Vector Control of Synthetic Jets Using an Asymmetric Slot

This is a fundamental study on the jet vectoring control by means of adjusting the synthetic jet Strouhal number (frequency) without slot shape change with time in actuators. This work involved introduction of asymmetric slots with various beak lengths in free synthetic jets for various frequencies, experimentally and numerically. Furthermore, the behavior of synthetic jets was compared with that of the continuous jets. In our experiment, velocity measurements for both types of jets were performed using a hot-wire anemometer with an I-type probe and a traverser, and flow visualization for observing the behavior of the jets was performed using the smoke wire method. Through the experiment, typical flow patterns and time-averaged velocity distributions of synthetic jets for various beak lengths and Strouhal number were demonstrated. The time-averaged velocity was measured at a reference point on the slot centerline to evaluate the degree of the bend of the jets and the obtained data was used in the Strouhal number-beak length map.