Acoustic-structural coupling in the frequency response of synthetic jet devices

This paper presents a general lumped element mathematical model of the operation of a synthetic jet actuator with a piezoelectric driver in order to investigate the frequency response of the device. The model shows that the system behaves as a two-coupled oscillators device. Analytical expressions are given in order to predict the two peak frequencies, corresponding to the modified Helmholtz and first-mode structural resonance frequencies. The model has been validated experimentally through systematic experimental tests carried out on three devices having different mechanical and geometrical properties. A very strict agreement between numerical and experimental findings is found.