TY - JOUR
T1 - Nonthermal atmospheric RF plasma in 1-D spherical coordinates
T2 - A parametric study
AU - Sakiyama, Yukinori
AU - Graves, David B.
N1 - Funding Information:
Manuscript received March 7, 2007; revised June 4, 2007. This work was supported by the Japanese Society for the Promotion of Science (JSPS) Postdoctoral Fellowship for Research Abroad. The authors are with the Department of Chemical Engineering, University of California, Berkeley, CA 94720 USA (e-mail: [email protected]; [email protected]). Digital Object Identifier 10.1109/TPS.2007.906129
PY - 2007/10
Y1 - 2007/10
N2 - We present 1-D simulations of atmospheric-pressure RF-excited plasma with two concentric spherical electrodes and the inner electrode powered. The gap distance between the inner and outer electrodes is 1 mm. The gas used is helium with a small amount of nitrogen as an impurity. The coupled continuity equations and electron energy equation are solved with Poisson's equation using the finite element method. In this paper, we particularly focus on the influence of a blocking capacitor, nitrogen concentration, and secondary electrons. In the presence of a blocking capacitor, the self-bias voltage alters sign from negative to positive as the power increases. Reduction of relative nitrogen concentration from 10-3 to 10-6 leads to significant changes in the gas-phase chemistry as well as species flux impacting the outer electrode. Secondary electrons turned out to play a minor role in the transition from the corona to glow modes. We also show that the directed ion kinetic energy distribution to the outer electrode largely depends on the discharge mode.
AB - We present 1-D simulations of atmospheric-pressure RF-excited plasma with two concentric spherical electrodes and the inner electrode powered. The gap distance between the inner and outer electrodes is 1 mm. The gas used is helium with a small amount of nitrogen as an impurity. The coupled continuity equations and electron energy equation are solved with Poisson's equation using the finite element method. In this paper, we particularly focus on the influence of a blocking capacitor, nitrogen concentration, and secondary electrons. In the presence of a blocking capacitor, the self-bias voltage alters sign from negative to positive as the power increases. Reduction of relative nitrogen concentration from 10-3 to 10-6 leads to significant changes in the gas-phase chemistry as well as species flux impacting the outer electrode. Secondary electrons turned out to play a minor role in the transition from the corona to glow modes. We also show that the directed ion kinetic energy distribution to the outer electrode largely depends on the discharge mode.
KW - Atmospheric pressure
KW - Microplasma
KW - Numerical analysis
KW - Spherical coordinates
UR - https://www.scopus.com/pages/publications/35348866231
UR - https://www.scopus.com/inward/citedby.url?scp=35348866231&partnerID=8YFLogxK
U2 - 10.1109/TPS.2007.906129
DO - 10.1109/TPS.2007.906129
M3 - Article
AN - SCOPUS:35348866231
SN - 0093-3813
VL - 35
SP - 1279
EP - 1286
JO - IEEE Transactions on Plasma Science
JF - IEEE Transactions on Plasma Science
IS - 5 I
ER -