Method for detecting radioactive contamination of irregular materials

Abstract

The invention discloses a method for detecting radioactive contamination of an irregular material, and the method comprises the following steps: randomly selecting a point from the point cloud data of the irregular material according to the contamination type of the irregular material, and taking the point as a ray emission point; randomly selecting a point in the detector end face of the detector as a detection point; taking a point where a connecting line of the emission point and the detection point intersects with the surface of the irregular material as a penetration point; repeatedly extracting the emission points and the detection points for a preset number of times; and calculating the radioactive contamination of the irregular material according to the distance between the emission point and the penetration point extracted by the preset number of times and the distance between the detection point and the penetration point extracted by the preset number of times. The method solves the problems that radioactive contamination of large-size irregular materials cannot be calculated, and a scale source needs to be formulated according to material media, or the technical requirements for implementation personnel are high, simulation calculation time is long, and the method is not easy to transplant in an existing method.

Description

Technical Field

[0001] The invention relates to the technical field of radioactive detection, and in particular to a method for detecting radioactive contamination of irregular materials. Background Art

[0002] In nuclear power plants, nuclear reprocessing plants, radiopharmaceutical production, accelerator therapy and other fields involving radioactivity, a certain amount of solid radioactive waste is usually generated. Usually, solid radioactive waste is stored in radioactive waste barrels ranging from 50L to 400L. According to relevant national requirements, before solid radioactive waste is sent out, it is necessary to measure the radioactive waste to obtain characteristics such as the type of radioactive waste nuclides, activity concentration and surface radiation dose rate level.

[0003] At present, radioactive solid waste of specific geometric shapes is mainly measured by SGS, TGS and other technologies. SGS technology is a non-destructive detection technology used to detect the type and activity of radionuclides in radioactive solid waste. TGS technology is also a non-destructive detection technology, which is mainly used to characterize low- and medium-level radioactive wastes generated during the operation of nuclear power plants and other nuclear facilities. However, there is no feasible measurement method for irregular materials. Usually, they need to be prepared, classified and stored in specific containers or cabinets, and then the cabinet materials are measured. A major problem in the measurement of radioactive waste is that the volume of the material is large (50L~400L). It is difficult to prepare a radioactive calibration source of the same size and medium for large-volume materials, and the surface contamination detection efficiency of thick objects cannot be calculated by using the calibration source method.

[0004] There are two main methods at present, one is the Monte Carlo simulation calibration method, and the other is to use line sources (or point sources) to distribute in a certain pattern in the matrix to simulate uniform body sources. The Monte Carlo simulation calibration method has problems such as high technical requirements for implementation personnel, long simulation calculation time, and difficulty in transplantation. The method of using line sources (or point sources) to distribute in a certain pattern in the matrix to simulate uniform body sources has large errors, and for different matrices, the number and distribution of line sources are quite different. In order to realize the calibration of materials of different media, a large number of calibration sources need to be prepared. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for detecting radioactive contamination of irregular materials in view of at least one defect of the related technology mentioned in the above background technology: it is impossible to calculate the radioactive contamination of large-volume irregular materials, and the current method has the problems of needing to formulate a calibration source according to the material medium, or having high technical requirements for the implementers, long simulation calculation time, and difficulty in transplantation.

[0006] The technical solution adopted by the present invention to solve the technical problem is: construct a method for detecting radioactive contamination of irregular materials, the method comprising the following steps:

[0007] According to the pollution type of the irregular material, a point is randomly selected from the point cloud data of the irregular material as the emission point of the ray;

[0008] A point is randomly selected within the detector end face of the detector as a detection point;

[0009] The point where the line connecting the emission point and the detection point intersects with the irregular material surface is taken as the penetration point;

[0010] Repeat the extraction of emission points and detection points for a preset number of times;

[0011] The radioactive contamination of irregular materials is calculated based on the distance between the emission point and the penetration point drawn at a preset number of times and the distance between the detection point and the penetration point drawn at a preset number of times.

