Open AccessCharged particle kinetics and gas heating in CO2 microwave plasma contraction: comparisons of simulations and experiments
Author(s) -
Luca Vialetto,
Alex van de Steeg,
Pedro Viegas,
S. Longo,
G.J. van Rooij,
M.C.M. van de Sanden,
Jan van Dijk,
P. Diomede
Publication year - 2022
Publication title -
plasma sources science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 108
eISSN - 1361-6595
pISSN - 0963-0252
DOI - 10.1088/1361-6595/ac56c5
Subject(s) - plasma , ion , chemistry , ionization , atomic physics , electron temperature , electron , electron density , microwave , kinetics , physics , organic chemistry , quantum mechanics
This work investigates kinetics and transport of CO 2 microwave plasmas through simulation results from a 1-D radial uid model and experiments. Simulation results are validated against spatially resolved measurements of neutral species mole fractions, gas temperature, electron number density and temperature obtained by means of Thomson and Raman scattering diagnostics, yielding good agreement. As such, the model is used to complement experiments and assess the main chemical reactions, mass and energy transport in diuse and contracted plasma regimes. From model results, it is found that, as pressure is raised, the inhomogeneous gas heating induces signicant gradients in neutral and charged species mole fractions proles. Moreover, the transition from diuse to contracted plasma is accompanied by a change in the dominant charged species, which favours electron-ion recombination over dissociative attachment. Associative ionization rates increase in the plasma core from diuse to contracted regime. These processes contribute to the increase in the peak electron number density with pressure, that determines radial plasma contraction.