Modeling of negative streamer propagation in a weak uniform electric field

The results of numerical simulations of negative streamers in air at atmospheric pressure in a weak and uniform electric field are presented. Streamer development was considered between a protrusion on a plane cathode and a plane anode separated by a distance of 3.3 cm. The region with an enhanced field near the protrusion tip, where streamer inception took place, was ~0.3 cm long and the propagation region with a uniform background field covered ~3 cm of the gap length. The parameters of the streamers were studied for different magnitudes of the background field strength: 5, 6, 7 and 8 kV/cm at constant magnitude of the field strength at the tip of the protrusion aiming to determine minimal field required for stable propagation. Internal and integral characteristics of streamers developing in different background fields are discussed and analyzed. 1