Method and system for determining high temperature gas cooled reactor pebble bed homogenization buckling constant

Abstract

The application provides a method and system for determining high-temperature gas cooled reactor pebble bed homogenization group constant, the method comprising: obtaining different batches of balls in a high-temperature gas cooled reactor pebble bed core, and then arranging and combining the balls to obtain each combination model of different batch combinations; determining the multi-group neutron flux ratio of each batch of balls in each combination model by using a Monte Carlo method, and constructing a multi-group neutron flux ratio table of each batch of balls in each combination model; in the multi-group neutron flux ratio table, selecting the multi-group neutron flux ratio of each batch of balls in each combination model in the current high-temperature gas cooled reactor pebble bed core; and determining the homogenization group constant of the current high-temperature gas cooled reactor pebble bed region according to the selected multi-group neutron flux ratio. The technical scheme provided by the application improves the calculation speed of the high-temperature gas cooled reactor pebble bed homogenization group constant without reducing the calculation precision, and saves the calculation resources.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of homogenization group constant calculation, in particular to a method and system for determining the homogenization group constant of a pebble bed of a high temperature gas cooled reactor. BACKGROUND

[0002] During the operation of a pebble bed high temperature gas cooled reactor, fuel pebbles and graphite pebbles flow slowly from top to bottom in the pebble bed core, a small part of the pebbles flowing out of the core will be replaced by new fuel pebbles and loaded into the core, and most of the pebbles flowing out of the core will be returned to the core for recycling, so the core is composed of pebbles (fuel pebbles and graphite pebbles) of different batches (different fuel enrichment, burnup level and temperature distribution).

[0003] The mixed pebble bed homogenization group constant required for the core diffusion calculation of a pebble bed high temperature gas cooled reactor needs to be obtained by merging the multi-group neutron flux distribution and homogenization group constant of each batch of pebbles in the pebble bed region. In the past, it was necessary to calculate the collision probability of each batch of pebbles for each region of the pebble bed, and then solve the collision probability equation set to obtain the multi-group neutron flux distribution of each batch of pebbles, which requires a large amount of calculation time and computing resources. SUMMARY

[0004] The method and system for determining the homogenization group constant of a pebble bed of a high temperature gas cooled reactor provided by the present application at least solve the technical problem of requiring a large amount of calculation time and computing resources when determining the homogenization group constant of a pebble bed of a high temperature gas cooled reactor.

[0005] The first aspect of the present application provides a method for determining the homogenization group constant of a pebble bed of a high temperature gas cooled reactor, the method comprising:

[0006] obtaining pebbles of different batches in the pebble bed core of a high temperature gas cooled reactor, and then arranging and combining the pebbles to obtain each combination model of different batch combinations;

[0007] determining the multi-group neutron flux ratio of each batch of pebbles in each combination model by using the Monte Carlo method, and constructing a multi-group neutron flux ratio table of each batch of pebbles in each combination model;

[0008] selecting the multi-group neutron flux ratio of each batch of pebbles in each combination model in the current pebble bed core of a high temperature gas cooled reactor from the multi-group neutron flux ratio table based on the quantity information, temperature distribution and burnup level of each batch of pebbles in the current pebble bed core of a high temperature gas cooled reactor;

[0009] determining the homogenization group constant of the current pebble bed region of a high temperature gas cooled reactor according to the multi-group neutron flux ratio of each batch of pebbles in each combination model in the current pebble bed core of a high temperature gas cooled reactor.

[0010] Preferably, the obtaining of the pebbles of different batches in the pebble bed core of a high temperature gas cooled reactor comprises:

[0011] Based on the fuel enrichment, burnup level, and temperature distribution of the fuel balls in the high-temperature gas-cooled reactor pebble bed core, the fuel balls are divided into different batches. At the same time, the graphite balls in the high-temperature gas-cooled reactor pebble bed core are divided into a different batch than the fuel balls.

[0012] Furthermore, the formulas for calculating the multi-group neutron flux ratio of each batch of spheres in each combined model are as follows:

[0013]

[0014] In the formula, Let g be the neutron flux ratio of the i-th batch of spheres in the g-th energy group of the k-th combination model. Let be the neutron flux density of the g-th energy group of the i-th batch of the k-th combination model, where i ∈ [1~I] and I is the total number of batches in the k-th combination model.

