Hyperspectral imaging-based liquid sodium leak detection system and method

Abstract

The application discloses a kind of liquid metal sodium leakage detection system and method based on hyperspectral imaging related to sodium cooling leakage technical field, the system is applied to sodium-cooled fast reactor in fourth generation advanced reactor, including optical module, imaging module and data processing module;Wherein, the imaging module is used to guide the radiation light of the leakage area of sodium-cooled fast reactor to the optical module;Optical module uses Offner optical structure, for the radiation light of the leakage area of sodium-cooled fast reactor is gathered and is handled with spectroscopy, obtains the hyperspectral image containing leakage area spatial information and spectral dimension information;The processing module is used to mark the characteristic spectral signal related to metal sodium in the hyperspectral image, and determines sodium leakage position based on the characteristic spectral signal marked.The system can realize the quick, accurate identification of liquid metal sodium leakage position in sodium-cooled fast reactor.

Description

Technical Field

[0001] This invention relates to the field of sodium cold leakage technology, and in particular to a liquid metallic sodium leakage detection system and method based on hyperspectral imaging. Background Technology

[0002] Sodium-cooled fast reactors, as one of the important representatives of fourth-generation advanced reactors, have become a key nuclear energy system researched and deployed by many countries around the world due to their excellent neutron economy and advantages in nuclear fuel breeding. A schematic diagram of a sodium-cooled fast reactor is shown below. Figure 1 As shown, the sodium-cooled fast reactor uses liquid metallic sodium as the main coolant and is a reactor in which nuclear fission, primarily induced by fast neutrons, sustains the chain reaction. Due to the high neutron travel speed in fast reactors, the ratio of the absorption interface to the fission interface is significantly reduced, and the number of neutrons produced per fission cycle is significantly increased. Therefore, fast reactors offer good neutron economy and possess thermal advantages such as high thermal conductivity, high boiling point, and operation at atmospheric pressure, effectively improving core cooling efficiency and system safety.

[0003] However, due to the high chemical reactivity of liquid sodium, it readily reacts with water vapor in the air at high temperatures. A leak could trigger a violent reaction or even an explosion, seriously threatening the safe operation of the reactor. Therefore, achieving efficient, accurate, and rapid detection of liquid sodium leaks has become one of the key technical challenges for the safe operation of sodium-cooled fast reactors.

[0004] In related technologies, the monitoring methods for sodium leaks mainly rely on indirect detection methods, such as using high-sensitivity hydrogen detectors. These methods infer the presence of a sodium leak by monitoring the concentration of hydrogen generated from the reaction of sodium with water vapor in the air. Although this method has been deployed in some engineering applications, its response mechanism depends on the detection of chemical reaction products, resulting in a slow overall response speed. Furthermore, the detection coverage of sensors is limited. To effectively monitor the entire cooling system, a large number of sensor nodes need to be deployed, leading to high system construction costs, complex maintenance, and a huge amount of data acquisition and analysis, increasing the system management burden. In actual operating conditions, due to the lag and coverage limitations of detection methods, it is often difficult to accurately locate the leak area in a timely manner, posing potential safety hazards. Summary of the Invention

[0005] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the objective of this invention is to propose a liquid sodium leakage detection system and method based on hyperspectral imaging, to achieve rapid and accurate identification of the location of liquid sodium leakage in a sodium-cooled fast reactor.

[0006] To achieve the above objectives, a first aspect of the present invention proposes a liquid sodium leakage detection system based on hyperspectral imaging, applicable to a sodium-cooled fast reactor in a fourth-generation advanced reactor. The system comprises an optical module, an imaging module, and a data processing module; wherein...

[0007] The imaging module is used to guide the radiation light from the leak area of ​​the sodium-cooled fast reactor to the optical module;

[0008] The optical module adopts the Offner optical structure to focus and disperse the radiation light from the leakage area of ​​the sodium-cooled fast reactor, and to obtain a hyperspectral image containing spatial and spectral information of the leakage area.

[0009] The processing module is used to annotate characteristic spectral signals related to metallic sodium in the hyperspectral image and determine the sodium leakage location based on the annotated characteristic spectral signals.

