Crack damage characterization method, equipment and medium for key part of nuclear-grade structural member

Abstract

The invention relates to a nuclear-grade structural member key part crack damage characterization method, equipment and a medium, a key concern area is monitored through a monitor with a fixed position, a monitoring image is intercepted, the intercepted image is subjected to image processing through Matlab, an original image, a grayscale image and a binary image are respectively obtained, and the original image, the grayscale image and the binary image are subjected to image processing; the method comprises the following steps of: checking the size of a matrix corresponding to a binary image, properly adjusting the binary image, calculating a fractal dimension corresponding to the binary image, and converting the fractal dimension into a damage index to obtain a corresponding damage degree value, so that the damage characterization and monitoring of the nuclear-grade structural member are realized. Compared with the prior art, the calculation and characterization method of the damage index avoids manual judgment, and the result accuracy is higher. Meanwhile, according to the method, the situation that manual detection cannot be carried out in an extreme environment is avoided through real-time monitoring of pictures of a monitor.

Description

Technical Field

[0001] The invention relates to the technical field of material surface properties, and in particular to a method, equipment and medium for characterizing crack damage at key parts of a nuclear-grade structural component. Background Art

[0002] With the continuous development of science and technology, more and more high-performance materials are widely used in aerospace, microelectronics, nuclear industry and other fields. However, the characterization and monitoring of material properties in these fields are also crucial and difficult. For example, cracks in nuclear-grade special equipment can easily cause equipment damage and stop running, which will cause huge economic losses. Moreover, once the special equipment is installed, it is relatively complicated to disassemble. Therefore, damage characterization and health monitoring of nuclear-grade special equipment are particularly important.

[0003] At present, the damage factor of materials is often defined by the fractal dimension of cracks. For example: CN113222992B discloses a crack feature characterization method and system based on multiple fractal spectra, which visualizes the crack image by combining the singularity index of the multiple fractal spectrum, the multiple fractal singular spectrum and the preset weight factor, thereby characterizing the geometric distribution of the crack in combination with the fractal dimension; CN113836776B discloses a method for constructing a blasting damage prediction model, which obtains the fractal dimension by writing a fractal dimension calculation program through MATLAB software, and obtains the corresponding damage variable by combining ANSYS software simulation, thereby establishing the relationship between the fractal dimension and the degree of damage. CN105893716B discloses a non-probabilistic reliability analysis method for structural cracks based on fractal theory, which establishes an interference model of non-probabilistic stress intensity factor by considering the geometric uncertainty of finite samples and the uncertainty of crack toughness, and obtains the reliability of the cracked structure. These studies mainly focus on characterizing structures that have already been damaged or are known to be damaged. However, in the fields of nuclear industry, aerospace, etc., real-time monitoring and characterization of structural parts are often required to avoid major accidents.

[0004] Therefore, there is an urgent need to develop a method that can monitor and characterize the damage degree of cracks on nuclear-grade structural components in real time. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a method, device and medium for characterizing crack damage in key parts of nuclear-grade structural parts. By adopting fractal theory and MATLAB image processing technology, the crack damage degree of key parts of nuclear-grade structural parts is obtained, thereby achieving the purpose of health monitoring of nuclear-grade structural parts.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] The present invention provides a method for characterizing crack damage in key parts of nuclear-grade structural parts. The method comprises: acquiring images of key focus areas in key parts of nuclear-grade structural parts, intercepting the acquired images at fixed intervals, converting the intercepted images into grayscale images, then converting the grayscale images into binary images, calculating the fractal dimension corresponding to the binary images, converting the fractal dimension into a damage index, and obtaining the crack damage degree of the key parts of the nuclear-grade structural parts.

[0008] Furthermore, the key focus areas are areas or connection areas in the radiation-resistant structure inside the nuclear island where cracks are prone to occur.

[0009] Furthermore, the fixed interval is specifically intercepted every 1 hour.

[0010] Furthermore, the image of the key focus area is specifically a monitoring image obtained in a monitoring instrument, and the position of the monitoring instrument and the key part of the nuclear-grade structural component is relatively fixed.

