A method and device for calculating neutron-photon coupled power in a pebble bed high temperature gas cooled reactor

Abstract

This invention proposes a method and apparatus for calculating the neutron-photon coupling power of a pebble bed type high-temperature gas-cooled reactor. The invention includes: performing neutron transport calculations in various regions of the high-temperature gas-cooled reactor to obtain the neutron flux density distribution in each region; combining the neutron flux density distribution with the neutron-generated photon cross section to solve for the neutron-generated photon source distribution in each region; completing photon transport calculations based on the photon source distribution and photon reaction cross section to obtain the photon flux density distribution; and finally, accurately calculating the reactor neutron-photon coupling power distribution by combining the neutron and photon flux density distributions with the kerma factor. This invention can efficiently and accurately obtain the in-reactor coupling power distribution, improving the accuracy of high-temperature gas-cooled reactor power calculations.

Description

Technical Field

[0001] This invention relates to the field of nuclear reactor physics calculation technology, and in particular to a method and apparatus for calculating neutron-photon coupling power in a pebble bed type high-temperature gas-cooled reactor. Background Technology

[0002] The pebble bed high-temperature gas-cooled reactor, as an important reactor type in fourth-generation nuclear energy systems, is widely used in the fields of nuclear reactor physics design and thermal analysis. Core power distribution calculations form the existing system through the coordinated operation of neutron transport, fission rate calculation, and energy deposition. Specifically, the process encompasses the entire process from utilizing the neutron reaction cross section for transport to calculating the fission rate based on the macroscopic fission cross section, including steps such as obtaining neutron flux density.

[0003] However, existing power calculation methods directly use the neutron fission rate and the average energy released per fission cycle to calculate energy deposition, without considering the transport effect of photons generated by neutron reactions. Since neutral particles such as neutrons and photons have long mean free paths, their energy is not deposited in situ. Ignoring photon transport can lead to errors in the calculation of the total core power distribution, or an inability to distinguish between neutron and photon power distributions, thus affecting the accuracy and safety of reactor physics design and thermal analysis. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] Therefore, the first objective of this invention is to propose a method for calculating the neutron-photon coupling power of a pebble bed type high-temperature gas-cooled reactor.

[0006] Another objective of this invention is to provide a neutron-photon coupling power calculation device for a pebble bed type high-temperature gas-cooled reactor.

[0007] The third objective of this invention is to provide a computer device.

[0008] A fourth objective of this invention is to provide a non-transitory computer-readable storage medium.

[0009] To achieve the above objectives, a first aspect of the present invention proposes a method for calculating the neutron-photon coupling power of a pebble bed type high-temperature gas-cooled reactor, comprising:

[0010] S1, perform neutron transport calculations on each region of the pebble bed high-temperature gas-cooled reactor to obtain the neutron flux density distribution in each region; S2, Based on the neutron flux density distribution and the neutron-generated photon cross section, calculate the neutron-generated photon source distribution in each region; S3, using the neutron-generating photon source distribution and photon reaction cross section, photon transport calculations are performed to obtain the photon flux density distribution in each region; S4. Based on the neutron flux density distribution, the photon flux density distribution, and the kerma factor, the neutron-photon coupling power distribution of the pebble bed high-temperature gas-cooled reactor is calculated.

[0011] In one embodiment of the present invention, S1 includes: The pebble bed high-temperature gas-cooled reactor was modeled using a deterministic procedure, then meshed, and the corresponding response matrix was constructed. Neutron transport calculations were performed using the fabricated neutron reaction cross section, and the neutron flux density distribution of each grid in each region was obtained based on the steady-state form of the Boltzmann neutron transport equation. The neutron flux density distribution of each grid in each region is used as input data for subsequent calculations of neutron-generated photon sources.

[0012] In one embodiment of the present invention, S2 includes: When calculating a photon source, it is necessary to consider photons generated by all reaction channels, including fission and radiative trapping as well as inelastic scattering, and calculate the total instantaneous photon generation cross section. The neutron flux density and the prepared neutron-generating photon cross section are used to calculate the neutron-generating photon source, and the photon source distribution of each grid in each pebble bed high-temperature gas-cooled reactor region is obtained. The photon source distribution of each grid in each pebble bed high-temperature gas-cooled reactor region is used for subsequent fixed photon source calculations.

