Neutron flux density relative distribution measurement method and device, and neutron parameter determination method and system

Abstract

This application discloses a method and apparatus for measuring the relative distribution of neutron flux density, and a method and system for determining neutron parameters, relating to the field of nuclear industry technology. M first optical fibers are respectively arranged at the test location in the zero-power device core of their corresponding locations; each first optical fiber is filled with a neutron-sensitive material; M is a positive integer; the method includes: acquiring the luminous intensity of the first optical fiber corresponding to each test location to obtain M luminous intensities; and determining the relative distribution of neutron flux density at each test location based on the M luminous intensities. According to the embodiments of this application, this method can reduce disturbances to the neutron field within the reactor and can quickly and easily monitor the relative distribution of neutron flux density within the reactor in real time.

Description

Technical Field

[0001] This application belongs to the field of nuclear industry technology, specifically relating to a method and apparatus for measuring the relative distribution of neutron flux density, and a method and system for determining neutron parameters. Background Technology

[0002] Zero-power devices are a key means of verifying critical reactor physics theories, reactor physics calculation models and programs, and nuclear characteristics of new reactor types. Neutron flux density measurement is the foundation of reactor neutronics experiments, and in-reactor neutronics parameters are generally obtained through neutron flux density measurement.

[0003] The traditional method for online measurement of the relative distribution of neutron flux density is achieved through neutron detectors. A single detector is moved to different test locations for measurement, or multiple neutron detectors are arranged at multiple test locations to directly measure the electrical pulses of the neutron detectors, thereby providing the relative distribution of neutron flux density online. This method has the following drawbacks: (1) The size of the neutron detector is relatively large (several centimeters or even larger), requiring special channels. Its placement is greatly limited by the reactor space, and it can only be placed in a few locations. (2) The neutron detector causes significant disturbance to the neutron field inside the reactor. The detector and its encapsulated shell, cables, and other materials absorb and scatter neutrons, thereby changing the neutron flux density field to be measured.

[0004] The traditional method for offline measurement of the relative distribution of neutron flux density is achieved through an activation plate. A small activation plate is placed at the location to be measured inside the reactor. After irradiation inside the reactor for a certain period of time, the activation plate is removed from the reactor and placed in a detector such as high-purity germanium. The neutron flux density inside the reactor is calculated by measuring the intensity of gamma rays. This method has the following shortcomings: (1) The activation plate needs to be irradiated inside the reactor for a certain period of time, and it cannot measure the change of neutron flux density over time or provide the neutron flux density in real time. (2) The activation plate has a certain degree of radioactivity after irradiation, and it needs to be disposed of as radioactive waste in accordance with regulations, which increases costs and environmental burden. (3) The measurement process is relatively complicated and the cycle is long.

[0005] In summary, how to reduce disturbances to the neutron field within the reactor and how to quickly and easily monitor the neutron flux density and relative density in real time are research hotspots in this field. Summary of the Invention

[0006] The technical problem to be solved by this application is to address the above-mentioned deficiencies in the existing technology by providing a method and apparatus for measuring the relative distribution of neutron flux density, and a method and system for determining neutron parameters. Using this method for measuring the relative distribution of neutron flux density can reduce disturbances to the neutron field inside the reactor and enable rapid and convenient real-time monitoring of the relative distribution of neutron flux density inside the reactor.

[0007] In a first aspect, embodiments of this application provide a method for measuring the relative distribution of neutron flux density, wherein each of the M first optical fibers is arranged at the test position in its corresponding zero-power device core; each first optical fiber is filled with neutron-sensitive material; M is a positive integer; The method includes: Obtain the luminous intensity of the first optical fiber corresponding to each test location to obtain M luminous intensities; Based on the M emission intensities, determine the relative distribution of neutron flux density at each test location.

[0008] In some embodiments of the first aspect, determining the relative distribution of neutron flux density of the zero-power device based on M luminescence intensities includes: Substituting the M luminescence intensities into formula (1), the relative distribution of neutron flux density is calculated. Formula (1) includes: (1) in, Let represent the relative distribution of neutron flux density at the i-th test location, where i is a positive integer greater than or equal to 1 and less than or equal to M; This represents the light emission intensity of the first optical fiber at the i-th test position.

