N2(A) vibrational kinetics in streamer discharges: effect of oxygen on formation of low vibrational levels

0468847 - ÚFP 2017 RIV US eng A - Abstrakt
Šimek, Milan - Ambrico, P. F. - Prukner, Václav
N2(A) vibrational kinetics in streamer discharges: effect of oxygen on formation of low vibrational levels.
Bulletin of the American Physical Society. Vol. 61. Bochum: American Physical Society, 2016. s. 83. ISSN 0003-0503.
[APS Gaseous Electronics Conference 2016/69./. 10.10.2016-14.10.2016, Bochum]
Grant CEP: GA ČR(CZ) GA15-04023S
Institucionální podpora: RVO:61389021
Klíčová slova: dielectric barriere discharge * ozone generation
Kód oboru RIV: BL - Fyzika plazmatu a výboje v plynech

In the present study we report on the N2(A) vibrational kinetics in nitrogen-oxygen mixtures revealed by LIF technique under DBD streamer discharge conditions at low pressures. In pure nitrogen, the observed evolution of the N2(A) LIF signal during the decaying streamer channel period evidences fast initial relaxation of high vibrational levels towards the v = 2 and 3 levels, followed by a delayed increase of terminal v = 0 and 1 levels. In nitrogen-oxygen mixtures however, the efficient quenching of higher N2(A) levels by oxygen significantly inhibits vibrational relaxation towards the lower and terminal levels, causing much lower populations of the v = 0-3 levels. This is already clearly visible in the N2 + 0.8% O2 mixture with all the kinetics limited to the first 10 microseconds. In synthetic air, the kinetics is limited to few microseconds in the post discharge. Furthermore, much more effective quenching of fluorescence makes the measurements extremely challenging. Obtained results show that with the addition of oxygen the evolution of the N2(A) vibrational distribution is effectively terminated during the collisional-radiative cascade inhibiting energy pooling mechanism which is effective in pure nitrogen
Trvalý link: http://hdl.handle.net/11104/0266676