Full-size fuel assembly simulation body multifunctional test verification device and verification method thereof

Abstract

The invention discloses a full-size fuel assembly simulation body multifunctional test verification device and a verification method thereof, and the device comprises a plurality of grillwork simulation parts and a pipe body simulation mechanism. According to the multifunctional test verification device for the full-size fuel assembly simulation body, a basic simulation tube base body is arranged to simulate a field basic fuel rod, and an outer layer oxidation film simulation tube assembly is arranged to provide a test function for an outer layer oxidation film measurement device; the inner layer oxidation film simulation pipe assembly is used for providing a testing function for the inner layer oxidation film measuring device, the rod diameter testing simulation pipe assembly is used for providing a testing function for the rod diameter measuring device, and the damage testing simulation pipe base body is used for simulating the damage condition of the fuel rod. And the video test simulation tube base body is arranged to provide a test function for the video detection device, so that a comprehensive and effective detection function can be provided for the fuel assembly inspection system, and the consistency of a detection environment and an actual use environment is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear power plant fuel assembly detection, and particularly to a multifunctional test and verification device for a full-size fuel assembly simulation body and a verification method thereof. Background Art

[0002] During the operation of a nuclear power plant, it is necessary to regularly conduct in-pool inspections on fuel assemblies to ensure their safety and reliability. Currently, before the in-pool inspection equipment for fuel assemblies is put into on-site use, a large amount of test and verification work needs to be carried out. However, due to the lack of a simulation body that is exactly the same as the actual fuel assembly in terms of structural dimensions, it is difficult to effectively carry out the equipment test and verification work, and the test steps and methods are not representative. In particular, there are great difficulties in precision inspections such as electromagnetic detection, visual detection, and high-precision sensor testing.

[0003] Existing test devices mostly simulate local structures and cannot reflect the actual characteristics of full-size fuel assemblies. There are deviations between the device dimensions and the actual fuel assemblies, affecting the accuracy of test results. The function modules of local simulation components are single, unable to meet diverse test requirements, lacking comprehensive test capabilities. Different types of tests require the use of different devices, increasing the test cost and time.

[0004] The existing means for testing and verifying fuel assemblies mainly rely on the use of local simulation components. However, this method has the following technical problems:

[0005] 1. The structure of the test and verification device is inconsistent with the actual fuel assembly dimensions: Existing test devices mostly simulate local structures and cannot reflect the actual whole process of detecting full-size fuel assemblies, resulting in the inability to effectively identify and solve problems such as structural interference and equipment cable joint obstruction that may occur during the detection process. There are deviations between the device dimensions and the actual fuel assemblies, and displacement errors are generated in the detection probe module, affecting the accuracy of test results. The material properties do not match those of the actual fuel assemblies, resulting in distorted test results such as electromagnetic detection.

[0006] 2. The function modules are single and cannot meet diverse test requirements: Existing devices are often designed for a single test function and lack comprehensive test capabilities. Different types of tests require the use of different devices, increasing the test cost and time. There is a lack of compatibility between test modules, making it difficult to conduct systematic tests at one time. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a multifunctional test and verification device for a full-size fuel assembly simulation body and a verification method thereof.

[0008] The technical solution adopted by the present invention to solve its technical problems is: to construct a multifunctional test and verification device for a full-size fuel assembly simulator, which is used to provide test functions for a fuel assembly inspection system. The fuel assembly inspection system includes an outer oxide film measuring device, an inner oxide film measuring device, a rod diameter measuring device, and a video detection device. The multifunctional test and verification device for the full-size fuel assembly simulator includes a plurality of grid simulator parts and a tube body simulation mechanism;

[0009] The plurality of grid simulator parts are arranged separately in the height direction, and the tube body simulation mechanism is installed on the plurality of grid simulator parts;

[0010] The tube body simulation mechanism includes a plurality of basic simulation tube bases, at least one outer oxide film simulation tube assembly, at least one inner oxide film simulation tube assembly, at least one rod diameter test simulation tube assembly, at least one breakage test simulation tube base, and at least one video test simulation tube base;

[0011] The basic simulation tube base is used to simulate the on-site basic fuel rod;

[0012] The outer oxide film simulation tube assembly is used to provide test functions for the outer oxide film measuring device;

[0013] The inner oxide film simulation tube assembly is used to provide test functions for the inner oxide film measuring device;

[0014] The rod diameter test simulation tube assembly is used to provide test functions for the rod diameter measuring device;

[0015] The breakage test simulation tube base is used to simulate the situation of fuel rod breakage;

[0016] The video test simulation tube base is used to provide test functions for the video detection device.