[0009] In some embodiments of the first aspect, the dimensions, structure and material composition of each first optical fiber are the same, and each first optical fiber includes a first segment filled with a neutron-sensitive material. The first volume, the microscopic cross section of the first neutron reaction, and the number of atoms per unit volume are all related to the total number of first optical fibers, the macroscopic cross section of the first neutron reaction, the second volume, and the first perturbation limit. The first volume is the volume of a single first segment. The microscopic cross section of the first neutron reaction is the microscopic cross section of the neutron reaction of the neutron-sensitive material in the first segment. The number of atoms per unit volume is the number of atoms per unit volume of the neutron-sensitive material in the first segment. The macroscopic cross section of the first neutron reaction is the macroscopic cross section of the neutron reaction in the core of the zero-power device. The second volume is the volume of the core of the zero-power device. The first perturbation limit is the perturbation limit of the first optical fiber on the neutron field inside the reactor.

[0010] In some embodiments of the first aspect, the first volume, the first neutron reaction microsection and the number of atoms per unit volume all satisfy formula (2). Formula (2) includes: (2) in, The first neutron reaction cross section is represented by N; N is the number of atoms per unit volume; V is the first volume. The macroscopic cross section of the first neutron reaction; For the second volume; This is the first disturbance limit.

[0011] In some embodiments of the first aspect, obtaining the luminous intensity of the first optical fiber corresponding to each test location includes: The luminous intensity of the first optical fiber at each test location is obtained using an optical power meter.

[0012] Based on the same inventive concept, in a second aspect, embodiments of this application provide a method for determining neutronics parameters, including: According to the neutron flux density relative distribution measurement method of any one of the first aspects, determine the neutron flux density relative distribution at each measurement location; Neutronics parameters within the reactor are determined based on the relative distribution of neutron flux density at each test location.

[0013] Based on the same inventive concept, in a third aspect, embodiments of this application provide a neutron flux density relative distribution measuring device, wherein each of the M first optical fibers is arranged at the test position of its corresponding zero-power device core; each first optical fiber is filled with neutron-sensitive material; M is a positive integer; The device includes: The first acquisition module is used to acquire the luminous intensity of the first optical fiber corresponding to each test position, so as to obtain M luminous intensities; The first determining module is used to determine the relative distribution of neutron flux density at each test location based on M emission intensities.

[0014] In some embodiments of the third aspect, the first determining module is specifically used for: Substituting the M luminescence intensities into formula (1), the relative distribution of neutron flux density is calculated. Formula (1) includes: (1) in, Let represent the relative distribution of neutron flux density at the i-th test location, where i is a positive integer greater than or equal to 1 and less than or equal to M; This represents the light emission intensity of the first optical fiber at the i-th test position.

[0015] In some embodiments of the third aspect, the dimensions, structure and material composition of each first optical fiber are the same, and each first optical fiber includes a first segment filled with a neutron-sensitive material. The first volume, the microscopic cross section of the first neutron reaction, and the number of atoms per unit volume are all related to the total number of first optical fibers, the macroscopic cross section of the first neutron reaction, the second volume, and the first perturbation limit. The first volume is the volume of a single first segment. The microscopic cross section of the first neutron reaction is the microscopic cross section of the neutron reaction of the neutron-sensitive material in the first segment. The number of atoms per unit volume is the number of atoms per unit volume of the neutron-sensitive material in the first segment. The macroscopic cross section of the first neutron reaction is the macroscopic cross section of the neutron reaction in the core of the zero-power device. The second volume is the volume of the core of the zero-power device. The first perturbation limit is the perturbation limit of the first optical fiber on the neutron field inside the reactor.

[0016] In some embodiments of the third aspect, the first volume, the first neutron reaction microsection, and the number of atoms per unit volume all satisfy formula (2). Formula (2) includes: (2) in, The first neutron reaction cross section is represented by N; N is the number of atoms per unit volume; V is the first volume. The macroscopic cross section of the first neutron reaction; For the second volume; This is the first disturbance limit.

[0017] In some embodiments of the third aspect, the first acquisition module is specifically used for: The luminous intensity of the first optical fiber at each test location is obtained using an optical power meter.

[0018] Based on the same inventive concept, in a fourth aspect, embodiments of this application also provide a neutronics parameter determination system, comprising: The neutron flux density relative distribution measuring device of any one of the third aspects is used to determine the neutron flux density relative distribution at each measurement location; The determination device is used to determine the neutronics parameters within the reactor based on the relative distribution of neutron flux density at each test location.

[0019] Based on the same inventive concept, in a fifth aspect, embodiments of this application provide an electronic device, the electronic device comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores one or more computer programs executable by the at least one processor, the one or more computer programs being executed by the at least one processor to enable the at least one processor to perform the above-described method for measuring the relative distribution of neutron flux density or the method for determining neutron parameters.

