Turbine blade internal structure identification method and system

Abstract

The invention discloses a method and system for identifying the internal structure of a turbine blade, and relates to the technical field of identification of the internal structure of a hollow turbine blade of a gas turbine, and the method comprises the following steps: firstly, obtaining a DR image of the initial state of the turbine blade, and enabling a tangent line formed by the front edge and the rear edge of the concave side of the blade in the initial state to be perpendicular to a ray beam outgoing direction; then taking tomography sectional views at two positions along the height direction of the blade, identifying the cooling channels and constructing a midpoint connecting line of midpoints of the cooling channels at the same position; rotating the blade until the horizontal projections of the two end points of the midpoint connecting line coincide to form a point P, and acquiring a vertical line passing through the point P and between the angle bisectors of the horizontal projection lines of the two midpoint connecting line; and finally, rotating the blade to enable the vertical line to be parallel to the ray beam outgoing direction, and obtaining a DR image in the state to identify the internal structure. The method does not need a large amount of tomography, can accurately align the detection angle, gives consideration to the recognition precision and efficiency, reduces the detection cost, and is suitable for the rapid and accurate recognition of the internal structure and damage of the turbine blade.

Description

Technical Field

[0001] This invention relates to the field of internal structure identification technology for hollow turbine blades of gas turbines, specifically to a method and system for identifying the internal structure of turbine blades. Background Technology

[0002] Turbine blades, as core hot-end components of turbine machinery such as gas turbines and steam turbines, are key carriers for converting fluid thermal and pressure energy into mechanical kinetic energy. Their performance directly determines the operating efficiency, reliability, and service life of turbine machinery. With the trend of turbine machinery developing towards higher parameters (high temperature, high pressure) and longer operating cycles, turbine blades need to withstand extreme high temperatures of 600-1600℃, high pressures of tens of megapascals, high-speed airflow scouring, and alternating thermal stress loads for extended periods. To solve their heat dissipation problems, the industry generally adopts a hollow structure design, integrating multiple complex cooling channels (such as serpentine channels, turbulence column channels, and impact cooling channels) inside the blade. Heat exchange is achieved through the flow of cooling media, ensuring the structural integrity of the blade under extreme operating conditions.

[0003] Currently, the detection and identification of the internal cooling structure of turbine blades is a core aspect of ensuring the safe operation of turbine machinery. On the one hand, during the blade manufacturing process, problems such as casting defects and welding deviations may cause blockages in cooling channels and uneven diaphragm wall thickness, directly affecting heat dissipation efficiency. On the other hand, after long-term service, blades are prone to damage such as corrosion, cracks, and scale buildup on the inner walls of the cooling channels, which may lead to blade overheating failure or even turbine unit shutdown accidents. Therefore, accurate identification of the structural morphology, dimensional accuracy, and damage status of the internal cooling channels of turbine blades is a key requirement for quality inspection, operation, and maintenance in turbine machinery manufacturing.

[0004] Traditional nondestructive testing techniques lack precision. Traditional methods such as ultrasonic testing and eddy current testing can only locate macroscopic defects and cannot clearly present the complex geometry of cooling channels (such as channel cross-sectional dimensions, baffle distribution, and the location of turbulence structures). Furthermore, they are weak in identifying minute problems such as microcracks and local blockages in channels. Although radiographic testing (RT) can generate two-dimensional projection images, it is easily affected by the complex structure of the blades, resulting in image overlap and blurred details. It is difficult to distinguish the boundaries of adjacent cooling channels and cannot meet the requirements for high-precision identification.

[0005] With the development of high-end equipment such as heavy-duty gas turbines and supercritical carbon dioxide turbines, the internal cooling structures of turbine blades are becoming increasingly complex (such as multi-branch channels and variable cross-section channel designs), placing higher demands on the accuracy, efficiency, and compatibility of internal structure identification. Therefore, developing a method for identifying the internal structure of turbine blades that can achieve accurate multi-angle adaptation, speed, efficiency, and low cost, and addressing the pain points of "insufficient accuracy, low efficiency, and distortion of details" in existing technologies, has become a key technological requirement for promoting the high-end development of turbine machinery. Summary of the Invention

[0006] To address the problems existing in the prior art, the present invention provides a method and system for identifying the internal structure of turbine blades, enabling rapid and accurate identification of the internal structure of turbine blades.