[0017] In some embodiments, the outer oxide film simulation tube assembly is installed on the outermost side of the grid simulator part;

[0018] The outer oxide film simulation tube assembly includes an outer simulation upper base, an outer simulation upper fixing part, an outer oxide film calibration part, an outer simulation lower fixing part, and an outer simulation lower base that are sequentially connected in the axial direction;

[0019] The outer oxide film calibration part straddles one of the grid simulator parts.

[0020] In some embodiments, the inner oxide film simulation tube assembly is installed on the inner side of the grid simulator part;

[0021] The inner layer oxide film simulation tube assembly includes an upper inner layer simulation matrix, an upper inner layer simulation fixing part, an inner layer oxide film calibration part, a lower inner layer simulation fixing part, and a lower inner layer simulation matrix, which are sequentially connected in the axial direction;

[0022] The inner layer oxide film calibration part is arranged between adjacent grid frame simulation parts.

[0023] In some embodiments, the rod diameter test simulation tube assembly includes a plurality of rod diameter measurement quick-release parts, a plurality of rod diameter measurement calibration blocks, and a plurality of rod diameter measurement matrices;

[0024] Each rod diameter measurement matrix and each rod diameter measurement calibration block are connected through the rod diameter measurement quick-release part;

[0025] The plurality of rod diameter measurement calibration blocks are solid rods with different diameters.

[0026] In some embodiments, the damaged test simulation tube matrix is provided with water seepage holes.

[0027] In some embodiments, at least one of the grid frame simulation parts is provided with a first groove, and the video test simulation tube matrix is provided with a second groove.

[0028] In some embodiments, the full-size fuel assembly simulation body multi-functional test verification device further includes an upper tube seat simulation body and a lower tube seat simulation body, and a plurality of grid frame simulation parts and a tube body simulation mechanism are installed between the upper tube seat simulation body and the lower tube seat simulation body.

[0029] In this embodiment, a verification method for the full-size fuel assembly simulation body multi-functional test verification device is also constructed. Based on the full-size fuel assembly simulation body multi-functional test verification device, it includes the steps:

[0030] S1. Install the basic simulation tube matrix, the outer layer oxide film simulation tube assembly, the inner layer oxide film simulation tube assembly, the rod diameter test simulation tube assembly, and the damaged test simulation tube matrix on a plurality of grid frame simulation parts;

[0031] S2. Use an outer layer oxide film measuring device to measure the thickness of the outer layer oxide film of the outer layer oxide film calibration part of the outer layer oxide film simulation tube assembly;

[0032] S3. Use an inner layer oxide film measuring device to measure the thickness of the inner layer oxide film of the inner layer oxide film calibration part of the inner layer oxide film simulation tube assembly;

[0033] S4. Use a rod diameter measuring device to measure the rod diameters of the plurality of rod diameter measurement calibration blocks of the rod diameter test simulation tube assembly;

[0034] S5. Machine a first groove on one of the grid simulator components, machine a second groove on the video test simulation tube substrate, and use a video detection device to perform video detection on the first groove and the second groove;

[0035] S6. Make water seep in through the water seepage holes on the damaged test simulation tube substrate to simulate the situation of fuel rod damage.

[0036] In some embodiments, during the process of installing the outer oxide film simulation tube assembly on the grid simulator component, first install an outer oxide film sacrificial component with the same shape as the outer oxide film calibration component, and replace the outer oxide film sacrificial component with the outer oxide film calibration component after the pulling rod process of the outer oxide film simulation tube assembly;

[0037] During the process of installing the inner oxide film simulation tube assembly on the grid simulator component, first install an inner oxide film sacrificial component with the same shape as the inner oxide film calibration component, and replace the inner oxide film sacrificial component with the inner oxide film calibration component after the pulling rod process of the inner oxide film simulation tube assembly;

[0038] During the process of installing the rod diameter test simulation tube assembly on the grid simulator component, first install a rod diameter measurement sacrificial component with the same shape as the rod diameter measurement calibration block, and replace the rod diameter measurement sacrificial component with the rod diameter measurement calibration block after the pulling rod process of the rod diameter test simulation tube assembly.

