Guided wave based nondestructive analysis of localized inhomogeneity effects in an advanced sandwich composite structure

In this paper, we present a nondestructive analysis of localized inhomogeneity effects on guided wave propagation in an advanced sandwich composite structure. In the process, guided wave dispersion curves were semianalytically determined for the structure to accurately identify different wave modes in experimental and numerical analysis signals. Finite element simulation of wave propagation in the target structure was then carried out in ABAQUS and validated with the experiment. Significant influences on the wave mode amplitudes were observed due to the presence of a localized inhomogeneity in the structure. An inhomogeneity identification strategy was prepared based on the amplitude changes in the registered guided wave signals from a predefined piezoelectric transducer network. The influence of varying elastic modulus and mass-density of the inhomogeneous region on the wave mode amplitudes and the corresponding inhomogeneity-index magnitudes were also studied