Pre-ionization Methods for Atmospheric Pressure Discharge Controlled by Dielectric Barrier

Dielectric barrier discharge is one of the most usual methods for obtaining atmospheric pressure plasmas. It is proved theoretically that obtaining a uniform dielectric barrier discharge is strongly related to the concentration of seed electrons. Therefore, for producing enough electron concentration under a low electrical field and homogenize the discharge, some pre-ionization methods including accessorial impulse spark discharge, X rays, plasma jet have been employed. The pre-ionization effect of these methods on decreasing the applied voltage for the dielectric barrier discharge and homogenizing the discharge was investigated experimentally.