[0010] In addition, the liquid sodium leakage detection system based on hyperspectral imaging in the above embodiments of the present invention may also have the following additional technical features:

[0011] According to one embodiment of the present invention, the optical module includes a one-dimensional slit, a first concave spherical mirror, a convex spherical grating, a second concave spherical mirror, and a detector arranged sequentially; wherein,

[0012] The one-dimensional slit serves as the entrance for incident light to enter the optical module;

[0013] The first concave spherical mirror is used to collimate and reflect the incident light;

[0014] The convex spherical grating is used to disperse the aligned light.

[0015] The second concave spherical reflector is used to focus the split light onto the detector;

[0016] The detector is used to acquire the hyperspectral image.

[0017] According to one embodiment of the present invention, the first concave spherical reflector, the convex spherical grating and the second concave spherical reflector are symmetrically arranged about the optical center.

[0018] According to one embodiment of the present invention, the characteristic spectral signal includes at least sodium characteristic emission lines at 589 nm and 589.6 nm.

[0019] According to one embodiment of the present invention, the optical module is used to acquire image sequences with a wavelength range of 580-600nm.

[0020] According to one embodiment of the present invention, the resolution of the optical module is 0.01 nm.

[0021] According to one embodiment of the present invention, the imaging module includes a scanning mirror and an imaging lens;

[0022] The scanning mirror is positioned in front of the imaging lens and is used to scan the leakage area under the drive of the stepper motor.

[0023] The imaging lens is used to guide and focus the radiation light reflected by the scanning mirror onto the optical module.

[0024] According to one embodiment of the present invention, the stepper motor is interlocked and synchronized with the optical module, and the movement of the stepper motor is configured to be controlled by the data processing frequency of the optical module.

[0025] According to one embodiment of the present invention, the processing module is further configured to,

[0026] Based on the characteristic spectral signal and combined with an absolute quantitative model, the absolute concentration of sodium vapor generated by the leakage of liquid sodium in the leakage area is calibrated; the absolute quantitative model is established based on the experimental calibration results of standard sodium solution.

[0027] To achieve the above objectives, a second aspect of the present invention provides a method for detecting liquid sodium leakage based on hyperspectral imaging, the method comprising:

[0028] Acquire hyperspectral images of the leak area in the sodium-cooled fast reactor;

[0029] Extract characteristic spectral signals related to metallic sodium from the hyperspectral image;

[0030] The location of sodium leakage is determined based on the distribution of the characteristic spectral signal in the image space.

[0031] The liquid sodium leak detection system and method based on hyperspectral imaging of this invention accurately guides the radiation light from the leak area to the optical module through the imaging module, ensuring the integrity and stability of signal acquisition. The optical module adopts the Offner optical structure, which can achieve efficient beam focusing and high-resolution spectral separation, so that the obtained hyperspectral image contains both spatial and spectral information, which helps to improve the ability to identify leaked substances. The data processing module can automatically label the characteristic spectral signals related to liquid sodium leaks in the hyperspectral image and further accurately locate the leak location, thereby realizing rapid and non-contact detection of liquid sodium leaks, improving the sensitivity and safety of leak monitoring, and is particularly suitable for detecting refrigerant liquid sodium leaks in fourth-generation advanced reactors. Attached Figure Description

[0032] Figure 1A schematic diagram of a sodium-cooled fast reactor in a related technology;

[0033] Figure 2 This is a schematic diagram of a liquid sodium metal leakage detection system based on hyperspectral imaging in one embodiment;

[0034] Figure 3 This refers to the measurement range of a liquid sodium metal leak detection system in one embodiment;

[0035] Figure 4 This is a schematic diagram of the operation of an imaging module in one embodiment;

[0036] Figure 5 This is a schematic diagram of the optical module in one embodiment;

[0037] Figure 6 This is a schematic diagram of the atomic emission spectra of sodium in one embodiment, showing the D1 and D2 lines.

[0038] Figure 7 This is a flowchart illustrating a method for detecting liquid sodium leakage based on hyperspectral imaging in one embodiment. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0040] The implementation details of the technical solutions in the embodiments of this application are described in detail below.

[0041] like Figure 2 The diagram illustrates a hyperspectral imaging-based liquid sodium leak detection system. This system is applicable to sodium-cooled fast reactors (SNFRs) in Generation IV advanced reactors and is primarily used for real-time, non-contact remote detection of potential liquid sodium leaks during SNFR operation. In practical applications, this system employs hyperspectral imaging technology, combining the spatial resolution of images with the material identification capabilities of spectra. This enables effective early identification and location of leaking liquid sodium, making it particularly suitable for monitoring leaks of special media in high-risk environments such as nuclear power plants.