[0013] In one embodiment of the present invention, the calculation of the total transient photon generation cross section includes: In actual calculations, the resonant self-shielding effect of fission and radiation trapping also needs to be considered, and the total transient photon generation cross section after considering the resonant self-shielding is calculated using the formula. The formula for calculating the total transient photon generation cross section considering the resonant self-screen is as follows:

[0014] In the formula, and These represent the neutron fission cross section and the radiation trapping cross section under infinite dilution conditions, respectively. , These are the neutron fission cross section and radiation trapping cross section considering the resonant self-screen, respectively; Output the total transient photon generation cross-section data after considering the resonant self-shielding effect.

[0015] In one embodiment of the present invention, S3 includes: Using a photon source for fixed-source calculations, the photon flux density distribution of each cell in each region of the pebble bed high-temperature gas-cooled reactor was obtained. The photon flux density distribution of each gate element in each region is solved based on the photon fixed source calculation equation, which is:

[0016] in, The total cross-section of the photon. Photon flux The photon scattering cross section A fixed source of photons; The photon flux density distribution of each gate element in each region is output to calculate the neutron-photon coupling power distribution.

[0017] In one embodiment of the present invention, S4 includes: The neutron photon power distribution of the pebble bed high-temperature gas-cooled reactor was calculated using the obtained neutron photon flux density and neutron photon KERMA factor. The total power distribution is obtained based on the formula for calculating the power distribution of neutron-photon coupling. The formula is as follows:

[0018] in, For the first The total KERMA factor of the subgroup, For the first swarm neutron flux density For the first The total KERMA factor of the group photons, For the first Group photon flux density This refers to the volume of each cell in a pebble bed high-temperature gas-cooled reactor. Output the neutron-photon coupling power distribution of the pebble bed type high-temperature gas-cooled reactor.

[0019] In one embodiment of the present invention, it further includes: The precise total power distribution of the pebble bed high-temperature gas-cooled reactor core is obtained based on the neutron-photon coupling power distribution. The neutron power distribution and photon power distribution within the pebble bed high-temperature gas-cooled reactor are obtained based on the neutron-photon coupling power distribution described above. The neutron power distribution, photon power distribution, and total power distribution are used in the physical design and thermal analysis of a pebble bed type high-temperature gas-cooled reactor.

[0020] To achieve the above objectives, a second aspect of the present invention provides a neutron-photon coupling power calculation device for a pebble bed type high-temperature gas-cooled reactor, comprising: The neutron transport calculation module is used to perform neutron transport calculations in various regions of the pebble bed high-temperature gas-cooled reactor to obtain the neutron flux density distribution in each region. The photon source distribution calculation module is used to calculate the neutron-generating photon source distribution in each region based on the neutron flux density distribution and the neutron-generating photon cross section. The photon transport calculation module is used to perform photon transport calculations using the distribution of the neutron-generated photon source and the photon reaction cross section, to obtain the photon flux density distribution in each region. The coupling power calculation module is used to calculate the neutron-photon coupling power distribution of the pebble bed high-temperature gas-cooled reactor based on the neutron flux density distribution, the photon flux density distribution, and the kerma factor.

[0021] The present invention provides a method and apparatus for calculating neutron-photon coupling power in a pebble bed type high-temperature gas-cooled reactor, which effectively solves the problem of inaccurate power calculation caused by the failure to consider the influence of photon transport in the prior art. It can accurately calculate the neutron power distribution, photon power distribution and total power distribution of the pebble bed type high-temperature gas-cooled reactor.

[0022] To achieve the above objectives, a third aspect of this application provides a computer device, including a processor and a memory; wherein the processor runs a program corresponding to the executable program code by reading executable program code stored in the memory, for implementing the method described in the first aspect embodiment.

[0023] To achieve the above objectives, a fourth aspect of this application provides a non-transitory computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the method described in the first aspect.

[0024] Additional aspects and advantages of the invention 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 the invention. Attached Figure Description

[0025] Figure 1 This is a flowchart of a method for calculating neutron-photon coupling power in a pebble bed type high-temperature gas-cooled reactor according to an embodiment of the present invention; Figure 2 This is an architecture diagram of a neutron-photon coupling power calculation system for a pebble bed type high-temperature gas-cooled reactor according to an embodiment of the present invention; Figure 3 This is a structural diagram of a neutron-photon coupling power calculation device for a pebble bed type high-temperature gas-cooled reactor according to an embodiment of the present invention; Figure 4 It is a computer device according to an embodiment of the present invention. Detailed Implementation

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0028] The following description, with reference to the accompanying drawings, describes a method and apparatus for calculating neutron-photon coupling power in a pebble bed type high-temperature gas-cooled reactor according to an embodiment of the present invention.