[0011] Furthermore, the binary image is 2 n ×2 n phalanx;

[0012] The size of n is obtained by taking the logarithm of the minimum value of the binary image matrix and rounding it down to the integer with base 2.

[0013] Furthermore, after being converted into a binary image, the binary image is traversed and the number of boxes is counted. Meanwhile, the binary image is normalized and the corresponding fractal dimension is calculated.

[0014] Furthermore, the calculation formula of the fractal dimension is:

[0015]

[0016] Where N(r) represents the number of boxes. r represents the grid side length, and D represents the fractal dimension.

[0017] Furthermore, the corresponding relationship between fractal dimension and damage index is:

[0018]

[0019] Where S represents the damage index and D0 represents the box dimension when there is no crack.

[0020] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, a method for characterizing crack damage in a key part of a nuclear-grade structural component is implemented.

[0021] The present invention also provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, a method for characterizing crack damage in a key part of a nuclear-grade structural component is implemented.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0023] The present invention adopts a monitoring instrument to monitor the key parts of nuclear-grade structural parts in real time and obtain images, intercepts the acquired images and imports them into Matlab, processes the intercepted images and calculates the corresponding fractal dimensions and damage indicators, avoiding human subjective judgment throughout the process, and the credibility of the results is high, which is conducive to real-time health monitoring and operation and maintenance management of nuclear-grade structural parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic flow chart of a method for characterizing crack damage in a key part of a nuclear-grade structural component in Example 1;

[0025] Figure 2 This is the original image of the nuclear-grade structural component with crack structure in Example 2;

[0026] Figure 3 is a grayscale image of a nuclear-grade structural component with a crack structure in Example 2;

[0027] Figure 4 This is a binary image of the nuclear-grade structural component containing a crack structure in Example 2. DETAILED DESCRIPTION

[0028] The specific implementation methods of the present invention are described in detail below through examples. These examples are implemented on the premise of the scheme described in the present invention, and provide detailed implementation methods and specific operating processes, but the protection scope of the present invention is not limited to the following examples.

[0029] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. Any features such as component models, material names, connection structures, preparation methods, materials, structures or composition ratios not clearly described in this technical solution are deemed to be common technical features disclosed in the prior art.

[0030] Example 1

[0031] This embodiment provides a method for characterizing crack damage in key parts of nuclear-grade structural parts. Figure 1 As shown, the following steps are included:

[0032] S1: Obtain images of key focus areas from the monitor, and the positions of the monitor and the key parts of the nuclear-grade structural parts are relatively fixed. The key focus areas are areas or connection areas that are prone to cracks in the radiation-resistant structures inside the nuclear island.

[0033] S2: Import the image acquired in S1 into Matlab software;

[0034] S3: The images obtained in S1 were intercepted every 1 hour using Matlab;

[0035] S4: Convert the image captured in S3 into a grayscale image using Matlab;

[0036] S5: Use Matlab to convert the grayscale image in S4 into a binary image. The binary image is 2 n ×2 n The size of n is obtained by taking the logarithm of the minimum value of the binary image matrix and rounding it down to the integer with the base 2. Processing the acquired image into a square matrix facilitates the complete coverage and traversal of the subsequent box dimension calculation and statistics, and also facilitates the selection of the box dimension size.

[0037] S6: Use Matlab to traverse the binary image in S5, count the number of boxes, normalize the binary image, and calculate the corresponding fractal dimension. The calculation formula of the fractal dimension is:

[0038]

[0039] Where N(r) represents the number of boxes. r represents the grid side length, and D represents the fractal dimension.

[0040] The corresponding relationship between fractal dimension and damage index is:

[0041]

[0042] Where S represents the damage index and D0 represents the box dimension when there is no crack.

[0043] The damage index is automatically identified and calculated by the computer, avoiding interference from human factors, and the results are more accurate, providing certain technical support for the reliability evaluation of actual production. Through monitoring and shooting by the monitor, the problem of being unable to be manually detected under actual complex working conditions is solved, which is helpful for real-time monitoring of nuclear-grade structural parts.