[0012] In some embodiments, a point is randomly selected from the point cloud data of the irregular material according to the pollution type of the irregular material as the emission point of the ray, and the method also includes:

[0013] Determine the contamination type of irregular materials.

[0014] In some embodiments, determining the contamination type of the irregular material includes:

[0015] Determine the irregular material pollution type based on the irregular material pollution source items and irregular material materials.

[0016] In some embodiments, determining the type of irregular material pollution further includes:

[0017] By performing 3D scanning on irregular materials, point cloud data of irregular materials can be obtained.

[0018] In some embodiments, irregular material contamination types include: body contamination and surface contamination;

[0019] The point cloud data of irregular materials include: irregular material voxel point cloud data and irregular material surface point cloud data.

[0020] In some embodiments, randomly selecting a point in the point cloud data of the irregular material according to the pollution type of the irregular material as the emission point of the ray includes:

[0021] If the irregular material pollution type is volume pollution, a point is randomly selected from the irregular material voxel point cloud data as the voxel emission point of the ray, recorded as s1(x, y, z);

[0022] If the irregular material contamination type is surface contamination, a point is randomly selected from the irregular material surface point cloud data as the surface emission point of the ray, recorded as s(x, y, z);

[0023] And, the detection point is recorded as d(x,y,z).

[0024] In some embodiments, the point where the line connecting the emission point and the detection point intersects with the irregular material surface is used as the penetration point, including:

[0025] If the irregular material contamination type is volume contamination, the point where the line connecting the voxel emission point s1(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface is taken as the voxel penetration point t1(x, y, z);

[0026] If the irregular material contamination type is surface contamination, the point where the line connecting the surface emission point s(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface is taken as the surface penetration point t(x, y, z).

[0027] In some embodiments, if the irregular material contamination type is surface contamination, the point where the line connecting the surface emission point s(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface is taken as the surface penetration point t(x, y, z), including:

[0028] If the irregular material pollution type is surface pollution, determine whether the line connecting the surface emission point s(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface;

[0029] If so, the surface emission point s(x,y,z) is a surface emission point that is not within the detection range of the detector, recorded as s2(x,y,z), and the point where the line connecting the surface emission point s2(x,y,z) that is not within the detection range of the detector and the detection point d(x,y,z) intersects with the irregular material surface is taken as the surface penetration point t2(x,y,z);

[0030] If not, the surface emission point s(x, y, z) is the surface emission point within the detection range of the detector, recorded as s3(x, y, z), and there is no surface penetration point.

[0031] In some embodiments, repeatedly extracting emission points and detection points a preset number of times includes: if the irregular material contamination type is volume contamination, repeatedly extracting voxel emission points s1(x, y, z) and detection points d(x, y, z) p times;

[0032] The radioactive contamination of the irregular material is calculated according to the distance between the emission point and the penetration point extracted for a preset number of times and the distance between the detection point and the penetration point extracted for a preset number of times, including: if the irregular material contamination type is volume contamination, the radioactive contamination ε of the irregular material volume is calculated according to the distance l1 between the voxel emission point s1(x, y, z) extracted for p times and the voxel penetration point t1(x, y, z) and the distance l1' between the detection point d(x, y, z) extracted for p times and the voxel penetration point t1(x, y, z) V ;

[0033] Radioactive contamination of irregular materialsε V The calculation formula is:

[0034] Among them, μ is the linear attenuation coefficient of the material, l1 is the distance from the k-th sampling voxel emission point s1(x,y,z) to the detection point d(x,y,z), and l1' is the distance from the k-th sampling voxel emission point s1(x,y,z) to the voxel penetration point t1(x,y,z).

