Characteristics of Atmospheric Room-Temperature Argon Plasma Streams Produced Using a Dielectric Barrier Discharge Generator With a Cylindrical Screwlike Inner Electrode

In this paper, an innovative coaxial-type dielectric barrier discharge plasma generator is proposed to produce the large-volume and visibly uniform cold argon plasmas at atmospheric pressure by enhancing the local intensity and uniformity of the electric field simultaneously with the aid of a cylindrical screwlike inner electrode configuration. The experimental measurements show that the discharges transit from the initial stage after breakdown to the stable stage through a transitional stage and finally reach an unstable discharge stage with the increase of the applied voltage. The estimated values of the electron temperature and the number density of the gas discharge plasmas in the electrode region vary in a small range, i.e., 8.0-8.9 eV and (4.6-6.4) × 10¹¹ cm^-3, with increasing the applied voltage. Moreover, the plasma streams are quite uniform in the radial direction with a low gas temperature ( ~ 300 K) and an abundance of chemically reactive species in the stable discharge stage, which will be potentially a useful tool for the treatment of the heat-sensitive materials.