A glass fiber pipe defect detection method and system based on asymmetric torsional ultrasonic guided wave mode

Abstract

The application provides a glass fiber pipe defect detection method and system based on an asymmetric torsional ultrasonic guided wave mode, and the axial distance range of an excitation and a receiving piezoelectric ceramic array is controlled within half of a period ZT of an energy focusing coefficient change of a theoretically calculated asymmetric torsional guided wave T(M, 1) mode. An asymmetric torsional guided wave close to an ideal half-coverage sensor is excited by using a piezoelectric ceramic array with a circumferential coverage rate of greater than or equal to 50%. The energy focusing coefficient of the asymmetric torsional guided wave signal is calculated to evaluate the axial position of the defect. The application can detect the defects of the buried glass fiber pipe under the premise of partial excavation. Not only the glass fiber pipe is prevented from being damaged due to misoperation in the excavation process, but also only half of the circumference of the glass fiber pipe needs to be exposed by excavation at both ends of the glass fiber pipe to be detected, thereby reducing the workload of the workers in excavation. Meanwhile, the problem that the defects at some circumferential positions of the glass fiber pipe are not easy to be observed and found is solved.

Description

Technical Field

[0001] This invention relates to the field of glass fiber tube defect detection technology, and in particular to a glass fiber tube defect detection method and system based on asymmetric torsional ultrasonic guided wave mode. Background Technology

[0002] Fiberglass tubes, due to their lightweight, high strength, and corrosion resistance, are widely used in modern industry. From deep-sea oil platforms to underground coal mines, from urban water supply networks to corrosive media transport lines in chemical plants, fiberglass tubes are replacing traditional materials in numerous fields. However, due to the heterogeneity and anisotropy of fiberglass materials and the complexity of manufacturing processes, various types of defects are easily generated during their lifecycle, including manufacturing, storage, transportation, installation, and service. Conventional techniques struggle to achieve non-destructive testing of defects in fiberglass tubes over short periods and long distances. Ultrasonic guided wave testing technology, with its advantages of speed and long-distance operation, holds promise for damage assessment in fiberglass tubes. However, traditional self-excited and self-received signal acquisition modes have weak energy in the highly attenuated structure of fiberglass tubes, making it difficult to obtain defect reflection echo signals for defect detection. While single-excited and single-received modes can effectively receive direct waves, they are difficult to determine the presence of defects and their axial and circumferential positions under parametric conditions. The non-uniform energy distribution of asymmetric torsional guided wave modes is helpful for defect detection and the determination of axial and circumferential positions in fiberglass tubes. In summary, there is still no non-destructive testing method that can simultaneously and effectively determine whether there are defects in glass fiber tubes, as well as locate the axial and circumferential positions of the defects. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide a method and system for detecting defects in buried fiberglass tubes based on asymmetric torsional ultrasonic guided wave modes, which can detect defects in buried fiberglass tubes under partial excavation conditions. This not only avoids damage to the fiberglass tubes caused by misoperation during excavation, but also reduces the workload for workers by requiring only excavation at both ends of the fiberglass tube to expose half of its circumference. Simultaneously, it solves the problem that defects at certain circumferential locations of fiberglass tubes are difficult to observe and detect.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes, comprising the following steps:

[0005] Step 1: First, the circumferential distribution law of energy of the low-order asymmetric torsional guided wave T(M,1) mode at a specific frequency propagating in a glass fiber tube is derived by using normal mode decomposition theory.

[0006] Step 2: Utilizing in-plane polarized in-plane shear-type piezoelectric ceramics d 24The array excites a low-order asymmetric torsional waveguide mode T(M,1) in a glass fiber tube;

[0007] Step 3: Set the circumferential coverage of the glass fiber tube for the discrete piezoelectric ceramic array to ≥50%;

[0008] Step 4: Utilize the length period Z of the energy focusing degree of the low-order asymmetric torsional waveguide mode T(M,1) in the glass fiber tube as a function of axial distance. T Determine the spacing between the excitation and receiving sensors;

[0009] Step 5: Characterize the defects in the glass fiber tube by using the energy focusing coefficient of the asymmetric torsional guided wave;

[0010] Step 6: Using 2π / θ as the step, sequentially excite some sensors in the piezoelectric array. By analyzing the distribution of the asymmetric torsional guided wave mode angle profile and the change law of the energy focusing coefficient before and after the defect, the presence of defects and the axial and circumferential positions of the defects are evaluated by the quantitative relationship between the symmetry center of the asymmetric torsional guided wave mode angle profile and the negative minimum point of the energy focusing coefficient curve.