[0020] Based on the same inventive concept, in a sixth aspect, embodiments of this application provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the above-described method for measuring the relative distribution of neutron flux density or the method for determining neutron parameters.

[0021] Based on the same inventive concept, in a seventh aspect, embodiments of this application provide a computer program product, which includes computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code, wherein when the computer-readable code is run in the processor of an electronic device, the processor in the electronic device executes the above-described method for measuring the relative distribution of neutron flux density or the method for determining neutron parameters.

[0022] According to the neutron flux density relative distribution measurement method and apparatus, neutronics parameter determination method and system provided in the embodiments of this application, due to the extremely small size of the optical fiber, it can be flexibly arranged in the narrow space inside the zero-power device stack to achieve distributed measurement dimensions, reaching a spatial resolution at the centimeter level, and causing very little disturbance to the neutron field inside the stack; by using M luminescence intensities, the neutron flux density distribution inside the stack can be monitored quickly, easily and in real time.

[0023] In summary, the embodiments of this application can reduce disturbances to the neutron field within the reactor and can quickly and easily monitor the relative distribution of neutron flux density within the reactor in real time.

[0024] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this application, nor is it intended to limit the scope of this application. Other features of this application will become readily apparent from the following description. Attached Figure Description

[0025] The accompanying drawings are provided to further illustrate the present application and form part of the specification. They are used together with the embodiments of the present application to explain the application and do not constitute a limitation thereof. The above and other features and advantages will become more apparent to those skilled in the art from the detailed example embodiments described with reference to the accompanying drawings, in which: Figure 1 This illustration shows a structural schematic of a neutron flux density relative distribution measurement system provided in an embodiment of this application. Figure 2 This illustration shows a flowchart of a method for measuring the relative distribution of neutron flux density provided in an embodiment of this application. Figure 3 This is a schematic diagram showing the relative distribution of core axial thermal neutron flux density provided in an embodiment of this application; Figure 4 This is a schematic diagram of a neutron flux density relative distribution measuring device provided in an embodiment of this application; Figure 5 This illustration shows a structural diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0026] To enable those skilled in the art to better understand the technical solutions of this application, exemplary embodiments of this application are described below in conjunction with the accompanying drawings, including various details of the embodiments of this application to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. Similarly, for clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0027] Where there is no conflict, the various embodiments of this application and the features thereof may be combined with each other.

[0028] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0029] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application. As used herein, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded. Terms such as “connected” or “linked” are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0030] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this application, and will not be interpreted as having an idealized or overly formal meaning, unless expressly so defined herein.

[0031] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0032] Before introducing the neutron flux density relative distribution measurement method provided in the embodiments of this application, the neutron flux density relative distribution measurement system involved in the embodiments of this application will be described first.

[0033] like Figure 1 As shown, the neutron flux density relative distribution measurement system provided in this application embodiment includes a reactor core (i.e., a zero-power device reactor core), an optical switch, an optical power meter, and a computer.

[0034] M test sites are set on the reactor core. Each of the M first optical fibers (i.e., fibers containing neutron-sensitive material) is positioned at its corresponding test site in the zero-power device core; each first optical fiber is filled with neutron-sensitive material; M is a positive integer. This neutron-sensitive material reacts with neutrons to produce gamma rays of a specific wavelength. By acquiring the luminescence intensity within each first optical fiber, the relative distribution of neutron flux density within the reactor core can be obtained in real time.

[0035] It should be noted that the value of M can be set according to the actual situation, and is not limited here.

[0036] For example, the first optical fiber is connected to an optical switch via a radiation-resistant optical fiber, the optical switch is connected to an optical power meter via a radiation-resistant optical fiber, and the optical power meter is communicatively connected to a computer.

[0037] For example, an optical switch can switch different first optical fibers to an optical power meter.

[0038] For example, an optical power meter can measure the luminous intensity within a first optical fiber.

[0039] For example, a computer can execute the neutron flux density distribution measurement method provided in the embodiments of this application.

[0040] For example, the dimensions, structure and material composition of each first optical fiber are the same.

[0041] The neutron flux density relative distribution measurement method provided in this application is applicable to the process of determining neutron parameters within a reactor and during reactor monitoring. This neutron flux density relative distribution measurement method can be executed by a neutron flux density relative distribution measurement device, a computer, or electronic equipment. The following description uses the execution of this neutron flux density relative distribution measurement method by a computer as an example.

[0042] like Figure 2 As shown, the neutron flux density relative distribution measurement method provided in this application embodiment includes steps S110 to S120.

[0043] S110. Obtain the luminous intensity of the first optical fiber corresponding to each test position to obtain M luminous intensities.