[0039] In some embodiments, in step S5, machine a first groove on the grid simulator component by means of artificial electric spark or laser grooving;

[0040] Machine a second groove on the video test simulation tube substrate by means of artificial electric spark or laser grooving.

[0041] Implementing the present invention has the following beneficial effects: The full-size fuel assembly simulator multi-functional test and verification device simulates on-site basic fuel rods through the set basic simulation tube matrix, sets the outer oxide film simulation tube assembly to provide test functions for the outer oxide film measuring device, sets the inner oxide film simulation tube assembly to provide test functions for the inner oxide film measuring device, sets the rod diameter test simulation tube assembly to provide test functions for the rod diameter measuring device, sets the damaged test simulation tube matrix to simulate the situation of fuel rod damage, and sets the video test simulation tube matrix to provide test functions for the video detection device. By integrating multiple functions such as oxide film detection, rod diameter measurement detection, damage detection, and video detection, the full-size fuel assembly simulator multi-functional test and verification device can provide comprehensive and effective detection functions for the fuel assembly inspection system, ensure the consistency between the detection environment and the actual use environment, thereby improving the reliability of the detection results, and being more accurate and efficient for verifying the usability of the fuel assembly inspection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the present invention, the present invention will be further described below in conjunction with the drawings and embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings. In the drawings:

[0043] Figure 1 is the overall structural schematic diagram of the full-size fuel assembly simulator multi-functional test and verification device in some embodiments of the present invention;

[0044] Figure 2 is Figure 1 the enlarged schematic diagram at A in

[0045] Figure 3 is Figure 1 the enlarged schematic diagram at B in

[0046] Figure 4 is the structural schematic diagram of the inner oxide film simulation tube assembly in some embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0047] For a clearer understanding of the technical features, objectives, and effects of the present invention, the specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In the following description, it should be understood that the orientation or positional relationships indicated by "front", "rear", "upper", "lower", "left", "right", "longitudinal", "transverse", "vertical", "horizontal", "top", "bottom", "inner", "outer", "head", "tail", etc. are based on the orientation or positional relationships shown in the drawings, with a specific orientation structure and operation, and are only for the convenience of describing the present technical solution, rather than indicating that the device or element referred to must have a specific orientation. Therefore, it should not be construed as a limitation to the present invention.

[0048] It should also be noted that, unless otherwise clearly specified and limited, terms such as "installation", "connection", "attachment", "fixation", "setting" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between two elements. When an element is referred to as being "on" or "under" another element, the element can be "directly" or "indirectly" located above the other element, or there may also be one or more intermediate elements. The terms "first", "second", "third", etc. are only for the convenience of describing the present technical solution and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", "third", etc. can explicitly or implicitly include one or more of such features. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] Please refer to Figures 1 to 4 , which is a multifunctional test and verification device for a full-size fuel assembly simulator in some embodiments of the present invention, used to provide test functions for a fuel assembly inspection system. The fuel assembly inspection system includes an outer oxide film measurement device, an inner oxide film measurement device, a rod diameter measurement device, and a video detection device. The multifunctional test and verification device for a full-size fuel assembly simulator includes a plurality of grid simulator members 1 and a tube body simulation mechanism 2. The plurality of grid simulator members 1 are arranged at intervals in the height direction, and the tube body simulation mechanism 2 is installed on the plurality of grid simulator members 1. The tube body simulation mechanism 2 includes a plurality of basic simulation tube substrates 21, at least one outer oxide film simulation tube assembly 22, at least one inner oxide film simulation tube assembly 23, at least one rod diameter test simulation tube assembly 24, at least one damaged test simulation tube substrate 25, and at least one video test simulation tube substrate 26.