[0035] In some embodiments, repeatedly extracting emission points and detection points a preset number of times includes: if the irregular material contamination type is surface contamination, determining whether the surface emission point is within the detection range of the detector;

[0036] If the surface emission point is a surface emission point s2(x,y,z) that is not within the detection range of the detector, then the surface emission point s2(x,y,z) that is not within the detection range of the detector and the detection point d(x,y,z) are repeatedly sampled n times;

[0037] If the surface emission point is the surface emission point s3(x,y,z) within the detection range of the detector, then the surface emission point s3(x,y,z) and the detection point d(x,y,z) within the detection range of the detector are repeatedly sampled m times;

[0038] The radioactive contamination of irregular materials is calculated based on the distance between the emission point and the penetration point drawn at a preset number of times and the distance between the detection point and the penetration point drawn at a preset number of times, including: if the irregular material contamination type is surface contamination, determining whether the surface emission point is within the detection range of the detector;

[0039] If the surface emission point is a surface emission point s2(x,y,z) that is not within the detection range of the detector, then according to the distance l2 between the surface emission point s2(x,y,z) that is not within the detection range of the detector and the surface penetration point t2(x,y,z) extracted n times and the distance l2' between the detection point d(x,y,z) extracted n times and the surface penetration point t2(x,y,z); and,

[0040] If the surface emission point is a surface emission point s3(x,y,z) within the detection range of the detector, then the radioactive contamination ε of the irregular material surface is calculated based on the distance l3 between the surface emission point s3(x,y,z) within the detection range of the detector extracted m times and the detection point d(x,y,z). S ;

[0041] Radioactive contamination on irregular material surfacesε S The calculation formula is:

[0042] Wherein, μ is the linear attenuation coefficient of the material, l2 is the distance from the surface emission point s2(x,y,z) that is not within the detection range of the detector to the detection point d(x,y,z) of the i-th sampling, and l2' is the distance from the surface emission point s2(x,y,z) that is not within the detection range of the detector to the surface penetration point t2(x,y,z) of the i-th sampling;

[0043] l3 is the distance from the surface emission point s3(x,y,z) to the detection point d(x,y,z) within the detection range of the detector for the jth sampling.

[0044] By implementing the present invention, the following beneficial effects are achieved:

[0045] The present invention randomly extracts a point in the point cloud data of the irregular material according to the pollution type of the irregular material as the emission point of the ray; randomly extracts a point in the detector end face of the detector as the detection point; uses the point where the line connecting the emission point and the detection point intersects with the surface of the irregular material as the penetration point; repeatedly extracts the emission point and the detection point for a preset number of times; calculates the radioactive contamination of the irregular material according to the distance between the emission point and the penetration point extracted for the preset number of times and the distance between the detection point and the penetration point extracted for the preset number of times, thereby realizing the calculation of the radioactive contamination of large-volume irregular materials and eliminating the problems of the current method that a calibration source needs to be formulated according to the material medium or the technical requirements for the implementers are high, the simulation calculation time is long, and the method is not easy to transplant. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0047] Figure 1 A flow chart of an embodiment of a method for detecting radioactive contamination of irregular materials according to the present invention is shown;

[0048] Figure 2 A schematic diagram showing a method for detecting radioactive contamination of irregular materials according to an embodiment of the present invention for performing 3D scanning on irregular materials is shown;

[0049] Figure 3A schematic diagram showing voxel point cloud data and surface point cloud data of point cloud data of irregular materials obtained in one embodiment of the method for detecting radioactive contamination of irregular materials of the present invention;

[0050] Figure 4 A schematic diagram of surface point cloud data of an irregular material is shown in one embodiment of the method for detecting radioactive contamination of an irregular material according to the present invention;

[0051] Figure 5 A schematic diagram showing a sampling when calculating the radioactive contamination of an irregular material body in one embodiment of the method for detecting radioactive contamination of an irregular material according to the present invention;

[0052] Figure 6 A schematic diagram showing a sampling when calculating the radioactive contamination on the surface of an irregular material in one embodiment of the method for detecting radioactive contamination of an irregular material according to the present invention. DETAILED DESCRIPTION

