Simulation of ultrasonic wave propagation in anisotropic cancellous bone immersed in fluid

Cancellous bone at the macroscopic level is known as being a two-phase anisotropic material composed of a solid rod-like or plate-like skeleton filled with viscous fluid. Quantifying the mechanical properties of cancellous bones by using ultrasound techniques should take into account these complexities. This paper proposes a model to investigate the transient ultrasonic wave propagation in a cancellous bone immersed in an acoustic fluid. A finite element time-domain model based on us-wus-w formulation is developed to consider an anisotropic porous medium (Biot’s model) coupled with two acoustic fluids. Some numerical results are shown to illustrate the influence of the bone anisotropy to the reflection and transmission of plane waves in a human cancellous bone specimen.