A modelling approach for virtual development of wave based SHM systems

Within the last decade many SHM approaches utilizing elastic waves have been developed. In case of thin-walled structures especially guided waves - excited and sensed by surface-bonded or integrated piezoelectric elements - have shown a high potential. Despite of considerable efforts, some fundamental questions are still to be tackled for industrial application. One way of improving this situation and gaining a deeper insight into wave propagation and wave scattering phenomena is a detailed modelling of the systems. Very promising for this purpose seems to be the spectral element method. This contribution presents a modelling approach for flat shell CFRP structures based on this methodology. Special attention is paid to the incorporation of delamination type damage. The delaminated area is modelled using separated upper and lower elements with conforming meshgrid. After introducing a contact formulation that preserves the high computational efficiency of the approach, the influence of contact on the local displacement field within the delaminated area is analysed. The simulation is validated by comparison to experimental data.