Finite element model for nonlinear shear wave propagation in nearly- incompressible soft tissues
Abstract
Nonlinear viscoelastic Landau's theory which is widely used in acoustical physic field is introduced into a finite element formulation. It is designed to model the nonlinear behaviour of finite amplitude shear waves in soft solids, typically, in biological tissues. In experiments of transient elastography [1], the nonlinear behaviour of shear waves is generally presented in spectral domain, it has been observed that, in plane shear wave propagation, the cubic nonlinearity in high amplitude wave at the frequency of f generates odd harmonics at 3f, 5f. In this work, the numerical models based on these experiments are presented. The simulation are carried out by the selective mass scaling method presented in [2], the results show a good agreement with the experimental study (see Figure). Spectra of the vertical velocity v.s. propagation depth References [1] Jacob X, Catheline S, Gennisson JL, Barri`ere C, Royer D, Fink M. Nonlinear shear wave interaction in soft solids.
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