[0050] The basic simulation tube base 21 is used to simulate the on-site basic fuel rod; the outer oxide film simulation tube assembly 22 is used to provide a test function for the outer oxide film measuring device; the inner oxide film simulation tube assembly 23 is used to provide a test function for the inner oxide film measuring device; the rod diameter test simulation tube assembly 24 is used to provide a test function for the rod diameter measuring device; the breakage test simulation tube base 25 is used to simulate the breakage of the fuel rod; the video test simulation tube base 26 is used to provide a test function for the video detection device.

[0051] Among them, both the outer oxide film measuring device and the inner oxide film measuring device are electromagnetic detection devices. The outer oxide film measuring device and the inner oxide film measuring device can measure the oxide film using an eddy current sensor. The principle of the eddy current sensor is based on Faraday's law of electromagnetic induction, and various parameters are measured by detecting the eddy current in a metal conductor. When the sensor probe approaches the metal conductor, the alternating current in the probe generates an alternating magnetic field. This magnetic field induces an eddy current in the metal conductor, and the eddy current generates a reverse magnetic field, affecting the intensity of the original magnetic field. The measurement of the oxide film thickness utilizes the principle of electromagnetic induction of eddy currents. When a changing electromagnetic field acts near a conductor, an eddy current is generated in the conductor, and the magnitude of the eddy current changes with the distance between the changing electromagnetic field and the conductor. An eddy current sensor is used to detect the thickness of the oxide film. During measurement, the vertical component is selected as the measurement component. The oxide film measurement calibration block is used to calibrate the measurement curve of the oxide film measurement system, establishing the corresponding relationship between the vertical component of the eddy current signal and the oxide film thickness. After the reference is established, the thickness of the oxide film is measured, and the calibration is to make a corresponding relationship curve between the vertical component of the eddy current signal and the oxide film thickness.

[0052] Specifically, the basic simulation tube base 21, the outer oxide film simulation tube assembly 22, the inner oxide film simulation tube assembly 23, the rod diameter test simulation tube assembly 24, the breakage test simulation tube base 25, and the video test simulation tube base 26 are all installed on a plurality of grid simulation members 1. In this embodiment, the full-size fuel assembly simulation body multi-functional test and verification device uses a 12-foot full-size assembly, adopts a 17×17 square structure, the number of the grid simulation members 1 is 10, and the full-size fuel assembly simulation body multi-functional test and verification device further includes an upper tube seat simulation body 3 and a lower tube seat simulation body 4. A plurality of grid simulation members 1 and the tube body simulation mechanism 2 are all installed between the upper tube seat simulation body 3 and the lower tube seat simulation body 4. The tube body simulation mechanism 2 includes 265 simulated fuel rods and 24 guide tubes. In this embodiment, the number of the outer oxide film simulation tube assemblies 22 is 5, the number of the inner oxide film simulation tube assemblies 23 is 1, the number of the rod diameter test simulation tube assemblies 24 is 2, the number of the breakage test simulation tube bases 25 is 2, and the number of the video test simulation tube bases 26 is 1. The number of the above components can be adjusted according to the actual situation, and no specific limitation is made here.

[0053] Understandably, this full-scale fuel assembly simulation body multi-functional test and verification device simulates the on-site basic fuel rods by setting up the basic simulation tube matrix 21, sets up the outer oxide film simulation tube assembly 22 to provide test functions for the outer oxide film measuring device, sets up the inner oxide film simulation tube assembly 23 to provide test functions for the inner oxide film measuring device, sets up the rod diameter test simulation tube assembly 24 to provide test functions for the rod diameter measuring device, sets up the damaged test simulation tube matrix 25 to simulate the situation of fuel rod damage, and sets up the video test simulation tube matrix 26 to provide test functions for the video detection device. By integrating multiple functions such as oxide film detection, rod diameter measurement detection, damage detection, and video detection, this full-scale fuel assembly simulation body multi-functional test and verification device can provide comprehensive and effective detection functions for the fuel assembly inspection system, ensure the consistency between the detection environment and the actual use environment, thereby improving the reliability of the detection results, and being more accurate and efficient for verifying the usability of the fuel assembly inspection system.

