Process of AC multichannel gliding arcs discharge in rotational flow

摘要

In order to solve the problem of small and asymmetrical plasma area of the gliding arc (GA) in the chemical treatment process, a plasma actuator driven by alternating current (AC) with a frequency of 23.2kHz was designed to multichannel gliding arcs (MGAs) in a rotational air flow at atmospheric pressure. The spatiotemporally resolved discharge characteristics of the MGA, including long-length breakdown, long-term extinction and typical breakdown features, were investigated combining optical and electrical diagnostic methods simultaneously at a flow rate of 250 SLM (standard liter per minute). The response characteristics of MGA under different flow rates were analyzed. On average, the MGA exhibit 48.8% more discharge power compared to traditional single-channel GA under flow rates of 50-250 SLM, which is due to the GAs continual existence at long-length state, representing better stability of the MGA plasma actuators. It was observed that the frequency of typical breakdown and long-term extinction increased as the flow rate accelerated, and the maximum height the GA could reach decreased with the number of channels increasing from 1 to 5, which can be attributed to the power decline of separate channels of GAs at 50 SLM. It was also found that MGA showed a broader plasma distribution of low electron temperature than traditional single-channel GA.