Measurement of the charge distribution deposited on a target surface by an annular plasma synthetic jet actuator: Influence of humidity and electric field

In this paper, an investigation on an annular Plasma Synthetic Jet Actuator (PSJA) utilizing a Surface Dielectric Barrier Discharge (SDBD) is reported. The work is focused at an investigation of the electric charges transported by the jet produced by the actuator and deposited on a target. Particularly, an assessment of the various factors that may affect the charge deposit process has been carried out. Experiments have been performed in a controlled environment with different electric configurations. This allowed to evaluate how the humidity rate affects and the dynamics of the electric charge build-up process. It was observed that humidity rate weakly affects the charge deposition, being the most notable effect an increase of the deposition time for higher humidity rate. Moreover, the performances of two different power supply systems, working at different voltage and frequency conditions, were compared. The two supplies have been set up do feed the actuator with the same power, in order to assess which voltage-frequency condition is more efficient at depositing electric charge on the target. It was observed that a higher applied electric field produces higher charge deposition rates.