[0007] This invention is achieved through the following technical solution: In a first aspect, this application provides a method for identifying the internal structure of a turbine blade, comprising the following steps: Step 1: Obtain DR images of the turbine blades in their initial state; In the initial state, the tangent formed by the leading and trailing edges of the concave side of the turbine blade is perpendicular to the direction of the ray beam exit. Step 2: Obtain cross-sectional images of two locations along the height direction of the blade based on the DR image; Step 3: Identify the cooling channels based on the tomographic scan cross-section diagrams, and construct a midpoint connection line based on the midpoints of the cooling channels at the same location in the two tomographic scan cross-section diagrams; Step 4: Rotate the turbine blade until the two endpoints of the midpoint connecting line coincide in the horizontal projection direction to form point P; Step 5: Obtain the perpendicular line to the angle bisector of the horizontal projection line of the line connecting the two midpoints, and this perpendicular line passes through point P; Step 6: Rotate the turbine blade so that the vertical line is parallel to the direction of the ray beam, and obtain a DR image of the turbine blade in this state to identify the internal structure of the turbine blade.

[0008] Preferably, the method for obtaining the DR image of the turbine blade in its initial state is as follows: Connect the turbine blade tenon to the clamping fixture, connect the clamping fixture to the turntable, the clamping fixture 2 is used to adjust the tilt angle of the turbine blade, and the turntable is used to adjust the rotation angle of the turbine blade. The turbine blade is held vertically by clamping fixture 2, and then the rotation angle of the blade is adjusted by turntable so that the tangent from the leading edge to the trailing edge of the concave side in the height direction of the turbine blade is perpendicular to the beam exit direction. Obtain the DR image of the turbine blade in this state, that is, the DR image of the turbine blade in its initial state.

[0009] Preferably, the blade tenon of the turbine blade is connected to the clamping fixture through a groove structure.

[0010] Preferably, the step of obtaining tomographic cross-sectional images at two locations along the height direction of the blade based on the DR image includes: The turbine blade is divided into multiple regions along the leaf height direction using DR images. At least two tomographic cross-sectional images were acquired for each region.

[0011] Preferably, the method for identifying cooling channels based on tomographic cross-sectional images and constructing a midpoint connecting line based on the midpoints of cooling channels at the same location in any two tomographic cross-sectional images is as follows: Obtain the baffles at the front and rear edges of the cooling channel, determine the midpoints of the opposite faces of the two baffles, and construct a straight line based on the midpoints of the two baffles; Determine the midpoints of two straight lines, and then construct a line connecting the midpoints.

[0012] Preferably, the method for rotating the turbine blade until the two endpoints of the midpoint connecting line coincide in the horizontal projection direction to form point P is as follows: The rotation and tilt angles of the turbine blades are adjusted. During the adjustment process, the two straight lines and the line connecting the midpoints are projected onto a plane. The two endpoints of the line connecting the midpoints are determined based on the projection lines. When the endpoints coincide, the coincident point is taken as point P. At the same time, the two straight lines form an angle line along point P.

[0013] Preferably, the method for obtaining the perpendicular line to the angle bisector of the horizontal projection line of the line connecting the two midpoints is as follows: First, draw the angle bisector of the included angle line through point P. Finally, draw the perpendicular line from point P to the angle bisector.

[0014] Preferably, the method for rotating the turbine blade so that the vertical line is parallel to the beam exit direction, acquiring a DR image of the turbine blade in this state, and then identifying the internal structure of the turbine blade is as follows: The rotation angle of the turbine blade is controlled so that the vertical line rotates until it is parallel to the rays emitted by the industrial CT scanner. Then, a DR image of the turbine blade is re-captured, and the internal structure and damage structure of the turbine blade are identified based on the DR image.

[0015] Preferably, the radiation emitted by the industrial CT is X-ray or gamma-ray.

