Streamers in water filled wire-cylinder and packed-bed reactors

Streamers in a coaxial reactor filled with tap water have been investigated. Up to six primary plasma channels originated simultaneously from a common point at the center electrode, from where they branched out radially, driven by the electric field. Points of origin were distributed over the wire with an average separation of 5 mm. The streamers propagated at above 60 km/s velocity near the center electrode and slowed to about 30 km/s when they reached the middle of the gap. The streamers accelerated again as they approached the outer electrode. Packing the reactor with silica gel beads generated more homogeneous plasma.