A method and system for correcting neutron leakage in a pebble bed core of a pebble bed high temperature gas cooled reactor

Abstract

The application discloses a kind of ball bed type high temperature gas cooled reactor ball bed reactor core neutron leakage correction method and system, it is related to nuclear reactor physics calculation technical field, including using assembly calculation program to obtain the multi-group and few-group homogenization cross section of all assemblies of ball bed type high temperature gas cooled reactor;The multi-group homogenization cross section of average ball in all different mixing ratio ball bed area and the few-group homogenization cross section of all ball bed area are calculated;Obtain the few-group neutron flux and few-group neutron leakage rate of each area of whole reactor;Get the multi-group neutron leakage spectrum of average ball, update the few-group homogenization cross section of each batch ball in ball bed area;The few-group homogenization cross section of ball bed area is calculated, and three-dimensional whole reactor diffusion calculation and neutron leakage correction are carried out, if the few-group homogenization cross section of all ball bed area converges, complete the neutron leakage correction of ball bed reactor core area.The neutron leakage effect of ball bed reactor core is effectively corrected, and the precision of ball bed type high temperature gas cooled reactor core calculation is improved.

Description

Technical Field

[0001] This invention relates to the field of nuclear reactor physics calculation technology, and in particular to a method and system for correcting neutron leakage in the core of a pebble bed type high-temperature gas-cooled reactor. Background Technology

[0002] The pebble bed high-temperature gas-cooled reactor has a slender geometry, resulting in a strong neutron leakage effect in the radial direction. Furthermore, neutron leakage between materials is not considered in the assembly calculations for the spherical elements. Therefore, the homogenized cross-section of the spherical elements obtained from the assembly calculations does not account for the neutron leakage effect, and the homogenized cross-section of the pebble bed core region calculated based on the homogenized cross-section of the spherical elements also does not account for the neutron leakage effect. This will introduce significant calculation errors into the whole-reactor diffusion calculations, thus necessitating correction for the neutron leakage effect in the pebble bed core.

[0003] Neutron leakage correction requires solving a multi-group neutron moderation equation that reflects the true neutron leakage situation in the pebble bed region. Whole-reactor diffusion calculations can provide the few-group neutron leakage rate in the pebble bed region. However, the pebble bed region contains different batches of spheres, and the neutron leakage rate of the pebble bed region alone cannot reflect the neutron leakage situation of each batch of spheres. Since the pebble bed gap is filled with helium, which is almost transparent to neutrons, the neutrons in the pebble bed region originate from the various batches of spheres within it. Therefore, neutrons leaking from the pebble bed region must originate from the various batches of spheres within it. Existing techniques solve the multi-group neutron moderation equation for the entire pebble bed region to obtain the multi-group neutron leakage energy spectrum of the pebble bed region. This assumes that the neutrons leaking from the pebble bed region originate from all regions within the pebble bed region, including the helium region. Using this neutron leakage energy spectrum to merge and update the few-group homogenization cross section of each batch of spheres inevitably introduces a large error.

[0004] The purpose of this invention is to provide a method for correcting neutron leakage in the core of a pebble bed type high-temperature gas-cooled reactor, which effectively improves the accuracy of core calculations for the pebble bed type high-temperature gas-cooled reactor. Summary of the Invention

[0005] In view of the above-mentioned problems, the present invention is proposed.

[0006] Therefore, the problem to be solved by this invention is: how to improve the accuracy of core calculations for pebble bed type high-temperature gas-cooled reactors.

[0007] To address the aforementioned technical problems, this invention provides the following technical solution: a method for correcting neutron leakage in the core of a pebble bed high-temperature gas-cooled reactor, comprising: calculating the multi-group and few-group homogenization cross sections of all components of the pebble bed high-temperature gas-cooled reactor using a component calculation program; calculating the multi-group homogenization cross section of the average sphere in all pebble bed regions with different mixing ratios and the few-group homogenization cross section of all pebble bed regions; obtaining the few-group neutron flux and few-group neutron leakage rate in each region of the entire reactor; solving the multi-group neutron slowing equation for the average sphere in all pebble bed regions to obtain the multi-group neutron leakage energy spectrum of the average sphere, and updating the few-group homogenization cross section of each batch of spheres in the pebble bed region; calculating the few-group homogenization cross section of the pebble bed region, performing three-dimensional whole-reactor diffusion calculation and neutron leakage correction; and completing the neutron leakage correction of the pebble bed core region if the few-group homogenization cross sections of all pebble bed regions converge.

