Gas turbine turbine wheel disc blade root groove array vortex coil arrangement and excitation method and device

Abstract

The application discloses a turbine wheel disc blade root groove array eddy current coil arrangement and excitation method and device, through optimization of key parameters such as inner diameter, outer diameter, number of turns, height and frequency of the array eddy current coil, the sensitivity, resolution and accuracy of detection are improved; through setting the array eddy current coil arrangement and quantity in a set manner, the fluctuation of detection sensitivity is reduced, the detection rate of different orientation defects is improved, and the risk of missed detection and false detection is reduced; through optimization of the excitation and receiving mode, the mutual interference between different coils is further reduced, and the detection sensitivity is improved. The application provides an efficient and accurate detection technical scheme for turbine wheel disc blade root groove defect detection through reasonable design of coil arrangement and excitation mode.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of nondestructive testing of gas turbine components, and particularly relates to a turbine wheel disc blade root groove array eddy current coil arrangement and excitation method and device. BACKGROUND

[0002] A gas turbine is a continuous-flow rotary machine (single machine) that converts thermal energy into mechanical work, including a compressor, a device that heats the working medium (such as a combustion chamber), a turbine, a control system, and auxiliary equipment. Its working principle is as follows: the compressor sucks in air, increases the pressure, and sends it into the combustion chamber, the fuel pump sprays fuel into the combustion chamber through the nozzle, mixes with the air and burns, the generated high-temperature and high-pressure gas enters the turbine to expand and do work, and finally the exhaust gas is discharged into the atmosphere and heat is released. Among them, part of the expansion work is transmitted to the compressor and other auxiliary machinery through the transmission shaft, and the remaining expansion work is output externally for power generation or as power.

[0003] The turbine wheel disc is one of the core components of the gas turbine, and the blade root grooves machined in the peripheral circumferential direction are the key parts of the turbine wheel disc and turbine blade assembly. The turbine wheel disc blade root groove needs to withstand complex cyclic stress during service, and is prone to defects such as cracks. Therefore, implementing detailed and effective nondestructive testing on the turbine wheel disc blade root groove is an important measure to ensure the safe and stable operation of the gas turbine.

[0004] Array eddy current testing technology is very suitable for high-sensitivity and high-precision nondestructive testing of turbine wheel disc blade root grooves due to its large-area scanning, high sensitivity, and direct coupling with complex-shaped parts. By optimizing the array eddy current coil arrangement and excitation method, the detection efficiency and accuracy can be further improved, providing strong support for the maintenance of gas turbines.

[0005] In the array eddy current testing of turbine wheel disc blade root grooves, coil arrangement is one of the key factors. The array eddy current probe is usually composed of multiple independent coils arranged in a specific manner. By adjusting the arrangement and number of coils, efficient detection of linear defects in different directions can be achieved. Excitation method is another key link. By designing appropriate excitation methods, the sensitivity and reliability of array eddy current testing can be further improved.

[0006] In summary, array eddy current testing technology has broad application prospects in the nondestructive testing of turbine wheel disc blade root grooves of gas turbines. By reasonably designing the coil arrangement and excitation method, efficient and accurate detection of blade root groove defects can be achieved, providing important protection for the safe and stable operation of gas turbines. SUMMARY

[0007] The turbine disk blade root slot array eddy current coil arrangement and excitation method and device of the application are designed to realize efficient and accurate detection of blade root slot defects by reasonably designing the coil arrangement and excitation mode.

[0008] In order to achieve the above-mentioned purpose, the application adopts the following technical solutions:

[0009] The application provides a turbine disk blade root slot array eddy current coil arrangement and excitation method, which comprises the following steps:

[0010] 1) Based on the structural size and electromagnetic characteristics of the detected turbine disk blade root slot, the inner diameter, outer diameter, number of turns, height and frequency of the array eddy current coil are determined;

[0011] 2) Based on the characteristic parameters of the coil, in combination with the orientation, size of the defect to be detected, and the consistency requirement of the detection sensitivity, the length of the array eddy current coil group, the coil center distance, the arrangement and the number of coils are determined;

[0012] 3) Based on the array eddy current coil arrangement, the sensitivity of defects of different orientations and sizes to the excitation mode is obtained by using a combination of simulation and test, and the excitation and receiving mode of the turbine disk blade root slot array eddy current coil of the gas turbine is determined.

