Title :
OH radical measurement in a pulsed arc discharge plasma observed by a LIF method
Author :
Ono, Ryo ; Oda, Tetsuji
Author_Institution :
Dept. of Electr. Eng., Tokyo Univ., Japan
Abstract :
Hydroxyl radicals generated by a pulsed arc discharge were measured by laser-induced fluorescence (LIF) with a tunable KrF excimer laser. It was shown that not only OH but excited O2 (O2 *) and excited NO (NO*) had absorption lines within a tunable range of the KrF laser, so that LIF signals of O2 * and NO* were observed as well as OH signals. It was demonstrated that OH could be detected without disturbance by LIF signals of O2* or NO* through the A-X(3,0):P2(8) excitation; OH density was measured under various conditions in the post-discharge region. The influences of humidity, discharge current, and O2 concentration on OH density and OH decay rate were studied in H2 O/O2/N2 mixture. The results provided some possible channels of OH production and reaction with other molecules in humid air. The absolute density of OH was estimated
Keywords :
arcs (electric); excimer lasers; fluorescence; oxygen compounds; plasma chemistry; plasma diagnostics; spectrochemical analysis; A-X(3,0):P2(8) excitation; H2O-O2-N2; H2O/O2/N2 mixture; KrF; LIF method; NO; O2; O2 concentration; OH; OH decay rate; OH density measurement; OH radical measurement; absolute density; absorption lines; discharge current; excited NO; excited O2; humidity; hydroxyl radicals; laser-induced fluorescence; post-discharge region; pulsed arc discharge plasma; tunable KrF excimer laser; Absorption; Arc discharges; Density measurement; Fluorescence; Laser excitation; Measurement by laser beam; Optical pulse generation; Plasma measurements; Pulse measurements; Tunable circuits and devices;
Journal_Title :
Industry Applications, IEEE Transactions on
