Dynamic behavior of a rotating gliding arc plasma in nitrogen: effects of gas flow rate and operating current

The effects of feed gas flow rate and operating current on the electrical characteristics and dynamic behavior of a rotating gliding arc ( RGA ) plasma codriven by a magnetic field and tangential flow were investigated. The operating current has been shown to significantly affect the time-resolved voltage waveforms of the discharge, particularly at flow rate=2 l min^-1 . When the current was lower than 140 mA, sinusoidal waveforms with regular variation periods of 13.5–17.0 ms can be observed ( flow rate = 2 l min^-1 ). The restrike mode characterized by serial sudden drops of voltage appeared under all studied conditions. Increasing the flow rate from 8 to 12l min^-1 (at the same current) led to a shift of arc rotation mode which would then result in a significant drop of discharge voltage (around 120 – 200 V). For a given flow rate, the reduction of current resulted in a nearly linear increase of voltage.