[0013] Further improvement of the application is that in step 1), the inner diameter and outer diameter of the coil are determined according to the structural size and surface curvature of the detected turbine disk blade root slot, so as to ensure that the coil can closely fit the detected part;

[0014] The outer diameter of the coil is as large as possible under the condition of closely fitting the detected part, so as to induce a stronger and deeper eddy current field in the detected turbine disk blade root slot;

[0015] The inner diameter of the coil is as small as possible to make the induced magnetic field distribution more concentrated;

[0016] The number of turns of the coil is selected according to the electrical conductivity, thickness and surface roughness of the detected turbine disk blade root slot; under the condition of meeting the stability of the eddy current detection signal and the structural size limitation of the eddy current probe, a large number of turns are selected;

[0017] The height of the coil is as small as possible under the same number of turns to induce a more concentrated and stronger eddy current field at the detected part;

[0018] The frequency of the coil considers the penetration depth and intensity of the eddy current field, and is selected according to the detection depth and detection sensitivity requirement of the detected part to obtain the optimal detection frequency f opt The frequency of the coil is determined by the following formula:

[0019]

[0020] wherein, ρ is the resistivity of the detected part, t is the detection depth.

[0021] The further improvement of the present application is that in step 2), the length of the array eddy current coil group is determined according to the area to be covered by single scanning of the turbine disc blade root groove, and the whole turbine disc blade root groove detection surface should be covered by at most two axial scans, so the length of the coil group is not less than half of the cross-sectional profile length of the turbine disc blade root groove detection surface.

[0022] The array eddy current coil center distance selection step comprises:

[0023] Firstly, the minimum allowable center distance of the array eddy current coil is determined to ensure that the excitation magnetic fields of each excitation coil and the induced magnetic fields of the detection coil do not interfere with each other.

[0024] Secondly, the center distance is appropriately increased on the basis of the minimum center distance to obtain a relatively high detection sensitivity center distance.

[0025] Finally, the coil center distance is comprehensively determined in combination with the curvature of the detected part of the turbine disc blade root groove under the condition of ensuring the adhesion of the array eddy current coil group to the detected part.

[0026] The array eddy current coil arrangement mode adopts a two-row staggered arrangement mode, and the adjacent coils in the two rows are staggered by a set angle.

[0027] The number of array eddy current coils N is determined by the following formula:

[0028]

[0029] wherein, L is the cross-sectional profile length of the turbine disc blade root groove detection surface covered by single scanning, a is the center distance between the array eddy current coils in a single row.

[0030] The further improvement of the present application is that the inner diameter of the array eddy current coil is 0.3mm-0.8mm, the outer diameter is 1mm-2mm, and the number of turns is 5-10 turns.

[0031] The further improvement of the present application is that the frequency of the array eddy current coil is 500kHz-1200kHz.

[0032] The further improvement of the present application is that the center distance of the array eddy current coil is 2.5mm-4mm, and the number of array eddy current coil groups is generally not more than 120.

[0033] The further improvement of the present application is that the two rows of coils of the array eddy current coil group are staggered by 30°, and the center distance of the adjacent coils in the row is equal to the center distance of the two adjacent coils of the row and the adjacent row.

[0034] The further improvement of the present application is that in step 3), the excitation and reception of the array eddy current coil are realized through multiplexing technology.

[0035] The excitation and reception of the array eddy current coil are realized through multiplexing technology.

[0036] The further improvement of the present application is that the short-distance transmission-reception mode adopts two coils in the same row as the transmission coils, and two adjacent coils in the same row and three adjacent coils in the adjacent row as the reception coils.

[0037] The present application also provides a turbine disk blade root slot array eddy current coil arrangement and excitation device, which comprises:

[0038] The first confirmation module determines the inner diameter, outer diameter, number of turns, height and frequency of the array eddy current coil based on the structural size and electromagnetic characteristics of the detected turbine disk blade root slot.

[0039] The second confirmation module determines the length, coil center distance, arrangement and number of coils of the array eddy current coil group based on the characteristic parameters of the coil, the orientation and size of the defect to be detected, and the sensitivity consistency requirement of the detection.

[0040] The third confirmation module determines the excitation and reception mode of the turbine disk blade root slot array eddy current coil by combining simulation and test methods to obtain the sensitivity of defects of different orientations and sizes to the excitation mode.