[0053] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0054] It should be noted that the flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor do they have to be executed in the order described. For example, some operations / steps can be decomposed, while some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0055] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0056] like Figure 1 As shown, some embodiments of the present invention disclose a method for detecting radioactive contamination of irregular materials, the method comprising the following steps:

[0057] According to the pollution type of the irregular material, a point is randomly selected from the point cloud data of the irregular material as the emission point of the ray;

[0058] A point is randomly selected from the detector end face of the detector as the detection point; the point where the line connecting the emission point and the detection point intersects with the irregular material surface is taken as the penetration point;

[0059] Repeat the extraction of emission points and detection points for a preset number of times;

[0060] The radioactive contamination of irregular materials is calculated based on the distance between the emission point and the penetration point drawn at a preset number of times and the distance between the detection point and the penetration point drawn at a preset number of times.

[0061] The detector end face refers to the face of the detector crystal facing the irregular material. Only this face can receive the rays emitted by the irregular material. The detector end face is usually a round face (high purity germanium detector, sodium iodide detector) or a square face (cadmium zinc telluride detector, plastic scintillator detector). A point is randomly selected in the detector end face as the detection point of the ray. That is, the line connecting the ray emitted from the randomly selected emission point to the randomly selected detection point on the detector end face.

[0062] In some embodiments, a point is randomly selected from the point cloud data of the irregular material according to the pollution type of the irregular material as the emission point of the ray, and the process also includes: determining the pollution type of the irregular material.

[0063] In some embodiments, determining the pollution type of the irregular material includes: determining the pollution type of the irregular material according to the pollution source item of the irregular material and the material of the irregular material.

[0064] like Figure 2 As shown, in some embodiments, the contamination type of the irregular material is determined, and then the method further includes: acquiring point cloud data of the irregular material by performing 3D scanning on the irregular material.

[0065] The irregular material is scanned 360° by the 3D laser scanning device. The rotating desktop is responsible for rotating the irregular material to ensure that the irregular material can be scanned 360° within the scanning field of view of the 3D laser scanning device. The 3D model of the irregular material can be obtained, and the 3D model can be converted into point cloud data of the irregular material, such as Figure 3 As shown, the point cloud data of irregular materials refers to a point data set composed of three-dimensional space point coordinates.

[0066] In some embodiments, irregular material contamination types include: body contamination and surface contamination.

[0067] The point cloud data of irregular materials include: irregular material voxel point cloud data and irregular material surface point cloud data. Figure 4 shown.

[0068] The pollution type of the material is mainly related to the pollution source and the material. The pollution type is divided into two types: body pollution and surface pollution. Body pollution means that the radionuclides are evenly distributed in the body of the material, and surface pollution means that the radionuclides are evenly distributed on the surface of the material. Body pollution source materials include resins, filter elements and other materials, and surface pollution source materials include metals, glass and other materials. The resins, filter elements, metals and glass here are only examples and are not limited to this application. Other materials are also possible.

[0069] In some embodiments, randomly selecting a point in the point cloud data of the irregular material according to the pollution type of the irregular material as the emission point of the ray includes:

[0070] If the irregular material pollution type is volume pollution, a point is randomly selected from the irregular material voxel point cloud data as the voxel emission point of the ray, recorded as s1(x, y, z). Specifically: If the irregular material pollution is volume pollution, a voxel point is randomly selected from the voxel point cloud data of the irregular material as the voxel emission point of the ray, and each voxel emission point is represented by a three-dimensional rectangular coordinate system, recorded as s1(x, y, z);

[0071] If the irregular material contamination type is surface contamination, a point is randomly selected from the irregular material surface point cloud data as the surface emission point of the ray, recorded as s(x, y, z).

[0072] In addition, a point is randomly selected from the detector end surface of the detector as a detection point, which is recorded as d(x, y, z).

[0073] In some embodiments, the point where the line connecting the emission point and the detection point intersects with the irregular material surface is used as the penetration point, including:

[0074] If the irregular material contamination type is volume contamination, the point where the line connecting the voxel emission point s1(x, y, z) and the detection point d(x, y, z) intersects with the surface of the irregular material is taken as the voxel penetration point t1(x, y, z).

