type of the first reactor is a pressurized water reactor. It can be understood that for multiple reactors of the same reactor type, the fuel assemblies selected are usually the same. And for multiple reactors of the same reactor structure, the layout and arrangement of the fuel assemblies are consistent. It can be seen that for multiple reactors of the same reactor type and the same reactor structure, the contribution shares of the fuel assemblies in the multiple reactors at the same distribution position to the fast neutron flux at the target point are the same. For example, for reactor 1 and reactor 2 of the same reactor type and the same reactor structure, assuming that fuel assembly 1 in reactor 1 and fuel assembly 2 in reactor 2 are at the same distribution position, the contribution shares of fuel assembly 1 and fuel assembly 2 to the fast neutron flux at the target point are the same.

[0052] Therefore, to improve the efficiency of subsequent determination of the first contribution share and the second contribution share, the electronic device can previously determine multiple second reactors to obtain a correspondence relationship including the composition features of the multiple second reactors and the contribution share information corresponding to each composition feature. Each composition feature in the correspondence relationship is determined according to a second reactor. The contribution share information corresponding to the composition features in the correspondence relationship is used to indicate the respective contribution shares of the multiple fuel assemblies in each second reactor. The second reactor refers to a reactor used to determine the correspondence relationship between the composition features and the contribution share information before the calculation of the lead factor.

[0053] In this way, in the actual application process of the nuclear reactor pressure vessel lead factor determination method, the composition features of the first reactor can be matched with the multiple composition features in the correspondence relationship to obtain the contribution share information corresponding to the composition features of the first reactor, and then the distribution position of the first fuel assembly in the first reactor and the distribution position of the second fuel assembly in the first reactor are respectively determined based on the composition features of the first reactor. Among them, the contribution share information corresponding to the composition features of the first reactor is used to describe the respective contribution shares of the multiple fuel assemblies in the first reactor. Subsequently, the first contribution share corresponding to the first fuel assembly can be determined according to the distribution position of the first fuel assembly in the first reactor and the contribution share information corresponding to the composition features of the first reactor, and the second contribution share corresponding to the second fuel assembly can be determined according to the distribution position of the second fuel assembly in the first reactor and the contribution share information corresponding to the composition features of the first reactor. In this way, the first contribution share and the second contribution share can be determined, which facilitates the subsequent calculation of the lead factor.

[0054] In an embodiment of the present application, the correspondence is obtained according to the following process:

[0055] For each of the second reactors, obtain a composition feature of the second reactor, the composition feature of the second reactor being used to indicate a type of the reactor and a structure of the reactor;

[0056] Based on the composition feature of the second reactor, determine a contribution share of each fuel assembly in the second reactor to a fast neutron fluence at a target point, the target point being at a neutron detector in an irradiation surveillance tube or a fluence peak position of a pressure vessel, the contribution share information corresponding to the composition feature of the second reactor including the contribution share of each fuel assembly in the second reactor;

[0057] According to the composition feature of each of the second reactors and the contribution share information corresponding to the composition feature of each of the second reactors, construct the correspondence.

[0058] To improve the efficiency of subsequently determining the first contribution share and the second contribution share, the electronic device can previously determine a plurality of second reactors to obtain a correspondence including the composition features of the plurality of second reactors and the contribution share information corresponding to each composition feature. Specifically, for each second reactor, a composition feature of the second reactor can be obtained. The composition feature of the second reactor is used to indicate a type of the reactor (for example, a pressurized water reactor) and a structure of the reactor (such as arrangement and layout of a plurality of fuel assemblies). Then, based on the composition feature of the second reactor, the electronic device can determine the contribution share corresponding to each fuel assembly in the second reactor, and further obtain the contribution share information corresponding to the composition feature of the second reactor according to the contribution share corresponding to each fuel assembly in the second reactor. In this way, according to the composition feature of each of the second reactors and the contribution share information corresponding to the composition feature of each of the second reactors, the correspondence can be constructed.