[0011] In a preferred embodiment, the normal mode decomposition theory consists of a symmetric mode T(0,1) and multiple torsional bending modes F(M,1) with the same modulus but different circumferential orders, where M≠0; the asymmetric torsional ultrasonic guided wave mode generated under local load is obtained by superimposing these mutually orthogonal modes according to a set coefficient; the velocity field of the asymmetric torsional ultrasonic guided wave mode is expressed as: ; where ω and θ and z represent the angular frequency and wavenumber of the excited asymmetric torsional guided wave, respectively; r, θ and z represent the radial, circumferential and axial directions in the glass fiber tube, respectively. It is the velocity field resulting from the superposition of all ultrasonic guided wave modes; and The amplitude and velocity fields of an ultrasonic guided wave mode with modulus M and circumferential order N are respectively. The axial traveling wave factor is used to describe the propagation characteristics of the guided wave along the axial direction z. The time harmonicity factor describes the simple harmonic vibration characteristics of the guided wave.

[0012] In a preferred embodiment: in-plane polarized thickness shear piezoelectric ceramic d 24 The piezoelectric ceramics in the array are equidistantly half-covered around the circumference of the glass fiber tube, covering approximately half of the circumference; the length direction is polarized, and an electric field is applied in the width direction.

[0013] In a preferred embodiment: in-plane polarized thickness shear piezoelectric ceramic d 24In the array, the optimal number of sensors is determined based on a model of a low-order asymmetric torsional waveguide T(M,1) mode excited by a semi-covered loading in a glass fiber tube.

[0014] In a preferred embodiment: the length period of the energy focusing degree of the low-order asymmetric torsional waveguide mode in the glass fiber tube in step 4 as a function of axial distance is: The above formula gives the length period of the energy variation with axial propagation distance of a certain asymmetric torsional guided wave mode in a glass fiber tube of a specific material and size; where R o , R i Z represents the inner and outer radii of the glass fiber tube, ω is the frequency of the asymmetric torsional guided wave, E is the elastic modulus of the glass fiber, μ is the Poisson's ratio of the glass fiber, and ρ is the density of the glass fiber. When detecting defects, a single-excitation, single-receiver signal acquisition mode is used, and the axial distance between the excitation and receiving sensors is equal to Z. T / 4.

[0015] In a preferred embodiment: the formula for the energy focusing degree coefficient I in step 5 is as follows: ; Calculate the energy ratio within the two circumferential ranges of the glass fiber tube as the energy focusing coefficient for the asymmetric torsional guided wave; A i,θ A j,θ+π These are the signal amplitudes at the n / 2th circumferential positions within the angular ranges of (270°, 0°) ∪ (0°, 90°) and (90°, 180°) ∪ (180°, 270°), respectively; min(A) represents the signal amplitude with the smallest amplitude among all circumferential positions.

[0016] In a preferred embodiment: In step 6, during the excitation process of the stepping rotating piezoelectric ceramic array, the quantitative relationship between the asymmetric torsional guided wave mode focusing degree and the axial and circumferential positions of the defect is established; then, the quantitative relationship between the symmetry center of the asymmetric torsional guided wave mode angular profile distribution and the negative minimum point of the energy focusing coefficient curve is used to evaluate whether there is a defect and the axial and circumferential positions of the defect.

[0017] The present invention also provides a glass fiber tube defect detection system based on asymmetric torsional ultrasonic guided wave mode, including a processor, a memory and a bus. The memory stores machine-readable instructions executed by the processor. When the system is running, the processor and the memory communicate through the bus, and the machine-readable instructions are executed by the processor as described in the glass fiber tube defect detection method based on asymmetric torsional ultrasonic guided wave mode.

