Abstract: In order to get the characteristics of flow field and the influence of some parameters of a synthetic jet, experiments and numerical simulations are performed. During the simulation, moving grid technique is used for modeling the periodic movement of the piezoelectric membrane so that the coupled computation of the field cavity and the external flow field can be realized, the flow phenomena agree well with the experiment results. The results show that: the centerline velocity of the synthetic jet takes on up-down tendency varying with the axial distances and accelerates to a maximum at a distance of approximately 10 slot-widths; the best actuating signal for synthetic jet actuator is square wave, at which the velocity of the synthetic jet can achieve to the maximum; the velocity of the synthetic jet increases with the imput voltage for actuator until it achieves 175 V; there are two resonance frequencies for actuator of the synthetic jet, 340 Hz and 1 kHz, the optimal resonance frequency is 1 kHz; The improvement of the velocity of synthetic jet is remarkably influenced by the amplitude of the actuator’s membrane. The velocity of the synthetic jet will improve if the ratio of height to diameter of the actuator is small. The results provide theoretic foundations for the experimental parameters and the optimizing design of the experimental parts.

Key words: Actuating factors, Geometry parameters, Optimizing design, Resonance frequency, Synthetic jet