Electrical characteristics of atmospheric air corona plasma by multi-pin electrodes

Abstract

Recently, non-thermal plasma has been widely applied in many fields related to plasma advanced chemical reaction. However, large-scale production of non-thermal plasma is difficult to be achieved in the atmospheric environment. Among other plasma models, corona discharge generated by multi-pin electrodes is one of the good candidates for a massive atmospheric non-thermal plasma production. This paper reports an experimental study on the electrical characteristics of non-thermal atmospheric multi-pin air corona discharges. A plasma model composed of multi-pin anodes with 1, 5, 15, and 64 pins, and a planar counter electrode has been developed. The gap between the electrodes has been 12 mm. Stable streamer glow corona plasma has been generated and observed at the dc-supplied voltage of 14–18 kV. The influences of the electrode number and the supplied voltage on the electrical characteristics of the plasma have been investigated and discussed. The plasma has been found out to be in a self-pulsing discharge mode under every examined experimental condition. The pulsing frequency has increased when the supplied source voltage increased. However, non-periodical pulsing could be observed in the multi-pin electrode cases owing to the multi-discharges from each pin anode. At the same supplied voltage, a greater number of pin electrodes could be sustained with the lower voltage in order to obtain a larger average discharge current. Moreover, more uniform plasma could be achieved, and the transition from glow to arc discharge could be extended due to an interaction of electric field and equipotential lines between the adjacent pin electrodes. © 2019 Praise Worthy Prize S.r.l.-All rights reserved.