A Magnetostrictive Guided-Wave Nondestructive Testing Method With Multifrequency Excitation Pulse Signal

Huang

IEEE Trans. Instrum. Meas.

et al. 2020

The pipeline in-service needs to be inspected in certain period to master its structural health status. Ultrasonic guided wave which can propagate along pipelines with less energy loss provides an efficient method for long-term in situ inspection. Guided wave can detect both corrosion and cracks existing in structures. To overcome the problem of huge amounts of data and to maintain defect identification accuracy, the compressed sensing method for guided wave inspection is proposed. The compression process is essentially a scheme of analog to information conversion to compress the signal. It is accomplished by random demodulation and the equivalent sampling rate below the Nyquist rate helps to save most of storage. The compressed data is recovered to the sparse spatial domain based on the constructed dictionary from a guided wave propagation model. To verify the effectiveness of proposed method, both numerical simulations and experimental investigations are conducted. The results indicate the availability of compression and high accuracy of defect location after recovery. The influences of different compression schemes and compression ratios are further analyzed. In addition, the comparisons with direct recovery without compression and traditional analysis methods demonstrate the advantageous performance of the proposed method.

Section: B Construction Of Dictionary For Sparse Domainmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Compressed Sensing Method for Health Monitoring of Pipelines Based on Guided Wave Inspection

Huang

IEEE Trans. Instrum. Meas.

et al. 2020

IEEE Trans. Instrum. Meas.

“…For example, eddy currents have shown to be a very valuable tool to check the integrity of ferrous pipes [3]. Quality inspection of ferromagnetic pipes can also been performed by means of guided-wave methods [4]. Moreover, if the inner volume of the pipe is accessible, then a large number of endoscopic approaches based on different kind of sensors is also available [5], [6], [7], [8].…”

Section: Introductionmentioning

confidence: 99%

Nondestructive Evaluation of Microwave-Penetrable Pipes by Synthetic Aperture Imaging Enhanced by Full-Wave Field Propagation Model

Laviada

Ghasr

et al. 2019

A qualitative approach for microwave imaging multi-layered cylindrical structures (e.g., dielectric pipes) is proposed in this paper. This approach relies on a modified circular synthetic aperture imaging technique that exploits closed-form Green's function to account for the different propagation delays, internal reflections and refractions. The image can then be computed by employing a matched-filter expressed in terms of efficient Fourier Transforms. Consequently, a high-resolution and contactless approach for the inspection of this kind of structures is achieved. Moreover, the computational resources to render the images are negligible. Practical aspects of the technique such as sampling criteria, resolution and limitations of the technique are discussed. The efficacy of the method is illustrated via several examples including imaging of objects and anomalies inside different types of dielectric pipes.

“…In non-ferromagnetic materials such as aluminum, only the Lorentz force mechanism exists. As for the ferromagnetic materials, these two mechanisms exist simultaneously while the magnetostriction has been proved to be dominant [20]. Since the direction of the applied magnetic field coincides with the current direction of the coils, and they are both parallel to the plate surface.…”

Section: Introductionmentioning

confidence: 99%

Point-Focusing of Shear-Horizontal Wave Using Fan-Shaped Periodic Permanent Magnet Focusing Coils EMAT for Plate Inspection

et al. 2019