[0015] Preferably, determining the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux ratio of each batch of spheres in each combined model in the current high-temperature gas-cooled reactor pebble bed core includes:

[0016] Obtain the interpolation weight coefficients corresponding to each combined model;

[0017] The multi-group neutron flux of each batch of balls in the current high-temperature gas-cooled reactor pebble bed region is determined based on the interpolation weight coefficients corresponding to each combined model and the multi-group neutron flux ratio of each batch of balls in each combined model in the current high-temperature gas-cooled reactor pebble bed core.

[0018] Based on the multi-group neutron flux of each batch of spheres in the current high-temperature gas-cooled reactor pebble bed region, the homogenization group constant of the previous high-temperature gas-cooled reactor pebble bed region is determined.

[0019] Furthermore, the calculation formula for the multi-group neutron flux of each batch of spheres in the current high-temperature gas-cooled reactor pebble bed region is as follows:

[0020]

[0021] In the formula, φ i,g This represents the neutron flux ratio of the i-th batch of spheres in the g-th energy group within the current high-temperature gas-cooled reactor pebble bed region. Let a be the neutron flux ratio of the i-th batch of spheres in the g-th energy group of the k-th combination model. k is the interpolation weight coefficient corresponding to the k-th combined model, k∈[1~K], where K is the number of combined models.

[0022] Furthermore, the formula for calculating the homogenization group constant of the pre-determined high-temperature gas-cooled reactor pebble bed region is as follows:

[0023]

[0024] In the formula, Let f be the homogenized macroscopic reaction cross section of the g-th energy group in the pre-high temperature gas-cooled reactor pebble bed region, where x represents the reaction type, including total, fission, and absorption reactions, and f is the homogenized macroscopic reaction cross section. i Let Σ be the volume fraction of the region occupied by the i-th batch of spheres. i,x,g Let g be the macroscopic reaction cross section of the i-th batch of spheres in the g-th energy group. Let φ be the macroscopic scattering cross section of the neutrons from the i-th batch of spheres in the g'-th energy group scattered into the g-th energy group. i,g′ Σ represents the neutron flux ratio of the i-th batch of spheres in the g' energy group within the current high-temperature gas-cooled reactor pebble bed region. i,s,g′→g Let g' be the macroscopic scattering cross section of the energy group of the i-th batch of spheres.

[0025] The second aspect of this application proposes a system for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed, comprising:

[0026] The acquisition module is used to acquire different batches of balls in the pebble bed core of the high-temperature gas-cooled reactor, and then arrange and combine the balls to obtain various combination models of different batches;

[0027] The first determining module is used to determine the multi-group neutron flux ratio of each batch of spheres in each combined model using the Monte Carlo method, and to construct a multi-group neutron flux ratio table for each batch of spheres in each combined model.

[0028] The selection module is used to select the multi-group neutron flux ratio of each batch of balls in each combination model in the current high-temperature gas-cooled reactor pebble bed core based on the quantity information, temperature distribution, and burnup level of each batch of balls in the current high-temperature gas-cooled reactor pebble bed core in the multi-group neutron flux ratio table.

[0029] The second determining module is used to determine the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux ratio of each batch of spheres in each combination model in the current high-temperature gas-cooled reactor pebble bed core.

[0030] Preferably, obtaining different batches of pellets from the high-temperature gas-cooled reactor pebble bed core includes:

[0031] Based on the fuel enrichment, burnup level, and temperature distribution of the fuel balls in the high-temperature gas-cooled reactor pebble bed core, the fuel balls are divided into different batches. At the same time, the graphite balls in the high-temperature gas-cooled reactor pebble bed core are divided into a different batch than the fuel balls.

[0032] Preferably, the formula for calculating the multi-group neutron flux ratio of each batch of spheres in each combined model is as follows:

[0033]

[0034] In the formula, Let g be the neutron flux ratio of the i-th batch of spheres in the g-th energy group of the k-th combination model. Let be the neutron flux density of the g-th energy group of the i-th batch of the k-th combination model, where i ∈ [1~I] and I is the total number of batches in the k-th combination model.