[0041] Compared with the prior art, the present application has at least the following beneficial technical effects:

[0042] The gas turbine turbine disc blade root groove array eddy current coil arrangement and excitation method and device provided by the application improve the detection sensitivity, resolution and accuracy by optimizing the key parameters of the array eddy current coil, such as the inner diameter, outer diameter, number of turns, height and frequency; the detection sensitivity fluctuation is reduced, the detection rate of different orientation defects is improved, and the risk of missed detection and false detection is reduced by setting the array eddy current coil arrangement and quantity in a set manner; the mutual interference between different coils is further reduced, and the detection sensitivity is improved by optimizing the excitation and receiving modes. Finally, the array eddy current detection of the gas turbine turbine disc blade root groove with high sensitivity, high resolution and high reliability is realized, and the risk of defect missed detection and false detection is greatly reduced. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 It is a schematic diagram of the gas turbine turbine disc blade root groove array eddy current coil arrangement and excitation method of the application.

[0044] Figure 2 It is a schematic diagram of the coil in the gas turbine turbine disc blade root groove array eddy current coil arrangement and excitation method of the application.

[0045] Figure 3 It is a flowchart of the gas turbine turbine disc blade root groove array eddy current coil arrangement and excitation method of the application.

[0046] Figure 4 It is a structure block diagram of the gas turbine turbine disc blade root groove array eddy current coil arrangement and excitation device of the application.

[0047] BRIEF DESCRIPTION OF DRAWINGS:

[0048] 1-coil, 11-inner diameter, 12-outer diameter, 13-number of turns, 14-height, 21-array eddy current coil group length, 22-coil center distance, 23-array eddy current coil arrangement, T-transmit coil, R-receive coil. DETAILED DESCRIPTION

[0049] In the following, only certain exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the application. Therefore, the drawings and the description are considered to be exemplary in nature rather than limiting.

[0050] It should be understood that when used in the specification and the appended claims, the terms "comprise" and "include" indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0051] It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in this specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise.

[0052] It is further to be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items, and that the term "at least one of' encompasses any and all possible combinations of one or more of the associated listed items.

[0053] Various structural diagrams according to the disclosed embodiments of the present application are shown in the accompanying drawings. These diagrams are not drawn to scale in that certain details are exaggerated for the purpose of clarity and that certain other details are omitted. The shapes and relative sizes of the various regions, layers, and the relative positions of the regions / layers shown in the drawings are shown for illustrative purposes only and can deviate in actual devices due to manufacturing tolerances or technical limitations, and regions / layers with different shapes, sizes, relative positions can be additionally designed by those skilled in the art according to actual needs.

[0054] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0055] Embodiment 1

[0056] As shown in the drawings, the present application provides a gas turbine turbine disc blade root groove array eddy current coil arrangement and excitation method, comprising: Figures 1 to 3

[0057] S1, based on the structural size and electromagnetic characteristics of the detected turbine disc blade root groove, the inner diameter 11, the outer diameter 12, the number of turns 13, the height 14 and the frequency of the array eddy current coil 1 are determined;

[0058] S2, based on the characteristic parameters of the coil 1, combined with the orientation, size of the defect to be detected, and the sensitivity consistency requirement of detection, the array eddy current coil group length 21, the coil center distance 22, the arrangement 23 and the number of coils are determined;

[0059] S3, based on the arrangement of the array eddy current coil 1, the sensitivity of defects with different orientations and sizes to the excitation mode is obtained by combining simulation and test, and the excitation and receiving mode of the array eddy current coil 1 of the gas turbine turbine disc blade root groove is determined.

[0060] In this embodiment, step S1 includes: the inner diameter 11 and the outer diameter 12 of the coil 1 need to be determined according to the structural size and surface curvature of the detected turbine disc blade root groove, so as to ensure that the coil 1 can closely fit the detected part and improve the sensitivity and accuracy of detection.

[0061] ​The outer diameter 12 of the coil 1 should be appropriately large to induce a stronger and deeper eddy current field in the turbine disk blade root groove being detected, while ensuring close contact with the detection site.

[0062] The inner diameter 11 of the coil 1 should be appropriately small to make the induced magnetic field distribution more concentrated, thereby improving the sensitivity and resolution of the detection.