[0008] As a preferred embodiment of the pebble bed type high-temperature gas-cooled reactor core neutron leakage correction method described in this invention, wherein: the multi-group homogenization cross section of the average spheres in the pebble bed region includes, using the multi-group homogenization cross section of fuel spheres and graphite spheres, and based on the collision probability method, solving for the multi-group neutron flux of fuel spheres and graphite spheres, and calculating the multi-group homogenization cross section of the average spheres in the pebble bed region as follows:

[0009] χ ave,h =f fpeb χ fpeb,h +f gpeb χ gpeb,h

[0010]

[0011]

[0012] Among them, f fpeb f represents the volume fraction of the fuel spheres relative to all spheres in the sphere bed region. gpeb χ represents the volume fraction of graphite spheres in the total volume of all spheres in the sphere bed region. ave,h χ is the multi-group fission energy spectrum of the average sphere h-th energy group within the sphere bed region. fpeb,h For the multigroup fission energy spectrum of the h-th energy group of the fuel sphere, χ gpeb,h The multigroup fission energy spectrum of the h-th energy group of graphite spheres, Σ ave,x,h The macroscopic reaction cross section of the average spherical energy group h in the spherical bed region is given by φ, where x is the reaction type and φ is the macroscopic reaction cross section of the average spherical energy group h in the spherical bed region. fpeb,h Let φ be the multigroup neutron flux of the h-th energy group of the fuel sphere. gpeb,h Let Σ be the multigroup neutron flux of the h-th energy group of graphite spheres. fpeb,x,h For the multigroup macroscopic reaction cross section of the h-th energy group of the fuel sphere, Σ gpeb,x,h For the multigroup macroscopic reaction cross section of the h-th energy group of graphite spheres, Σ ave,s,h′→hΣ is the macroscopic scattering cross section of the average spherical neutron in the h′ energy group scattered to the h-th energy group within the spherical bed region. fpeb,s,h′→h Σ is the macroscopic scattering cross section of the fuel sphere neutrons in energy group h′ scattered to energy group h. gpeb,s,h′→h The multi-group macroscopic scattering cross section is the scattering cross section of neutrons from the h′ energy group of graphite spheres to the h energy group.

[0013] As a preferred embodiment of the pebble bed type high-temperature gas-cooled reactor neutron leakage correction method described in this invention, wherein: the minority group homogenization cross section of all pebble bed regions includes, using the minority group homogenization cross section of fuel spheres and graphite spheres, based on the collision probability method, solving for the minority group neutron flux of fuel spheres, graphite spheres and pebble bed voids, and calculating the minority group homogenization cross section of all pebble bed regions as follows:

[0014] χ pbed,g =ρ(f fpeb χ fpeb,h +f gpeb χ gpeb,h )

[0015]

[0016]

[0017] Where ρ is the filling rate of the balls in the ball bed area, and χ pbed,g The energy spectrum of the g-th energy group in the ball bed region is the few-group fission energy spectrum, χ fpeb,g χ is the few-group fission energy spectrum of the g-th energy group of the fuel sphere. gpeb,g The energy spectrum of the few-group fission of the g-th energy group of graphite spheres, Σ pbed,x,h φ is the macroscopic reaction cross section of the g-th energy group in the spherical bed region, representing a minority group. fpeb,g Let φ be the minority group neutron flux of the g-th energy group of the fuel sphere. gpeb,g Let φ be the minority group neutron flux of the g-th energy group of graphite spheres. 0,g Let Σ be the minority group neutron flux of the g-th energy group in the sphere bed void. fpeb,x,g Let Σ be the macroscopic reaction cross section of the minority group of the g-th energy group of the fuel sphere. gpeb,x,g Let Σ be the macroscopic reaction cross section of the minority group of the g-th energy group of graphite spheres. pbed,s,g′→g Σ is the macroscopic scattering cross section of the g′ energy group neutron scattered into the g energy group in the spherical bed region. fpeb,s,g′→g Σ is the minority group macroscopic scattering cross section of the neutrons from the g′ energy group of the fuel sphere to the g energy group. gpeb,s,g′→g This is the minority group macroscopic scattering cross section of the graphite spheres from the g′ energy group to the g energy group.