[0016] Secondly, this application provides a system for identifying the internal structure of a turbine blade, comprising: The acquisition modulus is used to obtain DR images of the turbine blade in its initial state; In the initial state, the tangent formed by the leading and trailing edges of the concave side of the turbine blade is perpendicular to the direction of the ray beam exit. The scanning module is used to obtain cross-sectional images of two locations along the height direction of the blade based on the DR image; The channel module is used to identify cooling channels based on tomographic cross-sectional images and to construct a midpoint connection line based on the midpoint of the cooling channels at the same location in two tomographic cross-sectional images. The first auxiliary line module is used to rotate the turbine blade until the two endpoints of the midpoint connecting line coincide in the horizontal projection direction to form point P. The second auxiliary line module is used to draw the perpendicular line to the angle bisector of the horizontal projection line of the line connecting the two midpoints, and this perpendicular line passes through point P. The identification module is used to rotate the turbine blade so that the vertical line is parallel to the direction of the ray beam, acquire a DR image of the turbine blade in this state, and then identify the internal structure of the turbine blade.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects: This application provides a method for identifying the internal structure of turbine blades. By aligning the tangents of the leading and trailing edges of the concave side of the turbine blade perpendicular to the beam emission direction, a stable benchmark is established for subsequent tomographic scanning, avoiding initial imaging deviations that could affect the accuracy of structural identification. Precise adjustment of the blade's spatial attitude is achieved through the alignment of the connecting line at the midpoint of the cooling channel and the projected coincidence, allowing for targeted alignment of the relative positions of the internal cooling channels and the detection beam, thus solving the imaging blurring problem caused by channel tilting or bending in traditional detection methods. Parallel calibration of the angle bisector perpendicular to the beam emission direction ensures that the final DR image clearly presents the cooling channels and internal structural details. Accurate structural information can be obtained without numerous tomographic scans, significantly reducing detection time and cost while maintaining identification accuracy. This method balances accuracy and efficiency, is applicable to the detection of turbine blades with different blade shapes and cooling channel layouts, and demonstrates strong practicality and compatibility. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the blade being measured and the clamping fixture of the present invention.

[0020] Figure 2 This is a schematic diagram of the rotating device and turntable of the present invention.

[0021] Figure 3 This is a schematic diagram of industrial CT measurement of the blade being measured according to the present invention.

[0022] Figure 4 These are the internal structural features identified by the initial tomographic scan of the leaf root region in this invention.

[0023] Figure 5 These are the internal structural features identified by the initial tomographic scan near the top of the blade in this invention.

[0024] Figure 6 This is a schematic diagram of auxiliary lines within the same cooling channel of the present invention.

[0025] Figure 7 This is a schematic diagram showing the midpoints of the two auxiliary lines of the present invention coinciding.

[0026] Figure 8 This is a schematic diagram of the cooling channel of the present invention facing the direction of the X-ray beam exit.

[0027] In the diagram: 1. Turbine blade being measured; 2. Clamping fixture; 3. Rotating device; 4. Turntable; 5. Blade tenon; 6. Industrial CT control system; 7. Beam output device; 8. Receiving device; 10. Blade area; 22. Lower area; 21. Upper area 101. First zone; 102. Second zone; 103. Blade tip section; 104. Blade root section; 105. Hollow region; 106. Partition wall; 107. Partition wall; 108. Hollow region; 109. Partition wall; 110. Partition wall; 111. Straight line; 112. Straight line; 113. Midpoint connection line; 114. Angle bisector; 115. Perpendicular line. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0030] First, the turbine blades and related terms are defined as follows: The blade tenon is a key structure connecting the turbine blade and the rotor disk. It is usually located at the root of the blade (blade root) and has a tooth-like protrusion. Its core function is to achieve precise positioning and a firm connection between the blade and the disk, ensuring that the blade does not shift or fall off during high-speed rotation.

[0031] During installation, the blade tenons need to be precisely matched with the tenons on the wheel (such as the clamping fixture area 21 above the blade tenons 5 in the document to clamp the blade). At the same time, it needs to transmit the torque and axial force generated when the blade is working. Therefore, it has extremely high requirements for its dimensional accuracy, surface finish and material strength. Common tenon structure forms include fir tree type, T type, dovetail type, etc.

[0032] The leading edge is the blade edge that first contacts the high-speed airflow during turbine operation, and it is usually designed with an arc or streamlined shape. Its main function is to guide the airflow smoothly into the blade passage, reduce airflow impact losses, and lower aerodynamic drag. At the same time, it must withstand the scouring of impurities in the airflow and the thermal load of the highest temperature.