[0054] Such as Figure 2As shown, the outer oxide film simulation tube assembly 22 is installed on the outermost side of the grid simulator 1. The outer oxide film simulation tube assembly 22 includes an outer simulation upper base 221, an outer simulation upper fixing part 222, an outer oxide film calibration part 223, an outer simulation lower fixing part 224, and an outer simulation lower base 225 that are sequentially connected in the axial direction. It can be understood that the outer oxide film simulation tube assembly 22 is used to meet the single-rod detection requirements of the outer fuel rod and the test requirements of the blade-type probe. Different thickness outer oxide film calibration parts 223 can be installed to ensure that the electromagnetic characteristics of the outer oxide film simulation tube assembly 22 are consistent with the on-site situation. The outer oxide film calibration part 223 straddles one of the grid simulators 1, and can simulate the measurement of the oxide film thickness of the outer fuel rod at the position across the grid by the on-site outer oxide film measuring device. In addition, the outer simulation upper base 221 can be threadedly connected to the outer simulation upper fixing part 222, and the outer simulation lower base 225 can be threadedly connected to the outer simulation lower fixing part 224. Both the outer simulation upper fixing part 222 and the outer simulation lower fixing part 224 are provided with connection grooves for connecting with the outer oxide film calibration part 223. The inner parts of the outer simulation upper fixing part 222 and the outer simulation lower fixing part 224 are provided with pins and threads. Both the outer simulation upper fixing part 222 and the outer simulation lower fixing part 224 can be detachably connected to the outer oxide film calibration part 223, and the outer simulation upper fixing part 222 and the outer simulation lower fixing part 224 form a quick-release structure. There are two reasons for setting this quick-release structure: 1. Protect the outer oxide film calibration part 223: The positions inside the grid simulator 1 that contact the outer simulation upper base 221 or the outer simulation lower base 225 are equipped with tight spring pieces. The outer simulation upper base 221 or the outer simulation lower base 225 may be slightly scratched during the process of passing through multiple grid simulators 1. If the outer oxide film calibration part 223 is installed before being inserted into the grid simulator 1, the surface may be scratched, thus affecting subsequent test verification. 2. Material compatibility: For fuel rods of different materials, the corresponding material outer oxide film calibration part 223 can be replaced through the quick-release structure to meet the test requirements of the outer oxide film calibration parts 223 of various materials subsequently.

[0055] In addition, as Figure 4As shown, the inner oxide film simulation tube assembly 23 is installed inside the grid simulator 1. The inner oxide film simulation tube assembly 23 includes an inner simulation upper base 231, an inner simulation upper fixing part 232, an inner oxide film calibration part 233, an inner simulation lower fixing part 234, and an inner simulation lower base 235 that are sequentially connected in the axial direction. The inner oxide film calibration part 233 is arranged between adjacent grid simulators 1. It can be understood that the inner oxide film simulation tube assembly 23 is used to meet the single-rod detection requirements of the inner fuel rod and the test requirements of the blade-type probe. Different thickness inner oxide film calibration parts 233 can be installed to ensure that the electromagnetic characteristics of the inner oxide film simulation tube assembly 23 are consistent with the field. By being arranged between adjacent grid simulators 1, it can simulate the measurement of the oxide film thickness of the fuel rod arranged between adjacent grid simulators 1 by the on-site inner oxide film measuring device. The overall connection structure of the inner oxide film simulation tube assembly 23 is the same as that of the outer oxide film simulation tube assembly 22, and its principle will not be elaborated here.

[0056] As Figure 2 shown, the rod diameter test simulation tube assembly 24 includes a plurality of rod diameter measurement quick-release parts 241, a plurality of rod diameter measurement calibration blocks 242, and a plurality of rod diameter measurement bases 243. Each rod diameter measurement base 243 and each rod diameter measurement calibration block 242 are connected through the rod diameter measurement quick-release part 241. The plurality of rod diameter measurement calibration blocks 242 are solid rods with different diameters. It can be understood that the rod diameter test simulation tube assembly 24 is used to provide a test function for the rod diameter measuring device. The rod diameter measuring device can measure the rod diameter of the rod diameter measurement calibration block 242 through a high-precision sensor. The plurality of rod diameter measurement calibration blocks 242 are solid rods with different diameters and are connected through the rod diameter measurement quick-release part 241 to avoid scratches on the rod diameter measurement calibration block 242 affecting the accuracy of rod diameter measurement. In this embodiment, the number of the rod diameter measurement calibration blocks 242 is 5, and 5 rod diameter measurement calibration blocks 242 with different diameters are installed on the rod diameter measurement base 243 at the same time, and the diameter range covers the diameter change range of the fuel rod during its entire service life.