[0059] In an embodiment of the present application, the determining, based on the composition feature of the second reactor, of the contribution share of each fuel assembly in the second reactor to the fast neutron fluence at the target point includes:

[0060] Based on the composition feature of the second reactor, simulate a motion trajectory of each fast neutron emitted by each fuel assembly in the second reactor to obtain a plurality of transport trajectories, the transport trajectory being used to indicate a trajectory of each fast neutron from the fuel assembly in the second reactor to the target point;

[0061] According to the plurality of transport trajectories, determine the contribution amount of each fuel assembly in the second reactor to the fast neutron fluence at the target point;

[0062] determine a first ratio between a contribution of each fuel assembly in the second reactor and a fast neutron fluence at the target point, respectively;

[0063] determine the first ratio as a contribution share of the corresponding fuel assembly, to obtain the contribution share of each fuel assembly in the second reactor.

[0064] In constructing the correspondence relationship, the electronic device can first determine the contribution share of each fuel assembly in the second reactor. Specifically, the composition features of the second reactor include the type of the reactor (for example, a pressurized water reactor) and the structure of the reactor (including the position of the irradiation supervision tube, the position of the pressure vessel, the arrangement and layout of the plurality of fuel assemblies, etc.). Based on the composition features of the second reactor, the electronic device can use the Monte Carlo method to simulate the forward fast neutron transport process. That is, based on the composition features of the second reactor, the electronic device can determine the initial state of the fast neutron (such as position, energy, direction, etc.) and the physical properties of the medium (such as density, scattering cross section, absorption cross section, etc.).

[0065] Assuming that each fuel assembly in the second reactor uniformly emits fast neutrons, based on the initial state of the fast neutron and the physical properties of the medium, the electronic device can simulate the motion trajectory of each fast neutron emitted by each fuel assembly in the second reactor using the Monte Carlo method, to obtain a plurality of transport trajectories, i.e., trajectories indicating that each fast neutron is emitted from a fuel assembly in the second reactor to a target point. The target point is a neutron detector in the irradiation supervision tube, or a fluence peak position of the pressure vessel. Then, according to each transport trajectory, the electronic device can determine the starting point (i.e., a certain fuel assembly in the second reactor) and the ending point (i.e., the target point) of each fast neutron, and further determine which fuel assembly in the second reactor the fast neutron received at the target point originates from, so that the contribution of each fuel assembly in the second reactor to the fast neutron fluence at the target point, i.e., the number of fast neutrons emitted by each fuel assembly in the second reactor to the target point, can be determined. Subsequently, the electronic device can determine a first ratio between the contribution of each fuel assembly in the second reactor and the fast neutron fluence at the target point, respectively, and determine the first ratio as the contribution share of the corresponding fuel assembly. Through the foregoing manner, the electronic device can obtain the contribution share of each fuel assembly in the second reactor, and further obtain the contribution share information corresponding to the composition features of the second reactor, so that the correspondence relationship is constructed.

[0066] In an embodiment of the present application, the determination of the contribution share of each fuel assembly in the second reactor to the fast neutron fluence at the target point based on the composition features of the second reactor comprises:

[0067] determine, based on the composition characteristics of the second reactor, a response value of each fuel assembly in the second reactor to the target point;

[0068] determine, based on the response value of each fuel assembly in the second reactor to the target point, a sum of response values of a plurality of fuel assemblies in the second reactor to the target point;

[0069] respectively determine a second ratio of the response value of each fuel assembly in the second reactor to the target point and the sum of response values of the plurality of fuel assemblies in the second reactor to the target point;

[0070] determine the second ratio as a contribution share of the corresponding fuel assembly, to obtain the contribution share of each fuel assembly in the second reactor.