[0033] The trailing edge is the edge on the side of the turbine blade where the airflow exits. It is usually a thin, straight or slightly curved structure located in the gap between the blade and the adjacent blade on the exit side. Its function is to ensure that the airflow completes energy conversion within the blade passage and flows smoothly out of the blade, reducing airflow wake loss and aerodynamic noise.

[0034] The blade tip is the top region of a turbine blade along its height, that is, the end furthest from the blade root (blade root) and closest to the turbine casing. There is usually a small gap (blade tip clearance) between the blade tip and the inner wall of the casing. Its main function is to reduce airflow leakage from the high-pressure side of the blade to the low-pressure side through the blade tip clearance, thereby reducing leakage losses and improving turbine efficiency.

[0035] The blade root is the region where the turbine blade connects to the turbine rotor disk. Located at the lower end of the blade along its height, it is a critical part for transmitting torque and bearing loads. The blade root integrates the blade tenon structure (as shown in the document, blade tenon 5 is located in the blade root region). It fixes the blade by cooperating with the disk tenon groove, and must withstand complex loads such as centrifugal force, aerodynamic force, and thermal stress during blade operation.

[0036] DR images, or "digital radiography images," are two-dimensional projection images based on industrial X-ray inspection technology. X-rays or gamma rays are emitted from an X-ray emitter toward the object being tested (such as a turbine blade). As the rays penetrate the object, they are attenuated to varying degrees due to differences in material density and thickness at different locations. The attenuated rays are captured by a receiving device (such as a flat panel detector) and converted into digital signals, which are then processed by a computer to generate a visualized image.

[0037] The beam direction refers to the direction of propagation of the detection rays emitted by the X-ray source (beam emitter) in an industrial CT (computed tomography) device. It is one of the core parameters for industrial CT to achieve tomographic scanning and DR (digital radiography) imaging.

[0038] A method for identifying the internal structure of a turbine blade includes the following steps: Step 1: Obtain DR images of the turbine blades in their initial state; In this initial state, the tangent formed by the leading and trailing edges of the concave side of the turbine blade is perpendicular to the direction of the ray beam exit; By precisely setting the initial blade orientation, ensuring that the tangent formed by the leading and trailing edges of the concave side of the blade is perpendicular to the beam exit direction, the occlusion and overlap of the blade structure during initial imaging can be minimized, ensuring that the initial DR image clearly presents the overall outline of the blade and the distribution of the blade area. This eliminates the need for repeated adjustments to the initial orientation, avoiding subsequent detection errors caused by initial imaging deviations, and provides an accurate image reference for selecting the tomographic scanning position along the blade height direction.

[0039] Step 2: Obtain cross-sectional images of two locations along the height direction of the blade based on the DR image; Based on the blade outline and height distribution of the initial DR image, two height locations are selectively chosen for tomographic scanning. This allows for focusing on the structural features of the internal cooling channels at different heights. The cooling channels often exhibit size and morphological variations along the blade height, and the scanning data from these two sections can preliminarily reflect the spatial distribution patterns of these channels. This eliminates the need for intensive scanning of the entire blade height, significantly reducing the number of scans and lowering inspection time and equipment wear while ensuring the acquisition of crucial structural information.

[0040] Step 3: Identify the cooling channels based on the tomographic scan cross-section diagrams, and construct a midpoint connection line based on the midpoints of the cooling channels at the same location in the two tomographic scan cross-section diagrams; By utilizing the density difference between the cooling channel and the blade matrix in the tomographic cross-section, the boundaries of the cooling channel and the internal baffle structure can be accurately identified. By determining the midpoint of the same cooling channel in two cross-sections and connecting them, the spatial position of the cooling channel can be transformed into a visual straight-line reference, reflecting the spatial orientation of the cooling channel. The core axis of the cooling channel can be accurately located by connecting the midpoints, providing a clear structural benchmark for subsequent attitude adjustments and avoiding positioning deviations caused by the complexity of the cooling channel structure.

