Gas mixing enhanced by power modulations in atmospheric pressure microwave plasma jet. (29th February 2016)

• Record Type: Journal Article
• Authors: Voráč, J; Potočňáková, L; Synek, P; Hnilica, J; Kudrle, V
• Is Part Of: Plasma sources science & technology. Volume 25:Number 2(2016:Apr.)
• Publication Date: 2016-02-29
• Subjects: microwave plasma -- atmospheric pressure -- plasma jet -- gas mixing -- vortex; Plasma (Ionized gases) -- Periodicals; 530.44
• DOI: 10.1088/0963-0252/25/2/025018
• Languages: English
• ISSNs: 0963-0252

Abstract

Abstract: Microwave plasma jet operating in atmospheric pressure argon was power modulated by audio frequency sine envelope in the 10 2 W power range. Its effluent was imaged using interference filters and ICCD camera for several different phases of the modulating signal. The combination of this fast imaging with spatially resolved optical emission spectroscopy provides useful insights into the plasmachemical processes involved. Phase-resolved schlieren photography was performed to visualize the gas dynamics. The results show that for higher modulation frequencies the plasma chemistry is strongly influenced by formation of transient flow perturbation resembling a vortex during each period. The perturbation formation and speed are strongly influenced by the frequency and power variations while they depend only weakly on the working gas flow rate. From application point of view, the perturbation presence significantly broadened lateral distribution of active species, effectively increasing cross-sectional area suitable for applications.