Long filamentary discharge produced in helium spiral vortex

We report the generation of long plasma filament confined in a helium spiral vortex at atmospheric pressure. The discharge is produced by a dielectric barrier discharge setup and confined in the center of a spiral vortex. The length of the discharge can be several centimeters with flow rate less than 1 SLM. We find that the long filamentary discharge is the trajectory of fast-traveling plasma bursts and plasma plumes, where the plasma bursts are similar to the plasma jet produced at atmospheric pressure. The speeds of the downstream and upstream plasma bursts are about 46 000 and 95 000 m/s, respectively, which are affected by the spirally upward helium gas flow. Based on the novel design of vortex-confined discharge, we show that a plasma filament with a length of 10 cm can be produced. Published under an exclusive license by AIP Publishing.

Automated summary

The study reports the generation of long plasma filaments confined in a helium spiral vortex at atmospheric pressure. The discharge is produced by a dielectric barrier discharge setup and confined in the center of a spiral vortex, with the length of the discharge reaching several centimeters.