[0029] Figure 1 This is a flowchart illustrating a method for calculating neutron-photon coupling power in a pebble bed type high-temperature gas-cooled reactor according to an embodiment of the present invention, as shown below. Figure 1 As shown, it includes: S1, perform neutron transport calculations on each region of the pebble bed high-temperature gas-cooled reactor to obtain the neutron flux density distribution in each region; S2, Based on the neutron flux density distribution and the neutron-generated photon cross section, calculate the neutron-generated photon source distribution in each region; S3, using the neutron-generating photon source distribution and photon reaction cross section, photon transport calculations are performed to obtain the photon flux density distribution in each region; S4. Based on the neutron flux density distribution, the photon flux density distribution, and the kerma factor, the neutron-photon coupling power distribution of the pebble bed high-temperature gas-cooled reactor is calculated.

[0030] Figure 2 This is an architecture diagram of the neutron-photon coupling computational system for a pebble bed high-temperature gas-cooled reactor. First, the pebble bed high-temperature gas-cooled reactor is modeled using a deterministic program. Then, a mesh is generated, and the corresponding response matrix is ​​constructed. Neutron transport calculations are performed using the fabricated neutron reaction cross sections to obtain the neutron flux density distribution for each region and each mesh of the pebble bed high-temperature gas-cooled reactor. The neutron reaction cross sections include: total neutron cross section, neutron transport cross section, neutron absorption cross section, neutron scattering cross section, and neutron fission cross section.

[0031] Furthermore, using the obtained neutron flux density and the fabricated neutron-generating photon cross section, the photon source of neutron generation is calculated, yielding the photon source distribution of each grid in the pebble bed high-temperature gas-cooled reactor region. When calculating the photon source, it is necessary to consider photons generated by all reaction channels, including fission and radiative trapping, as well as inelastic scattering, to calculate the total transient photon generation cross section.

[0032] Furthermore, fixed-source calculations were performed using photon sources and various photon reaction cross sections to obtain the photon flux density distribution of each grid in each region of the pebble bed high-temperature gas-cooled reactor. The photon reaction cross section includes: total photon cross section, photon transport cross section, photon absorption cross section, and photon scattering cross section.

[0033] Furthermore, the neutron photon power distribution of the pebble bed high-temperature gas-cooled reactor was calculated using the obtained neutron photon flux density and neutron photon KERMA factor.

[0034] In one embodiment of the present invention, a deterministic model of a pebble bed high-temperature gas-cooled reactor is first performed, followed by mesh generation and construction of the corresponding response matrix. Neutron transport calculations are then performed using the fabricated neutron reaction cross section to obtain the neutron flux density distribution for each region and each mesh. The steady-state Boltzmann neutron transport equation can be expressed as:

[0035] in, For position Location, energy Location, angle neutron angular flux density, For macroscopic scattering transfer cross section, For the overall macroscopic cross section, As a fission source, For other external sources.

[0036] Furthermore, the neutron flux density and the prepared neutron-generating photon cross section are used to calculate the neutron-generating photon source, thus obtaining the photon source distribution of each grid in each pebble bed high-temperature gas-cooled reactor region.

[0037] Furthermore, when calculating the photon source, it is necessary to consider photons generated by all reaction channels, including fission and radiative trapping, as well as inelastic scattering. Therefore, the formula for calculating the total transient photon generation cross section is:

[0038] In the formula, Indicates nuclide i No. g Group neutron fission produces the first h The reaction cross section of group photons Represents nuclide i No. g Group neutron radiation capture produces the first h The reaction cross section of group photons Represents nuclide i No. g Group neutron inelastic scattering produces the first hThe reaction cross section of group photons. It is worth noting that the transient photon generation cross section generated by the NJOY program is under the condition of infinite dilution. In actual calculations, the resonant self-shielding effect of fission and radiative trapping also needs to be considered. The formula for calculating the total transient photon generation cross section after considering the resonant self-shielding is:

[0039] In the formula, and These represent the neutron fission cross section and the radiation trapping cross section under the condition of infinite dilution, respectively. and These are the neutron fission cross section and radiation trapping cross section, respectively, considering the resonant self-screen.