[0042] The following will describe in detail the specific structure and working principle of the liquid sodium leakage detection system based on hyperspectral imaging through different embodiments.

[0043] In one embodiment, a liquid sodium metal leak detection system based on hyperspectral imaging includes an imaging module, an optical module, and a data processing module.

[0044] The imaging module, through its strategically positioned location and angle, effectively guides the radiation emitted from the surfaces of objects or in aerosol form within the leak area of ​​the sodium-cooled fast reactor to the optical module. The leak area is a pre-defined spatial region where liquid sodium vapor from the sodium-cooled fast reactor may leak, typically corresponding to the area covered by the refrigerant circuit of the sodium-cooled fast reactor. For example... Figure 3 As shown in the figure, the measurement range of the liquid sodium leak detection system is the aforementioned leak area, where sodium vapor and other related substances generated by the leak may exist.

[0045] In one embodiment, the imaging module includes a scanning mirror and an imaging lens, wherein the scanning mirror is positioned in front of the imaging lens and is connected to a stepper motor to achieve progressive rotation control around a set axis. Figure 4 As shown, Figure 4 A schematic diagram of the imaging module's operation is shown. During operation, the imaging scanning range of the scanning mirror is as follows: Figure 4 As shown, driven by a stepper motor, the scanning mirror can actively scan the leak area, thus achieving global coverage of the leak area. It should be noted that this scanning structure is an active scanning architecture, capable of automatically imaging the leak area without the need for an external mechanical scanning platform, thus improving the system's integration and automation.

[0046] The scanning mirror guides radiated light from different angles and directions to the imaging lens. The imaging lens receives the radiated light reflected by the scanning mirror, spatially focuses it, and guides its path, ensuring accurate coupling of the radiated light into the optical module. The imaging lens not only performs the spatial focusing function of the radiated light but also achieves efficient optical path transmission, ensuring that the subsequent optical module can continuously acquire spectral information of the target area from different perspectives.

[0047] In one embodiment, a linkage control mechanism is established between the stepper motor in the imaging module and the optical module to achieve synchronous coordination between the imaging scanning action and the spectral data acquisition and processing. Specifically, the driving frequency of the stepper motor is coupled and matched with the data acquisition and processing frequency of the optical module. After the optical module completes the image acquisition and preliminary data processing for the current band, the stepper motor receives an interlock trigger signal and executes the next angular displacement, thereby driving the reflector to rotate slightly and enter the next imaging angle.

[0048] Through the aforementioned interlocking control method, the scanning motion of the reflector maintains a precise correspondence with the acquisition of hyperspectral images, ensuring temporal consistency and spatial continuity of the spectral images acquired at each scanning angle. This facilitates subsequent spectral reconstruction and multi-angle fusion analysis of the leak area. This linkage synchronization mechanism avoids data misalignment or image drift problems that may be introduced by traditional asynchronous scanning, improving the image stability and analysis accuracy of the detection system. It is suitable for dynamic tracking and refined identification scenarios of liquid sodium leaks.

[0049] The optical module employs the Offner optical structure to converge and disperse the radiated light from the leak area. During operation, the radiated light from the leak area is first guided by the imaging module before entering the optical module. The optical module converges the incoming radiated light to increase luminous flux; simultaneously, it uses dispersion techniques to spatially separate light components of different wavelengths, thereby forming hyperspectral data with a wavelength dimension in the two-dimensional image plane. Due to the excellent wavelength resolution and imaging consistency of the Offner structure, the optical module can maintain the integrity of the image's spatial information while ensuring that the radiated light at each spatial location in the leak area corresponds to a complete set of spectral information, thus generating a hyperspectral image containing both spatial and spectral dimensions.

[0050] It should be noted that hyperspectral images are a data format that carries both spatial distribution information and spectral response information. They can accurately reflect the geometric distribution characteristics of the leak area and the spectral absorption or radiation characteristics of the substances in that area, providing a rich data foundation for subsequent sodium leak identification.

[0051] In one embodiment, such as Figure 5 As shown, Figure 5 A schematic diagram of the optical module is shown, which includes a one-dimensional slit, a first concave spherical mirror, a convex spherical grating, a second concave spherical mirror, and a detector arranged sequentially.