[0035] Preferably, the second determining module includes:

[0036] The acquisition unit is used to acquire the interpolation weight coefficients corresponding to each combined model.

[0037] The first determining unit is used to determine the multi-group neutron flux of each batch of balls in the current high-temperature gas-cooled reactor pebble bed region based on the interpolation weight coefficients corresponding to each combined model and the multi-group neutron flux ratio of each batch of balls in each combined model in the current high-temperature gas-cooled reactor pebble bed core.

[0038] The second determining unit is used to determine the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux of each batch of spheres in the current high-temperature gas-cooled reactor pebble bed region.

[0039] The technical solutions provided by the embodiments of this application bring at least the following beneficial effects:

[0040] This application proposes a method and system for determining the homogenization group constant of a high-temperature gas-cooled reactor (HTGR) pebble bed. The method includes acquiring spheres from different batches within the HTGR pebble bed core, arranging and combining the spheres to obtain various combination models of different batches; determining the multi-group neutron flux ratio of each batch of spheres in each combination model using the Monte Carlo method, and constructing a multi-group neutron flux ratio table for each batch of spheres in each combination model; selecting the multi-group neutron flux ratio of each batch of spheres in each combination model of the current HTGR pebble bed core from the multi-group neutron flux ratio table based on the quantity information, temperature distribution, and burnup level of each batch of spheres in the current HTGR pebble bed core; and determining the homogenization group constant of the current HTGR pebble bed region based on the multi-group neutron flux ratio of each batch of spheres in each combination model of the current HTGR pebble bed core. The technical solution proposed in this application improves the calculation speed of the homogenization group constant of the HTGR pebble bed without reducing calculation accuracy, thus saving computational resources.

[0041] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0042] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0043] Figure 1This is a flowchart illustrating a method for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed according to an embodiment of this application;

[0044] Figure 2 This is a structural diagram of a system for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed according to an embodiment of this application;

[0045] Figure 3 This is a structural diagram of a second determining module provided according to an embodiment of this application. Detailed Implementation

[0046] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0047] This application proposes a method and system for determining the homogenization group constant of a high-temperature gas-cooled reactor (HTGR) pebble bed. The method includes acquiring spheres from different batches within the HTGR pebble bed core, arranging and combining the spheres to obtain various combination models of different batches; determining the multi-group neutron flux ratio of each batch of spheres in each combination model using the Monte Carlo method, and constructing a multi-group neutron flux ratio table for each batch of spheres in each combination model; selecting the multi-group neutron flux ratio of each batch of spheres in each combination model of the current HTGR pebble bed core from the multi-group neutron flux ratio table based on the quantity information, temperature distribution, and burnup level of each batch of spheres in the current HTGR pebble bed core; and determining the homogenization group constant of the current HTGR pebble bed region based on the multi-group neutron flux ratio of each batch of spheres in each combination model of the current HTGR pebble bed core. The technical solution proposed in this application improves the calculation speed of the homogenization group constant of the HTGR pebble bed without reducing calculation accuracy, thus saving computational resources.

[0048] The method and system for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed according to embodiments of this application are described below with reference to the accompanying drawings.

[0049] Example 1

[0050] Figure 1 This is a flowchart illustrating a method for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed according to an embodiment of this application, as shown below. Figure 1 As shown, the method includes:

[0051] Step 1: Obtain spheres from different batches in the high-temperature gas-cooled reactor pebble bed core, and then arrange and combine the spheres to obtain various combination models of different batches;

[0052] The process of obtaining different batches of pellets from the high-temperature gas-cooled reactor pellet bed core includes:

[0053] Based on the fuel enrichment, burnup level, and temperature distribution of the fuel balls in the high-temperature gas-cooled reactor pebble bed core, the fuel balls are divided into different batches. At the same time, the graphite balls in the high-temperature gas-cooled reactor pebble bed core are divided into a different batch than the fuel balls.