[0071] In constructing the correspondence relationship, the electronic device can first determine the contribution share of each fuel assembly in the second reactor. The composition characteristics of the second reactor include the type of the second reactor (for example, a pressurized water reactor) and the structure of the reactor (including the position of the irradiation supervision tube, the position of the pressure vessel, the arrangement and layout of the plurality of fuel assemblies, etc.). Based on the composition characteristics of the second reactor, the electronic device can perform the operation of the reverse fast neutron transport process by using the conjugate transport method. That is, according to the composition characteristics of the second reactor, the electronic device can determine the initial state (for example, position, energy, direction, etc.) of the fast neutron and the physical properties (for example, density, scattering cross section, absorption cross section, etc.) of the medium. The target point is a neutron detector in the irradiation supervision tube or a fluence peak position of the pressure vessel. Assuming that the fast neutron is emitted from the target point, based on the initial state of the fast neutron and the physical properties of the medium, the electronic device can obtain the response value of each fuel assembly in the second reactor to the target point by using the conjugate transport method for one operation, and then obtain the sum of response values of the plurality of fuel assemblies in the second reactor to the target point according to the response value of each fuel assembly in the second reactor to the target point. In this way, the electronic device can respectively determine the second ratio of the response value of each fuel assembly in the second reactor to the target point and the sum of response values of the plurality of fuel assemblies in the second reactor to the target point, and determine the second ratio as the contribution share of the corresponding fuel assembly, to obtain the contribution share of each fuel assembly in the second reactor. Through the foregoing manner, the electronic device can obtain the contribution share of each fuel assembly in the second reactor, and then obtain the contribution share information corresponding to the composition characteristics of the second reactor, so that the correspondence relationship is constructed.

[0072] In an embodiment of the present application, the determining, according to the first relative power, the second relative power, the first contribution share and the second contribution share, of the lead factor of the pressure vessel comprises:

[0073] multiplying the first relative power and the first contribution share, to obtain a first product;

[0074] multiplying the second relative power and the second contribution share, to obtain a second product;

[0075] taking a ratio of the first product and the second product as a third ratio;

[0076] multiplying the third ratio, a preset correction factor, and a preset proportionality factor, to obtain an advance factor of the pressure vessel.

[0077] According to the first relative power, the second relative power, the first contribution share, and the second contribution share, the electronic device can quickly determine the advance factor of the pressure vessel. Specifically, the electronic device can multiply the first relative power and the first contribution share to obtain a first product, and multiply the second relative power and the second contribution share to obtain a second product. The electronic device can determine a ratio of the first product and the second product, and take the ratio as a third ratio. Then, the electronic device can multiply the third ratio, a preset correction factor, and a preset proportionality factor, to obtain the advance factor of the pressure vessel. The correction factor can be determined according to the leakage degree of neutrons in the core and the axial distribution of neutrons. The proportionality factor is a constant, which can be obtained according to the type of the first reactor.

[0078] In the case that the first fuel assembly includes a plurality of fuel assemblies (for example, fuel assembly 1 and fuel assembly 2), and the second fuel assembly includes a plurality of fuel assemblies (for example, fuel assembly 3 and fuel assembly 4), the first relative power P i1 and the first contribution share a i1 of the fuel assembly 1 are multiplied to obtain a first product corresponding to the fuel assembly 1. The first relative power P i2 and the first contribution share a i2 of the fuel assembly 2 are multiplied to obtain a first product corresponding to the fuel assembly 2. Then, the first product corresponding to the fuel assembly 1 and the first product corresponding to the fuel assembly 2 can be added to obtain a sum of the first products. Similarly, the second relative power P j3 and the second contribution share b j3 of the fuel assembly 3 are multiplied to obtain a second product corresponding to the fuel assembly 3. The second relative power P j4 and the second contribution share b j4The first product and the second product corresponding to the fuel assembly 4 are multiplied to obtain a second product corresponding to the fuel assembly 4. Then, the second product corresponding to the fuel assembly 3 and the second product corresponding to the fuel assembly 4 can be added to obtain a sum of the second products. Then, a ratio of the sum of the first products to the sum of the second products is determined, and the ratio is taken as a third ratio. Thus, the lead factor of the pressure vessel can be obtained according to the third ratio, the correction factor and the proportional factor.

[0079] The calculation process of the lead factor of the pressure vessel can satisfy the following formula:

[0080]

[0081] wherein, L f is the lead factor of the pressure vessel, k is the proportional factor, ξ is the correction factor, a i is the first contribution share of the i th fuel assembly, P i is the first relative power of the i th fuel assembly, b j is the second contribution share of the j th fuel assembly, P j is the second relative power of the j th fuel assembly, m is the number of the first fuel assemblies, and n is the number of the second fuel assemblies.

