Investigations on an Atmospheric Dielectric Barrier Discharge Plasma Jet With a Concentric Wire-Mesh Cylinder Electrode Configuration

An atmospheric-pressure plasma jet generated by a sinusoidal power input of tens of kilohertz and designed with a concentric wire-mesh cylinder electrode is characterized in this paper. Effects of gas flow rate on the length of plasma jet have been investigated, and the plasma jet is seen to have three different modes varied with the gas flow. The jet temperature is measured by fine-structure fitting of the emission bands of UV OH, molecules, and the Boltzmann plot method, and in comparison with the data obtained by an optical-fiber thermometer. In addition, the electron density in the generation region is diagnosed by stark broadening. Plasma bullet properties such as velocity, luminosity, their time of formation and extinguishment, and traveling distance are studied with variation of the applied voltage, gas flow rate, and operating frequency of power supply. Notably, the bullet velocity is found to have decreased with the applied voltage but increased with the operating frequency. Furthermore, the maximum velocity is reached earlier for lower gas flow rates and higher applied voltages, but its value is independent of the gas flow rate.