[0052] The one-dimensional slit is set at the incident end face of the system to define the spatial resolution direction of the incident light, so that the subsequent optical path has a clear spatial distribution basis.

[0053] The first concave spherical mirror is installed in front of the exit end of the slit. Its curvature is designed to collimate the incident light beam exiting the slit into a parallel beam. The center of the mirror is aligned with the optical axis of the system to ensure that the collimated optical path is highly stable in space.

[0054] A convex spherical diffraction grating is positioned between the first and second concave mirrors as a dispersive element to separate incident multi-wavelength composite light at different angles. Figure 2In the diagram, different colors of light represent the propagation paths of different wavelength components, demonstrating the wavelength-selective diffraction effect of the grating. In practical applications, the curvature and position of the grating can be optimized according to the aberration correction design requirements of the Offner system.

[0055] The second concave spherical mirror is arranged after the diffraction grating and has a curvature structure symmetrical with the first mirror. The wavelength components of the beam after spectral dispersion are guided to the second concave spherical mirror. The second concave spherical mirror refocuses the multi-wavelength light after the grating dispersion and makes the spectral dispersion light form a clear two-dimensional hyperspectral image on the detector.

[0056] The detector can simultaneously record imaging information along both the spatial and spectral axes, thereby acquiring spatially resolved image data with continuous spectral dimensions. In practical applications, the detector can be an area array CMOS image sensor, with its working surface arranged on the confocal sphere of the optical module.

[0057] It should be noted that, in Figure 2 In this system, the detector can be further subdivided into a sampling region and a detector array. The light focused by the second concave spherical mirror forms a spectral image plane in the sampling region of the detector. The horizontal pixel axis corresponds to the one-dimensional spatial information of the measured region, while the vertical pixel axis corresponds to multiple wavelength channels after grating dispersion. Subsequently, the detector array obtains hyperspectral image data containing both spatial and spectral information by scanning and reading data line by line from this sampling region.

[0058] In actual assembly, all components in the optical module are mounted in a high-precision optical bracket and their positions are adjusted using a mechanical collimation process to ensure the coaxiality and symmetry of the entire Offner optical path, thereby significantly suppressing various system errors. Furthermore, this optical module works in conjunction with the scanning mirror in the imaging module. An external stepper motor controls the deflection of the scanning mirror, enabling the incident beam to perform a two-dimensional scan along the scene area, thus achieving line-by-line hyperspectral imaging of a large area.

[0059] In one embodiment, the optical module employs a symmetrical optical path design, wherein the first concave spherical mirror, the convex spherical diffraction grating, and the second concave spherical mirror are symmetrically arranged with respect to the optical central axis of the system, and the three share the same spherical center, forming a typical concentric optical structure, such as... Figure 5 As shown, its structural characteristics are embodied in Lr1 = Lr2. Under this concentric optical structure, aberrations in the optical path can be self-compensated, significantly improving imaging quality and spectral consistency. This structure enables high-resolution, high-efficiency spectral imaging without lenses, and is particularly suitable for accurately detecting the characteristic radiation generated during the leakage of liquid sodium.

[0060] In one embodiment, the system uses an imaging module and an optical module to perform continuous spectral detection on the leak area to identify the characteristic emission spectrum of sodium. The optical module has high-precision wavelength resolution capabilities, enabling it to distinguish and extract narrowband spectral information within the leak area.

[0061] To improve the accuracy of sodium leakage detection, the system specifically sets the target detection bands to include two wavelengths: 589 nm and 589.6 nm, corresponding to the characteristic emission spectra of sodium's D2 and D1 lines. When liquid sodium leaks and reacts with air or water, the excited-state sodium atoms produced will release spectral signals at these two wavelengths. The system's extraction and analysis of these characteristic signals can enable early identification and location of leakage events.

[0062] In one embodiment, to effectively cover the characteristic emission doublet of sodium and avoid interference from other background bands, the optical module is designed to acquire a narrowband image sequence with a wavelength range of 580 nm to 600 nm. This band not only encompasses the sodium spectral lines at 589 nm and 589.6 nm but also provides some upper and lower band redundancy for background subtraction and feature comparison. This band data is recorded channel-by-channel along the spectral dimension by a focal plane detector, forming a three-dimensional hyperspectral data cube. In the subsequent image processing module, the presence of sodium leakage is determined by the difference in characteristic wavelength response.

