Propagation of thickness-twist waves in a piezoelectric ceramic plate with unattached electrodes

Propagation of Thickness-Twist Waves in an Infinite Piezoelectric Plate

“…The dispersion relations are complex in general, representing damped waves. The equations reduce to the case of a plate with unattached electrodes and empty air gaps (Qian et al, 2009) and the case of a plate with attached electrodes (Bleustein, 1969) as special cases. The viscosity-induced frequency shift is studied in detail by the the lowest order of perturbation approximation .…”