[0040] Furthermore, photon source calculations are performed to obtain the photon source distribution for each grid of the pebble bed high-temperature gas-cooled reactor. The formula for calculating the photon source generated by neutrons is:

[0041] In the formula, nuclide i The nucleon density; To consider the cross-section generated by the transient photons behind the resonant self-screen; Furthermore, fixed-source calculations were performed using a photon source to obtain the photon flux density distribution of each cell in each region of the pebble bed high-temperature gas-cooled reactor.

[0042] The calculation equation for a fixed photon source is:

[0043] in, The total cross-section of the photon. Photon flux The photon scattering cross section It serves as a fixed source of photons.

[0044] Furthermore, the neutron photon power distribution of the pebble bed high-temperature gas-cooled reactor is calculated using the obtained neutron photon flux density and neutron photon KERMA factor. The calculation formula is as follows:

[0045] in, For the first g The total KERMA factor of the subgroup, For the first g swarm neutron flux density For the first h The total KERMA factor of the group photons, Let V be the photon flux density of the h-th group, and V be the volume of each cell in the bed-type high-temperature gas-cooled reactor.

[0046] This invention addresses the problem that existing programs cannot accurately calculate the neutron-photon coupling power of pebble bed high-temperature reactors. First, this invention performs neutron transport calculations on the pebble bed high-temperature gas-cooled reactor to obtain the neutron flux density distribution for each region and grid. Then, it uses the neutron flux density and a fabricated neutron-generating photon cross section to calculate the neutron-generated photon source. Next, it uses the photon source to perform fixed-source calculations to obtain the photon flux density distribution for each region and grid. Finally, it uses the neutron flux density, photon flux density, and the kerma factor of neutrons and photons to calculate the neutron-photon coupling power distribution.

[0047] To achieve the above embodiments, such as Figure 3 As shown, this embodiment also provides a neutron-photon coupling power calculation device 10 for a pebble bed type high-temperature gas-cooled reactor, comprising: The neutron transport calculation module 100 is used to perform neutron transport calculations in various regions of the pebble bed high-temperature gas-cooled reactor to obtain the neutron flux density distribution in each region. The photon source distribution calculation module 200 is used to calculate the neutron-generating photon source distribution in each region based on the neutron flux density distribution and the neutron-generating photon cross section. The photon transport calculation module 300 is used to perform photon transport calculations using the neutron-generated photon source distribution and photon reaction cross section to obtain the photon flux density distribution in each region. The coupling power solving module 400 is used to calculate the neutron-photon coupling power distribution of the pebble bed high-temperature gas-cooled reactor based on the neutron flux density distribution, the photon flux density distribution, and the kerma factor.

[0048] The present invention provides a neutron-photon coupling power calculation device for a pebble bed type high-temperature gas-cooled reactor, which effectively solves the problem of inaccurate power calculation caused by the failure to consider the influence of photon transport in the prior art. It can accurately calculate the neutron power distribution, photon power distribution and total power distribution of the pebble bed type high-temperature gas-cooled reactor.

[0049] To implement the methods of the above embodiments, the present invention also provides a computer device, such as... Figure 4 As shown, the computer device 600 includes a memory 601 and a processor 602; wherein, the processor 602 reads executable program code stored in the memory 601 to run a program corresponding to the executable program code, so as to implement the various steps of the method described above.

[0050] To implement the above embodiments, this application also proposes a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the method described in the foregoing embodiments.

[0051] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. 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.

[0052] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

Claims

1. A method for calculating neutron-photon coupling power in a pebble bed type high-temperature gas-cooled reactor, characterized in that, include: S1, perform neutron transport calculations on each region of the pebble bed high-temperature gas-cooled reactor to obtain the neutron flux density distribution in each region; S2, Based on the neutron flux density distribution and the neutron-generated photon cross section, calculate the neutron-generated photon source distribution in each region; S3, using the neutron-generating photon source distribution and photon reaction cross section, photon transport calculations are performed to obtain the photon flux density distribution in each region; S4. Based on the neutron flux density distribution, the photon flux density distribution, and the kerma factor, the neutron-photon coupling power distribution of the pebble bed high-temperature gas-cooled reactor is calculated.

