Pattern formation in dielectric barrier discharge in air at atmospheric pressure

Pattern formation has been observed in dielectric barrier discharge in air at atmospheric pressure by using water electrodes. These patterns include regular patterns(hexagon-like structure and stripe structure) and irregular patterns. It has been found that the filament density decreases with the thickness of the dielectric and the gas gap spacing increase. But it increases with both voltage and frequency increase. The dependence of the filament density on the applied voltage has been studied by analyzing the spatial correlation function in pattern formation.