[0063] The number of turns 13 of the coil 1 should be selected comprehensively according to the electrical conductivity, thickness, and surface roughness of the turbine disk blade root groove being detected. Under the condition of meeting the stability of the eddy current detection signal and the size limitation of the eddy current probe structure, a larger number of turns 13 should be selected to improve the sensitivity and resolution and more efficiently detect small defects.

[0064] The height 14 of the coil 1 should be as small as possible under the same number of turns 13 to induce a more concentrated and stronger eddy current field in the detection site, thereby improving the sensitivity and resolution of the eddy current detection.

[0065] The frequency of the coil 1 should consider both the penetration depth and strength of the eddy current field, and should be selected according to the detection depth and sensitivity requirements of the detection site.

[0066] Preferably, the optimal detection frequency f opt is generally determined by the following formula:

[0067]

[0068] wherein, ρ is the resistivity of the detection site, t is the detection depth.

[0069] In the present embodiment, step S2 includes that the array eddy current coil group length 21 should be determined according to the area to be covered by a single scan of the turbine disk blade root groove. Generally, the entire turbine disk blade root groove detection surface should be covered by at most two axial scans, and therefore the coil group length should be no less than half of the cross-sectional profile length of the turbine disk blade root groove detection surface.

[0070] The center distance 22 of the array eddy current coil 1 is selected by the following steps:

[0071] S21, determine the minimum center distance allowed for the array eddy current coil 1 to ensure that the excitation magnetic fields of each excitation coil and the induced magnetic fields of the detection coil do not interfere with each other, thereby avoiding the risk of missed detection and false detection caused by too small coil center distance 22.

[0072] S22, appropriately increase the coil center distance 22 based on the minimum center distance to obtain a coil center distance 22 with relatively high detection sensitivity.

[0073] S23, in combination with the curvature of the turbine disk blade root groove detected site, the array eddy current coil group is guaranteed to be attached to the detected site, and the coil center distance 22 is determined comprehensively.

[0074] The array eddy current coil arrangement 23 adopts a two-row staggered arrangement mode, and a set angle is staggered between the adjacent coils of the two rows, reduces the fluctuation of detection sensitivity, improves the detection rate of different orientation defects, and reduces the possibility of missed detection.

[0075] The number of array eddy current coils 1 N Determined by the following formula:

[0076]

[0077] Wherein, L The cross-sectional profile length of the turbine disk blade root groove detection surface covered by a single scan, a The center distance between the coils in a single row array eddy current coil.

[0078] In this embodiment, the step S3 includes: the excitation and reception of the array eddy current coil 1 are realized by multiplexing technology, avoiding mutual interference between different coils 1.

[0079] Specifically, the above functions are realized by a multiplexer, which can be integrated on the array eddy current probe or integrated on the array eddy current detector main machine, and the present application does not make specific limitation.

[0080] The excitation and reception mode of the array eddy current coil 1, combined with the electromagnetic characteristics of the detected turbine disk blade root groove, the short distance transmission-reception mode is more sensitive to near-surface micro defects, so the short distance transmission-reception mode is adopted. From one end of the array eddy current coil group, the coils are sequentially excited, and the adjacent coils receive the electromagnetic signals generated by the excited coils; at the next moment, the previous receiving coil acts as a transmitting coil, and the next adjacent coil receives the electromagnetic signals generated by the excited coil, and so on.

[0081] Specifically, the array eddy current coil 1 can be used as an excitation coil or a receiving coil. However, in the present transmission-reception mode, only a single array eddy current coil 1 can adopt one of the two modes at the same time.

[0082] Specifically, by sequentially exciting the array eddy current coil 1 from one end to the other end, the excitation and reception of the coils in the entire length direction of the array eddy current coil group are completed in a very short time, and through the matching with the axial scanning speed of the array eddy current probe, the full coverage of the array eddy current coil group in the length direction is realized.

[0083] Preferably, the inner diameter 11 of the array eddy current coil 1 is 0.3mm-0.8mm, the outer diameter 12 is 1mm-2mm, and the number of turns 13 is 5-10 turns.

[0084] Preferably, the frequency of the array eddy current coil 1 is 500kHz-1200kHz.

[0085] Preferably, the center distance 22 of the array eddy current coil is 2.5mm-4mm, and the number of array eddy current coil groups N Generally not more than 120.

[0086] Preferably, the two rows of coils of the array eddy current coil group are arranged with a stagger of 30°, and the center distance 22 of the adjacent coils in the row is equal to the center distance 22 of the adjacent coils in the row and the adjacent 2 coils in the adjacent row.

