Numerical characterization of Love waves dispersion in viscoelastic guiding-layer under viscous fluid

Abstract

We present a finite element (FE) based model to accurately investigate the dispersion and attenuation of Love waves in a multilayered structure made of a piezoelectric substrate, a guiding layer, and a viscous fluid. The numerical model solves the general form of the wave equations that includes the materials anisotropy, piezoelectricity, and viscoelasticity. We express the wave equations for elastic waves in a particular formulation in order to solve an eigenvalue problem where the eigenvalue is the complex wavenumber k from which we can derive the phase velocity [ω/Re(k)] and the attenuation rate [Im(k)]. The numerical model enables us to study the effects of the interdigitated electrodes, the materials viscoelasticity and piezoelectricity, and the fluid's viscosity on the wave phase velocity and attenuation. Our FE based model will facilitate optimizing the design of anisotropic piezoelectric platforms for Love waves propagation under viscous fluid loading.