[0044] S120. Based on the M emission intensities, determine the relative distribution of neutron flux density at each test location.

[0045] According to the neutron flux density relative distribution measurement method provided in the embodiments of this application, since the optical fiber is extremely small, it can be flexibly arranged in the narrow space inside the zero-power device stack to achieve distributed measurement dimensions and achieve spatial resolution at the centimeter level, and the disturbance to the neutron field inside the stack is very small; by using M luminescence intensities, the neutron flux density distribution inside the stack can be monitored quickly, easily and in real time.

[0046] The specific implementation methods for each of the above steps are described below.

[0047] In step S110, in some embodiments, the luminous intensity of the first optical fiber corresponding to each test location is obtained, including: The luminous intensity of the first optical fiber at each test location is obtained using an optical power meter.

[0048] Specifically, such as Figure 1 As shown, the computer is connected to the optical power meter. After the optical power meter measures the light intensity in each first optical fiber, it transmits the light intensity in the first optical fiber to the computer so that the computer can obtain the light intensity of the first optical fiber corresponding to each test position.

[0049] In step S120, in some embodiments, determining the relative distribution of neutron flux density of the zero-power device based on the M luminescence intensities includes: Substituting the M luminescence intensities into formula (1), the relative distribution of neutron flux density is calculated. Formula (1) includes: (1) in, Let represent the relative distribution of neutron flux density at the i-th test location, where i is a positive integer greater than or equal to 1 and less than or equal to M; This represents the light emission intensity of the first optical fiber at the i-th test position.

[0050] In this embodiment, the relative distribution of neutron flux density can be determined quickly and accurately using the above formula (1), thereby enabling rapid and convenient real-time monitoring of the relative distribution of neutron flux density within the reactor.

[0051] The principle behind the above formula (1) is explained below.

[0052] According to the principle of fiber optic light emission, neutrons undergo a nuclear reaction with the neutron-sensitive material inside the optical fiber, releasing energy to excite light emission. Therefore, the intensity of the light emission... Reaction rate with neutron nuclei R i It is directly proportional to the number of nuclear reactions per unit time.

[0053] The nuclear reaction rate R i =δ·N·V· Where δ·N is the probability of a nuclear reaction between the neutron-sensitive material within the optical fiber and one neutron, and V is the volume of the optical fiber's sensitive material. Since the material and dimensions of each segment of the optical fiber are the same, R... i Relative distribution with neutron flux density Proportional.

[0054] Therefore, luminous intensity Relative distribution with neutron flux density Proportional. Luminous intensity The relative distribution is the relative distribution of neutron flux density. The relative distribution of .

[0055] In some embodiments, the dimensions, structure and material composition of each first optical fiber are the same, and each first optical fiber includes a first segment filled with a neutron-sensitive material. The first volume, the microscopic cross section of the first neutron reaction, and the number of atoms per unit volume are all related to the total number of first optical fibers, the macroscopic cross section of the first neutron reaction, the second volume, and the first perturbation limit. The first volume is the volume of a single first segment. The microscopic cross section of the first neutron reaction is the microscopic cross section of the neutron reaction of the neutron-sensitive material in the first segment. The number of atoms per unit volume is the number of atoms per unit volume of the neutron-sensitive material in the first segment. The macroscopic cross section of the first neutron reaction is the macroscopic cross section of the neutron reaction in the core of the zero-power device. The second volume is the volume of the core of the zero-power device. The first perturbation limit is the perturbation limit of the first optical fiber on the neutron field inside the reactor.

[0056] For example, the microscopic cross section of the first neutron reaction represents the probability of a nuclear reaction between one neutron and one target nucleus.

[0057] For example, the macroscopic cross section of the first neutron reaction represents the average probability of a nuclear reaction between one neutron and all atomic nuclei within a unit volume. For instance, if the reactor core is entirely composed of graphite, the macroscopic cross section of the neutron reaction in graphite is 0.385 cm⁻¹. -1 .

[0058] For example, the first disturbance limit is 10. -5 .

[0059] In some examples, the first volume, the first neutron reaction microsection, and the number of atoms per unit volume all satisfy formula (2). Formula (2) includes: (2) in, The first neutron reaction cross section is represented by N; N is the number of atoms per unit volume; V is the first volume. The macroscopic cross section of the first neutron reaction; For the second volume; This is the first disturbance limit.

[0060] In this example, by using the above formula (2) to select the first optical fiber that meets the conditions, the disturbance of the first optical fiber to the neutron field in the reactor can be minimized.