[0054] Step 2: Use the Monte Carlo method to determine the multi-group neutron flux ratio of each batch of spheres in each combined model, and construct a multi-group neutron flux ratio table for each batch of spheres in each combined model.

[0055] It should be noted that the formula for calculating the multi-group neutron flux ratio of each batch of spheres in each combined model is as follows:

[0056]

[0057] In the formula, Let g be the neutron flux ratio of the i-th batch of spheres in the g-th energy group of the k-th combination model. Let be the neutron flux density of the g-th energy group of the i-th batch of the k-th combination model, where i ∈ [1~I] and I is the total number of batches in the k-th combination model.

[0058] For example, fuel pellets with different fuel enrichment, different burnup levels, and different temperatures in the pebble bed core of a high-temperature gas-cooled reactor are divided into different batches of pellets, and graphite pellets in the pebble bed are treated as a special batch of pellets.

[0059] A series of physical models containing different proportions and batches of spheres (fuel spheres and graphite spheres) are constructed in a permutation and combination manner. The Monte Carlo physics calculation program is used to perform neutron transport calculations on the combination models of spheres with different permutations and combinations to obtain the multi-group neutron flux density of each batch of spheres in each combination, and then obtain the multi-group neutron flux ratio of each batch of spheres in each combination. The calculation program can be NECP-MCX.

[0060] The data for a combination includes the multi-group neutron flux ratios of each batch of spheres in that combination, with each combination's data occupying a position in the table, thus creating a multi-group neutron flux ratio table for the combination of spheres in a high-temperature gas-cooled reactor.

[0061] Step 3: Based on the quantity information, temperature distribution, and burnup level of each batch of pellets in the current high-temperature gas-cooled reactor pebble bed core, select the multi-group neutron flux ratio of each batch of pellets in the multi-group neutron flux ratio table in the current high-temperature gas-cooled reactor pebble bed core.

[0062] Step 4: Determine the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux ratio of each batch of spheres in each combination model in the current high-temperature gas-cooled reactor pebble bed core.

[0063] In this embodiment of the disclosure, step 4 specifically includes:

[0064] Step 4-1: Obtain the interpolation weight coefficients corresponding to each combined model;

[0065] Step 4-2: Determine the multi-group neutron flux of each batch of spheres in the current high-temperature gas-cooled reactor pebble bed region based on the interpolation weight coefficients corresponding to each combined model and the multi-group neutron flux ratio of each batch of spheres in each combined model in the current high-temperature gas-cooled reactor pebble bed core.

[0066] Furthermore, the calculation formula for the multi-group neutron flux of each batch of spheres in the current high-temperature gas-cooled reactor pebble bed region is as follows:

[0067]

[0068] In the formula, φ i,g This represents the neutron flux ratio of the i-th batch of spheres in the g-th energy group within the current high-temperature gas-cooled reactor pebble bed region. Let a be the neutron flux ratio of the i-th batch of spheres in the g-th energy group of the k-th combination model. k is the interpolation weight coefficient corresponding to the k-th combined model, k∈[1~K], where K is the number of combined models.

[0069] It should be noted that, The formula must satisfy the following conditions to be true. In the formula, ζ i n represents the proportion of the i-th batch of balls in the core region of the ball bed. i Let represent the number of balls in the i-th batch within the core region of the ball bed.

[0070] For example, based on the quantity, temperature distribution, and burnup level of each batch of balls in the core region of the pebble bed under actual operating conditions, several combination data with balls from the same batch are selected from the multi-group neutron flux ratio table of high-temperature gas-cooled reactor spherical element combinations. Then, appropriate interpolation weighting coefficients are selected for interpolation calculation to obtain the multi-group neutron flux ratio of each batch of balls in a certain region of the hybrid pebble bed under actual operating conditions.

[0071] Step 4-3: Determine the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux of each batch of spheres in the current high-temperature gas-cooled reactor pebble bed region.