[0018] As a preferred embodiment of the pebble bed type high-temperature gas-cooled reactor neutron leakage correction method described in this invention, the minority group neutron flux and minority group neutron leakage rate of each region of the entire reactor are obtained by performing three-dimensional whole-reactor diffusion calculation using the minority group homogenization cross section of the pebble bed region.

[0019] As a preferred embodiment of the pebble bed type high-temperature gas-cooled reactor neutron leakage correction method described in this invention, the multi-group neutron leakage energy spectrum of the average sphere includes: calculating the multi-group leakage cross-section of the pebble bed region; using the multi-group homogenization cross-section of the average sphere in the pebble bed region, solving the multi-group neutron slowing equation to obtain the multi-group neutron leakage energy spectrum of the average sphere in the pebble bed region.

[0020]

[0021]

[0022] Where, Σ L,h For the multiple leakage sections in the ball bed region, Σ L,g For the small group leakage section in the ball bed region, L pbed,g Let g be the minority group neutron leakage rate of the g-th energy group in the sphere bed region. Let Σ be the minority group neutron flux of the g-th energy group in the sphere bed region. ave,t,h Let (νΣ) be the macroscopic total cross section of the average spherical energy group h in the spherical bed region. ave,f ) h′ For the multi-group macroscopic fission neutron generation cross section of the average spherical h′ energy group in the spherical bed region, k eff φ is the effective proliferation coefficient of the ball bed region. ave,h The energy spectrum of the multi-group neutron leakage of the average sphere within the sphere bed region.

[0023] As a preferred embodiment of the pebble bed type high-temperature gas-cooled reactor core neutron leakage correction method described in this invention, the minority group homogenization cross section of each batch of spheres in the updated pebble bed region includes, with the multi-group neutron leakage energy spectrum of the average sphere as the weight, the minority group homogenization cross section of the fuel spheres and graphite spheres in the updated pebble bed region is expressed as follows:

[0024]

[0025]

[0026]

[0027]

[0028] As a preferred embodiment of the pebble bed type high-temperature gas-cooled reactor neutron leakage correction method described in this invention, the neutron leakage correction of the pebble bed core region includes repeatedly performing the following operations: obtaining the minority group neutron flux and minority group neutron leakage rate of each region of the entire reactor, updating the minority group homogenization cross section of each batch of spheres in the pebble bed region, and performing three-dimensional whole-reactor diffusion calculation and neutron leakage correction operations until the minority group homogenization cross section of all pebble bed regions converges, thereby completing the neutron leakage correction of the pebble bed core region.

[0029] Another objective of this invention is to provide a neutron leakage correction system for the core of a pebble bed type high-temperature gas-cooled reactor, which solves the problem of effectively improving the accuracy of calculations for the core of a pebble bed type high-temperature gas-cooled reactor by constructing a correction system.

[0030] To address the aforementioned technical problems, this invention provides the following technical solution: a pebble bed type high-temperature gas-cooled reactor core neutron leakage correction system, comprising a data acquisition module, a model training module, a model verification module, a correction calculation module, and a result display module; the data acquisition module is used to collect relevant data of the pebble bed type high-temperature gas-cooled reactor, including multi-group and few-group homogenization cross sections of the components, multi-group and few-group homogenization cross sections of the pebble bed region, and few-group neutron flux and few-group neutron leakage rate in each region of the entire reactor; the model training module is used to train the correction model, and establishes a mathematical model for neutron leakage correction through model training based on data and algorithms; the model verification module is used to verify the accuracy and reliability of the trained correction model; the correction calculation module uses the trained correction model and the real-time acquired data to calculate neutron leakage correction, and performs real-time correction of neutron leakage in the pebble bed type high-temperature gas-cooled reactor according to the algorithm and logic of the correction model, and outputs the corrected result; the result display module is used to display and visualize the corrected neutron leakage result for user analysis and decision-making.

[0031] A computer device includes a memory and a processor, the memory storing a computer program, characterized in that the processor executes the computer program to implement the steps of the pebble bed type high-temperature gas-cooled reactor core neutron leakage correction method as described above.

[0032] A computer-readable storage medium storing a computer program thereon, characterized in that, when the computer program is executed by a processor, it implements the steps of the pebble bed type high-temperature gas-cooled reactor core neutron leakage correction method as described above.