[0087] Preferably, the short-distance transmission-reception mode generally uses two coils in the same row as the transmitting coils, and two adjacent coils in the same row and three adjacent coils in the adjacent row as the receiving coils.

[0088] Example 2

[0089] As shown in Figure 4 The gas turbine turbine disc blade root groove array eddy current coil arrangement and excitation device provided by the application comprises:

[0090] A first confirmation module determines the inner diameter, outer diameter, number of turns, height and frequency of the array eddy current coil based on the structural size and electromagnetic characteristics of the detected turbine disc blade root groove;

[0091] A second confirmation module determines the array eddy current coil group length, coil center distance, arrangement and coil number based on the characteristic parameters of the coil, in combination with the orientation, size of the defect to be detected, and the sensitivity consistency requirement of the detection;

[0092] A third confirmation module determines the excitation and reception mode of the gas turbine turbine disc blade root groove array eddy current coil based on the array eddy current coil arrangement, and uses a combination of simulation and test to obtain the sensitivity of defects of different orientations and sizes to the excitation mode.

[0093] Example 3

[0094] Step S1: Determine the parameters of the array eddy current coil

[0095] Taking the structural size and surface curvature of the 9FA type gas turbine turbine disc blade root groove to be detected as an example, in order to meet the detection requirements of the blade root groove cracks at the minimum curvature radius, the inner diameter 11 of the array eddy current coil 1 is 0.4mm, the outer diameter 12 is 1mm, the number of turns 13 is 6 turns, the height 14 is 0.5mm, and the frequency is 1000kHz.

[0096] Step S2: Determine the arrangement of the array eddy current coil group

[0097] According to the length of the cross-section profile of the detection surface of the 9FA type gas turbine turbine disc blade root groove, the two rows of coils of the array eddy current coil group are arranged staggered by 30°, the length 21 of the array eddy current coil group is selected as 100 mm, the center distance 22 is 3 mm, and the number of coils is 70.

[0098] Step S3: determining the transmission-reception mode

[0099] Two coils in the same row are used as the transmitting coils, and two adjacent coils in the same row and three adjacent coils in the adjacent row are used as the receiving coils.

[0100] Meanwhile, the sensitivity, accuracy and reliability of the detection system are evaluated by testing on the 9FA type gas turbine turbine disc blade root groove.

[0101] The above shows and describes the basic principles and main features of the present application and the advantages of the present application, and it is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be realized in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting, the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application. Any reference signs in the claims should not be regarded as limiting the claims involved.

[0102] In addition, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be combined to form other embodiments which can be understood by those skilled in the art. The above is only to illustrate the technical idea of the present application, and cannot limit the protection scope of the present application, and any modification made on the basis of the technical solutions according to the technical idea of the present application falls within the protection scope of the claims of the present application.

Claims

1. A method for arranging and exciting eddy current coils in a gas turbine blade root slot array, characterized in that, include: 1) Based on the structural dimensions and electromagnetic characteristics of the turbine disk blade root groove under test, determine the inner diameter, outer diameter, number of turns, height, and frequency of the array eddy current coil; the inner and outer diameters of the array eddy current coil are determined according to the structural dimensions and surface curvature of the turbine disk blade root groove under test to ensure that the array eddy current coil can fit tightly against the part under test. The outer diameter of the arrayed eddy current coils should be as large as possible while ensuring close contact with the part being tested, so as to induce a stronger and deeper eddy current field in the root groove of the turbine disk blade being tested. The inner diameter of the arrayed eddy current coils should be as small as possible; The number of turns of the array eddy current coil is selected based on a comprehensive consideration of the conductivity, thickness, and surface roughness of the root groove of the turbine disk blade being tested; a larger number of turns is selected while meeting the requirements of eddy current detection signal stability and eddy current probe structural size limitations. The height of the arrayed eddy current coils should be as small as possible for the same number of turns, so as to induce a more concentrated and stronger eddy current field at the detected part; The frequency of the array eddy current coils takes into account both the penetration depth and intensity of the eddy current field, and is selected based on the detection depth and sensitivity requirements of the detected part to achieve the optimal detection frequency. f opt Determined by the following formula: in, ρ The resistivity of the measured area. t For detection depth; 2) Based on the characteristic parameters of the array eddy current coils, combined with the orientation and size of the defects to be detected, as well as the sensitivity consistency requirements of the detection, determine the length, center distance, arrangement and number of the array eddy current coils; the length of the array eddy current coils is determined according to the area to be covered by a single scan of the turbine blade root groove. It is required that the entire turbine blade root groove detection surface should be covered by a maximum of two axial scans. Therefore, the length of the array eddy current coils is not less than half the cross-sectional profile length of the turbine blade root groove detection surface. The steps for selecting the center distance of the array eddy current coils include: First, determine the minimum allowable center distance of the arrayed eddy current coils; Secondly, by appropriately increasing the center distance based on the minimum center distance, a center distance with relatively high detection sensitivity can be obtained. Finally, taking into account the surface curvature of the turbine blade root groove being tested, the center distance is determined comprehensively while ensuring the fit between the array eddy current coil and the tested part. The array eddy current coils are arranged in a two-row staggered pattern, with the two rows of adjacent coils offset by a set angle. Number of arrayed eddy current coils N Determined by the following formula: in, L The length of the cross-sectional profile of the turbine disk blade root groove inspection surface covered by a single scan. a The center distance between a single row of arrayed eddy current coils; 3) Based on the array eddy current coil arrangement, a combination of simulation and experimentation was used to obtain the sensitivity of defects with different orientations and sizes to the excitation mode, and to determine the excitation and reception modes of the array eddy current coils of the turbine blade root slot of the gas turbine.