[0018] The present invention also provides a computer device, comprising:

[0019] The processor, memory, and bus, wherein the memory stores machine-readable instructions executed by the processor;

[0020] When the computer device is running, the processor and the memory communicate via a bus, and when the machine-readable instructions are executed by the processor, a glass fiber tube defect detection method based on asymmetric torsional ultrasonic guided wave mode is performed as described above.

[0021] The present invention also provides a computer-readable storage medium, comprising:

[0022] The computer-readable storage medium contains a computer program;

[0023] The computer program is executed by the processor to perform a method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes, as described above.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The semi-circular discrete coverage piezoelectric ceramic array proposed in this invention breaks through the limitation of traditional magnetostrictive sensors with full semi-circular coverage and can generate asymmetric torsional guided waves in high-attenuation glass fiber tubes.

[0026] 2. This invention optimizes the number of sensors in a circumferentially discrete piezoelectric ceramic array (circumferential coverage ≥ 50%), enabling the excitation of high-energy asymmetric torsional guided waves in a glass fiber tube while minimizing manpower and time.

[0027] 3. This invention introduces a 45° step rotation excitation strategy for a semi-circular discrete coverage piezoelectric ceramic array. Through multi-angle excitation and reception, it can determine whether there are defects in the glass fiber tube. Compared with existing non-destructive testing methods, this method is more robust and less affected by noise.

[0028] 4. The method described above in this invention can locate the circumferential position of the defect using the energy focusing coefficient of the asymmetric torsional guided wave at each circumferential position. The experimental results are easy to observe and are not easily affected by noise. Attached Figure Description

[0029] Figure 1 This invention presents the theoretical and simulation results of the circumferential energy distribution quantification relationship for asymmetric torsional guided wave excitation using an n-chip discrete in-plane polarization in-plane shear-type piezoelectric ceramic d24 sensor array to replace the traditional magnetostrictive patch sensor.

[0030] Figure 2This is a quantitative comparison chart of the standard deviation of the asymmetric torsional waveguide excited by an ideal semi-covered magnetostrictive sensor for a glass fiber tube with an outer diameter of 40 mm and a wall thickness, using an n-piece discrete in-plane polarized in-plane shear type piezoelectric ceramic d24 array.

[0031] Figure 3 This is a schematic diagram of a method for detecting defects in glass fiber tubes by stepping rotation to excite an in-plane shear-type piezoelectric ceramic d24 array within a semi-circular discrete covering surface in an embodiment of the present invention.

[0032] Figure 4 The diagram shows the theoretical curve of the angular profile obtained by the normal mode decomposition method before the asymmetric torsional guided wave passes through the defect, as used in this embodiment of the invention, and the distribution of angular profile points obtained by experiment.

[0033] Figure 5 This is a distribution diagram of the angular contour points obtained by normal mode decomposition method after the asymmetric torsional guided wave passes through the defect using step rotation excitation in an embodiment of the present invention.

[0034] Figure 6 This is a graph showing the energy focusing coefficient of an asymmetric torsional waveguide excited by stepping rotation in a defect-free glass fiber tube, as described in an embodiment of the present invention.

[0035] Figure 7 This is a graph showing the energy focusing coefficient of an asymmetric torsional waveguide excited by stepping rotation in a defective glass fiber tube, as described in an embodiment of the present invention. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0037] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0038] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application; as used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise; furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0039] A method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes, referenced Figure 1-7 This falls under the field of non-destructive testing. It includes the following steps:

[0040] Step 1: First, the circumferential distribution law of energy of the low-order asymmetric torsional guided wave T(M,1) mode at a specific frequency propagating in a glass fiber tube is derived by using normal mode decomposition theory.

