Macroscopic model of streamer

A three-dimensional fluid model of a streamer is described, which is based on the assumption that the charge carriers are in local thermal equilibrium so that the discharge may be described by a set of continuity equations together with the Poisson equation and with appropriate boundary conditions. Calculations are carried out for a rotationally symmetric, 5 mm wide, air-filled parallel-plate gap at atmospheric pressure. The model predicts both longitudinal and lateral motions of electron and ion swarms and thus accounts properly for such effects as radial diffusion and focusing. (J.U.) 3 figs., 6 refs