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The design of the discussed fluid jet actuator followed two ideas: a double-acting operation of reciprocating pumps, and a hybrid synthetic jet (HSJ) actuation. The entire actuator consists of two basic parts, namely the front (central) and rear chambers, from which fluid is displaced by the opposite sides of the same diaphragm. The actuator operates in a double-acting (antiphase) regime with air as the working fluid. The central chamber generates the standard (zero-net-mass-flux) axisymmetric synthetic jet (SJ), while the rear chamber generates system of several non-zero-net-mass-flux HSJs arranged around the central SJ. A number of variants of HSJs with different geometry were designed, manufactured and tested. Their behavior was investigated experimentally using the smoke visualization, reaction force measurement, hot-wire anemometry, and naphthalene sublimation technique. The tests confirm the efficiency of the present design.

This paper deals with a new design of a hybrid synthetic jet actuator (HSJA), which is based on a novel fluidic diode. Two fluidic diodes were tested using pressure-drop measurements with air as the working fluid, and their diodicities were evaluated. A greater diodicity was achieved with the new diode design. Two outlet nozzles of the HSJA were tested (shorter and longer), and the velocity resonance curves were evaluated using hot-wire measurements at the outlets of the nozzles. Volumetric efficiency of the HSJA was evaluated as function of the operating frequency. The greatest efficiency was achieved at the second resonant frequency of the actuator with the longer nozzle.