Study on the diameter and discharge duration of filament in dielectric barrier discharge in Air/Argon

摘要

The spatial-temporal correlation in dielectric barrier discharge is difficult to be studied in the mixed gas of air and argon. In this paper, a simple optical method is introduced to study the temporal correlation intensity between micro-discharge filaments in dielectric barrier discharges at different air concentration in mixed gas of air and argon. The relation of the breakdown voltage and air concentration (χ) is measured. It's found that the breakdown voltage increases as the air concentration increasing. The experimental results show that the diameter and discharge duration of the filament decrease with the air concentration increasing, at the same time the coherence of the discharge moments of the filaments weakens with the air concentration increasing. The experimental results can be explained with the theory of electron drifting. In addition, the accumulated charges on dielectric surface created by the filament discharge create a field within very time when the duration is small, which against the filament breakdown in its neighboring region. So the coherence of the discharge moments of the filaments can't be realized. While the accumulation of the surface charges will last a long time when the duration of the filament discharge is big, the breakdown can take place in the neighboring region of the filament in the duration, which would be the factor to the coherence of the discharge moments.