[0057] As Figure 3As shown in the figure, water seepage holes 251 are provided on the damaged test simulation tube base body 25. It can be understood that the damaged test simulation tube base body 25 is used to simulate the situation of fuel rod damage. By providing water seepage holes 251 on the damaged test simulation tube base body 25, water is infiltrated through the water seepage holes 251 to ensure that the detection simulation of fuel rod damage is closer to the actual environment. The detection principle of the damaged test simulation tube base body 25 is as follows: Ultrasonic wave propagation and reflection. Under normal circumstances, there is a gap filled with helium and fission gas between the cladding of the fuel rod and the fuel particles. When the fuel rod fails, water will infiltrate into this gap. Due to the different propagation characteristics of ultrasonic waves in different media, when ultrasonic waves propagate from the zirconium alloy tube wall (the cladding material of the fuel rod) to the gas or water in the gap, due to the difference in acoustic impedance, reflection will occur. The acoustic impedance of gas is much lower than that of water. Therefore, when the gap is filled with gas, the energy of the reflected ultrasonic wave is less; while when the gap is filled with water, the energy of the reflected ultrasonic wave will increase significantly. The pulse emitted by the ultrasonic probe in the echo signal analysis is reflected multiple times within the fuel rod wall, forming a series of echoes. The amplitude of these echoes will decay as the number of reflections increases. For an undamaged fuel rod, the decay of the echo amplitude is slower; while for a damaged fuel rod, due to the presence of water, the decay of the echo amplitude will be faster. This decay difference is the key to detecting whether the fuel rod is damaged.

[0058] As Figure 3 shown, at least one grid simulation member 1 is provided with a first groove 11, and the video test simulation tube base body 26 is provided with a second groove 261. It can be understood that the setting of the first groove 11 and the second groove 261 is aimed at detecting the wear, fracture and foreign object mixing of the fuel assembly, and can effectively identify the damage of the assembly structure and the influence of external foreign objects. By providing the first groove 11 on the grid simulation member 1 and the second groove 261 on the video test simulation tube base body 26, the first groove 11 and the second groove 261 are video-detected by a video detection device to verify the sensitivity of the video detection device for detecting the fuel assembly in an underwater environment.

[0059] In this embodiment, a verification method for a full-size fuel assembly simulation body multi-functional test verification device is also constructed. Based on the above-mentioned full-size fuel assembly simulation body multi-functional test verification device, it includes the following steps:

[0060] S1. Install the basic simulation tube base body 21, the outer oxide film simulation tube assembly 22, the inner oxide film simulation tube assembly 23, the rod diameter test simulation tube assembly 24 and the damaged test simulation tube base body 25 on multiple grid simulation members 1;

[0061] S2. Use the outer oxide film measuring device to measure the thickness of the outer oxide film calibration piece 223 of the outer oxide film simulation tube assembly 22;

[0062] S3. Use the inner oxide film measuring device to measure the thickness of the inner oxide film calibration piece 233 of the inner oxide film simulation tube assembly 23;

[0063] S4. Use the rod diameter measuring device to measure the rod diameters of the multiple rod diameter measuring calibration blocks 242 of the rod diameter test simulation tube assembly 24;

[0064] S5. Process a first groove 11 on one of the grid simulation pieces 1, process a second groove 261 on the video test simulation tube matrix 26, and use the video detection device to perform video detection on the first groove 11 and the second groove 261;

[0065] S6. Make water seep in through the water seepage holes 251 on the damaged test simulation tube matrix 25 to simulate the situation of fuel rod damage.

[0066] In addition, during the process of installing the outer oxide film simulation tube assembly 22 on the grid simulation piece 1, first install it using an outer oxide film sacrificial piece with the same shape as the outer oxide film calibration piece 223, and replace the outer oxide film sacrificial piece with the outer oxide film calibration piece 223 after the rod pulling process of the outer oxide film simulation tube assembly 22;

[0067] During the process of installing the inner oxide film simulation tube assembly 23 on the grid simulation piece 1, first install it using an inner oxide film sacrificial piece with the same shape as the inner oxide film calibration piece 233, and replace the inner oxide film sacrificial piece with the inner oxide film calibration piece 233 after the rod pulling process of the inner oxide film simulation tube assembly 23;

[0068] During the process of installing the rod diameter test simulation tube assembly 24 on the grid simulation piece 1, first install it using a rod diameter measuring sacrificial piece with the same shape as the rod diameter measuring calibration block 242, and replace the rod diameter measuring sacrificial piece with the rod diameter measuring calibration block 242 after the rod pulling process of the rod diameter test simulation tube assembly 24.

