Delamination Detection of Composite Plate Base on Wavelet Correlation Damage Index of Time Reversal Guided Wave

Abstract

The self-focusing ability of Time Reversal Guided Wave (TRGW) is studied in the damage detection of composite laminates. The finite element modeling of delamination is developed to investigate the potential of TRGW as non-based damage detection system. The similarity index and the damage index are used to evaluate the self-focusing ability at different exciting frequencies, based on which the optimal excitation frequency is determined. The wavelet correlation damage index is proposed based on the correlation between the TRWG wavelet coefficients of response signal and baseline data. By conducting probability analysis of wavelet correlation damage index in the composite plate with delamination, the damage area is reconstructed. Simulation experiment shows that using the proposed index can accurately image the delamination damage with high-resolution, which would provide data support for further imaging research based on time reverse theory.