Self-consistent fluid modeling and simulation on a pulsed microwave atmospheric-pressure argon plasma jet

Abstract

In present study, a pulsed lower-power microwave-driven atmospheric-pressure argon plasma jet has been introduced with the type of coaxial transmission line resonator. The plasma jet plume is with room air temperature, even can be directly touched by human body without any hot harm. In order to study ionization process of the proposed plasma jet, a self-consistent hybrid fluid model is constructed in which Maxwell's equations are solved numerically by finite-difference time-domain method and a fluid model is used to study the characteristics of argon plasma evolution. With a Guass type input power function, the spatio-temporal distributions of the electron density, the electron temperature, the electric field, and the absorbed power density have been simulated, respectively. The simulation results suggest that the peak values of the electron temperature and the electric field are synchronous with the input pulsed microwave power but the maximum quantities of the electron density and the absorbed power density are lagged to the microwave power excitation. In addition, the pulsed plasma jet excited by the local enhanced electric field of surface plasmon polaritons should be the discharge mechanism of the proposed plasma jet.

Electron characterization in weakly ionized collisional plasmas: from principles to techniques

“…Because of the limited use of electron diagnostics for high-pressure weakly ionized plasmas, numerical studies, particle-in-cell Monte Carlo collision simulations [105] and hybrid-fluid models [106,112,113] have provided profound insights into the electron kinetics and characteristics of rf capacitive discharges at atmospheric pressure. However, experimental investigation is still important.…”

Discharge characteristics of atmospheric pressure pulsed microwave He/N2 plasma jet

“…Then, highenergy electrons are accelerated by the electric field collide to produce excited and ionized He products. Meanwhile, they can also interact with each other and produce two high-energy quasi-stable particles (He [12 3 S 1 ] 19.82 eV, He [2 1 S 0 ] 20.6 eV). Finally, the central He jet channel forms in this zone.…”

“…Atmospheric pressure plasma jet (APPJ), especially for microwave plasma jet, has a low working temperature, contains rich active particles, small ozone, and NO 2 emission and attracts great interest in wound healing, sterilization and disinfection, surface modification, and sewage purification. [1][2][3][4][5][6][7][8][9][10][11][12] Monoatomic gases, He and Ar, are often selected as the discharge working gas to generate APPJ, because the ionization efficiency of polyatomic gas is low. Many studies have been conducted on the discharge characteristics of APPJ produced by He and Ar.…”

The Double-Spiral Antenna for the Production of Microwave Plasma Jets

“…ω p = (e 2 n e /ε 0 m e ) 1/2 is the angular frequency of the plasma in metal, γ is the damping rate, and n e is the electron density of the metal. Considering ω p /γ 1 (e.g., ω p = 1.2 × 10 16 rad · Hz and γ = 1.45 × 10 13 Hz for silver in visible frequency bands), the traditional approximation expression for the wavelengths of SPPs has been given by [9], [20] …”

“…MPJ is used for the metal surface processing [8]. A pulsed low-power microwavedriven atmospheric-pressure argon plasma jet with a type of coaxial transmission line resonator is introduced [9].…”