[0075] In some embodiments, the voxel penetration point t1(x, y, z) is the intersection of the path from the voxel emission point s1(x, y, z) to the detection point d(x, y, z) and the irregular material surface;

[0076] In some other embodiments, the point in the irregular material surface point cloud data that is closest to the line connecting the voxel emission point s1 (x, y, z) to the detection point d (x, y, z) is selected as the voxel penetration point t1 (x, y, z).

[0077] If the irregular material contamination type is surface contamination, the point where the line connecting the surface emission point s(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface is taken as the surface penetration point t(x, y, z).

[0078] In some embodiments, if the irregular material contamination type is surface contamination, the point where the line connecting the surface emission point s(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface is taken as the surface penetration point t(x, y, z), including:

[0079] If the irregular material pollution type is surface pollution, determine whether the line connecting the surface emission point s(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface;

[0080] If so, the surface emission point s(x,y,z) is a surface emission point that is not within the detection range of the detector, recorded as s2(x,y,z), and the point where the line connecting the surface emission point s2(x,y,z) that is not within the detection range of the detector and the detection point d(x,y,z) intersects with the irregular material surface is taken as the surface penetration point t2(x,y,z);

[0081] If not, the surface emission point s(x, y, z) is the surface emission point within the detection range of the detector, recorded as s3(x, y, z), and there is no surface penetration point.

[0082] For irregular material surface pollution sources, there are two situations from the surface emission point s (x, y, z) to the detection point d (x, y, z). One situation is that the surface emission point is not within the detection range of the detector, and the surface emission point to the detection point needs to pass through the irregular material, and there is a penetration point; the other situation is that the surface emission point is located on one side of the detector, that is, within the detection range of the detector, and the surface emission point to the detection point does not need to pass through the irregular object, and there is no penetration point. In order to identify whether there is a penetration point, the irregular material surface point cloud data is sampled, and the point with the shortest distance from the ray path, that is, the path from the surface emission point to the detection point, is selected in the irregular material surface point cloud data. If the sampling point with the minimum distance and the surface emission point are within the preset range, there is no penetration point. Otherwise, there is a surface penetration point, and the sampled point is the surface penetration point.

[0083] like Figure 5 As shown, in some embodiments, repeatedly extracting emission points and detection points a preset number of times includes: if the irregular material pollution type is volume pollution, repeatedly extracting voxel emission points s1 (x, y, z) and detection points d (x, y, z) p times;

[0084] The radioactive contamination of the irregular material is calculated according to the distance between the emission point and the penetration point extracted for a preset number of times and the distance between the detection point and the penetration point extracted for a preset number of times, including: if the irregular material contamination type is volume contamination, the radioactive contamination ε of the irregular material volume is calculated according to the distance l1 between the voxel emission point s1(x, y, z) extracted for p times and the voxel penetration point t1(x, y, z) and the distance l'1 between the detection point d(x, y, z) extracted for p times and the voxel penetration point t1(x, y, z) V ;

[0085] Among them, the distance l1 between the voxel emission point s1(x,y,z) and the voxel penetration point t1(x,y,z) is the attenuation path of the voxel emission point ray. Within the attenuation path of the voxel emission point ray, the voxel emission point ray is attenuated by the self-absorption of the irregular material; the distance l'1 between the detection point d(x,y,z) and the voxel penetration point t1(x,y,z) is the propagation path of the voxel emission point ray. Within the propagation path of the voxel emission point ray, the absorption attenuation of the voxel emission point ray can be ignored. The attenuation path of the voxel emission point ray and the propagation path of the voxel emission point ray constitute the voxel emission point ray path.

