Abstract Summary
This paper presents a fast and reliable model, for analysing the effect of localised damage on waveguides and obtaining all the range of dispersion curves for wave propagation. The model is based on modelling a finite section of the waveguide using the Finite Element Method (FEM) and applying the Floquet boundary conditions. These boundary conditions ensure the implantation of periodicity in the displacement field. Then, the eigenvalue problems are solved to obtain mode shapes and corresponding natural frequencies for different wavelengths. This method provides a physical based knowledge of how damages interact with wave modes. Although the eigenvectors obtained may be very localised, they will still result in some interaction between the damage and the propagating wave modes. Finally, the phase and group velocity curves have been studied for various composite laminates in pristine conditions as well as those with delamination. The effect of damage on the shape of individual wavefronts has also been studied with the help of slowness curves. The effect of damage on the shape of individual wavefronts has also been studied with the help of slowness curves.