2. The method as described in claim 1, characterized in that, S1 includes: The pebble bed high-temperature gas-cooled reactor was modeled using a deterministic procedure, then meshed, and the corresponding response matrix was constructed. Neutron transport calculations were performed using the fabricated neutron reaction cross section, and the neutron flux density distribution of each grid in each region was obtained based on the steady-state form of the Boltzmann neutron transport equation. The neutron flux density distribution of each grid in each region is used as input data for subsequent calculations of neutron-generated photon sources.

3. The method as described in claim 1, characterized in that, The S2 includes: When calculating a photon source, it is necessary to consider photons generated by all reaction channels, including fission and radiative trapping as well as inelastic scattering, and calculate the total instantaneous photon generation cross section. The neutron flux density and the prepared neutron-generating photon cross section are used to calculate the neutron-generating photon source, and the photon source distribution of each grid in each pebble bed high-temperature gas-cooled reactor region is obtained. The photon source distribution of each grid in each pebble bed high-temperature gas-cooled reactor region is used for subsequent fixed photon source calculations.

4. The method as described in claim 3, characterized in that, The calculation of the total transient photon generation cross section includes: In actual calculations, the resonant self-shielding effect of fission and radiation trapping also needs to be considered, and the total transient photon generation cross section after considering the resonant self-shielding is calculated using the formula. The formula for calculating the total transient photon generation cross section considering the resonant self-screen is as follows: In the formula, and These represent the neutron fission cross section and the radiation trapping cross section under infinite dilution conditions, respectively. , These are the neutron fission cross section and radiation trapping cross section considering the resonant self-screen, respectively; Output the total transient photon generation cross-section data after considering the resonant self-shielding effect.

5. The method as described in claim 1, characterized in that, The S3 includes: Using a photon source for fixed-source calculations, the photon flux density distribution of each cell in each region of the pebble bed high-temperature gas-cooled reactor was obtained. The photon flux density distribution of each gate element in each region is solved based on the photon fixed source calculation equation, which is: in, The total cross-section of the photon. Photon flux The photon scattering cross section A fixed source of photons; The photon flux density distribution of each gate element in each region is output to calculate the neutron-photon coupling power distribution.

6. The method as described in claim 1, characterized in that, The S4 includes: The neutron photon power distribution of the pebble bed high-temperature gas-cooled reactor was calculated using the obtained neutron photon flux density and neutron photon KERMA factor. The total power distribution is obtained based on the formula for calculating the power distribution of neutron-photon coupling. The formula is as follows: in, For the first The total KERMA factor of the subgroup, For the first swarm neutron flux density For the first The total KERMA factor of the group photons, For the first Group photon flux density, This refers to the volume of each cell in a pebble bed high-temperature gas-cooled reactor. Output the neutron-photon coupling power distribution of the pebble bed type high-temperature gas-cooled reactor.

7. The method as described in claim 6, characterized in that, The method further includes: The precise total power distribution of the pebble bed high-temperature gas-cooled reactor core is obtained based on the neutron-photon coupling power distribution. The neutron power distribution and photon power distribution within the pebble bed high-temperature gas-cooled reactor are obtained based on the neutron-photon coupling power distribution described above. The neutron power distribution, photon power distribution, and total power distribution are used in the physical design and thermal analysis of a pebble bed type high-temperature gas-cooled reactor.

8. A neutron-photon coupling power calculation device for a pebble bed type high-temperature gas-cooled reactor, characterized in that, include: The neutron transport calculation module is used to perform neutron transport calculations in various regions of the pebble bed high-temperature gas-cooled reactor to obtain the neutron flux density distribution in each region. The photon source distribution calculation module is used to calculate the neutron-generating photon source distribution in each region based on the neutron flux density distribution and the neutron-generating photon cross section. The photon transport calculation module is used to perform photon transport calculations using the distribution of the neutron-generated photon source and the photon reaction cross section, to obtain the photon flux density distribution in each region. The coupling power calculation module is used to calculate the neutron-photon coupling power distribution of the pebble bed high-temperature gas-cooled reactor based on the neutron flux density distribution, the photon flux density distribution, and the kerma factor.

9. A computer device, characterized in that, Including processor and memory; The processor reads executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement the method as described in any one of claims 1-7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1-7.

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