[0061] For example, δ N represents the average probability of a nuclear reaction between one neutron and a unit volume of neutron-sensitive material within an optical fiber.

[0062] It should be noted that the purpose of the experiment is to measure the relative distribution of neutron flux density within the reactor (i.e., the neutron field within the reactor). As a neutral particle, neutrons can generally only be measured through nuclear reactions between neutrons and detector materials (i.e., neutron-sensitive materials). For example, boron neutron proportional counter tube detectors utilize the nuclear reaction between B10 and neutrons. However, after a neutron undergoes a nuclear reaction, it inevitably disturbs the neutron field within the reactor, meaning that the measured neutron field is not the original neutron field.

[0063] Compared to neutron detectors, which require specialized channels and have detector sizes on the order of several centimeters, optical fibers can have diameters on the order of hundreds of micrometers and do not require specialized large channels, thus causing relatively little disturbance to the neutron field within the reactor. However, the content of neutron-sensitive material within the optical fiber, as well as the size and quantity of the fiber, can also generate significant disturbances if they are excessive. Therefore, formula (2) quantitatively limits the disturbance of the neutron field by the optical fiber.

[0064] In formula (2), the numerator on the left side represents the probability of nuclear reaction between the optical fiber and neutrons, and the denominator represents the probability of nuclear reaction between the entire core and neutrons (the denominator represents the original neutron field of the core, and it is the various nuclear reactions between the core and neutrons that form the neutron distribution field).

[0065] To better understand the neutron flux density relative distribution measurement method provided in the embodiments of this application, the following description is provided in conjunction with specific implementation methods.

[0066] like Figure 1 As shown, optical fibers of the same size and material (i.e., the first optical fiber) are arranged simultaneously at the test location of the zero-power device core. The optical fibers are filled with neutron-sensitive material. After the neutron-sensitive material reacts with neutrons, it will generate γ-rays of a specific wavelength. By measuring the luminescence intensity in each optical fiber, the relative distribution of neutron flux density in the core (i.e., the relative distribution of neutron flux density) can be obtained in real time.

[0067] In this embodiment, the zero-power device core is composed of graphite block assemblies. The graphite blocks contain channels for loading fuel rods, and the core can be loaded with different numbers of fuel rods depending on experimental requirements. The neutron-sensitive materials are gadolinium (Gd) and terbium (Tb), meaning that Gd and Tb elements are doped into the glass fiber material in a ratio equal to natural nuclides. Gd reacts with neutrons within the reactor core, and the energy released from this reaction is deposited in the glass fiber matrix, causing Tb to be in an excited state. When Tb de-excites, it emits green light with a wavelength of approximately 540 nm.

[0068] Optical fiber consists of two segments: one containing neutron-sensitive material and the other not. The optical fiber containing neutron-sensitive material satisfies formula (2): (2) In formula (2), δ represents the microscopic cross-section of the neutron-sensitive material within the optical fiber, indicating the probability of a nuclear reaction between a neutron and a target nucleus. The thermal neutron cross-section of Gd is 49000 β (1 β = 10⁻⁶). -24 cm 2 ); N represents the number of atoms per unit volume of the neutron-sensitive material within the optical fiber; the atomic number density of Gd is 1 × 10⁻⁶. 20 pcs / cm 3 ;δ N represents the average probability of a nuclear reaction between one neutron and a unit volume of neutron-sensitive material within an optical fiber.

[0069] V represents the volume of a single neutron-sensitive material fiber segment, with a radial diameter of 500 μm and an axial length of 2 cm for a single fiber. M represents the number of fiber segments of the neutron-sensitive material, with 15 fiber segments arranged axially at one radial point. The cross-section of the neutron reaction in the reactor core represents the average probability of a neutron reacting with all atomic nuclei within a unit volume. The reactor core is entirely composed of graphite, and the macro-sectional area of ​​the neutron reaction in graphite is 0.385 cm⁻¹. The volume of the reactor core is 175cm in diameter and 150cm in length. The reactor core is a hexagonal prism with a radial distance between opposite sides of 175cm and an axial length of 150cm. ω is the perturbation limit of the fiber to the neutron field within the reactor; in this embodiment, it is taken as 10. -5 .

[0070] Calculations show that the above fiber optic arrangement has an impact of only 1.9 × 10⁻⁶ on the in-reactor neutron field. -7 It is far below the limit.

[0071] The relative distribution factor of neutron flux density at each measurement location is obtained by formula (1): (1) In formula (1), is the normalized relative distribution factor of neutron flux density at the i-th test location; Let be the light emission intensity inside the optical fiber at the i-th test location; M represents the number of fiber segments in the neutron-sensitive material, which, as mentioned above, is 15 segments.