[0041] Step 4: Rotate the turbine blade until the two endpoints of the midpoint connecting line coincide in the horizontal projection direction to form point P; By rotating the blades to adjust their spatial attitude, the horizontal projection of the line connecting the midpoints of the cooling channel is reduced from a "line" to a "point (P point)". At this point, the blade attitude ensures that the spatial orientation of the cooling channel is perpendicular to the horizontal projection plane, eliminating the offset error of the cooling channel in the projection direction. With the intuitive judgment method of projection coincidence, the blade attitude can be quickly calibrated without complex spatial coordinate calculations, aligning the spatial position of the cooling channel with the detection reference.

[0042] Step 5: Draw the angle bisector of the horizontal projection line of the line connecting the two midpoints through point P, and then draw the perpendicular line from point P to the angle bisector. Find the symmetrical midline of the included angle by using the angle bisector, and then draw a perpendicular line to the bisector. This perpendicular line precisely corresponds to the core symmetry plane of the cooling channel. Cooling channels are mostly designed with symmetrical structures, and the direction of the perpendicular line is exactly consistent with the direction of the critical section of the cooling channel. Through simple geometric construction, the key reference line matching the cooling channel structure can be determined.

[0043] Step 6: Rotate the turbine blade so that the vertical line is parallel to the direction of the ray beam, and obtain a DR image of the turbine blade in this state to identify the internal structure of the turbine blade.

[0044] When the vertical line is parallel to the direction of the ray beam, the ray can penetrate the blade along the key cross-section of the cooling channel. At this time, the DR image can clearly show the inner wall, baffles, turbulence structure and possible damage (such as cracks and blockages) of the cooling channel, avoiding the blurring of details caused by the mismatch between the ray direction and the channel structure.

[0045] In some embodiments, the method for obtaining a DR image of the turbine blade in its initial state is as follows: Connect the blade tenon of the turbine blade to the clamping fixture 2. The clamping fixture 2 is connected to the turntable. The clamping fixture 2 is used to adjust the tilt angle of the turbine blade, and the turntable is used to adjust the rotation angle of the turbine blade.

[0046] The turbine blade is held vertically by clamping fixture 2. Then, the rotation angle of the blade is adjusted by turntable so that the tangent from the leading edge to the trailing edge of the concave side in the height direction of the turbine blade is perpendicular to the beam output direction of the industrial CT. Obtain a DR image of the turbine blade in this state, which represents the initial position of the turbine blade.

[0047] In some embodiments, tomographic cross-sectional images at two locations are obtained from the DR image along the height direction of the blade; The DR image is used to divide the blade region 10 of the turbine blade 1 into at least two regions along the blade height direction, and at least two tomographic cross-sectional images are obtained for each region.

[0048] Obtain cross-sectional images of the upper and lower parts of each region using tomographic scanning.

[0049] In some embodiments, cooling channels are identified based on tomographic cross-sectional images, and a midpoint connection line is constructed based on the midpoints of cooling channels at the same location in two tomographic cross-sectional images. Obtain the baffles at the front and rear edges of the cooling channel, determine the midpoints of the opposite faces of the two baffles, and construct a straight line based on the midpoints of the two baffles; perform the same operation on the two tomographic scan cross-sections.

[0050] Determine the midpoints of two straight lines, and then construct a line connecting the midpoints.

[0051] It should be noted that for any given region, multiple tomographic scan cross-sections can be scanned, and any two tomographic scan cross-sections can be selected to identify cooling channels, thereby constructing a midpoint connection line.

[0052] In some embodiments, the turbine blade is rotated until the two endpoints of the midpoint connecting line coincide in the horizontal projection direction to form point P, as follows: The synchronous control turntable and clamping fixture 2 are used to adjust the rotation angle and tilt angle of the turbine blade. During the adjustment process, the two straight lines and the midpoint connecting line are projected onto a plane. The two endpoints of the midpoint connecting line are determined according to the projection line. When the endpoints coincide, the coincident point is taken as point P. At the same time, the two straight lines form an angle line along point P.

[0053] Then, draw the angle bisector of the included angle, and finally, draw the perpendicular line from point P to the angle bisector.

[0054] In some embodiments, the turbine blade is rotated so that the vertical line is parallel to the direction of the ray beam exit, and a DR image of the turbine blade in this state is acquired. The method for identifying the internal structure of the turbine blade is as follows: The rotation angle of the turntable is controlled so that the vertical line rotates until it is parallel to the rays emitted by the industrial CT scanner. Then, a DR image of the turbine blade is re-captured, and the internal structure and damage structure of the turbine blade are identified based on the DR image.