[0063] In one embodiment, to achieve high-precision spectral detection of sodium leakage, the optical module is configured with a spectral resolution of 0.01 nm. This resolution design is determined based on the emission spectral characteristics of liquid sodium and its spectral behavior during the leakage process.

[0064] Specifically, the leakage of liquid sodium metal will excite sodium atoms to produce characteristic emission spectra, including the D1 line (589.6 nm) and the D2 line (589 nm). Figure 6 This diagram shows a schematic of the atomic emission spectra of sodium along the D1 and D2 lines. Figure 6 In the analysis, these two spectral lines exhibit a significant difference in their full width at half maximum (FWHM). The FWHM of line D1 is 0.304 nm, while that of line D2 is 0.432 nm, with a difference of 0.128 nm. Therefore, to effectively distinguish the difference between the D1 and D2 spectral lines, an optical module resolution of 0.01 nm was selected to enhance the sensitivity and quantitative analysis capability of sodium leakage detection.

[0065] Furthermore, according to the energy level transition laws of sodium atoms, the amplified spontaneous emission signal intensity corresponding to the D2 line (589 nm) is significantly higher than that of the D1 line (589.6 nm). This is determined by the population inversion relation of excited states, i.e.

[0066] In the above formula, ΔN represents the number of inverted particles, Nu and Nl represent the number of excited and ground state particles, respectively, and gu and gl represent the energy level degeneracy. The sodium atom has a charge Z = 11 and a ground state electron configuration of 3s. Its double yellow line emission spectrum is due to a fine-structure split in the excited state 3p energy level, splitting into two energy levels, denoted as 3p... 3 / 2 With 3p 1 / 2 These two energy levels produce two characteristic spectral lines when they transition to the 3s ground state.

[0067] Based on the above analysis of spectral width, transition energy levels, and signal intensity differences, the optical module selected the visible light range as the spectral imaging interval and achieved a resolution of 0.01 nm through hyperspectral design. Within the optical module, a high-density concave spherical grating is used as the dispersive element, combined with a long focal length optical path design and a high-pixel area array detector, ensuring that the sampling interval of a single spectral channel is controlled within 0.01 nm. This configuration not only clearly distinguishes the 589 nm and 589.6 nm sodium spectral lines but also effectively extracts microscopic changes in spectral line shape, full width at half maximum (FWHM), and other indicators, improving the sensitivity and accuracy of sodium leak detection.

[0068] The processing module in the detection system is used to analyze and process the image data acquired by the hyperspectral image acquisition module to identify the unique spectral characteristics of liquid sodium leakage and determine the location of the leakage accordingly.

[0069] During the operation of the detection system, when liquid sodium leaks, the leak area generates a radiation signal containing characteristic emission lines of sodium. The imaging and optical modules scan and image the leak area, transmitting the acquired hyperspectral image data to the processing module. In the generated hyperspectral image, each pixel not only records its two-dimensional spatial location but also contains complete spectral information for that pixel, similar to a spectral fingerprint.

[0070] Since each substance possesses unique spectral response characteristics within a specific wavelength band, its spectral information can be considered a fingerprint for identification, exhibiting high uniqueness and distinguishability. Liquid sodium, in a leaking state, releases a typical spectral emission signal, particularly with distinct spectral peaks near 589 nm and 589.6 nm wavelengths. Therefore, the characteristic spectral information of sodium can be pre-labeled experimentally to form a standard spectral template for matching and identification.

[0071] After receiving the hyperspectral image data, the processing module analyzes the corresponding spectral curve pixel by pixel and compares it with the pre-labeled characteristic spectra of sodium. When a pixel exhibits significant spectral enhancement within the target wavelength range (e.g., 580nm to 600nm) and its spectral shape matches the standard template well, it can be determined that liquid metallic sodium is present at that pixel. Subsequently, the processing module can label the identified characteristic spectral pixels on the two-dimensional image, thereby visualizing the location of sodium leakage in the image.

[0072] In one embodiment, the processing module is further configured to calibrate the absolute concentration of sodium vapor generated by the leakage of liquid sodium in the leakage area based on the characteristic spectral signal and in conjunction with an absolute quantitative model. Specifically, after acquiring a hyperspectral image of the leakage area, the processing module can separate the characteristic spectral signal from the hyperspectral image through spectral extraction and feature recognition.