[0086] Radioactive contamination of irregular materialsε V The calculation formula is:

[0087] Among them, μ is the linear attenuation coefficient of the material, l1 is the distance from the k-th sampled voxel emission point s1(x, y, z) to the detection point d(x, y, z), l′1 is the distance from the k-th sampled voxel emission point s1(x, y, z) to the voxel penetration point t1(x, y, z), and e is a natural constant.

[0088] like Figure 6 As shown, in some embodiments, repeatedly extracting emission points and detection points a preset number of times includes: if the irregular material contamination type is surface contamination, determining whether the surface emission point is within the detection range of the detector;

[0089] If the surface emission point is a surface emission point s2(x,y,z) that is not within the detection range of the detector, then the surface emission point s2(x,y,z) that is not within the detection range of the detector and the detection point d(x,y,z) are repeatedly sampled n times;

[0090] If the surface emission point is the surface emission point s3(x,y,z) within the detection range of the detector, then the surface emission point s3(x,y,z) and the detection point d(x,y,z) within the detection range of the detector are repeatedly sampled m times.

[0091] The radioactive contamination of irregular materials is calculated based on the distance between the emission point and the penetration point drawn at a preset number of times and the distance between the detection point and the penetration point drawn at a preset number of times, including: if the irregular material contamination type is surface contamination, determining whether the surface emission point is within the detection range of the detector;

[0092] If the surface emission point is a surface emission point s2(x,y,z) that is not within the detection range of the detector, then according to the distance l2 between the surface emission point s2(x,y,z) that is not within the detection range of the detector extracted n times and the surface penetration point t2(x,y,z) and the distance l2' between the detection point d(x,y,z) extracted n times and the voxel penetration point t2(x,y,z); and,

[0093] If the surface emission point is a surface emission point s3(x,y,z) within the detection range of the detector, then the radioactive contamination ε of the irregular material surface is calculated based on the distance l3 between the surface emission point s3(x,y,z) within the detection range of the detector extracted m times and the detection point d(x,y,z). S .

[0094] Among them, the distance l2 between the surface emission point s2(x,y,z) not within the detection range of the detector and the surface penetration point t2(x,y,z) is the attenuation path of the surface emission point ray not within the detection range of the detector. Within the attenuation path of the surface emission point ray not within the detection range of the detector, the surface emission point ray not within the detection range of the detector is attenuated by the self-absorption of the irregular material; the distance l2' between the detection point d(x,y,z) and the surface penetration point t2(x,y,z) is the propagation path of the surface emission point ray not within the detection range of the detector. Within the propagation path of the surface emission point ray not within the detection range of the detector, the absorption attenuation of the surface emission point ray not within the detection range of the detector can be ignored. The attenuation path of the surface emission point ray not within the detection range of the detector and the propagation path of the surface emission point ray not within the detection range of the detector constitute the surface emission point ray path not within the detection range of the detector.

[0095] The distance l3 between the surface emission point s3 (x, y, z) and the detection point d (x, y, z) within the detection range of the detector is the propagation path of the surface emission point ray within the detection range of the detector. Within the propagation path of the surface emission point ray within the detection range of the detector, the absorption attenuation of the surface emission point ray within the detection range of the detector can be ignored. The propagation path of the surface emission point ray within the detection range of the detector constitutes the surface emission point ray path within the detection range of the detector.

[0096] Radioactive contamination on irregular material surfacesε S The calculation formula is:

[0097] Wherein, μ is the linear attenuation coefficient of the material, l2 is the distance from the surface emission point s2(x,y,z) that is not within the detection range of the detector to the detection point d(x,y,z) of the i-th sampling, l2' is the distance from the surface emission point s2(x,y,z) that is not within the detection range of the detector to the surface penetration point t2(x,y,z) of the i-th sampling, e is a natural constant. l3 is the distance from the surface emission point s3(x,y,z) that is within the detection range of the detector to the detection point d(x,y,z) of the j-th sampling.

