Wave propagation in plates can be modelled by solving the equation of motion either analytically, semi-analytically or by means of numerical methods. However effective the proposed models are, the most cost-effective approach, for modelling real aircraft structures of complex geometry and lay-up, is FEM-based simulation with commercially available software such as Abaqus, Ansys. Wave propagation is a dynamic problem, thus very mesh dependant and sensitive to the stable time increment. For modelling of the PZT transducers, depending on the type of solver used (explicit or implicit), there might not be a piezoelectric element readily implemented in the commercial code that takes into account the coupling between the electrical and mechanical properties simultaneously.
Our team has developed “SMART elements” which are used as subroutines with commercial FE code to model wave propagation in composite plate structures. The first fundamental modes are validated against experimental results.
Factors which influence the accuracy of the results are: stable time increment, mesh size, damping factor, damage modelling and directional wave propagation velocity based on the composite layup.