[0082] Thus, by introducing the correction factor, the deviation caused by the leakage degree of neutrons in the core and the difference in axial distribution of neutrons can be corrected, and the accuracy of the obtained lead factor is higher.

[0083] Figure 2 is another flowchart of the method for determining the lead factor of the nuclear reactor pressure vessel provided in the embodiments of the present application. Please refer to Figure 2 The method for determining the lead factor of the nuclear reactor pressure vessel provided in the embodiments of the present application is exemplified as follows. The method for determining the lead factor of the nuclear reactor pressure vessel comprises the following steps.

[0084] In step 201, the radial power distribution of the core of the first reactor is obtained.

[0085] In step 202, the proportional factor is determined according to the reference data of the same type of unit having the same reactor structure as the first reactor, and the correction factor is determined according to the leakage of neutrons and the axial distribution of neutrons in the core of the same type of unit.

[0086] In step 203, the first contribution share of m groups of fuel assemblies near the neutron detector in the irradiation supervision tube is determined.

[0087] In step 204, the second contribution share of n groups of fuel assemblies near the position of the fluence peak of the inner wall of the pressure vessel is determined.

[0088] In step 205, according to the radial power distribution, a first relative power of m groups of fuel assemblies near the neutron detector in the irradiation monitoring tube is determined, and a second relative power of n groups of fuel assemblies near the fluence peak position of the inner wall of the pressure vessel is determined.

[0089] In step 206, according to the scaling factor, the correction factor, the first contribution share, the second contribution share, the first relative power and the second relative power, the lead factor of the pressure vessel is determined.

[0090] The electronic device can select m groups of fuel assemblies near the irradiation monitoring tube, and select n groups of fuel assemblies near the circumferential direction of the fluence peak position of the pressure vessel. Then, the first contribution share a of the selected m groups of fuel assemblies to the fast neutron fluence at the neutron detector in the irradiation monitoring tube can be determined i , and the first relative power P i of the m groups of fuel assemblies is obtained, i = 1,..., m. At the same time, the second contribution share b of the selected n groups of fuel assemblies to the fluence peak position of the inner wall of the pressure vessel can be determined j , and the second relative power P j of the n groups of fuel assemblies is obtained, j = 1,..., n. Then, according to formula (1), the lead factor of the pressure vessel can be obtained.

[0091] The comparison between the 10 groups of lead factor calculation results obtained by the foregoing nuclear reactor pressure vessel lead factor determination method and the reference results can be seen from the following table 1.

[0092] Table 1

[0093] Serial number Reference result Lead factor calculation result Relative deviation 1 2.51 2.55 1.55％ 2 3.06 2.94 -3.86％ 3 3.21 3.08 -3.82％ 4 3.06 2.94 -3.97％ 5 2.65 2.53 -4.72％ 6 3.19 3.06 -4.05％ 7 3.34 3.28 -1.72％ 8 2.73 2.66 -2.68％ 9 3.42 3.45 0.87％ 10 3.83 3.73 -2.81％

[0094] From the table, it can be seen that the relative deviation of the 10 groups of lead factor calculation results and the reference results is within ±10%, and the relative deviation is small, so the accuracy of the lead factor obtained by the nuclear reactor pressure vessel lead factor determination method of the embodiment of the present application is high.

[0095] Figure 3 is a structural schematic diagram of the nuclear reactor pressure vessel lead factor determination device provided by the embodiment of the present application, please refer to Figure 3 The embodiment of the present application also provides a nuclear reactor pressure vessel lead factor determination device 300, which can realize the above-mentioned nuclear reactor pressure vessel lead factor determination method, and the device 300 comprises:

[0096] The power acquisition module 301 is configured to acquire a first relative power of a first fuel assembly in a first reactor and a second relative power of a second fuel assembly in the first reactor, the first fuel assembly being a fuel assembly with a distance to an irradiation supervision tube less than a first preset value, and the second fuel assembly being a fuel assembly with a distance to a pressure vessel less than a second preset value;

[0097] The share determination module 302 is configured to determine a first contribution share of the first fuel assembly to a fast neutron fluence at a neutron detector in the irradiation supervision tube and determine a second contribution share of the second fuel assembly to a fast neutron fluence at a peak position of the pressure vessel.

