Calculation of Guided Wave Dispersion Characteristics Using a Three-Transducer Measurement System

Abstract

Featured Application: Rapid generation of dispersion curves for guided wave applications when knowledge of the material properties and thickness of the structure to be inspected are unknown.Abstract: Guided ultrasonic waves are of significant interest in the health monitoring of thin structures, and dispersion curves are important tools in the deployment of any guided wave application. Most methods of determining dispersion curves require accurate knowledge of the material properties and thickness of the structure to be inspected, or extensive experimental tests. This paper presents an experimental technique that allows rapid generation of dispersion curves for guided wave applications when knowledge of the material properties and thickness of the structure to be inspected are unknown. The technique uses a single source and measurements at two points, making it experimentally simple. A formulation is presented that allows calculation of phase and group velocities if the wavepacket propagation time and relative phase shift can be measured. The methodology for determining the wavepacket propagation time and relative phase shift from the acquired signals is described. The technique is validated using synthesized signals, finite element model-generated signals and experimental signals from a 3 mm-thick aluminium plate. Accuracies to within 1% are achieved in the experimental measurements.

Metrological Performance of Hybrid Measurement Technique Applied for the Lamb Waves Phase Velocity Dispersion Evaluation

“…As the different frequency components propagate with different velocities after some distance they are concentrated in different UGW signal parts in the time domain [23]. This leads to the change of the waveform, elongation in time and reduction of the amplitude [1], [24], [25].…”

Acoustic Emission Burst Extraction for Multi-Level Leakage Detection in a Pipeline

“…These data-driven approaches are reasonable because the AE signal from leakage is non-stationary and becomes difficult to find in an explicit model for leak detection. However, when the leak occurs at different positions in a pipeline, it would return dissimilar AE sensor signals due to the wave dispersion principle [12]. In addition, the wave attenuation depends on the frequency [13], and the AE signals will be distorted by their own propagation as well as the influence of ambient 2 of 11 noise.…”

Numerical and Experimental Investigation of Guided Wave Propagation in a Multi-Wire Cable

“…Ultrasonic guided wave (UGW)-based nondestructive testing (NDT) techniques are increasingly being used to inspect various multi-wire cables given their high sensitivity, long-range inspection, and full cross-sectional coverage properties. Many studies [8][9][10][11][12][13][14][15][16][17][18] related to guided wave dispersion properties, propagation characterization, signal processing methods, and wire breakage detection in multi-wire cables have been reported.…”