[0041] Step 2: Utilizing in-plane polarized in-plane shear-type piezoelectric ceramics d 24 The array excites a low-order asymmetric torsional waveguide mode T(M,1) in a glass fiber tube;

[0042] Step 3: The circumferential coverage of the glass fiber tube in the discrete piezoelectric ceramic array is ≥50%;

[0043] Step 4: Utilize the length period Z of the energy focusing degree of the low-order asymmetric torsional guided wave mode in the glass fiber tube as a function of axial distance. T Determine the spacing between the excitation and receiving sensors;

[0044] Step 5: Characterize the defects in the glass fiber tube by using the energy focusing coefficient of the asymmetric torsional guided wave;

[0045] Step 6: Using 2π / θ as the step, sequentially excite some sensors in the piezoelectric array. By analyzing the distribution of the asymmetric torsional guided wave mode angle profile and the change law of the energy focusing coefficient before and after the defect, the presence of defects and the axial and circumferential positions of the defects are evaluated by the quantitative relationship between the symmetry center of the asymmetric torsional guided wave mode angle profile and the negative minimum point of the energy focusing coefficient curve.

[0046] In step 1, the normal mode decomposition theory consists of a symmetric mode T(0,1) and multiple bending modes T(M,1) with the same modulus but different circumferential orders. The asymmetric torsional guided wave generated under local load is obtained by superimposing these mutually orthogonal modes with certain coefficients. Its velocity field can be expressed as: Where ω and θ and z represent the angular frequency and wavenumber of the excited asymmetric torsional guided wave, respectively. r, θ, and z represent the radial, circumferential, and axial directions in the glass fiber tube, respectively. The velocity field of an ultrasonic guided wave mode with modulus M and circumferential order N: .in, , , respectively, represent the radial and circumferential wave structures of the ultrasonic guided wave mode. The magnitude coefficients of mutually orthogonal states are expressed as follows: .in, This represents the energy flux density of the ultrasonic guided wave mode. and These represent the amplitude coefficients in the circumferential and axial directions, respectively.

[0047] In step 2: The piezoelectric ceramics in the array are equidistantly semi-covered around the circumference of the glass fiber tube, covering approximately half of the circumference. The piezoelectric ceramics are 15 mm long, 8 mm wide, and 3 mm thick. They are polarized along the length direction, and an electric field is applied along the width direction. The optimal number of sensors is determined based on a model of a low-order asymmetric torsional guided wave T(M,1) mode excited by loading the semi-covered area in the glass fiber tube.

[0048] In step 4, the length period of the energy focusing degree of the low-order asymmetric torsional guided wave mode in the glass fiber tube as a function of axial distance is: This formula gives the length period of the energy variation with axial propagation distance of a certain asymmetric torsional guided wave mode in a glass fiber tube of a specific material and size. Where R... o , R i Here, ω represents the inner and outer radii of the glass fiber tube, ν is the frequency of the asymmetric torsional guided wave, E is the elastic modulus of the glass fiber, ν is the Poisson's ratio of the glass fiber, and ρ is the density of the glass fiber. When detecting defects, a single-excitation, single-receiver signal acquisition mode is used, with the axial distance between the excitation and receiving sensors equal to Z. T / 4.

[0049] Wavelength of the asymmetric torsional guided wave mode L(N,M) The corresponding Lamb wave wavelength within the plate corresponding to the glass fiber tube can be determined. The formula for calculation is:

[0050]

[0051] Based on the relationship between wave number, frequency, and phase velocity, we can obtain:

[0052]

[0053] At the same time, due to The value is much less than 1, which further simplifies the above formula:

[0054]

[0055] Wavenumber at this time The expression is:

[0056]

[0057] Therefore, it can be achieved through the distance factor. The formula for the distance period of the energy distribution variation in asymmetric torsional guided waves is as follows: .

[0058] In step 5, the formula for the energy focusing degree coefficient is: The energy ratio within the two circumferential regions of the glass fiber tube is calculated as the energy focusing coefficient for the asymmetric torsional guided wave. A i,θ A j,θ+π These are the signal amplitudes at the n / 2th circumferential positions within the angular ranges of (270°, 0°) ∪ (0°, 90°) and (90°, 180°) ∪ (180°, 270°), respectively. min(A) represents the signal amplitude with the smallest amplitude among all circumferential positions.

