Drift-diffusion plasma fluid models are commonly used to simulate electric discharges. Such models can computationally be very efficient if they are combined with explicit time integration. This paper deals with two issues that often arise with such models. First, a high plasma conductivity can severely limit the time step. A fully explicit method to overcome this limitation is presented. This method is compared to the existing semi-implicit method, and it is shown to have several advantages. A second issue is specific to models with the local field approximation. Near strong density and electric field gradients, electrons can diffuse parallel to the field, and unphysically generate ionization. Existing and new approaches to correct this behavior are compared. Details on the implementation of the models and the various approaches are provided.

dielectric relaxation time, drift-diffusion, explicit time integration, fluid model, parallel diffusion
dx.doi.org/10.1088/1361-6595/ab6757
Plasma Sources Science and Technology
Centrum Wiskunde & Informatica, Amsterdam, The Netherlands

Teunissen, H.J. (2020). Improvements for drift-diffusion plasma fluid models with explicit time integration. Plasma Sources Science and Technology, 29(1). doi:10.1088/1361-6595/ab6757