Title :
Bullet Velocity Distribution of a Helium Atmospheric-Pressure Plasma Jet in Various N2/O2 Mixed Ambient Conditions
Author :
Su-Jeong Kim ; Sung-Young Yoon ; Gon-Ho Kim
Author_Institution :
Dept. of Energy Syst. Eng., Seoul Nat. Univ., Seoul, South Korea
Abstract :
Spatial bullet velocity distribution of an atmospheric-pressure plasma jet (APPJ) in the N2 and O2 mixture gas were investigated by varying the gas mixing ratio. The bullet propagation from the discharge tube exit was observed by an ICCD and the bullet velocity had three phases as the acceleration, the constant velocity, and the deceleration phases. These velocity phases were analyzed using the simple and analytical fluid model. The density of neutrals and the transport parameters of electron were obtained from CFD-ACE+ and BOLSIG+. It can be envisaged that each of three propagation phases are influenced closely by the Penning ionization effect of helium metastable on N2 and O2 ionization, the induced electric field in an APPJ discharge tube, and the formation of negative oxygen molecules, respectively. It is expected that this paper explains the effects of grounded or floated target under the jet on bullet and vice versa.
Keywords :
Penning ionisation; discharges (electric); helium; plasma collision processes; plasma density; plasma diagnostics; plasma jets; plasma simulation; plasma transport processes; BOLSIG+; CFD-ACE+; He; ICCD; Penning ionization effect; acceleration phase; analytical fluid model; bullet propagation; constant velocity phase; deceleration phase; discharge tube exit; electron transport parameters; floated target effect; gas mixing ratio; grounded target effect; helium plasma jet; induced electric field; negative oxygen molecule formation; neutral density; nitrogen ionization; nitrogen-oxygen gas mixture; nitrogen-oxygen mixed ambient conditions; oxygen ionization; pressure 1 atm; propagation phases; spatial bullet velocity distribution; Discharges (electric); Electrodes; Electron tubes; Helium; Ionization; Plasmas; Space charge; Atmospheric-pressure plasmas; plasma diagnostics; plasma diagnostics.;
Journal_Title :
Plasma Science, IEEE Transactions on
DOI :
10.1109/TPS.2015.2428721