[0033] The beneficial effects of this invention are as follows: The neutron leakage correction method for pebble bed cores of a pebble bed-type high-temperature gas-cooled reactor provided by this invention, based on the correction of the neutron leakage effect of the pebble bed core using a multi-group average spherical cross section, can significantly reduce calculation bias, effectively correct the neutron leakage effect of the pebble bed core, and improve the accuracy of pebble bed-type high-temperature gas-cooled reactor core calculations. By replacing the neutron leakage in the pebble bed region with the neutron leakage of the average sphere, the multi-group neutron leakage energy spectrum of the average sphere is obtained, allowing for more accurate updating of the few-group homogenization cross section of each batch of spheres within the calculated pebble bed region, and more effectively considering the neutron leakage effect in the pebble bed core region. Replacing the neutron leakage in the pebble bed region with the neutron leakage of the average sphere, and updating the few-group homogenization cross section of each batch of spheres based on the multi-group neutron leakage energy spectrum of the average sphere, effectively considers the neutron leakage effect in the pebble bed core region and is feasible. Attached Figure Description

[0034] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0035] Figure 1 The flowchart illustrates a method for correcting neutron leakage in the core of a pebble bed type high-temperature gas-cooled reactor, as provided in the first embodiment of the present invention.

[0036] Figure 2 The above is a general flowchart of a method for correcting neutron leakage in the core of a pebble bed type high-temperature gas-cooled reactor, which is provided in the first embodiment of the present invention.

[0037] Figure 3 This is a schematic cross-sectional view of a pebble bed core model with a 4.2% enrichment level and a 7:8 mixing ratio of fuel spheres and graphite spheres, as provided in the first embodiment of the present invention for a pebble bed type high-temperature gas-cooled reactor core neutron leakage correction method.

[0038] Figure 4 This is a schematic longitudinal section of a pebble bed core model with a 4.2% enrichment level and a 7:8 mixing ratio of fuel spheres and graphite spheres, which is part of a pebble bed type high-temperature gas-cooled reactor core neutron leakage correction method provided in the first embodiment of the present invention.

[0039] Figure 5 This is a structural diagram of a pebble bed type high-temperature gas-cooled reactor core neutron leakage correction system provided for the second embodiment of the present invention. Detailed Implementation

[0040] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0041] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0042] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0043] Example 1

[0044] Reference Figures 1-4 This is the first embodiment of the present invention, which provides a method for correcting neutron leakage in the core of a pebble bed high-temperature gas-cooled reactor. The method includes: calculating the multi-group and few-group homogenization cross sections of all components of the pebble bed high-temperature gas-cooled reactor using a component calculation program; calculating the multi-group homogenization cross section of the average sphere in all pebble bed regions with different mixing ratios and the few-group homogenization cross section of all pebble bed regions; obtaining the few-group neutron flux and few-group neutron leakage rate in each region of the entire reactor; solving the multi-group neutron slowing equation for the average sphere in all pebble bed regions to obtain the multi-group neutron leakage energy spectrum of the average sphere, and updating the few-group homogenization cross section of each batch of spheres in the pebble bed region; calculating the few-group homogenization cross section of the pebble bed region, performing three-dimensional whole-reactor diffusion calculations and neutron leakage correction; and completing the neutron leakage correction for the pebble bed core region if the few-group homogenization cross sections of all pebble bed regions converge.

[0045] like Figure 2As shown, the component calculation program is used to calculate the multi-group and few-group homogenization cross sections of each component in a pebble bed high-temperature gas-cooled reactor. For a pebble bed region with a certain mixing ratio, the multi-group homogenization cross sections of each batch of spheres are used, and the multi-group neutron flux of each batch of spheres is obtained based on the collision probability method. The multi-group homogenization cross section of the average sphere in the pebble bed region with the mixing ratio is then calculated. Using the few-group homogenization cross sections of each batch of spheres, the few-group neutron flux of each batch of spheres and the pebble bed voids is obtained based on the collision probability method. The few-group homogenization cross sections in all pebble bed regions are then calculated. Using the few-group homogenization cross sections of the pebble bed region and the reflector assembly, a three-dimensional whole-reactor diffusion calculation is performed to obtain... The minority group neutron flux and leakage rate of each region in the entire reactor are calculated. The multi-group leakage cross section of the pebble bed region is calculated. Using the multi-group homogenization cross section of the average sphere with the corresponding mixing ratio, the multi-group neutron slowing equation is solved to obtain the multi-group neutron leakage energy spectrum of the average sphere in the pebble bed region. The multi-group homogenization cross section of each batch of spheres in the pebble bed region is merged and updated using the multi-group neutron leakage energy spectrum of the average sphere as weight. Based on the updated minority group homogenization cross section, the minority group homogenization cross section of the pebble bed region is calculated again. Three-dimensional whole-reactor diffusion calculation and neutron leakage correction are performed until the minority group homogenization cross section of all pebble bed regions converges, thus completing the neutron leakage correction of the pebble bed core region.