[0098] The lead factor determination module 303 is configured to determine a lead factor of the pressure vessel according to the first relative power, the second relative power, the first contribution share, and the second contribution share.

[0099] The specific implementation of the nuclear reactor pressure vessel lead factor determination apparatus is basically the same as that of the nuclear reactor pressure vessel lead factor determination method, and will not be repeated here.

[0100] The embodiment of the present application further provides an electronic device, which comprises a memory and a processor, the memory stores a computer program, and the processor executes the computer program to realize the nuclear reactor pressure vessel lead factor determination method. The electronic device can be any intelligent terminal including a tablet computer, a vehicle-mounted computer, etc.

[0101] Figure 4 is a hardware structure schematic diagram of the electronic device provided by the embodiment of the present application, please refer to Figure 4 . The electronic device comprises:

[0102] The processor 401 can be implemented in a general-purpose CPU (Central Processing Unit, central processor), a microprocessor, an application specific integrated circuit (ASIC), or one or more integrated circuits, etc., and is used to execute related programs to realize the technical solutions provided by the embodiment of the present application.

[0103] The memory 402 can be implemented in the form of a Read-Only Memory (ROM), a static storage device, a dynamic storage device, or a Random Access Memory (RAM), etc. The memory 402 can store an operating system and other application programs. When the technical solutions provided by the embodiments of the present specification are implemented by software or firmware, the related program codes are stored in the memory 402 and are called and executed by the processor 401 to perform the nuclear reactor pressure vessel lead factor determination method of the embodiments of the present application;

[0104] The input / output interface 403 is configured to realize information input and output.

[0105] The communication interface 404 is configured to realize the communication interaction between the device and other devices. The communication can be realized by a wired manner (for example, a USB, a network cable, etc.) or a wireless manner (for example, a mobile network, WIFI, Bluetooth, etc.).

[0106] The bus 405 is configured to transmit information between various components (for example, the processor 401, the memory 402, the input / output interface 403, and the communication interface 404) of the device.

[0107] The processor 401, the memory 402, the input / output interface 403, and the communication interface 404 are connected to each other through the bus 405 to realize the communication connection between the device.

[0108] The embodiments of the present application also provide a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the nuclear reactor pressure vessel lead factor determination method.

[0109] The memory is a non-transitory computer readable storage medium, which can be used to store a non-transitory software program and a non-transitory computer executable program. In addition, the memory can include a high-speed random access memory and can also include a non-transitory memory, such as at least one magnetic disk storage device, a flash memory device, or other non-transitory solid-state memory device. In some embodiments, the memory can optionally include a memory remotely arranged relative to the processor. These remote memories can be connected to the processor through a network. Examples of the above network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0110] In addition, the embodiments of the present application can be implemented by a computer program product. The instructions in the computer program product are executed by the processor of an electronic device to enable the electronic device to implement any of the nuclear reactor pressure vessel lead factor determination methods in the above embodiments.

[0111] The method and device for determining a lead factor of a nuclear reactor pressure vessel provided in the application obtain a first relative power of a first fuel assembly in a first reactor and a second relative power of a second fuel assembly in the first reactor, determine a first contribution share of the first fuel assembly to a fast neutron flux at a neutron detector in an irradiation monitoring tube, and determine a second contribution share of the second fuel assembly to a fast neutron flux at a peak flux position of the pressure vessel, and then determine the lead factor of the pressure vessel according to the first relative power, the second relative power, the first contribution share and the second contribution share. Through the foregoing steps, the lead factor of the pressure vessel in the first reactor can be simply and quickly determined according to the first relative power, the second relative power, the first contribution share and the second contribution share of the first reactor, and the calculation cost of the lead factor is reduced.

