Non-local electron kinetic fluid models for numerical investigation of streamers in nitrogen

We present the results of a second order fluid model in which the mean electron energy, ε, is used as the parameter for ionization rate ν_I(ε), and the reduced electric filed, E/N, is used as a parameter for mobility and diffusion coefficient . We have previously shown that the local mean electron energy is not a suitable parameter for mobility/drift and diffusion of electrons due to big difference in momentum relaxation and energy relaxation time¹. The proposed second order fluid model in 3-dimesions assuming azimuthal symmetry was used to investigate streamers in N₂ at atmospheric pressures. We will discuss the difference between the proposed model and the other standard first and second order models, and particle-in-cell (PIC) used for the streamer simulations. The characterization presented will include the streamer propagation speed, density, and the radial dimensions. The results of the proposed model are in very good agreement with PIC simulations. We will also present the results of excited species estimation in streamer discharges using the proposed model.

1. Dhali S. K., Plasma Sources Sci. Technol. Vol 31, 025014 (2022).