SAFE-PML approach for modal study of waveguides with arbitrary cross sections immersed in inviscid fluid

Ultrasonic guided wave is an important non-destructive tool for large area inspections of immersed structures as well as fluid characterizations. In this paper, a numerical tool is developed for the modal study of immersed waveguides with arbitrary cross sections, by coupling the Semi-Analytical Finite Element (SAFE) method with Perfectly Matched Layer (PML). The model is first validated on waveguides with regular cross sections with analytical solutions. It is then applied to immersed waveguides with rectangular cross sections and L-shaped cross sections, showing the potential of guided waves for NDT applications and fluid characterizations.