Spatial and temporal evolution of a dielectric barrier discharge

Experimental study of spatial and temporal evolution of a dielectric barrier discharge (DBD) during a single current pulse is reported. The discharge light emission has been imaged using a high-speed intensified charge-coupled device camera. The time-resolved light emission data have been combined with the discharge current and applied voltage waveforms measurements. The discharge behavior has been found to be dependent on the external circuit impedance and bandwidth. Being nonstationary in principle, the DBD can exhibit both time evolution and development over the electrode area. For a typical DBD setup with flat parallel electrodes, the discharge breakdown occurs in the electrode's central part; then, the plasma column expands to the electrode's peripheries and gradually fills up the entire electrode area. The powering system should be able to provide enough current value during the discharge glow to achieve a simultaneous breakdown over the whole electrode area. In this case, the discharge appears over the entire electrode's area and the plasma column exhibits temporal evolution only. The measured discharge characteristics for different power supply architectures had shown the evidence of a "normal current density" effect in DBD glow. (c) 2008 American Institute of Physics.