[0112] The embodiments described in the embodiments of the application are used to more clearly illustrate the technical solutions of the embodiments of the application, and do not constitute a limitation on the technical solutions provided by the embodiments of the application. It can be understood by those skilled in the art that, with the evolution of technology and the appearance of new application scenarios, the technical solutions provided by the embodiments of the application are also applicable to similar technical problems.

[0113] It can be understood by those skilled in the art that the technical solutions shown in the figures do not constitute a limitation on the embodiments of the application, and can include more or fewer steps than those shown in the figures, or combine certain steps or different steps.

[0114] The device embodiments described above are merely schematic, wherein the units described as separate components can or can not be physically separated, that is, can be located in one place, or can be distributed on multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the embodiments of the application.

[0115] It can be understood by those skilled in the art that all or some steps in the method disclosed above, the function modules / units in the system and the device can be implemented as software, firmware, hardware and appropriate combinations thereof.

[0116] The terms "first", "second", "third", "fourth", and the like in the description and in the claims of this application, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the use of the terms so termed is interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of orderly or chronological mundane operation, reverse order operation, based on circuitry availability, based on stated preference or the like, and that "default" or other orderings are thus permissible. Further, the terms "comprise", "comprising", "include", "including", and the like, are specifically intended to be open-ended. That is, references to individual steps and the like do not suhstantially exclude the presence of two or more of a given step or its integral presence in the process, method, system, article, or apparatus having been made with a wider scope. The use of notation such as "first", "second", "third", etc. does not generally limit the areas, but can be used for clarity, and merely establishes the order unless otherwise stated below.

[0117] It should be understood that, in the application, "at least one" means one or more, and "multiple" means two or more. "And / or" is used to describe the relationship between associated objects, which means that there can be three relationships, for example, "A and / or B" can mean that there are only A, only B, and A and B at the same time, where A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects. "At least one of the following" or the like means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b or c can mean a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0118] In several embodiments provided in the application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the above units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be omitted or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed objects can be indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0119] The units described above as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e. they can be located in one place or distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0120] In addition, each function unit in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software function unit.

[0121] If the integrated unit is realized in the form of a software function unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application, essentially or in part, or all or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes multiple instructions used to cause a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods in the embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various other media that can store programs.

[0122] The preferred embodiments of the embodiments of the present application are described above with reference to the accompanying drawings, and are not intended to limit the scope of the embodiments of the present application. Any modifications, equivalent replacements and improvements made by those skilled in the art without departing from the scope and essence of the embodiments of the present application shall be within the scope of the embodiments of the present application.

Claims

1. A method for determining a lead factor for a nuclear reactor pressure vessel, the method comprising: The method comprises: obtaining a first relative power of a first fuel assembly in a first reactor and a second relative power of a second fuel assembly in the first reactor, the first fuel assembly being a fuel assembly with a distance to an irradiation supervision tube less than a first preset value, and the second fuel assembly being a fuel assembly with a distance to a pressure vessel less than a second preset value; determining a first contribution share of the first fuel assembly to a fast neutron fluence at a neutron detector in the irradiation supervision tube and a second contribution share of the second fuel assembly to a fast neutron fluence at a fluence peak position of the pressure vessel; determining an advance factor of the pressure vessel according to the first relative power, the second relative power, the first contribution share and the second contribution share; wherein the determining of the advance factor of the pressure vessel according to the first relative power, the second relative power, the first contribution share and the second contribution share comprises: multiplying the first relative power by the first contribution share to obtain a first product; multiplying the second relative power by the second contribution share to obtain a second product; taking a ratio of the first product to the second product as a third ratio; multiplying the third ratio, a preset correction factor and a preset proportionality factor to obtain the advance factor of the pressure vessel.