[0046] Taking a pebble bed core with a fuel sphere enrichment of 4.2% and a graphite sphere mixing ratio of 7:8 as an example (the enrichment and mixing ratio can be adjusted according to the specific design), such as... Figure 3 and Figure 4 As shown, the application of neutron leakage correction in pebble bed reactor cores is described, specifically including the following steps:

[0047] Step 1: Use the Monte Carlo particle transport calculation software NECP-MCX to calculate the multi-group and minority-group homogenization cross sections of fuel spheres and graphite spheres with 4.2% enrichment.

[0048] Step 2: Using the multi-group homogenized cross-section of fuel spheres and graphite spheres, and based on the collision probability method, calculate the multi-group neutron flux of fuel spheres and graphite spheres. Then calculate the multi-group homogenized cross-section of the average sphere with a fuel sphere to graphite sphere ratio of 7:8.

[0049] χ ave,h =f fpeb χ fpeb,h +f gpeb χ gpeb,h (1)

[0050]

[0051]

[0052] Among them, f fpeb f gpebThe volume fraction of fuel spheres and graphite spheres in the pebble bed region; χ ave,h The multi-group fission energy spectrum of the h-th energy group of the average sphere with a fuel sphere to graphite sphere ratio of 7:8; χ fpeb,h , χ gpeb,h These are the multi-group fission energy spectra of the h-th energy group of the fuel sphere and the graphite sphere, respectively; Σ ave,x,h The cross section of the multi-group macroscopic reaction of the average sphere h-th energy group with a fuel sphere to graphite sphere ratio of 7:8 is given by φ, where x represents the reaction type, including total reaction, fission reaction, and absorption reaction; fpeb,h φ gpeb,h These represent the multigroup neutron fluxes of the fuel sphere and the graphite sphere in the h-th energy group, respectively; Σ fpeb,x,h Σ gpeb,x,h These are the macroscopic reaction cross sections of the h-th energy group for the fuel sphere and the graphite sphere, respectively; Σ ave,s,h′→h The macroscopic scattering cross section of the average sphere with a fuel sphere to graphite sphere ratio of 7:8, where neutrons from energy group h′ are scattered to energy group h; Σ fpeb,s,h′→h Σ gpeb,s,h′→h These are the macroscopic scattering cross sections of the h′ energy group neutrons from the fuel sphere and graphite sphere to the h energy group, respectively;

[0053] Step 3: Using the few-group homogenization cross-sections of the fuel spheres and graphite spheres, and based on the collision probability method, calculate the few-group neutron fluxes of the fuel spheres, graphite spheres, and sphere bed voids. Then calculate the few-group homogenization cross-sections of all sphere bed regions:

[0054] χ pbed,g =ρ(f fpeb χ fpeb,h +f gpeb χ gpeb,h (4)

[0055]

[0056]

[0057] Where: ρ is the filling rate of the balls in the ball bed area; χ pbed,g The small-group fission energy spectrum of the g-th energy group in the spherical bed region; χ fpeb,g , χ gpeb,g The few-group fission energy spectra of the g-th energy group of fuel spheres and graphite spheres, respectively; Σ pbed,x,h φ represents the macroscopic reaction cross section of the g-th energy group in the spherical bed region, representing the minority group. fpeb,g φ gpeb,g These are the minority group neutron fluxes of the g-th energy group for the fuel sphere and the graphite sphere, respectively; φ 0,g Σ is the minority group neutron flux of the g-th energy group in the spherical bed void; fpeb,x,g Σ gpeb,x,g The macroscopic reaction cross sections of the minority group of the g-th energy group for the fuel sphere and the graphite sphere, respectively; Σ pbed,s,g′→gΣ is the macroscopic scattering cross section of the minority group scattering of neutrons from the g′ energy group in the spherical bed region to the g energy group; fpeb,s,g′→g Σ gpeb,s,g′→g These are the minority group macroscopic scattering cross sections of the neutrons in the g′ energy group scattered into the g energy group from the fuel sphere and the graphite sphere, respectively.

