Numerical simulation of discharge behavior and network analysis of reaction chemistry in an atmospheric plasma jet*

Atmospheric pressure dielectric barrier discharge jets are one of the typical examples of low temperature plasma sources. The plasma is ignited by a pulsed discharge and passed through a guided helium jet. The luminous zone (plasma plume) extending into the open air consists of a series of streamers. In this research, we conduct numerical simulations with a two-dimensional axi-symmetrical model to investigate the ionizing wave propagation (streamer behavior) of a kHz-driven helium atmospheric pressure plasma jet. The two-dimensional plasma-fluid dynamics model consists of a steady fluid dynamics part, a plasma dynamics part and chemical kinetics. Numerically derived two-dimensional maps of the streamer propagation are compared with experimental results obtained using optical emission spectroscopy and high-speed imaging [1]. Furthermore, the complex network analysis based on graph-theory can reveal hidden feature of gas-phase chemistry by the visualization of the growth of the reacting network [2,3]. [1] C. McDonnell, et al. J. Plasma Phys. 88 (2022) 905880316. [2] T. Murakami and O. Sakai, Plasma Sources Sci. Technol. 29 (2020) 115018. [3] O. Sakai, S. Kawaguchi and T. Murakami, Jpn. J. Appl. Phys. 61 (2022) 070101.