Interelectrode microwave glow discharge in atmospheric-pressure argon flow

Abstract

The spatio-temporal structure and plasma parameters of a new type of glow discharge – atmospheric-pressure interelectrode microwave discharge in gas flow – were studied experimentally and numerically. A multi-electrode coaxial-type cold plasma torch developed for large-area surface treatment was used as a gas discharge device. The torch was supplied with microwave power (2.45 GHz, ∼100 W) via a coaxial cable by a typical wave-guide plasmatron. Self-sustained glow discharges were excited between the round ends of the rod-like electrodes and inner wall of the cylindrical discharge chamber near the outlet. The filamentation of the discharge channel in the near-electrode regions was detected by high-speed video filming. The dendritic self-similar (fractal) character of the filaments’ structure was revealed and analyzed. The branching factor and fractal dimension of this structure were estimated as 3 and 1.1–1.3, respectively. Using discharge gas temperature T_g = 1200±100 K, as determined from the emission spectroscopy measurements, the following discharge plasma parameters were obtained from numerical calculations: electron temperature T_e = 1.14 eV and concentration n_e∼10^21-10^22 m^(-3), conductivity σ ∼ 400 Ω^(-1)m^(-1) , current density j ∼ 10^6 A/m^2, and electric field strength E ∼ 10^4 V/m.

Advancements in Plasma Agriculture: A Review of Recent Studies

“…Microwave plasma torches are commonly used in material processing applications, chemical synthesis, environmental remediation, and PAW production [57][58][59][60][61][62]. Low-energy APPJs are utilized for precise surface treatments, cleaning, and activation, as well as in fields such as plasma medicine, including wound healing, sterilization, and cancer treatment [63][64][65].…”

Two-term Boltzmann approximation versus Monte-Carlo simulation: effect of magnetic field

“…Nevertheless, TTB is widely used to calculate the various types of gas discharges (streamers [33,34], glow discharges [35,36], sparks [37], DBD [38,39], corona discharges [40,41]), including in the near-electrode regions, where abnormally high electric fields and their gradients are. In this case, there is no opportunity to study the phenomena caused by the difference in longitudinal and transverse diffusion.…”