Characteristics of gliding arc plasma and its application in swirl flame static instability control

Abstract

Based on an experimental system involving a pulsating airflow burner and gliding arc generator, the characteristics of gliding arc plasma at different flow rates and its control effect on the static instability of the swirl flame have been studied. The current, voltage, and power wave forms, as well as the simultaneous evolution of plasma topology, were measured to reveal the discharge characteristics of the gliding arc. A bandpass filter was used to capture the chemiluminescence of CH in the flame, and pressure at the burner outlet was acquired to investigate the static instability. Experimental results showed that there were two different discharge types in gliding arc plasma. With the low flow rate, the glow type discharge was sustained and the current was nearly a sine wave with hundreds of milliamperes of amplitude. With the high flow rate, the spark type discharge appeared and spikes which approached almost 1 ampere in 1 μs were found in the current waveform. The lean blowout limits increased when the flame mode changed from stable to pulsating, and decreased significantly after applying the gliding arc plasma. In pulsating flow mode, the measured pressure indicated that static instability was generated at the frequency of 10 Hz, and the images of flame with plasma showed that the plasma may have acted as the ignition source which injected the heat into the flame.