[0073] To achieve quantitative calculation of sodium vapor concentration, an absolute quantitative model was pre-established. This model was obtained through experimental calibration, specifically by using a series of standard sodium solutions of known concentrations to evaporate sodium vapor under controlled conditions, and then using the hyperspectral imaging module to obtain the corresponding characteristic spectral intensity values. By fitting the mapping relationship between the characteristic spectral intensity and the actual concentration, a quantitative model function was constructed.

[0074] In actual operation, the processing module invokes the absolute quantitative model, inputting the currently detected sodium characteristic spectral intensity value into the model to calculate the absolute concentration of sodium vapor in the leak area. This concentration value provides a quantitative basis for subsequent leak severity assessment and safety response strategies.

[0075] The hyperspectral imaging-based liquid sodium leak detection system described in the above embodiments, designed for the practical needs of fourth-generation advanced sodium-cooled fast reactors, integrates spectral analysis and spatial imaging technologies to construct a complete detection system comprising an integrated imaging module, an optical module, and a data processing module. The imaging and optical modules employ a non-contact measurement method to acquire hyperspectral images, avoiding physical interference with the sodium-cooled reactor equipment and ensuring the safety and integrity of the detection process. This not only achieves comprehensive and detailed capture of the leak area but also ensures high resolution and accuracy of the data. The data processing module intelligently analyzes the acquired hyperspectral images, accurately locating and identifying the sodium leak point by labeling the characteristic spectral signals of metallic sodium. The overall system, by combining the advantages of spectral analysis and spatial imaging, can simultaneously acquire two-dimensional spatial information and continuous spectral information, possessing real-time performance, high sensitivity, and high spatial resolution, enabling highly sensitive real-time monitoring of sodium vapor leaks.

[0076] In one embodiment, such as Figure 7 As shown, Figure 7A schematic flowchart of a method for detecting liquid sodium leakage based on hyperspectral imaging is shown, which may include the following steps:

[0077] Step S101: Acquire hyperspectral images of the leakage area of ​​the sodium-cooled fast reactor.

[0078] The leak area is a pre-defined spatial range within which liquid sodium vapor from a sodium-cooled fast reactor (SNCR) may leak, typically corresponding to the area covered by the SNCR refrigerant loop. To achieve comprehensive monitoring of this area, a non-contact scanning method is used, employing an imaging module to scan the leak area. This is combined with optical module processing to perform spectral dispersion and image focusing, ultimately obtaining hyperspectral image data containing both spatial and spectral information. The hyperspectral image is a three-dimensional data cube, containing a two-dimensional spatial dimension and a one-dimensional continuous spectral dimension, capable of fully reflecting the spectral characteristics of the radiation spectrum at various spatial locations within the target area.

[0079] Step S102: Extract the characteristic spectral signals related to metallic sodium from the hyperspectral image.

[0080] When metallic sodium leaks, it readily reacts with oxygen or moisture in the air to generate sodium atoms in a high-temperature excited state. These excited sodium atoms emit spectral signals of specific wavelengths during the transition process, especially the two typical sodium emission lines at 589.0 nm (D2 line) and 589.6 nm (D1 line).

[0081] Based on this characteristic, spectral analysis can be performed on the acquired hyperspectral images to extract characteristic spectral signals related to metallic sodium, particularly those with significant responses at the two key wavelengths of 589.0 nm and 589.6 nm. In practical processing, band selection, spectral noise reduction, spectral calibration, and feature matching algorithms can be combined to extract pixels with typical sodium emission peaks in the image, thereby obtaining characteristic spectral signals directly related to metallic sodium leakage.

[0082] Step S103: Determine the location of sodium leakage based on the distribution of characteristic spectral signals in the image space.

[0083] Since each pixel in a hyperspectral image contains complete spectral information for its corresponding spatial location, the extracted sodium feature spectral lines can be directly mapped to a specific pixel in the image space. Furthermore, by marking the locations of all pixels with characteristic spectral signals on the image, a labeled image can be formed, indicating the spatial distribution area of ​​sodium. These pixels with characteristic emission spectra are considered potential areas of sodium vapor presence, thereby determining the approximate location and distribution range of the leak source, achieving visualized detection and identification of liquid sodium leak locations.