2. The method for arranging and exciting eddy current coils in the root slot array of a gas turbine disk blade according to claim 1, characterized in that, The array eddy current coil has an inner diameter of 0.3mm to 0.8mm, an outer diameter of 1mm to 2mm, and 5 to 10 turns.

3. The method for arranging and exciting eddy current coils in the root slot array of a gas turbine disk blade according to claim 1, characterized in that, The frequency of the arrayed eddy current coils is 500kHz to 1200kHz.

4. The method for arranging and exciting eddy current coils in the root slot array of a gas turbine disk blade according to claim 1, characterized in that, The center distance of the arrayed eddy current coils is 2.5mm to 4mm, and the number of arrayed eddy current coils is generally no more than 120.

5. The method for arranging and exciting eddy current coils in the root slot array of a gas turbine disk blade according to claim 1, characterized in that, The array of eddy current coils consists of two rows of adjacent coils staggered by 30°. The center distance between adjacent coils in this row is equal to the center distance between the coils in this row and the two adjacent coils in the next row.

6. The method for arranging and exciting eddy current coils in the root slot array of a gas turbine disk blade according to claim 1, characterized in that, In step 3), the excitation and reception of the arrayed eddy current coils are achieved through multiplexing technology; The excitation and reception method of the array eddy current coils, combined with the electromagnetic characteristics of the turbine disk blade root slot under test, adopts a short-distance transmit-receive method; starting from one end of the array eddy current coils, the coils are excited sequentially, and the adjacent coils receive the electromagnetic signals generated by the excitation coils at the same time; at the next moment, the previous receiving coil becomes the transmitting coil, and its next adjacent coil receives the electromagnetic signals generated by the excitation coil, and so on.

7. The method for arranging and exciting eddy current coils in the root slot array of a gas turbine disk blade according to claim 6, characterized in that, The short-range transmit-receive method uses two coils in the same row as the transmitting coils, and two adjacent coils in the same row and three adjacent coils in adjacent rows as the receiving coils.

8. A gas turbine disk blade root slot array eddy current coil arrangement and excitation device, employing the gas turbine disk blade root slot array eddy current coil arrangement and excitation method as described in any one of claims 1 to 7, characterized in that, include: The first confirmation module determines the inner diameter, outer diameter, number of turns, height, and frequency of the arrayed eddy current coils based on the structural dimensions and electromagnetic characteristics of the root groove of the turbine disk blade under test. The second confirmation module, based on the characteristic parameters of the array eddy current coils, combined with the orientation and size of the defect to be detected, and the consistency requirements of the detection sensitivity, determines the length, center distance, arrangement and number of the array eddy current coils; The third verification module, based on the array eddy current coil arrangement, uses a combination of simulation and experimentation to obtain the sensitivity of defects of different orientations and sizes to the excitation mode, and determines the excitation and reception modes of the array eddy current coils in the root slots of the gas turbine disk blades.

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