Synthetic jet actuators for flow control

The synthetic jet actuator is a novel means of applying flow control that lends itself to incorporation into micro- electro-mechanical systems. Experimental and computational studies of the flow generated by this actuator are presented and discussed. The synthetic jet is seen to resemble a steady turbulent jet. Self-similarity is, however, achieved closer to the orifice in the case of the synthetic jet, and this is consistent with the observation from the numerical simulations that a main vortex is trapped close to the orifice. This main vortex merges with the secondary vortex that is generated at the circumference of the orifice during each cycle of oscillation of the actuator membrane. The effect of synthetic jets on wake flows and flames has also been examined. Preliminary results of these investigations suggest that synthetic jets can significantly reduce drag and enhance mixing.