RECTANGULAR PIEZOELECTRIC PLATE LOADED ON EACH FACE - A 3-DIMENSIONALAPPROACH

This paper deals with the vibration mode determination of a rectangula r plate loaded on each face. The resonant frequencies, the mechanical displacement and the electrical impedance of the plate are calculated using a three-dimensional approach based on the plane wave propagation along each coordinate axis. Then, the constitutive piezoelectric equa tions reduce and by introducing the relevant boundary conditions - tha t is, the stresses and particle displacements are continuous - a 7 x 7 linear matrix system is obtained. Solving this system yields the part icle displacements in terms of the load impedances located on the samp le faces. The electrical impedance of the sample can also be easily co mputed. It is shown that due to lateral coupling, there is no nodal pl ane inside the sample and the material losses used are less than those introduced with the one-dimensional approach.