Spatial wavefield analysis for delamination imaging in composite curved panels

Composite curved panels are widely used in civil aircraft, yet they are susceptible to hidden damage such as delamination due to low-velocity impacts, making effective detection essential. Most existing guided wavefield damage imaging methods rely on Fourier transform-based wavenumber analysis, which processes signals globally and often overlooks local damage features. Moreover, current techniques are primarily developed for flat plates, with limited application to curved panels. To overcome these limitations, this paper proposes a TKEO-wavefield imaging algorithm for detecting hidden delamination in composite curved panels. The approach is based on the principle that delamination induces local wavefield singularities in the spatial domain. By leveraging the Teager-Kaiser Energy Operator (TKEO) to amplify these singularities, a damage image is constructed from the fused TKEO-wavefield energy. Experimental results confirm that the algorithm accurately images hidden delamination, offering a novel solution for damage detection in aerospace composite curved structures.