[0072] Furthermore, the formula for calculating the homogenization group constant of the pre-determined high-temperature gas-cooled reactor pebble bed region is as follows:

[0073]

[0074] In the formula, Let f be the homogenized macroscopic reaction cross section of the g-th energy group in the pre-high temperature gas-cooled reactor pebble bed region, where x represents the reaction type, including total, fission, and absorption reactions, and f is the homogenized macroscopic reaction cross section. i Let Σ be the volume fraction of the region occupied by the i-th batch of spheres. i,x,g Let g be the macroscopic reaction cross section of the i-th batch of spheres in the g-th energy group. Let φ be the macroscopic scattering cross section of the neutrons from the i-th batch of spheres in the g'-th energy group scattered into the g-th energy group. i,g′ Σ represents the neutron flux ratio of the i-th batch of spheres in the g' energy group within the current high-temperature gas-cooled reactor pebble bed region. i,s,g′→g Let g' be the macroscopic scattering cross section of the energy group of the i-th batch of spheres.

[0075] In summary, the method for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed proposed in this embodiment only requires the multi-group relative neutron flux density of each batch of spheres, i.e., the multi-group neutron flux ratio. Therefore, by prefabricating the multi-group neutron flux ratio table of the prefabricated high-temperature gas-cooled reactor spherical element combination, the multi-group neutron flux ratio of each batch of spheres under actual operating conditions can be obtained by direct interpolation calculation in each subsequent fuel cycle calculation. This eliminates the complex collision probability calculation process and collision probability equation solution process, thereby significantly reducing calculation time and computational resources without reducing calculation accuracy.

[0076] Example 2

[0077] Figure 2 This application provides a system for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed according to one embodiment of the present application, such as... Figure 2 As shown, it includes:

[0078] The acquisition module 100 is used to acquire different batches of balls in the pebble bed core of the high-temperature gas-cooled reactor, and then arrange and combine the balls to obtain different combination models of different batches.

[0079] The first determining module 200 is used to determine the multi-group neutron flux ratio of each batch of spheres in each combined model using the Monte Carlo method, and to construct a multi-group neutron flux ratio table for each batch of spheres in each combined model.

[0080] Module 300 is selected to select the multi-group neutron flux ratio of each batch of balls in each combination model in the current high-temperature gas-cooled reactor pebble bed core based on the quantity information, temperature distribution, and burnup level of each batch of balls in the current high-temperature gas-cooled reactor pebble bed core in the multi-group neutron flux ratio table.

[0081] The second determining module 400 is used to determine the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux ratio of each batch of spheres in each combination model in the current high-temperature gas-cooled reactor pebble bed core.

[0082] In this embodiment of the disclosure, obtaining different batches of pellets from the high-temperature gas-cooled reactor pebble bed core includes:

[0083] Based on the fuel enrichment, burnup level, and temperature distribution of the fuel balls in the high-temperature gas-cooled reactor pebble bed core, the fuel balls are divided into different batches. At the same time, the graphite balls in the high-temperature gas-cooled reactor pebble bed core are divided into a different batch than the fuel balls.

[0084] In this embodiment of the disclosure, the formula for calculating the multi-group neutron flux ratio of each batch of spheres in each combined model is as follows:

[0085]

[0086] In the formula, Let g be the neutron flux ratio of the i-th batch of spheres in the g-th energy group of the k-th combination model. Let be the neutron flux density of the g-th energy group of the i-th batch of the k-th combination model, where i ∈ [1~I] and I is the total number of batches in the k-th combination model.

[0087] In the embodiments disclosed herein, such as Figure 3 As shown, the second determining module 400 includes:

[0088] The acquisition unit 401 is used to acquire the interpolation weight coefficients corresponding to each combined model;

[0089] The first determining unit 402 is used to determine the multi-group neutron flux of each batch of balls in the current high-temperature gas-cooled reactor pebble bed region based on the interpolation weight coefficients corresponding to each combined model and the multi-group neutron flux ratio of each batch of balls in each combined model in the current high-temperature gas-cooled reactor pebble bed core.

[0090] The second determining unit 403 is used to determine the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux of each batch of spheres in the current high-temperature gas-cooled reactor pebble bed region.

