Synthetic Jet Development For Wall Jet Flow Control

Abstract

The design and construction of synthetic jet actuators for use in active flow control of a turbulent three-dimensional wall jet was investigated experimentally. Seven actuator designs of varying cavity depth and channel height were evaluated based on hot-wire velocity measurements, maximum RMS velocity outputs, and momentum coefficients. Initially, the synthetic jet actuators were driven with sinusoidal frequency sweeps from 10 Hz to 1510 Hz to identify frequencies associated with the strongest velocity output. For each actuator, momentum coefficients were calculated from sinusoidal inputs at the frequencies that produced the strongest jets. Evaluation of these tests showed that the most successful synthetic jet actuator had a cavity depth of 2 mm and channel height of 1.5 mm; it produced the strongest velocity output with momentum coefficients from 0.03-0.05 at input frequencies of 1100-1150 Hz. Synthetic jet actuators capable of providing these momentum coefficients have been shown from the literature to achieve flow control.Index Terms-Synthetic jets, active flow control, threedimensional wall jets, unsteady wall pressure