[0055] Example 1 See Figure 1-8 A method for identifying the internal structure of a turbine blade, comprising the following steps: S1: The turbine blade 1 to be measured is mounted on the clamping fixture 2. The clamping fixture 2 has two parts, upper and lower. The upper area 21 cooperates with the blade tenon 5 to clamp the blade. The lower area 22 is connected to the rotating device 3. The rotating device 3 is fixedly connected to the turntable 4 of the industrial CT. The rotation angle of the rotating device 3 is controlled by the computer 6 of the industrial CT control system and works in conjunction with the turntable.

[0056] See Figure 2 It should be noted that the turntable 4 can drive the clamping fixture 2 to select 360° axially, and can also adjust the tilt angle of the turbine blade through the clamping fixture 2, that is, the turntable has two rotational dimensions.

[0057] S2: Take a DR image of a turbine blade using an industrial CT device. The initial placement of the blade is such that the middle of the blade is approximately directly opposite the beam output direction of the X-ray beam output device 7. The beam output device 7 and the receiving device 8 are located on both sides of the turbine blade.

[0058] See Figure 3Initial position: The tangent from the leading edge to the trailing edge of the concave side of the blade is perpendicular to the direction of the ray exit.

[0059] S3: On the captured DR image, the blade region 10 of the turbine blade 1 is divided into at least a first section 101 and a second section 102 along the blade height direction. Each region is subjected to a tomographic scan of the upper and lower height sections along the blade height direction, such as the section 103 near the top of the blade and the section 104 near the root of the blade in the first region from top to bottom.

[0060] This can also be understood as performing two tomographic scans in each partition, that is, in the upper and lower parts of each partition, resulting in two tomographic cross-sectional images for each partition.

[0061] S4: Identify the internal structural features of the two tomographic cross-sectional images.

[0062] S5: For the identified blade tip section 103 and the section near the blade root 104, which share the same internal cooling channel, the cooling channel has hollow areas 105 and 108 of its respective cross-section channel, baffle wall surfaces 106 and 109 near the front of the blade, and baffle wall surfaces 107 and 110 near the rear of the blade. Take the midpoint of the line segment near the front of the baffle wall and the midpoint of the line segment near the rear of the baffle wall of the same cross-section and connect them to obtain straight lines 111 and 112. Take the midpoint of straight lines 111 and 112 and connect them to obtain straight line 113.

[0063] The cooling channels inside the blade extend from the blade root to the blade tip. The number of cooling channels remains constant in each cross-sectional image, only the cross-sectional size of the cooling channels varies between different cross-sections. For the same cooling channel in two cross-sections, the midpoints of the baffle surfaces in the directions of the leading and trailing edges of the cooling channel in each cross-section are identified. Connecting these two midpoints forms a straight line. Connecting the midpoints of the two straight lines yields line 113.

[0064] S6: Operate the industrial CT control system 6 to rotate the measured turbine blade 1 linear 113 so that the midpoints of linear 111 and 112 coincide, and the point of coincidence of linear 111 and 112 is P.

[0065] During the rotation, the turntable is controlled to rotate while the tilt angle of the blades is adjusted so that the two endpoints of line 113 rotate until they coincide in the horizontal projection direction, that is, the midpoints of lines 111 and 112 coincide to form point P.

[0066] S7: Obtain the horizontal projection lines of lines 111 and 112. Based on the angle between the horizontal projection lines of lines 111 and 112, construct the angle bisector 114 of the angle. That is, construct the angle bisector of the angle through point P. Finally, construct the perpendicular line 115 from point P to the angle bisector 114.

[0067] S8: Operate the industrial CT control system 6 to rotate the turbine blade 1 being measured until the vertical line 115 is parallel to the beam output direction of the industrial CT beam output device 7.

[0068] S9: Take a DR image from this angle, and identify the internal structure and defects of the turbine blade 1 under test based on the DR image.

