Abstract
Numerical simulations are useful in the processes of design, development and optimization of transducers for non-destructive testing. In this work, a three-dimensional velocity-stress finite-difference model is presented for the elastic wave propagation in the piezoelectric substrate of a transducer excited by applying an impulsive voltage signal to the transducer electrodes. The allocation of the stress, velocity and electric field components on a staggered grid leads to a stable scheme. The different time scales of both mechanical and electromagnetic waves have leaded previous FDTD models to choose between significant physical simplifications or complicated implicit equations. The model presented here is explicit in all its time domain equations, contains only first order derivatives and is centered in time and space. The results of simulations show remarkable accuracy and stability for the different transducers studied. © 2012 Elsevier B.V.