[0091] It should be noted that the calculation formula for the multi-group neutron flux of each batch of spheres in the current high-temperature gas-cooled reactor pebble bed region is as follows:

[0092]

[0093] In the formula, φ i,g This represents the neutron flux ratio of the i-th batch of spheres in the g-th energy group within the current high-temperature gas-cooled reactor pebble bed region. Let a be the neutron flux ratio of the i-th batch of spheres in the g-th energy group of the k-th combination model.k is the interpolation weight coefficient corresponding to the k-th combined model, k∈[1~K], where K is the number of combined models.

[0094] The formula for calculating the homogenization group constant of the pre-determined high-temperature gas-cooled reactor pebble bed region is as follows:

[0095]

[0096] In the formula, Let f be the homogenized macroscopic reaction cross section of the g-th energy group in the pre-high temperature gas-cooled reactor pebble bed region, where x represents the reaction type, including total, fission, and absorption reactions, and f is the homogenized macroscopic reaction cross section. i Let Σ be the volume fraction of the region occupied by the i-th batch of spheres. i,x,g Let g be the macroscopic reaction cross section of the i-th batch of spheres in the g-th energy group. Let φ be the macroscopic scattering cross section of the neutrons from the i-th batch of spheres in the g'-th energy group scattered into the g-th energy group. i,g′ Σ represents the neutron flux ratio of the i-th batch of spheres in the g' energy group within the current high-temperature gas-cooled reactor pebble bed region. i,s,g′→g Let g' be the macroscopic scattering cross section of the energy group of the i-th batch of spheres.

[0097] In summary, the system proposed in this embodiment for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed significantly reduces computation time and resources without compromising computational accuracy.

[0098] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0099] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0100] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A method for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed, characterized in that, The method includes: Different batches of balls were obtained from the pebble bed core of a high-temperature gas-cooled reactor, and then the balls were arranged and combined to obtain different combination models of different batches. The Monte Carlo method was used to determine the multi-group neutron flux ratio of each batch of spheres in each combined model, and the multi-group neutron flux ratio of each batch of spheres in each combined model was used to construct a multi-group neutron flux ratio table. Based on the quantity information, temperature distribution, and burnup level of each batch of pellets in the current high-temperature gas-cooled reactor pebble bed core, the multi-group neutron flux ratio of each batch of pellets in each combination model in the current high-temperature gas-cooled reactor pebble bed core is selected from the multi-group neutron flux ratio table in the table of multi-group neutron flux ratios. The homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region is determined based on the multi-group neutron flux ratio of each batch of spheres in each combined model in the current high-temperature gas-cooled reactor pebble bed core. The formula for calculating the homogenization group constant is as follows: In the formula, Let be the homogenized macroscopic reaction cross section of the g-th energy group in the pre-determined high-temperature gas-cooled reactor pebble bed region, where Indicates the reaction type, including total reaction, fission reaction, absorption reaction, etc. Let i be the volume fraction of the region occupied by the i-th batch of spheres. Let g be the macroscopic reaction cross section of the i-th batch of spheres in the g-th energy group. For the i-th batch of balls The macroscopic scattering cross section of neutrons from one energy group to the g-th energy group. The i-th batch of pellets in the current high-temperature gas-cooled reactor pellet bed region The neutron flux ratio of the energy group For the i-th batch of balls Macroscopic scattering cross section of the energy group.

2. The method as described in claim 1, characterized in that, The process of obtaining different batches of pellets from the high-temperature gas-cooled reactor pebble bed core includes: Based on the fuel enrichment, burnup level, and temperature distribution of the fuel balls in the high-temperature gas-cooled reactor pebble bed core, the fuel balls are divided into different batches. At the same time, the graphite balls in the high-temperature gas-cooled reactor pebble bed core are divided into a different batch than the fuel balls.

3. The method as described in claim 1, characterized in that, The formulas for calculating the multi-group neutron flux ratio of each batch of spheres in each combined model are as follows: In the formula, For the first The first combination model Batch of balls The neutron flux ratio of the energy group For the first The first combination model Batch of balls Neutron flux density of the energy group , For the first The total number of batches in the combined model.

