Air Flow in a Small Gap between a Bending Vibrator and a Reflector

In this paper we present numerical simulations and experiments of air flow iduced in a gap between a piezoelectric bending vibrator and a reflector. Half of the simulation is based on the coupled analysis of piezoelectric elastic vibration and sound field using finite element method (FEM). The other half is the numerical fluid dynamics modeled Using FEM where the driving forces are calculated on the basis of the acoustic streaming theory. One-directional streaming in the gap is predicted using, the simulation and was Successfully obtained in the experiments by introducing asymmetry both in the vibration distribution of the vibrator and the sound field. Air flow velocity of over 0.5 m/s was achieved using a vibrator of 30 x 20 mm(2) with an electrical power consumption. [DOI: 10.1143/JJAP.47.4276]