Simulation of Piezoelectric Devices by Two- and Three-Dimensional Finite Elements

Abslract--A method for the analysis of piezoelectric media hased o n finite element calculations is presented in which the fundamental electroelastic equations gokerning piemelectric media are solved numerically.Theresultsohtained h! thisfinite-elementcalculationscheme agreewiththeoreticalandexperimentaldatagiven in the literature. The method is applied to the bihrational anal!sis of piezoelectric sensors and actuators with arbitrary structure. Natural frequencies nith related eigenmodes of those devices as well as their re.;ponses to Iarious time-dependent nlechanical or electrical excitations are computed. The theoreticallycalculatedmodeshapes of piezoelectric transducersand their electrical impedances agree quantitativelj with our re5pective interferometric and electric measurements. The simulations are used to optimize piezoelectric devices such as ultrasonic transducers for medical imaging. The method also provides deeper insight into the physical mechanism5 of acoustic wabe propagation in piemelectric media.