[0069] The above description uses the first partition 101 near the top of the turbine blade as an example to illustrate the method proposed in this invention. When actually measuring the blade, at least two partitions are measured; the measurement method for other cooling channels is the same. Correspondingly, this application also provides a turbine blade internal structure identification system, including: The acquisition modulus is used to obtain DR images of the turbine blade in its initial state; In the initial state, the tangent formed by the leading and trailing edges of the concave side of the turbine blade is perpendicular to the direction of the ray beam exit. The scanning module is used to obtain cross-sectional images of two locations along the height direction of the blade based on the DR image; The channel module is used to identify cooling channels based on tomographic cross-sectional images and to construct a midpoint connection line based on the midpoint of the cooling channels at the same location in two tomographic cross-sectional images. The first auxiliary line module is used to rotate the turbine blade until the two endpoints of the midpoint connecting line coincide in the horizontal projection direction to form point P. The second auxiliary line module is used to draw the perpendicular line to the angle bisector of the horizontal projection line of the line connecting the two midpoints, and this perpendicular line passes through point P. The identification module is used to rotate the turbine blade so that the vertical line is parallel to the direction of the ray beam, acquire a DR image of the turbine blade in this state, and then identify the internal structure of the turbine blade.

[0070] The method in this embodiment uses multi-angle imaging of the internal structure of each channel of a turbine blade with a complex internal cooling structure to quickly and accurately identify the surface disturbance structure of the inner arc side and back arc side of the internal channel. It can identify the internal cooling structure of the blade based on a small number of industrial CT images, without the need for a large number of industrial CT tomographic scans of the same blade, which can significantly save detection costs.

[0071] It should be noted that, in the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules may be combined or integrated into another device, or some features may be ignored or not executed. The modules described as separate components may or may not be physically separated. The components shown as modules may be one or more physical units, that is, they may be located in one place or distributed in multiple different places. Some or all of the modules can be selected to achieve the purpose of the solution in this embodiment according to actual needs.

[0072] Furthermore, in the various embodiments of the present invention, the modules can be integrated into one processing unit, or each module can exist physically separately, or two or more modules can be integrated into one unit. The integrated unit described above can be implemented in hardware or as a software functional unit.

[0073] An electronic device provided in this application includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the steps of the method for identifying the internal structure of a turbine blade as described in any of the above embodiments.

[0074] Another electronic device provided in this application embodiment may further include: an input port connected to a processor for transmitting multimodal data collected by an external acquisition device to the processor; a display unit connected to the processor for displaying the processor's processing results to the outside world; and a communication module connected to the processor for enabling communication between the electronic device and the outside world. The display unit may be a display panel, a laser scanning display, etc.; the communication method adopted by the communication module includes, but is not limited to, Mobile High Definition Link (HML), Universal Serial Bus (USB), High Definition Multimedia Interface (HDMI), and wireless connection (including Wi-Fi, Bluetooth, Bluetooth Low Energy, and IEEE 802.11s-based communication technology).

[0075] This application provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the steps of the turbine blade internal structure identification method described in any of the above embodiments.

[0076] For descriptions of relevant parts of the turbine blade internal structure identification system, electronic device, and computer-readable storage medium provided in this application's embodiments, please refer to the detailed descriptions of the corresponding parts in the turbine blade internal structure identification method provided in this application's embodiments; they will not be repeated here. Furthermore, parts of the technical solutions provided in this application that are consistent with the implementation principles of corresponding technical solutions in the prior art have not been described in detail to avoid excessive elaboration.

[0077] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for identifying the internal structure of a turbine blade, characterized in that, Includes the following steps: Step 1: Obtain DR images of the turbine blades in their initial state; In the initial state, the tangent formed by the leading and trailing edges of the concave side of the turbine blade is perpendicular to the direction of the ray beam exit. Step 2: Obtain cross-sectional images of two locations along the height direction of the blade based on the DR image; Step 3: Identify the cooling channels based on the tomographic scan cross-section diagrams, and construct a midpoint connection line based on the midpoints of the cooling channels at the same location in the two tomographic scan cross-section diagrams; Step 4: Rotate the turbine blade until the two endpoints of the midpoint connecting line coincide in the horizontal projection direction to form point P; Step 5: Obtain the perpendicular line to the angle bisector of the horizontal projection line of the line connecting the two midpoints, and this perpendicular line passes through point P; Step 6: Rotate the turbine blade so that the vertical line is parallel to the direction of the ray beam, and obtain a DR image of the turbine blade in this state to identify the internal structure of the turbine blade.

