Spatiotemporally resolved characteristics of AC three-dimensional rotating gliding arc at atmospheric pressure

Based on gliding arc discharge, a novel aero-engine combustor head is designed, which can realize three-dimensional rotating gliding arc discharge in turbulent flow field at atmospheric pressure. The spatiotemporally resolved characteristics and discharge modes of gliding arc discharge are studied, including gliding discharge (G-D) mode, breakdown discharge (B-D) mode, multi-cycle B-D (MB-D) mode, short-cutting discharge (SC-D) mode. And the conversion between different discharge modes are discussed by using optical and electrical parameters synchronous observation. In the G-D mode, the discharge voltage and current show sinusoidal variation, and the current amplitude is about several 100 mA. In B-D mode and MB-D mode, the current waveform appears as nanosecond spike, and the peak value can reach several amperes. The interaction between turbulent flow and electric field can lead to SC-D mode, which reduces the arc length suddenly and changes the discharge path of the arc. Air flow and input power will affect the discharge mode of the gliding arc. In the G-D mode, the arc will change to B-D mode as the length increases. When the power supply energy is enough to maintain the arc gliding, the arc in B-D mode will also change to G-D mode. In different discharge modes, the discharge power of the arc will also be affected by the air flow and power supply energy.