[0059] In step 6, the excitation strategy for the 45° step-rotating piezoelectric array utilizes a defect-induced asymmetric torsional waveguide model. During the step-rotating array process, the quantified relationships between the asymmetric torsional waveguide normal modes, energy focusing degree, and the axial and circumferential positions of the defects are established. Then, the quantified relationship between the center of symmetry of the angular profile distribution of the normal mode decomposition and the negative minimum point of the energy focusing coefficient curve is used to assess the presence of defects and their axial and circumferential positions.

[0060] The technical processing flow of the proposed program code can be systematically described as follows:

[0061] First, based on the theoretical dispersion curve and core propagation parameters of asymmetric torsional guided waves in a cylindrical shell structure, a corresponding theoretical asymmetric torsional guided wave angular profile distribution model is constructed and plotted. This theoretical model serves as a benchmark for subsequent comparative analysis, clearly characterizing the ideal distribution shape and extreme point location of guided wave energy along the circumference of the pipe under defect-free ideal operating conditions.

[0062] Subsequently, the theoretical angular profile distribution was compared item by item with the angular profile distribution maps obtained from simulation calculations and experimental measurements. During the experimental data acquisition phase, the circumferential rotation of the excitation end was strictly completed according to a fixed step angle. At each step, a new reference position was reached, and signal acquisition and data recording were performed at the eight circumferentially positioned monitoring points, ultimately generating the measured angular profile distribution map under this operating condition. By comparing the morphological differences, extreme point offsets, and energy distribution concentration between the theoretical and measured curves, the consistency between the actual propagation environment and the theoretical model can be preliminarily assessed.

[0063] Simultaneously, based on the signal amplitude data collected from eight monitoring points, an energy focusing coefficient distribution map was calculated and plotted according to a preset formula. The calculated energy focusing coefficient map was then cross-validated with the theoretically ideal energy focusing coefficient map. If the two maps showed a high degree of agreement in terms of numerical magnitude, distribution trend, and focusing characteristics, it was determined that there were no obvious defects in the welded joint area; conversely, if there was a significant deviation, it indicated that the welded joint had defects that disrupted the waveguide symmetry. This method can achieve qualitative identification and quantitative evaluation of defects.

Claims

1. A method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes, characterized in that, Includes the following steps: Step 1: First, the circumferential distribution law of energy of the low-order asymmetric torsional guided wave T(M,1) mode at a specific frequency propagating in a glass fiber tube is derived by using normal mode decomposition theory. Step 2: Utilizing in-plane polarized in-plane shear-type piezoelectric ceramics d 24 The array excites a low-order asymmetric torsional waveguide mode T(M,1) in a glass fiber tube; Step 3: Set the circumferential coverage of the glass fiber tube for the discrete piezoelectric ceramic array to ≥50%; Step 4: Utilize the length period Z of the energy focusing degree of the low-order asymmetric torsional waveguide mode T(M,1) in the glass fiber tube as a function of axial distance. T Determine the spacing between the excitation and receiving sensors; Step 5: Characterize the defects in the glass fiber tube by using the energy focusing coefficient of the asymmetric torsional guided wave; Step 6: Using 2π / θ as the step, sequentially excite some sensors in the piezoelectric array. By analyzing the distribution of the asymmetric torsional guided wave mode angle profile and the change law of the energy focusing coefficient before and after the defect, the presence of defects and the axial and circumferential positions of the defects are evaluated by the quantitative relationship between the symmetry center of the asymmetric torsional guided wave mode angle profile and the negative minimum point of the energy focusing coefficient curve.