[0098] By implementing the present invention, the following beneficial effects are achieved:

[0099] The present invention randomly extracts a point in the point cloud data of the irregular material according to the pollution type of the irregular material as the emission point of the ray; randomly extracts a point in the detector end face of the detector as the detection point; uses the point where the line connecting the emission point and the detection point intersects with the surface of the irregular material as the penetration point; repeatedly extracts the emission point and the detection point for a preset number of times; calculates the radioactive contamination of the irregular material according to the distance between the emission point and the penetration point extracted for the preset number of times and the distance between the detection point and the penetration point extracted for the preset number of times, thereby realizing the calculation of the radioactive contamination of large-volume irregular materials and eliminating the problems of the current method that a calibration source needs to be formulated according to the material medium or the technical requirements for the implementers are high, the simulation calculation time is long, and the method is not easy to transplant.

[0100] It is understandable that the above embodiments only express some implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present invention, the above embodiments or technical features can be freely combined, and several deformations and improvements can be made, which all belong to the protection scope of the present invention, that is, the embodiments described in "some embodiments" can be freely combined with any of the above and below embodiments. Therefore, all equivalent changes and modifications made to the scope of the claims of the present invention should belong to the scope of the claims of the present invention.

Claims

1. A method for detecting radioactive contamination of irregular materials, characterized in that: The method comprises the following steps: According to the pollution type of the irregular material, a point is randomly selected from the point cloud data of the irregular material as the emission point of the ray; A point is randomly selected within the detector end face of the detector as a detection point; The point where the line connecting the emission point and the detection point intersects with the irregular material surface is taken as the penetration point; Repeat the extraction of emission points and detection points for a preset number of times; The radioactive contamination of irregular materials is calculated based on the distance between the emission point and the penetration point drawn at a preset number of times and the distance between the detection point and the penetration point drawn at a preset number of times.

2. The method for detecting radioactive contamination of irregular materials according to claim 1, characterized in that: According to the pollution type of the irregular material, a point is randomly selected from the point cloud data of the irregular material as the emission point of the ray, which also includes: Determine the contamination type of irregular materials.

3. The method for detecting radioactive contamination of irregular materials according to claim 2, characterized in that: Determine the type of contamination of irregular materials, including: Determine the irregular material pollution type based on the irregular material pollution source items and irregular material materials.

4. The method for detecting radioactive contamination of irregular materials according to claim 2, characterized in that: Determine the type of irregular material contamination, and then include: By performing 3D scanning on irregular materials, point cloud data of irregular materials can be obtained.

5. The method for detecting radioactive contamination of irregular materials according to claim 3 or 4, characterized in that: Irregular material contamination types include: body contamination and surface contamination; The point cloud data of irregular materials include: irregular material voxel point cloud data and irregular material surface point cloud data.

6. The method for detecting radioactive contamination of irregular materials according to claim 1, characterized in that: According to the pollution type of the irregular material, a point is randomly selected from the point cloud data of the irregular material as the emission point of the ray, including: If the irregular material pollution type is volume pollution, a point is randomly selected from the irregular material voxel point cloud data as the voxel emission point of the ray, recorded as s1(x, y, z); If the irregular material contamination type is surface contamination, a point is randomly selected from the irregular material surface point cloud data as the surface emission point of the ray, recorded as s(x, y, z); And, the detection point is recorded as d(x,y,z).

7. The method for detecting radioactive contamination of irregular materials according to claim 1, characterized in that: The point where the line connecting the emission point and the detection point intersects with the irregular material surface is taken as the penetration point, including: If the irregular material contamination type is volume contamination, the point where the line connecting the voxel emission point s1(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface is taken as the voxel penetration point t1(x, y, z); If the irregular material contamination type is surface contamination, the point where the line connecting the surface emission point s(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface is taken as the surface penetration point t(x, y, z).

