Temporal Behaviour of Micro-discharge in Dielectric Barrier Discharges

A special dielectric barrier discharge (DBD) device consisting of two water electrodes has been designed. The temporal behaviour of the micro-discharge (filament) in the DBD in air at atmospheric pressure is measured by using an optical method. The nonsymmetrical character of the filament is discovered for the first time. We propose an equation regarding the discharge moment by considering the memory effect of accumulated charge and the influence of the fluctuation. The results deduced from the equation give a good explanation to the experimental phenomenon, which show that the decay time constant of the accumulated charges is much larger than the order of 100μs. The relative intensity of fluctuation amplitude is in the range from 2% to 4% under the present experimental conditions.