[13p-1F-3~18] 8.0 Plasma Electronics English Session

[13p-1F-15] Liquid flow induced by atmospheric-pressure dc glow discharge in contact with liquid

〇Fumiyoshi Tochikubo¹, Takuya Aoki¹, Naoki Shirai¹, Satoshi Uchida¹ (1.Tokyo Metro. Univ.)

Keywords:atmospheric pressure plasma,liquid flow characteristics

Atmospheric-pressure discharges in contact with liquid are widely applied to water treatment and material processing. In these applications, primary reactions between radicals and liquid molecules always occur at plasma-liquid interface. Since the diffusion in the liquid is very slow, the depletion of chemicals at liquid surface causes the rate-limiting. Therefore, some convective flow is necessary to exchange the chemicals at the plasma-liquid interface for the promotion of efficient reactions. In our previous work, we found the appearance of downward flow in the liquid just below the dc glow discharge in contact with liquid. This downward flow will be effective for exchanging the chemicals at plasma-liquid interface.
In this work, we investigated the characteristics of liquid flow induced by atmospheric-pressure dc glow discharge with liquid electrode. The spatiotemporal evolution of liquid flow was visualized by schlieren method, and the temperature distribution was measured using temperature-sensitive liquid crystal particles dispersed in the liquid. We confirmed the appearance of specific downflow in the liquid just below the discharge. The liquid-flow characteristics was reproduced by a fluid simulation considering a downward driving force at liquid surface from plasma. The candidate of the driving force will be the momentum transfer of charged species from plasma at the liquid surface.