[0069] The above installation process can prevent the spring pieces of the grid strips from scratching the outer oxide film calibration piece 223, the inner oxide film calibration piece 233, and the rod diameter measuring calibration block 242 during the rod pulling process.

[0070] In step S5, by using the artificial electric spark or laser grooving method on one of the grid simulation pieces 1, the first groove 11 is processed on the grid simulation piece 1; by using the artificial electric spark or laser grooving method on the video test simulation tube matrix 26, the second groove 261 is processed on the video test simulation tube matrix 26. Use the video detection device to perform video detection on the first groove 11 and the second groove 261 to verify the sensitivity of the video detection device for detecting the fuel assembly in the underwater environment.

[0071] Understandably, the above embodiments only represent the preferred embodiments of the present invention, and their descriptions are relatively specific and detailed. However, it should not be construed as a limitation to the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, the above technical features can be freely combined, and several deformations and improvements can also be made, which all fall within the protection scope of the present invention. Therefore, all equivalent transformations and modifications made to the scope of the claims of the present invention shall fall within the scope covered by the claims of the present invention.

Claims

1. A full-size fuel assembly simulation multifunctional test verification device, used to provide test functions for a fuel assembly inspection system, the fuel assembly inspection system includes an outer oxide film measuring device, an inner oxide film measuring device, a rod diameter measuring device and a video detection device, characterized in that: The full-size fuel assembly simulation body multifunctional testing and verification device comprises a plurality of grid simulation parts (1) and a tube simulation mechanism (2); The plurality of grid simulation members (1) are arranged in a spaced-apart manner along a height direction, and the tube simulation mechanism (2) is mounted on the plurality of grid simulation members (1); The pipe body simulation mechanism (2) comprises a plurality of basic simulation pipe substrates (21), at least one outer oxide film simulation pipe assembly (22), at least one inner oxide film simulation pipe assembly (23), at least one rod diameter test simulation pipe assembly (24), at least one damage test simulation pipe substrate (25) and at least one video test simulation pipe substrate (26); The basic simulation tube matrix (21) is used to simulate the on-site basic fuel rod; The outer oxide film simulation tube assembly (22) is used to provide a test function for the outer oxide film measuring device; The inner oxide film simulation tube assembly (23) is used to provide a test function for the inner oxide film measuring device; The rod diameter test simulation tube assembly (24) is used to provide a test function for the rod diameter measuring device; The damage test simulation tube matrix (25) is used to simulate the damage of the fuel rod; The video test simulation tube substrate (26) is used to provide a test function for the video detection device.

2. The full-size fuel assembly simulation multifunctional test verification device according to claim 1 is characterized in that: The outer oxide film simulation tube assembly (22) is installed on the outermost side of the grid simulation component (1); The outer layer oxide film simulation tube assembly (22) comprises an outer layer simulation upper substrate (221), an outer layer simulation upper fixing piece (222), an outer layer oxide film calibration piece (223), an outer layer simulation lower fixing piece (224), and an outer layer simulation lower substrate (225) which are sequentially connected in the axial direction; The outer oxide film calibration piece (223) spans across one of the grid simulation pieces (1).

3. The full-size fuel assembly simulation multifunctional test verification device according to claim 1, characterized in that: The inner oxide film simulation tube assembly (23) is installed on the inner side of the grid simulation component (1); The inner layer oxide film simulation tube assembly (23) comprises an inner layer simulation upper substrate (231), an inner layer simulation upper fixing piece (232), an inner layer oxide film calibration piece (233), an inner layer simulation lower fixing piece (234), and an inner layer simulation lower substrate (235) which are sequentially connected in the axial direction; The inner oxide film calibration piece (233) is arranged between adjacent grid simulation pieces (1).

