Dispersion Compensation Method for Lamb Waves Based on Measured Wavenumber

Abstract

In this study, a delta wavenumber dispersion compensation (∆K-DC) method was developed and applied, not only with the theoretical wavenumber but also with the measured wavenumber. Dispersion compensation can be achieved by the following steps: relative wavenumber measurement, traveling distance estimation, phase compensation, and wave correction. The feasibility of ∆K-DC with the theoretical wavenumber and measured wavenumber was validated with a high-dispersive A0 mode in a 2 mm steel plate experiment. The results showed that phase spectrum measurement was an effective method to construct the wavenumber curve, the propagation distances estimated by SAP2 were very accurate, and the dispersive signals can be compensated perfectly by applying the phase compensation and wave correction methods for each wavepacket. The present results highlight the application of ∆K-DC on dispersion compensation without any material parameters of a waveguide.