Indexed by:期刊论文

Date of Publication:2021-01-10

Journal:PLASMA PROCESSES AND POLYMERS

Volume:17

Issue:12

ISSN No.:1612-8850

Key Words:hydroxyl radicals; laser-induced fluorescence; pulse modulation; surface microdischarge

Abstract:Laser-induced fluorescence was used to determine the absolute OH density in a pulse-modulated atmospheric-pressure surface microdischarge in helium. Measurements were carried out during the discharge and post-discharge in both plasma layer and downstream region. Experimental findings show that dissipated power, modulation on-time duration, and the distance from the dielectric surface have more significant effects on the OH(X) lifetime than OH(X) density. The lifetime dependence on power is more pronounced as compared with the modulation duration. Moreover, a dielectric barrier discharge model was presented to estimate the density evolution and loss mechanisms of OH radicals. The results indicate that the decay of OH density is mainly due to the transport process and recombination reactions.