4. The full-scale fuel assembly simulation multifunctional test verification device according to claim 1, characterized in that: The rod diameter test simulation tube assembly (24) comprises a plurality of rod diameter measurement quick-release parts (241), a plurality of rod diameter measurement calibration blocks (242) and a plurality of rod diameter measurement substrates (243); Each of the rod diameter measurement base bodies (243) and each of the rod diameter measurement calibration blocks (242) are connected via the rod diameter measurement quick-release component (241); The plurality of rod diameter measurement calibration blocks (242) are solid rods with different diameters.

5. The full-scale fuel assembly simulation multifunctional test verification device according to claim 1, characterized in that: The damage test simulation pipe base (25) is provided with a water seepage hole (251).

6. The full-scale fuel assembly simulation multifunctional test verification device according to claim 1, characterized in that: At least one of the grid simulation parts (1) is provided with a first groove (11), and the video test simulation tube substrate (26) is provided with a second groove (261).

7. The full-scale fuel assembly simulation multifunctional test verification device according to claim 1, characterized in that: The full-size fuel assembly simulation body multifunctional test verification device also includes an upper tube seat simulation body (3) and a lower tube seat simulation body (4), and a plurality of grid simulation parts (1) and a tube body simulation mechanism (2) are installed between the upper tube seat simulation body (3) and the lower tube seat simulation body (4).

8. A verification method for a full-size fuel assembly simulation multifunctional test verification device, which is based on the full-size fuel assembly simulation multifunctional test verification device according to any one of claims 1 to 7, characterized in that: Includes steps: S1, installing a basic simulated pipe matrix (21), an outer oxide film simulated pipe assembly (22), an inner oxide film simulated pipe assembly (23), a rod diameter test simulated pipe assembly (24), and a damage test simulated pipe matrix (25) on a plurality of grid simulation parts (1); S2, using an outer oxide film measuring device to measure the outer oxide film thickness of the outer oxide film calibration piece (223) of the outer oxide film simulation pipe assembly (22); S3, using an inner oxide film measuring device to measure the inner oxide film thickness of the inner oxide film calibration piece (233) of the inner oxide film simulation pipe assembly (23); S4, using a rod diameter measuring device to measure the rod diameters of a plurality of rod diameter measurement calibration blocks (242) of the rod diameter test simulation tube assembly (24); S5, processing a first groove (11) on one of the grid simulation parts (1), processing a second groove (261) on the video test simulation tube substrate (26), and performing video detection on the first groove (11) and the second groove (261) using a video detection device; S6. Water is allowed to penetrate through the water seepage holes (251) on the damage test simulation tube base (25) to simulate the damage of the fuel rod.

9. The verification method of the full-scale fuel assembly simulation multifunctional test verification device according to claim 8, characterized in that: During the process of installing the outer oxide film simulation tube assembly (22) on the grid simulation component (1), an outer oxide film sacrificial component having the same shape as the outer oxide film calibration component (223) is first used for installation, and after the rod drawing process of the outer oxide film simulation tube assembly (22), the outer oxide film calibration component (223) is used to replace the outer oxide film sacrificial component; During the process of installing the inner oxide film simulation tube assembly (23) on the grid simulation component (1), an inner oxide film sacrificial component having the same shape as the inner oxide film calibration component (233) is first used for installation, and after the rod drawing process of the inner oxide film simulation tube assembly (23), the inner oxide film calibration component (233) is used to replace the inner oxide film sacrificial component; During the process of installing the rod diameter test simulation tube assembly (24) on the grid simulation component (1), a rod diameter measurement sacrificial component having the same shape as the rod diameter measurement calibration block (242) is first used for installation, and after the rod pulling process of the rod diameter test simulation tube assembly (24), the rod diameter measurement calibration block (242) is used to replace the rod diameter measurement sacrificial component.

10. The verification method of the full-scale fuel assembly simulation multifunctional test verification device according to claim 8, characterized in that: In step S5, a first groove (11) is machined on one of the grid simulation parts (1) by performing an artificial electric spark or laser groove engraving method on the grid simulation part (1); The video test simulation tube substrate (26) is subjected to an artificial electric spark or laser grooving method to form a second groove (261) on the video test simulation tube substrate (26).

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