Title :
Initiation mechanism of negative pulsed discharge in supercritical carbon dioxide
Author :
Furusato, Tomohiro ; Ihara, T. ; Kiyan, T. ; Katsuki, S. ; Hara, Masaki ; Akiyama, Hidenori
Author_Institution :
Grad. Sch. of Sci. & Technol., Kumamoto Univ., Kumamoto, Japan
Abstract :
The initiation mechanism of a negative pulsed discharge in pressurized carbon dioxide including supercritical (SC) phase was studied using pulsed Schlieren and photomultiplier techniques. The appearance of the negative streamer at its initial stage was quite different from the positive one: a bush of negative polarity and a filament of positive polarity. A clear discontinuity existed around the sub-critical phase, characterized by streamer initiation voltage versus medium condition: The streamer initiation voltage increased with the medium density in gas phase, but was mostly independent of the medium density in SC and liquid phases. Calculation of field emission current according to Fowler-Nordheim equation suggested that the streamer initiation in both SC and liquid phases was caused by field emission, while within gas phase, initial electrons might be supplied by electron detachment from CO2- ions.
Keywords :
carbon compounds; discharges (electric); electron detachment; field emission; photomultipliers; pulsed power technology; Fowler-Nordheim equation; SC; electron detachment; field emission current; gas phase; liquid phase; negative polarity; negative pulsed discharge initiation mechanism; negative streamer; photomultiplier technique; positive polarity; pressurized carbon dioxide; pulsed Schlieren technique; supercritical carbon dioxide; Field emission; Negative pulsed streamer; Schlieren method; Supercritical carbon dioxide;
Conference_Titel :
Power Modulator and High Voltage Conference (IPMHVC), 2012 IEEE International
Conference_Location :
San Diego, CA
Print_ISBN :
978-1-4673-1222-6
DOI :
10.1109/IPMHVC.2012.6518676