Formation mechanisms of striations in a filamentary dielectric barrier discharge in atmospheric pressure argon - dataset

The results of the modelling of a filamentary dielectric barrier discharge (DBD) in argon at atmospheric pressure obtained using a time-dependent and spatially two-dimensional fluid-Poisson model in axisymmetric geometry are provided in this dataset. The model was employed to investigate the formation mechanisms of the striations along the discharge channel in a one-sided DBD arrangement with a 1.5 mm gap powered by a sinusoidal high voltage applied at the metal electrode. The discharge conditions were chosen to resemble the experimental conditions for which striations have been observed. It was found that the striations form in both half-periods during the transient glow phase, which follows the streamer breakdown phase. The modelling results showed that the distinct striated structures feature local spatial maxima and minima in charged and excited particle densities, which were more pronounced during the positive polarity. Their formation was explained by a repetitive stepwise ionisation of metastable argon atoms and ionisation of excimers, causing a disturbance of the spatial distribution of charge carriers along the discharge channel. The results emphasise the importance of excited states and stepwise ionisation processes on the formation of repetitive ionisation waves, eventually leading to striations along the discharge channel.