2. The method for identifying the internal structure of a turbine blade according to claim 1, characterized in that, The method for obtaining the DR image of the turbine blade in its initial state is as follows: Connect the turbine blade tenon to the clamping fixture, connect the clamping fixture to the turntable, the clamping fixture 2 is used to adjust the tilt angle of the turbine blade, and the turntable is used to adjust the rotation angle of the turbine blade. The turbine blade is held vertically by clamping fixture 2, and then the rotation angle of the blade is adjusted by turntable so that the tangent from the leading edge to the trailing edge of the concave side in the height direction of the turbine blade is perpendicular to the beam exit direction. Obtain the DR image of the turbine blade in this state, that is, the DR image of the turbine blade in its initial state.

3. The method for identifying the internal structure of a turbine blade according to claim 1, characterized in that, The blade tenon and the clamping fixture are connected by a groove structure.

4. The method for identifying the internal structure of a turbine blade according to claim 1, characterized in that, The step of obtaining tomographic cross-sectional images at two locations along the height direction of the blade based on the DR image includes: The turbine blade is divided into multiple regions along the leaf height direction using DR images. At least two tomographic cross-sectional images were acquired for each region.

5. The method for identifying the internal structure of a turbine blade according to claim 4, characterized in that, The method for identifying cooling channels based on tomographic cross-sectional images and constructing a midpoint connection line based on the midpoints of cooling channels at the same location in any two tomographic cross-sectional images is as follows: Obtain the baffles at the front and rear edges of the cooling channel, determine the midpoints of the opposite faces of the two baffles, and construct a straight line based on the midpoints of the two baffles; Determine the midpoints of two straight lines, and then construct a line connecting the midpoints.

6. The method for identifying the internal structure of a turbine blade according to claim 1, characterized in that, The method for rotating the turbine blade until the two endpoints of the midpoint connecting line coincide in the horizontal projection direction to form point P is as follows: The rotation and tilt angles of the turbine blades are adjusted. During the adjustment process, the two straight lines and the line connecting the midpoints are projected onto a plane. The two endpoints of the line connecting the midpoints are determined based on the projection lines. When the endpoints coincide, the coincident point is taken as point P. At the same time, the two straight lines form an angle line along point P.

7. The method for identifying the internal structure of a turbine blade according to claim 1, characterized in that, The method for obtaining the perpendicular line to the angle bisector of the horizontal projection line of the line connecting two midpoints is as follows: First, draw the angle bisector of the included angle line through point P. Finally, draw the perpendicular line from point P to the angle bisector.

8. The method for identifying the internal structure of a turbine blade according to claim 1, characterized in that, The method for identifying the internal structure of a turbine blade by rotating it so that the vertical line is parallel to the direction of the ray beam and acquiring a DR image of the turbine blade in this state is as follows: The rotation angle of the turbine blade is controlled so that the vertical line rotates until it is parallel to the rays emitted by the industrial CT scanner. Then, a DR image of the turbine blade is re-captured, and the internal structure and damage structure of the turbine blade are identified based on the DR image.

9. The method for identifying the internal structure of a turbine blade according to claim 1, characterized in that, The industrial CT emits X-rays or gamma rays.

10. A system for identifying the internal structure of a turbine blade, characterized in that, include: The acquisition modulus is used to obtain DR images of the turbine blade in its initial state; In the initial state, the tangent formed by the leading and trailing edges of the concave side of the turbine blade is perpendicular to the direction of the ray beam exit. The scanning module is used to obtain cross-sectional images of two locations along the height direction of the blade based on the DR image; The channel module is used to identify cooling channels based on tomographic cross-sectional images and to construct a midpoint connection line based on the midpoint of the cooling channels at the same location in two tomographic cross-sectional images. The first auxiliary line module is used to rotate the turbine blade until the two endpoints of the midpoint connecting line coincide in the horizontal projection direction to form point P. The second auxiliary line module is used to draw the perpendicular line to the angle bisector of the horizontal projection line of the line connecting the two midpoints, and this perpendicular line passes through point P. The identification module is used to rotate the turbine blade so that the vertical line is parallel to the direction of the ray beam, acquire a DR image of the turbine blade in this state, and then identify the internal structure of the turbine blade.

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