4. The method as described in claim 1, characterized in that, The determination of the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux ratio of each batch of spheres in each combined model in the current high-temperature gas-cooled reactor pebble bed core includes: Obtain the interpolation weight coefficients corresponding to each combined model; The multi-group neutron flux of each batch of balls in the current high-temperature gas-cooled reactor pebble bed region is determined based on the interpolation weight coefficients corresponding to each combined model and the multi-group neutron flux ratio of each batch of balls in each combined model in the current high-temperature gas-cooled reactor pebble bed core. The homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region is determined based on the multi-group neutron flux of each batch of pebbles within the current high-temperature gas-cooled reactor pebble bed region.

5. The method as described in claim 4, characterized in that, The formula for calculating the multi-group neutron flux of each batch of pellets in the current high-temperature gas-cooled reactor pebble bed region is as follows: In the formula, This represents the neutron flux ratio of the i-th batch of spheres in the g-th energy group within the current high-temperature gas-cooled reactor pebble bed region. For the first The first combination model Batch of balls The neutron flux ratio of the energy group For the first The interpolation weight coefficients corresponding to each combined model , This represents the number of combined models.

6. A system for determining the homogenization group constant of a high-temperature gas-cooled reactor pebble bed, characterized in that, include: The acquisition module is used to acquire different batches of balls in the pebble bed core of the high-temperature gas-cooled reactor, and then arrange and combine the balls to obtain various combination models of different batches; The first determining module is used to determine the multi-group neutron flux ratio of each batch of spheres in each combined model using the Monte Carlo method, and to construct a multi-group neutron flux ratio table for each batch of spheres in each combined model. The selection module is used to select the multi-group neutron flux ratio of each batch of balls in each combination model in the current high-temperature gas-cooled reactor pebble bed core based on the quantity information, temperature distribution, and burnup level of each batch of balls in the current high-temperature gas-cooled reactor pebble bed core in the multi-group neutron flux ratio table. The second determining module is used to determine the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux ratio of each batch of spheres in each combined model in the current high-temperature gas-cooled reactor pebble bed core. The formula for calculating the homogenization group constant is as follows: In the formula, Let be the homogenized macroscopic reaction cross section of the g-th energy group in the pre-determined high-temperature gas-cooled reactor pebble bed region, where Indicates the reaction type, including total reaction, fission reaction, absorption reaction, etc. Let i be the volume fraction of the region occupied by the i-th batch of spheres. Let g be the macroscopic reaction cross section of the i-th batch of spheres in the g-th energy group. For the i-th batch of balls The macroscopic scattering cross section of neutrons from one energy group to the g-th energy group. The i-th batch of pellets in the current high-temperature gas-cooled reactor pellet bed region The neutron flux ratio of the energy group For the i-th batch of balls Macroscopic scattering cross section of the energy group.

7. The system as described in claim 6, characterized in that, The process of obtaining different batches of pellets from the high-temperature gas-cooled reactor pebble bed core includes: Based on the fuel enrichment, burnup level, and temperature distribution of the fuel balls in the high-temperature gas-cooled reactor pebble bed core, the fuel balls are divided into different batches. At the same time, the graphite balls in the high-temperature gas-cooled reactor pebble bed core are divided into a different batch than the fuel balls.

8. The system as described in claim 6, characterized in that, The formulas for calculating the multi-group neutron flux ratio of each batch of spheres in each combined model are as follows: In the formula, For the first The first combination model Batch of balls The neutron flux ratio of the energy group For the first The first combination model Batch of balls Neutron flux density of the energy group , For the first The total number of batches in the combined model.

9. The system as described in claim 6, characterized in that, The second determining module includes: The acquisition unit is used to acquire the interpolation weight coefficients corresponding to each combined model. The first determining unit is used to determine the multi-group neutron flux of each batch of balls in the current high-temperature gas-cooled reactor pebble bed region based on the interpolation weight coefficients corresponding to each combined model and the multi-group neutron flux ratio of each batch of balls in each combined model in the current high-temperature gas-cooled reactor pebble bed core. The second determining unit is used to determine the homogenization group constant of the current high-temperature gas-cooled reactor pebble bed region based on the multi-group neutron flux of each batch of spheres in the current high-temperature gas-cooled reactor pebble bed region.

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