2. The method of claim 1, wherein, The determining of the first contribution share of the first fuel assembly to the fast neutron fluence at the neutron detector in the irradiation supervision tube and the second contribution share of the second fuel assembly to the fast neutron fluence at the fluence peak position of the pressure vessel comprises: obtaining a composition feature of the first reactor, the composition feature being used to indicate a type and a structure of the first reactor; matching the composition feature of the first reactor with a plurality of composition features in a preset corresponding relationship to obtain contribution share information corresponding to the composition feature of the first reactor, the corresponding relationship comprising a plurality of composition features and contribution share information corresponding to each composition feature, each composition feature in the corresponding relationship being determined according to a second reactor, and the contribution share information corresponding to the composition feature in the corresponding relationship being used to describe contribution shares of fuel assemblies included in the corresponding second reactor; determining the first contribution share based on the contribution share information corresponding to the composition feature of the first reactor and a distribution position of the first fuel assembly in the first reactor; determining the second contribution share based on the contribution share information corresponding to the composition feature of the first reactor and a distribution position of the second fuel assembly in the first reactor.

3. The method of claim 2, wherein, The corresponding relationship is obtained according to the following process: for each second reactor, obtaining a composition feature of the second reactor, the composition feature of the second reactor being used to indicate a type and a structure of the second reactor; determine, based on the composition feature of the second reactor, a contribution share of each fuel assembly in the second reactor to a fast neutron fluence at a target point, the target point being at a neutron detector inside an irradiation monitoring tube or a fluence peak position of a pressure vessel, the contribution share information corresponding to the composition feature of the second reactor including the contribution share of each fuel assembly in the second reactor; construct the correspondence according to the composition feature of each second reactor and the contribution share information corresponding to the composition feature of each second reactor.

4. The method of claim 3, wherein, The determining, based on the composition feature of the second reactor, of the contribution share of each fuel assembly in the second reactor to a fast neutron fluence at a target point includes: simulate, based on the composition feature of the second reactor, a motion trajectory of each fast neutron emitted by each fuel assembly in the second reactor to obtain a plurality of transport trajectories, the transport trajectory being used to indicate a trajectory of each fast neutron from the fuel assembly in the second reactor to the target point; determine, according to the plurality of transport trajectories, a contribution amount of each fuel assembly in the second reactor to the fast neutron fluence at the target point; respectively determine a first ratio between the contribution amount of each fuel assembly in the second reactor and the fast neutron fluence at the target point; determine the first ratio as the contribution share of the corresponding fuel assembly to obtain the contribution share of each fuel assembly in the second reactor.

5. The method of claim 3, wherein, The determining, based on the composition feature of the second reactor, of the contribution share of each fuel assembly in the second reactor to a fast neutron fluence at a target point includes: determine, based on the composition feature of the second reactor, a response value of each fuel assembly in the second reactor to the target point, taking the target point as a neutron source emitting fast neutrons; determine, according to the response value of each fuel assembly in the second reactor to the target point, a sum of the response values of the plurality of fuel assemblies in the second reactor to the target point; respectively determine a second ratio between the response value of each fuel assembly in the second reactor to the target point and the sum of the response values of the plurality of fuel assemblies in the second reactor to the target point; determine the second ratio as the contribution share of the corresponding fuel assembly to obtain the contribution share of each fuel assembly in the second reactor.

6. A nuclear reactor pressure vessel lead factor determination apparatus characterized by, The device includes: a power acquisition module configured to acquire a first relative power of a first fuel assembly in a first reactor and a second relative power of a second fuel assembly in the first reactor, the first fuel assembly being a fuel assembly with a distance to an irradiation monitoring tube less than a first preset value, and the second fuel assembly being a fuel assembly with a distance to a pressure vessel less than a second preset value; a share determination module configured to determine a first contribution share of the first fuel assembly to a fast neutron fluence at a neutron detector inside the irradiation monitoring tube and a second contribution share of the second fuel assembly to a fast neutron fluence at a fluence peak position of the pressure vessel; and a correspondence construction module configured to construct a correspondence between the first contribution share and the second contribution share. The superposition factor determination module is configured to determine a superposition factor of the pressure container according to the first relative power, the second relative power, the first contribution share and the second contribution share. The superposition factor determination module is further configured to: multiply the first relative power by the first contribution share to obtain a first product; multiply the second relative power by the second contribution share to obtain a second product; obtain a third ratio value by taking a ratio of the first product to the second product; multiply the third ratio value, a preset correction factor and a preset proportional factor to obtain the superposition factor of the pressure container.

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