Analysis of coupled vibration modes in piezoelectric disks

Abstract

Coupling modes in piezoelectric disks of various aspect ratios D/t were analyzed. Behavior of piezoelements was simulated using finite elements method. In this paper there are presented characteristics of influence of D/t to the impedance magnitude in frequency range. Modes of vibrations were identified using visualization of displacements. It was demonstrated, that identification of radial harmonic number “tracing” the resonant frequency can give wrong results. The characteristics of displacement at center, edge and lateral surface of piezoelement are presented also. It was found aspect ratios D/t when electromechanical coupling factor of coupled radial-bar mode is maximal. Analysis of piezoelement in water confirmed that these aspect ratios are not influenced by radiation of ultrasonic waves.