Transport of charge carriers applications can often result in models with a very high cell Péclet number — that is, systems where drift or convection dominates over diffusion. Numerical stabilization techniques are of paramount importance to obtain physically reasonable results. The Electric Discharge Interface provides both Streamline Diffusion stabilization and Isotropic Diffusion stabilization. See more details in Numerical Stabilization in the COMSOL Multiphysics Reference Manual.

In the Electric Discharge interface, a built-in global variable, edis.minDRT, represents the minimal dielectric relaxation time. This variable corresponds to the smallest charge relaxation time among all dielectric domains, calculated as ε/σ. For an example of its usage, refer to the model Positive Streamer Propagation in Transformer Oil in the Electric Discharge Module Application Library.