[0072] Figure 3 It is the result of the relative distribution of axial thermal neutron flux density in the reactor core. Figure 3 The horizontal axis represents the axial coordinate, with units of centimeters (cm); the vertical axis represents the normalized neutron flux density factor (relative distribution of neutron flux density). A core model is constructed using the general Monte Carlo program RMC. The theoretical value of the thermal neutron flux density distribution can be calculated using the neutron flux counter in the RMC program. The material, dimensions, and arrangement of the optical fiber are modeled in detail using the RMC program. The luminous intensity within the fiber can be obtained by statistically analyzing the (n, γ) reactivity. Combined with formula (1), the measured value of the thermal neutron flux density distribution is obtained. Figure 3 It can be seen that the measured value of thermal neutron flux density distribution is in good agreement with the theoretical value, with a relative deviation within ±3%.

[0073] Furthermore, in the zero-power device neutron flux density relative distribution measurement method and system described above, the measurement system includes an optical fiber containing a neutron-sensitive material, a radiation-resistant optical fiber without a neutron-sensitive material, an optical switch, an optical power meter, and a computer. The optical switch can switch different optical fibers to the optical power meter, the optical power meter can measure the luminous intensity within the optical fiber, and the computer can process the luminous intensity data.

[0074] The beneficial effects of this application's embodiments are: the optical fiber is extremely small in size, allowing for flexible arrangement within the narrow space of the reactor core, enabling distributed measurement dimensions and achieving centimeter-level spatial resolution, while minimizing disturbance to the neutron field within the reactor core. Through the transmission of optical signals from radiation-resistant optical fibers and the measurement by an optical power meter, the neutron flux density distribution within the reactor core can be monitored quickly and easily in real time.

[0075] Based on the same inventive concept, in a second aspect, embodiments of this application provide a method for determining neutronics parameters. This method includes steps S210 to S220.

[0076] S210. Determine the relative distribution of neutron flux density at each location to be measured according to the neutron flux density relative distribution measurement method of the first aspect.

[0077] S220. Determine the neutronics parameters within the reactor based on the relative distribution of neutron flux density at each test location.

[0078] For example, neutronics parameters may include relative power distribution, etc. The relative power distribution can be obtained by converting the relative distribution of neutron flux density by power weight.

[0079] The neutron parameters determination method provided in this application includes a method for measuring the relative distribution of neutron flux density, which has the beneficial effects and implementation methods of the method for measuring the relative distribution of neutron flux density provided in this application. For details, please refer to the specific description of the method for measuring the relative distribution of neutron flux density in the above embodiments. This embodiment will not repeat the description here.

[0080] Based on the same inventive concept, in a third aspect, embodiments of this application also provide a device for measuring the relative distribution of neutron flux density. Each of the M first optical fibers is arranged at the measurement location in its corresponding zero-power device core; each first optical fiber is filled with a neutron-sensitive material; M is a positive integer. For example... Figure 4 As shown, the device includes a first acquisition module 310 and a first determination module 320.

[0081] The first acquisition module 310 is used to acquire the luminous intensity of the first optical fiber corresponding to each test position, so as to obtain M luminous intensities. The first determining module 320 is used to determine the relative distribution of neutron flux density at each test location based on M luminescence intensities.

[0082] According to the neutron flux density relative distribution measurement device provided in the embodiments of this application, due to the extremely small size of the optical fiber, it can be flexibly arranged in the narrow space inside the zero-power device stack to achieve distributed measurement dimensions, reaching a spatial resolution at the centimeter level, and causing very little disturbance to the neutron field inside the stack; by using M luminescence intensities, the neutron flux density distribution inside the stack can be monitored quickly and easily in real time.

[0083] In summary, the embodiments of this application can reduce disturbances to the neutron field within the reactor and can quickly and easily monitor the relative distribution of neutron flux density within the reactor in real time.

[0084] In some implementations, the first determining module 320 is specifically used for: Substituting the M luminescence intensities into formula (1), the relative distribution of neutron flux density is calculated. Formula (1) includes: (1) in, Let represent the relative distribution of neutron flux density at the i-th test location, where i is a positive integer greater than or equal to 1 and less than or equal to M; This represents the light emission intensity of the first optical fiber at the i-th test position.