8. The method for detecting radioactive contamination of irregular materials according to claim 7, characterized in that: If the irregular material pollution type is surface pollution, the point where the line connecting the surface emission point s(x,y,z) and the detection point d(x,y,z) intersects with the irregular material surface is taken as the surface penetration point t(x,y,z), including: If the irregular material pollution type is surface pollution, determine whether the line connecting the surface emission point s(x, y, z) and the detection point d(x, y, z) intersects with the irregular material surface; If so, the surface emission point s(x,y,z) is a surface emission point that is not within the detection range of the detector, recorded as s2(x,y,z), and the point where the line connecting the surface emission point s2(x,y,z) that is not within the detection range of the detector and the detection point d(x,y,z) intersects with the irregular material surface is taken as the surface penetration point t2(x,y,z); If not, the surface emission point s(x, y, z) is the surface emission point within the detection range of the detector, recorded as s3(x, y, z), and there is no surface penetration point.

9. The method for detecting radioactive contamination of irregular materials according to claim 6, characterized in that: Repeating the extraction of emission points and detection points for a preset number of times, including: if the irregular material contamination type is volume contamination, then repeatedly extracting voxel emission points s1(x, y, z) and detection points d(x, y, z) p times; The radioactive contamination of the irregular material is calculated according to the distance between the emission point and the penetration point extracted for a preset number of times and the distance between the detection point and the penetration point extracted for a preset number of times, including: if the irregular material contamination type is volume contamination, the radioactive contamination ε of the irregular material volume is calculated according to the distance l1 between the voxel emission point s1(x, y, z) extracted for p times and the voxel penetration point t1(x, y, z) and the distance l1' between the detection point d(x, y, z) extracted for p times and the voxel penetration point t1(x, y, z) V ; Radioactive contamination of irregular materialsε V The calculation formula is: Among them, μ is the linear attenuation coefficient of the material, l1 is the distance from the k-th sampling voxel emission point s1(x,y,z) to the detection point d(x,y,z), and l1' is the distance from the k-th sampling voxel emission point s1(x,y,z) to the voxel penetration point t1(x,y,z).

10. The method for detecting radioactive contamination of irregular materials according to claim 6, characterized in that: Repeated extraction of emission points and detection points for a preset number of times, including: if the irregular material contamination type is surface contamination, determining whether the surface emission point is within the detection range of the detector; If the surface emission point is a surface emission point s2(x,y,z) that is not within the detection range of the detector, then the surface emission point s2(x,y,z) that is not within the detection range of the detector and the detection point d(x,y,z) are repeatedly sampled n times; If the surface emission point is the surface emission point s3(x,y,z) within the detection range of the detector, then the surface emission point s3(x,y,z) and the detection point d(x,y,z) within the detection range of the detector are repeatedly sampled m times; The radioactive contamination of irregular materials is calculated based on the distance between the emission point and the penetration point drawn at a preset number of times and the distance between the detection point and the penetration point drawn at a preset number of times, including: if the irregular material contamination type is surface contamination, determining whether the surface emission point is within the detection range of the detector; If the surface emission point is a surface emission point s2(x,y,z) that is not within the detection range of the detector, then according to the distance l2 between the surface emission point s2(x,y,z) that is not within the detection range of the detector and the surface penetration point t2(x,y,z) extracted n times and the distance l2' between the detection point d(x,y,z) extracted n times and the surface penetration point t2(x,y,z); and, If the surface emission point is a surface emission point s3(x, y, z) within the detection range of the detector, then the radioactive contamination ε of the irregular material surface is calculated based on the distance l3 between the surface emission point s3(x, y, z) within the detection range of the detector extracted m times and the detection point d(x, y, z). S ; Radioactive contamination on irregular material surfacesε S The calculation formula is: Wherein, μ is the linear attenuation coefficient of the material, l2 is the distance from the surface emission point s2(x,y,z) that is not within the detection range of the detector to the detection point d(x,y,z) of the i-th sampling, and l2' is the distance from the surface emission point s2(x,y,z) that is not within the detection range of the detector to the surface penetration point t2(x,y,z) of the i-th sampling; l3 is the distance from the surface emission point s3(x,y,z) to the detection point d(x,y,z) within the detection range of the detector for the jth sampling.

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