2. The method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes according to claim 1, characterized in that, The normal mode decomposition theory consists of a symmetric mode T(0,1) and multiple torsional bending modes F(M,1) with the same modulus but different circumferential orders, where M≠0; the asymmetric torsional ultrasonic guided wave mode generated under local load is obtained by superimposing these mutually orthogonal modes according to set coefficients; the velocity field of the asymmetric torsional ultrasonic guided wave mode is expressed as: ; where ω and θ and z represent the angular frequency and wavenumber of the excited asymmetric torsional guided wave, respectively; r, θ and z represent the radial, circumferential and axial directions in the glass fiber tube, respectively. It is the velocity field resulting from the superposition of all ultrasonic guided wave modes; and The amplitude and velocity fields of an ultrasonic guided wave mode with modulus M and circumferential order N are respectively. It represents the axial traveling wave factor, which describes the propagation characteristics of the guided wave along the axial direction z. The time harmonicity factor describes the simple harmonic vibration characteristics of the guided wave.

3. The method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes according to claim 1, characterized in that: In-plane polarized thickness shear type piezoelectric ceramics d 24 The piezoelectric ceramics in the array are equidistantly half-covered around the circumference of the glass fiber tube, covering approximately half of the circumference; the length direction is polarized, and an electric field is applied in the width direction.

4. The method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes according to claim 1, characterized in that: In-plane polarized thickness shear type piezoelectric ceramics d 24 In the array, the optimal number of sensors is determined based on a model of a low-order asymmetric torsional waveguide T(M,1) mode excited by a semi-covered loading in a glass fiber tube.

5. The method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes according to claim 1, characterized in that: In step 4, the length period of the energy focusing degree of the low-order asymmetric torsional guided wave mode in the glass fiber tube as a function of axial distance is: The above formula gives the length period of the energy variation with axial propagation distance of a certain asymmetric torsional guided wave mode in a glass fiber tube of a specific material and size; where R o , R i Z represents the inner and outer radii of the glass fiber tube, ω is the frequency of the asymmetric torsional guided wave, E is the elastic modulus of the glass fiber, μ is the Poisson's ratio of the glass fiber, and ρ is the density of the glass fiber. When detecting defects, a single-excitation, single-receiver signal acquisition mode is used, and the axial distance between the excitation and receiving sensors is equal to Z. T / 4.

6. The method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes according to claim 1, characterized in that: The formula for the energy focusing degree coefficient I in step 5 is: ; Calculate the energy ratio within the two circumferential ranges of the glass fiber tube as the energy focusing coefficient for the asymmetric torsional guided wave; A i,θ A j,θ+π These are the signal amplitudes at the n / 2th circumferential positions within the angular ranges of (270°, 0°) ∪ (0°, 90°) and (90°, 180°) ∪ (180°, 270°), respectively. min(A) represents the signal amplitude with the smallest amplitude among all signals at all circumferential positions.

7. The method for detecting defects in glass fiber tubes based on asymmetric torsional ultrasonic guided wave modes according to claim 1, characterized in that: In step 6, during the excitation process of the stepping rotating piezoelectric ceramic array, the quantitative relationship between the focusing degree of the asymmetric torsional guided wave mode and the axial and circumferential positions of the defect is established. Then, the quantitative relationship between the center of symmetry of the angular profile distribution of the asymmetric torsional guided wave mode and the negative minimum point of the energy focusing coefficient curve is used to evaluate whether there is a defect and the axial and circumferential positions of the defect.

8. A glass fiber tube defect detection system based on asymmetric torsional ultrasonic guided wave mode, comprising a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executed by the processor; characterized in that, When the system is running, the processor and the memory communicate via a bus, and the machine-readable instructions are executed by the processor as described in any one of claims 1 to 7. This is a glass fiber tube defect detection method based on asymmetric torsional ultrasonic guided wave mode.

9. A computer device, characterized in that, include: The processor, memory, and bus, wherein the memory stores machine-readable instructions executed by the processor; When the computer device is running, the processor communicates with the memory via a bus, and when the machine-readable instructions are executed by the processor, they perform a glass fiber tube defect detection method based on asymmetric torsional ultrasonic guided wave mode as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, include: The computer-readable storage medium contains a computer program; The computer program is executed by the processor to perform a glass fiber tube defect detection method based on asymmetric torsional ultrasonic guided wave mode as described in any one of claims 1 to 7.

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