[0084] The hyperspectral imaging-based liquid sodium leakage detection method described in the above embodiments enables comprehensive monitoring of potential leakage areas without contact with the equipment itself by acquiring hyperspectral images of the leakage area in a sodium-cooled fast reactor. This method extracts characteristic spectral signals related to metallic sodium from the images and analyzes their distribution patterns in the image space, thereby accurately identifying and locating the sodium leakage site. This method possesses stronger component identification and spatial resolution capabilities, effectively distinguishing liquid metallic sodium from other background interference substances and achieving higher-precision leakage location. Therefore, this detection method can significantly improve the fault detection capability and safety response speed during the operation of a sodium-cooled fast reactor.

[0085] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0086] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0087] In the description of this specification, 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 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.

[0088] 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.

[0089] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A liquid sodium metal leakage detection system based on hyperspectral imaging, characterized in that, The sodium-cooled fast reactor, used in fourth-generation advanced reactors, includes a hyperspectral imaging-based liquid sodium leakage detection system comprising an optical module, an imaging module, and a data processing module; wherein, The imaging module is used to guide the radiation light from the leak area of ​​the sodium-cooled fast reactor to the optical module; The optical module adopts the Offner optical structure to focus and disperse the radiation light from the leakage area of ​​the sodium-cooled fast reactor, and to obtain a hyperspectral image containing spatial and spectral information of the leakage area. The processing module is used to annotate characteristic spectral signals related to metallic sodium in the hyperspectral image and determine the sodium leakage location based on the annotated characteristic spectral signals.

2. The liquid sodium leakage detection system based on hyperspectral imaging according to claim 1, characterized in that, The optical module includes a one-dimensional slit, a first concave spherical mirror, a convex spherical grating, a second concave spherical mirror, and a detector, arranged sequentially; wherein... The one-dimensional slit serves as the entrance for incident light to enter the optical module; The first concave spherical mirror is used to collimate and reflect the incident light; The convex spherical grating is used to disperse the aligned light. The second concave spherical reflector is used to focus the split light onto the detector; The detector is used to acquire the hyperspectral image.

3. The liquid sodium leakage detection system based on hyperspectral imaging according to claim 2, characterized in that, The first concave spherical mirror, the convex spherical grating, and the second concave spherical mirror are symmetrically arranged about the optical center.

4. The liquid sodium leakage detection system based on hyperspectral imaging according to claim 1, characterized in that, The characteristic spectral signal includes at least the characteristic emission lines of sodium at 589 nm and 589.6 nm.

5. The liquid sodium leakage detection system based on hyperspectral imaging according to claim 4, characterized in that, The optical module is used to acquire image sequences with a wavelength range of 580-600nm.

6. The liquid sodium leakage detection system based on hyperspectral imaging according to claim 4, characterized in that, The optical module has a resolution of 0.01 nm.

7. The liquid sodium leakage detection system based on hyperspectral imaging according to claim 1, characterized in that, The imaging module includes a scanning mirror and an imaging lens; The scanning mirror is positioned in front of the imaging lens and is used to scan the leakage area under the drive of the stepper motor. The imaging lens is used to guide and focus the radiation light reflected by the scanning mirror onto the optical module.

8. The liquid sodium leakage detection system based on hyperspectral imaging according to claim 7, characterized in that, The stepper motor is interlocked and synchronized with the optical module, and the movement of the stepper motor is configured to be controlled by the data processing frequency of the optical module.

9. The liquid sodium leakage detection system based on hyperspectral imaging according to claim 1, characterized in that, The processing module is also used for, Based on the characteristic spectral signal and combined with the absolute quantitative model, the absolute concentration of sodium vapor generated by the leakage of liquid sodium in the leakage area is calibrated; the absolute quantitative model is established based on the experimental calibration results of standard sodium solution.

10. A method for detecting liquid sodium leakage based on hyperspectral imaging, characterized in that, The method, applied to the hyperspectral imaging-based liquid sodium leakage detection system according to any one of claims 1 to 9, comprises: Acquire hyperspectral images of the leak area in the sodium-cooled fast reactor; Extract characteristic spectral signals related to metallic sodium from the hyperspectral image; The location of sodium leakage is determined based on the distribution of the characteristic spectral signal in the image space.

Images