[0085] In some embodiments, the dimensions, structure and material composition of each first optical fiber are the same, and each first optical fiber includes a first segment filled with a neutron-sensitive material. The first volume, the microscopic cross section of the first neutron reaction, and the number of atoms per unit volume are all related to the total number of first optical fibers, the macroscopic cross section of the first neutron reaction, the second volume, and the first perturbation limit. The first volume is the volume of a single first segment. The microscopic cross section of the first neutron reaction is the microscopic cross section of the neutron reaction of the neutron-sensitive material in the first segment. The number of atoms per unit volume is the number of atoms per unit volume of the neutron-sensitive material in the first segment. The macroscopic cross section of the first neutron reaction is the macroscopic cross section of the neutron reaction in the core of the zero-power device. The second volume is the volume of the core of the zero-power device. The first perturbation limit is the perturbation limit of the first optical fiber on the neutron field inside the reactor.

[0086] In some implementations, the first volume, the first neutron reaction microsection, and the number of atoms per unit volume all satisfy formula (2). Formula (2) includes: (2) in, The first neutron reaction cross section is represented by N; N is the number of atoms per unit volume; V is the first volume. The macroscopic cross section of the first neutron reaction; For the second volume; This is the first disturbance limit.

[0087] In some implementations, the first acquisition module 310 is specifically used for: The luminous intensity of the first optical fiber at each test location is obtained using an optical power meter.

[0088] The neutron flux density relative distribution measurement system provided in this application embodiment can be used to perform the neutron flux density relative distribution measurement method, that is, it has the beneficial effects and implementation methods of the neutron flux density relative distribution measurement method provided in this application embodiment. For details, please refer to the specific description of the neutron flux density relative distribution measurement method in the above embodiment, which will not be repeated here.

[0089] Based on the same inventive concept, in a fourth aspect, embodiments of this application also provide a neutronics parameter determination system, the system comprising: The neutron flux density relative distribution measuring device in the above embodiment is used to determine the relative distribution of neutron flux density at each measurement location; The determination device is used to determine the neutronics parameters within the reactor based on the relative distribution of neutron flux density at each test location.

[0090] The neutron parameter determination system provided in this application embodiment can be used to execute the neutron parameter determination method, that is, it has the beneficial effects and implementation methods of the neutron parameter determination method provided in this application embodiment. For details, please refer to the specific description of the neutron parameter determination method in the above embodiment, which will not be repeated here.

[0091] It is understood that the various method embodiments mentioned above in this application can be combined with each other to form combined embodiments without violating the principle and logic. Due to space limitations, this application will not elaborate further. Those skilled in the art will understand that in the above methods of specific implementation, the specific execution order of each step should be determined by its function and possible internal logic.

[0092] Figure 5 This is a block diagram of an electronic device provided in an embodiment of this application.

[0093] Reference Figure 5 This application provides an electronic device, which includes: at least one processor 701; at least one memory 702; and one or more I / O interfaces 703 connected between the processor 701 and the memory 702; wherein the memory 702 stores one or more computer programs that can be executed by the at least one processor 701, and the one or more computer programs are executed by the at least one processor 701 to enable the at least one processor 701 to perform the above-described method for measuring the relative distribution of neutron flux density or the method for determining neutron parameters.

[0094] This application also provides a computer-readable storage medium storing a computer program thereon, wherein the computer program, when executed by a processor / processing core, implements the aforementioned method for measuring the relative distribution of neutron flux density or the method for determining neutron parameters. The computer-readable storage medium may be volatile or non-volatile.

[0095] This application also provides a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code. When the computer-readable code is run in the processor of an electronic device, the processor in the electronic device executes the above-described method for measuring the relative distribution of neutron flux density or the method for determining neutron parameters.

[0096] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software can be distributed on a computer-readable storage medium, which may include computer storage media (or non-transitory media) and communication media (or transient media).

[0097] As is known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable program instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), flash memory or other memory technologies, portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable program instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0098] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0099] The computer program instructions used to perform the operations of this application may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuits, such as programmable logic circuits, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), are personalized by utilizing the status information of the computer-readable program instructions. These electronic circuits can execute the computer-readable program instructions to implement various aspects of this application.

[0100] The computer program product described herein can be implemented specifically through hardware, software, or a combination thereof. In one alternative embodiment, the computer program product is specifically embodied in a computer storage medium; in another alternative embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0101] Various aspects of this application are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0102] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0103] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0104] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0105] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for general illustrative purposes only and should not be construed as limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of this application as set forth by the appended claims.

Claims

1. A method for measuring the relative distribution of neutron flux density, characterized in that, Each of the M first optical fibers is arranged at the test position of its corresponding zero-power device core. Each of the first optical fibers is filled with a neutron-sensitive material; M is a positive integer; The method includes: The luminous intensity of the first optical fiber corresponding to each of the measured positions is obtained to obtain M luminous intensities; Based on the M luminescence intensities, determine the relative distribution of neutron flux density at each of the measured locations.

