Inspection of subsurface defects in CFRP-plate with using point-source constrained partial differential equation

Elastodynamic response of orthotropic laminate composite structures subjected to an incident wave front is evaluated based on the integral representations in terms of the spatial impulse response. Being different from the conventional TOF or TOFD method, the spatial impulse response representation keeps information about the source and gives an opportunity for a quantitative near- and far-field analysis of the propagating wave field. This study, therefore, discusses a novel imaging method based on the point-source constrained partial differential equation (PSC-PDE) in order to reconstruct the silhouette of the subsurface defects. A point source response on the 2-dimensional space is analyzed mathematically and several acoustical experiments are performed to show accuracy and applicability of our proposed approach for imaging of defects in a plain woven CFRP plate.