[0058] Step 4: Using the minority group homogenization cross section of the pebble bed region, perform three-dimensional whole-pile diffusion calculations to obtain the minority group neutron flux and minority group neutron leakage rate of each pebble bed region;

[0059] Step 5: Calculate the multi-group leakage cross-section in the pebble bed region. Using the multi-group homogenization cross-section of the average spheres with a fuel sphere to graphite sphere ratio of 7:8, solve the multi-group neutron moderation equation to obtain the multi-group neutron leakage energy spectrum of the average spheres in the pebble bed region:

[0060]

[0061]

[0062] Where, Σ L,h Σ L,g These represent the multi-group and few-group leakage sections in the pebble bed region, respectively; L pbed,g Let g be the minority group neutron leakage rate of the g-th energy group in the sphere bed region; Σ is the minority group neutron flux of the g-th energy group in the sphere bed region; ave,t,h The macroscopic cross section of the h-th energy group of the average sphere with a fuel sphere to graphite sphere ratio of 7:8; (νΣ) ave,f ) h′ The cross section for the multi-group macroscopic fission neutron generation of the h′ energy group of the average sphere with a fuel sphere to graphite sphere ratio of 7:8; k eff φ is the effective proliferation coefficient of the ball bed region. ave,h The energy spectrum of neutron leakage in an average sphere with a fuel sphere to graphite sphere ratio of 7:8 is given.

[0063] Using the multi-group neutron leakage energy spectrum of the average sphere as weights, the few-group homogenization cross-sections of fuel spheres and graphite spheres in the sphere bed region are merged and updated:

[0064]

[0065]

[0066]

[0067]

[0068] Step 6: Repeat steps 3 to 5 until the minority group homogenization cross-sections of all pebble bed regions converge, thus completing the neutron leakage correction in the pebble bed core region.

[0069] Example 2

[0070] Reference Figure 5 This is the second embodiment of the present invention, which differs from the previous embodiment in that it provides a neutron leakage correction system for a pebble bed type high-temperature gas-cooled reactor core, including: a data acquisition module, a model training module, a model verification module, a correction calculation module, and a result display module.

[0071] The data acquisition module is used to collect relevant data of the pebble bed high-temperature gas-cooled reactor, including the multi-group and minority-group homogenization cross sections of the components, the multi-group and minority-group homogenization cross sections of the pebble bed region, and the minority-group neutron flux and minority-group neutron leakage rate in each region of the entire reactor.

[0072] The model training module is used to train the correction model. Based on the data and algorithm, a mathematical model for neutron leakage correction is established through model training.

[0073] The model validation module is used to verify the accuracy and reliability of the modified model obtained through training.

[0074] The correction calculation module uses the trained correction model and real-time collected data to calculate neutron leakage correction. Based on the algorithm and logic of the correction model, it performs real-time correction of neutron leakage in the pebble bed high-temperature gas-cooled reactor and outputs the corrected results.

[0075] The results display module is used to show and visualize the corrected neutron leakage results so that users can analyze and make decisions.

[0076] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0077] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0078] More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0079] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0080] Example 3

[0081] The third embodiment of the present invention differs from the first two embodiments in that it is used to verify and explain the technical effects adopted in the present invention, so as to verify the real effect of the method.

[0082] Using a self-developed high-temperature gas-cooled reactor core physics calculation program to... Figure 1The hybrid pebble bed core model shown was used for calculations to obtain the effective multiplication coefficient keff for three cases: no correction for pebble bed neutron leakage, correction for pebble bed neutron leakage based on multi-group pebble bed cross sections, and correction for pebble bed neutron leakage based on multi-group average pebble bed cross sections. The results were compared with the calculation results of the Monte Carlo physics calculation software NECP-MCX, and the results are shown in Table 1.