2. The method according to claim 1, characterized in that, Determining the relative distribution of neutron flux density of the zero-power device based on the M luminescence intensities includes: Substituting the M luminescence intensities into formula (1), the relative distribution of the neutron flux density is calculated. Formula (1) includes: （1） in, The relative distribution of the neutron flux density at the i-th measured location is represented, where i is a positive integer greater than or equal to 1 and less than or equal to M; The intensity of light emitted from the first optical fiber at the i-th position to be measured is represented.

3. The method according to claim 1, characterized in that, The dimensions, structure and material composition of each of the first optical fibers are the same, and each of the first optical fibers includes a first segment, which is filled with the neutron-sensitive material. The first volume, the first neutron reaction microscopic cross section, and the number of atoms per unit volume are all related to the total number of the first optical fibers, the first neutron reaction macroscopic cross section, the second volume, and the first disturbance limit; the first volume is the volume of a single first segment; the first neutron reaction microscopic cross section is the neutron reaction microscopic cross section of the neutron-sensitive material within the first segment; the first number of atoms per unit volume is the number of atoms per unit volume of the neutron-sensitive material within the first segment; the first neutron reaction macroscopic cross section is the neutron reaction macroscopic cross section of the zero-power device core; the second volume is the volume of the zero-power device core; the first disturbance limit is the disturbance limit of the first optical fiber to the neutron field within the reactor.

4. The method according to claim 3, characterized in that, The first volume, the first neutron reaction micro-section, and the number of atoms in the first unit volume all satisfy formula (2). Formula (2) includes: （2） in, The first neutron reaction cross section is represented by N; N is the number of atoms per unit volume; and V is the first volume. This is the macroscopic cross section of the first neutron reaction; This is the second volume; This is the first disturbance limit.

5. The method according to claim 1, characterized in that, The step of obtaining the luminous intensity of the first optical fiber corresponding to each of the measured positions includes: The luminous intensity of the first optical fiber corresponding to each of the test locations is obtained using an optical power meter.

6. A method for determining neutron parameters, characterized in that, include: The method for measuring the relative distribution of neutron flux density according to any one of claims 1 to 5 determines the relative distribution of neutron flux density at each measurement location; Neutronics parameters within the reactor are determined based on the relative distribution of neutron flux density at each test location.

7. A device for measuring the relative distribution of neutron flux density, characterized in that, Each of the M first optical fibers is arranged at the test position of its corresponding zero-power device core. Each of the first optical fibers is filled with a neutron-sensitive material; M is a positive integer; The device includes: The first acquisition module is used to acquire the luminous intensity of the first optical fiber corresponding to each of the test positions, so as to obtain M luminous intensities; The first determining module is used to determine the relative distribution of neutron flux density at each of the M emission intensities.

8. The apparatus according to claim 7, characterized in that, The first determining module is specifically used for: Substituting the M luminescence intensities into formula (1), the relative distribution of the neutron flux density is calculated. Formula (1) includes: （1） in, The relative distribution of the neutron flux density at the i-th measured location is represented, where i is a positive integer greater than or equal to 1 and less than or equal to M; The intensity of light emitted from the first optical fiber at the i-th position to be measured is represented.

9. The apparatus according to claim 7, characterized in that, The dimensions, structure and material composition of each of the first optical fibers are the same, and each of the first optical fibers includes a first segment, which is filled with the neutron-sensitive material. The first volume, the first neutron reaction microscopic cross section, and the number of atoms per unit volume are all related to the total number of the first optical fibers, the first neutron reaction macroscopic cross section, the second volume, and the first disturbance limit; the first volume is the volume of a single first segment; the first neutron reaction microscopic cross section is the neutron reaction microscopic cross section of the neutron-sensitive material within the first segment; the first number of atoms per unit volume is the number of atoms per unit volume of the neutron-sensitive material within the first segment; the first neutron reaction macroscopic cross section is the neutron reaction macroscopic cross section of the zero-power device core; the second volume is the volume of the zero-power device core; the first disturbance limit is the disturbance limit of the first optical fiber to the neutron field within the reactor.

10. A neutronics parameter determination system, characterized in that, include: The neutron flux density relative distribution measuring device according to any one of claims 7 to 9 is used to determine the relative distribution of neutron flux density at each measurement location; The determination device is used to determine the neutronics parameters within the reactor based on the relative distribution of neutron flux density at each test location.

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