Numerical Modeling of Air-Coupled Ultrasound with EFIT

In this paper the Elastodynamic Finite Integration Technique (EFIT) [1] is applied to an isotropic, inhomogeneous, three media acoustic-elastic problem. We consider three media: an acoustic medium, air, above an elastic layer of acrylic, and another layer of air below the elastic layer. Numerical integration results are presented for various values of the simulation parameters. We generate simulated data by variation of the transducer angle and the presence of planar defects in the acrylic. We compare and discuss the results for both the wavefront images and simulated A-scan data from a second transducer located in the lower acoustic medium.