[0083] Table 1. k of hybrid pebble bed core eff Comparison of calculation results

[0084]

[0085]

[0086] As can be seen from Table 1, there will be a large calculation deviation if the neutron leakage in the pebble bed is not corrected. While existing technologies can improve the calculation accuracy by correcting the neutron leakage effect in the pebble bed based on multiple pebble bed cross sections, there is still a large calculation deviation. Using the method of the present invention, the neutron leakage effect in the pebble bed can be corrected based on multiple average spherical cross sections, which can significantly reduce the calculation deviation and is closest to the benchmark solution among the three cases. Therefore, the method of the present invention can effectively correct the neutron leakage effect in the pebble bed core and effectively improve the calculation accuracy of the pebble bed high-temperature gas-cooled reactor core.

[0087] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for correcting neutron leakage in the core of a pebble bed type high-temperature gas-cooled reactor, characterized in that: include, The component calculation program was used to calculate the multi-group and minority-group homogenized cross sections of all components of the pebble bed high-temperature gas-cooled reactor. Calculate the multi-group homogenization cross section of the average spheres in all ball bed regions with different mixing ratios and the minority-group homogenization cross section of all ball bed regions; Obtain the minority group neutron flux and minority group neutron leakage rate in each region of the entire reactor; The multi-group neutron leakage energy spectrum of the average sphere is obtained, and the few-group homogenization cross section of each batch of spheres in the sphere bed region is updated. The minority group homogenization cross section of the pebble bed region is calculated, and three-dimensional whole-reactor diffusion calculation and neutron leakage correction are performed. The minority group homogenization cross sections of all pebble bed regions converge, and the neutron leakage correction of the pebble bed core region is completed. The multi-group neutron leakage energy spectrum of the mean sphere includes calculating the multi-group leakage cross-section in the sphere bed region, solving the multi-group neutron slowing equation using the multi-group homogenization cross-section of the mean sphere in the sphere bed region, and obtaining the multi-group neutron leakage energy spectrum of the mean sphere in the sphere bed region. ； ； in, For multiple leakage sections in the ball bed region, For the small number of leakage sections in the ball bed region, For the ball bed area The minority group neutron leakage rate of the energy group For the ball bed area The minority group neutron flux of the energy group The average ball number within the ball bed area The macroscopic total cross section of a multigroup energy group. The average ball number within the ball bed area Multigroup macroscopic fission neutron generation cross section of energy group The effective proliferation coefficient of the ball bed region. The multi-group neutron leakage energy spectrum of the average sphere within the sphere bed region; The few-group homogenization cross section of each batch of spheres within the updated sphere bed region includes, weighted by the multi-group neutron leakage energy spectrum of the average sphere, the few-group homogenization cross section of the fuel spheres and graphite spheres within the updated sphere bed region, expressed as follows: ； ； ； ； in, For fuel ball number The macroscopic reaction cross section of the energy group in multiple groups For graphite spheres The macroscopic reaction cross section of the energy group in multiple groups The average ball number within the ball bed area Energy group neutron scattering to the first The multigroup macroscopic scattering cross section of the energy group For fuel ball number Energy group neutron scattering to the first The multigroup macroscopic scattering cross section of the energy group For graphite spheres Energy group neutron scattering to the first The multigroup macroscopic scattering cross section of the energy group For fuel ball number The macroscopic reaction cross section of a small group of an energy group. For graphite spheres The macroscopic reaction cross section of a small group of an energy group. For fuel ball number Energy group neutron scattering to the first The macroscopic scattering cross section of the energy group in the minority group. For graphite spheres Energy group neutron scattering to the first The macroscopic scattering cross section of a small group energy group.

2. The method for correcting neutron leakage in a pebble bed core of a high-temperature gas-cooled reactor as described in claim 1, characterized in that: The multi-group homogenization cross section of the average spheres within the spherical bed region includes, using the multi-group homogenization cross section of the fuel spheres and graphite spheres, and based on the collision probability method, solving for the multi-group neutron flux of the fuel spheres and graphite spheres. The multi-group homogenization cross section of the average spheres within the spherical bed region is expressed as follows: ； ； ； in, The fuel ball represents the volume fraction of all balls in the sphere bed region. The graphite spheres represent the volume fraction of all the spheres in the sphere bed region. The average ball number within the ball bed area The multigroup fission energy spectrum of the energy group For fuel ball number The multigroup fission energy spectrum of the energy group For graphite spheres The multigroup fission energy spectrum of the energy group The average ball number within the ball bed area The macroscopic reaction cross section of the energy group in multiple groups As for the reaction type, For fuel ball number The multi-group neutron flux of an energy group. For graphite spheres The multi-group neutron flux of an energy group. For fuel ball number The macroscopic reaction cross section of the energy group in multiple groups For graphite spheres The macroscopic reaction cross section of the energy group in multiple groups The average ball number within the ball bed area Energy group neutron scattering to the first Multiple energy groups Group macroscopic scattering cross section, For fuel ball number Energy group neutron scattering to the first The multigroup macroscopic scattering cross section of the energy group For graphite spheres Energy group neutron scattering to the first The macroscopic scattering cross section of the energy group.