[0044] Example 2

[0045] This embodiment demonstrates the method in embodiment 1, and obtains an image of a cracked structural part as shown in FIG. Figure 2 As shown in the figure, the processed grayscale image and the binary image when n is 8 are respectively Figure 3 and Figure 4 shown.

[0046] Example 3

[0047] This embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements a method for characterizing crack damage in a key part of a nuclear-grade structural component as described in Embodiment 1 when executing the program. The processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components; the memory may include a random access memory (RAM), and may also include a non-volatile memory, such as at least one disk storage. The memory may be an internal memory of a random access memory (RAM), and the processor and memory may be integrated into one or more independent circuits or hardware, such as an application-specific integrated circuit (ASIC). It should be noted that the computer program in the above-mentioned memory can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, an electronic device, or a network device, etc.) to perform all or part of the steps of the methods of various embodiments of the present invention.

[0048] Example 4

[0049] The present embodiment provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements a method for characterizing crack damage in a key part of a nuclear-grade structural component as described in Embodiment 1. The storage medium may be an electronic medium, a magnetic medium, an optical medium, an electromagnetic medium, an infrared medium, or a semiconductor system or a propagation medium. The storage medium may also include a semiconductor or solid-state memory, a magnetic tape, a removable computer disk, a random access memory (RAM), a read-only memory (ROM), a hard disk, and an optical disk. The optical disk may include a compact disk-read-only memory (CD-ROM), a compact disk-read / write (CD-RW), and a DVD.

[0050] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A method for characterizing crack damage in key parts of nuclear-grade structural parts, characterized in that: The method comprises: acquiring an image of a key focus area in a key part of a nuclear-grade structural component, intercepting the acquired image at a fixed interval, converting the intercepted image into a grayscale image, then converting the grayscale image into a binary image, calculating a fractal dimension corresponding to the binary image, and converting the fractal dimension into a damage index, thereby obtaining the crack damage degree of the key part of the nuclear-grade structural component.

2. The method for characterizing crack damage in key parts of a nuclear-grade structural component according to claim 1, characterized in that: The key areas of concern are areas or connection areas that are prone to cracks in the radiation-resistant structure inside the nuclear island.

3. The method for characterizing crack damage in key parts of a nuclear-grade structural component according to claim 1, characterized in that: The fixed interval is specifically every 1 hour.

4. The method for characterizing crack damage in key parts of a nuclear-grade structural component according to claim 1, characterized in that: The image of the key focus area is specifically a monitoring image obtained in a monitoring instrument, and the position of the monitoring instrument and the key part of the nuclear-grade structural component is relatively fixed.

5. The method for characterizing crack damage in key parts of a nuclear-grade structural component according to claim 1, characterized in that: The binary image is 2 n ×2 n phalanx; The size of n is obtained by taking the logarithm of the minimum value of the binary image matrix and rounding it down to the integer with base 2.

6. The method for characterizing crack damage in key parts of a nuclear-grade structural component according to claim 1, characterized in that: After conversion into a binary image, the binary image is traversed and the number of boxes is counted. At the same time, the binary image is normalized and the corresponding fractal dimension is calculated.

7. The method for characterizing crack damage in key parts of a nuclear-grade structural component according to claim 6, characterized in that: The calculation formula of the fractal dimension is: Where N(r) represents the number of boxes. r represents the grid side length, and D represents the fractal dimension.

8. The method for characterizing crack damage in key parts of a nuclear-grade structural component according to claim 1, characterized in that: The corresponding relationship between fractal dimension and damage index is: Where S represents the damage index and D0 represents the box dimension when there is no crack.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, a method for characterizing crack damage in a key part of a nuclear-grade structural component as described in any one of claims 1-8 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, a method for characterizing crack damage in a key part of a nuclear-grade structural component as described in any one of claims 1 to 8 is implemented.

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