Elastic wave propagation in a fluid-loaded anisotropic waveguide with laterally varying properties

摘要

Non-destructive evaluation of heterogeneous materials is of major great interest in industrial and in biomedical fields. In this work, the structure is made of three layers: a laterally heterogeneous anisotropic solid layer between two acoustic fluids. An original method is proposed to solve the wave equation in such structure without using a multilayered model of the plate. This method is based on an analytical solution, the matricant, explicitly expressed under the Peano expansion form. We validate this approach for the study of a fluid-loaded anisotropic plane waveguide with two different fluids on each side. This configuration corresponds to the axial transmission technique for the ultrasound characterization of cortical bone in vivo.