Mode transition induced by back‐breakdown of the gliding arc and its influence factors

Abstract

Gliding arc is a mostly used non‐equilibrium plasma generation method whose characteristic is affected by the back‐breakdown phenomenon. Mode transition induced by back‐breakdown of the gliding arc is studied in this work and effects of gas flow rate, applied voltage, electrode parameters on mode transition were studied. Experimental results show that there are two typical modes during the development of the gliding arc. Mode A comprises periodicitical development of the arc from the minimum gap breakdown to the longest extinguishment, while the arc in mode B continues to produce a back‐breakdown at the ends of the electrodes. As the flow rate descends, the gliding arc gradually changes from mode A to B. It is the decrease of the arc velocity caused by lower flow rate leads to the occurrence of back‐breakdown, which generates mode B. Smaller electrode opening angle, shorter length and wider minimum gap reduce the gliding speed, so that arc is more likely to enter mode B. As the applied voltage is increased, enhancing of the electric field strength on the breakdown path of the back‐breakdown and thickening of the arc's diameter allow the gliding arc to enter mode B at a higher arc speed.