3. The method for correcting neutron leakage in a pebble bed core of a high-temperature gas-cooled reactor as described in claim 2, characterized in that: The few-group homogenization cross section of all pebble bed regions includes the few-group homogenization cross section of fuel spheres and graphite spheres. Based on the collision probability method, the few-group neutron flux of fuel spheres, graphite spheres, and pebble bed voids is obtained. The calculated few-group homogenization cross section of all pebble bed regions is expressed as follows: ； ； ； in, The ball filling rate within the ball bed area. For the ball bed area The energy spectrum of small-group fission of energy groups, For fuel ball number The energy spectrum of small-group fission of energy groups, For graphite spheres The energy spectrum of small-group fission of energy groups, For the ball bed area The macroscopic reaction cross section of a small group of an energy group. For fuel ball number The minority group neutron flux of the energy group For graphite spheres The minority group neutron flux of the energy group For the ball bed gap number The minority group neutron flux of the energy group For fuel ball number The macroscopic reaction cross section of a small group of an energy group. For graphite spheres The macroscopic reaction cross section of a small group of an energy group. For the ball bed area Energy group neutron scattering to the first The macroscopic scattering cross section of the energy group in the minority group. For fuel ball number Energy group neutron scattering to the first The macroscopic scattering cross section of the energy group in the minority group. For graphite spheres Energy group neutron scattering to the first The macroscopic scattering cross section of a small group energy group.

4. The method for correcting neutron leakage in a pebble bed core of a high-temperature gas-cooled reactor as described in claim 3, characterized in that: The minority group neutron flux and minority group neutron leakage rate in each region of the entire reactor are obtained by performing three-dimensional whole-reactor diffusion calculations using the minority group homogenization cross section of the pebble bed region.

5. The method for correcting neutron leakage in a pebble bed core of a high-temperature gas-cooled reactor as described in claim 4, characterized in that: The neutron leakage correction in the pebble bed core region includes repeatedly obtaining the minority group neutron flux and minority group neutron leakage rate in each region of the entire reactor, updating the minority group homogenization cross section of each batch of spheres in the pebble bed region, and performing three-dimensional whole-reactor diffusion calculations and neutron leakage correction operations until the minority group homogenization cross section of all pebble bed regions converges, thus completing the neutron leakage correction in the pebble bed core region.

6. A system employing the neutron leakage correction method for a pebble bed type high-temperature gas-cooled reactor core as described in any one of claims 1 to 5, characterized in that: It includes a data acquisition module, a model training module, a model validation module, a correction calculation module, and a results display module; The data acquisition module is used to collect relevant data of the pebble bed type high-temperature gas-cooled reactor, including the multi-group and minority-group homogenization cross sections of the components, the multi-group and minority-group homogenization cross sections of the pebble bed region, and the minority-group neutron flux and minority-group neutron leakage rate of each region of the entire reactor. The model training module is used to train the correction model. Based on the data and algorithm, a mathematical model for neutron leakage correction is established through model training. The model verification module is used to verify the accuracy and reliability of the modified model obtained through training; The correction calculation module uses the trained correction model and real-time collected data to calculate neutron leakage correction. Based on the algorithm and logic of the correction model, it performs real-time correction of neutron leakage in the pebble bed high-temperature gas-cooled reactor and outputs the corrected result. The results display module is used to display and visualize the corrected neutron leakage results so that users can analyze and make decisions.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, it implements the steps of the method for correcting neutron leakage in the core of a pebble bed type high-temperature gas-cooled reactor as described in any one of claims 1 to 5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, it implements the steps of the method for correcting neutron leakage in the core of a pebble bed type high-temperature gas-cooled reactor as described in any one of claims 1 to 5.

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