Scaled-up Nonequilibrium Air Plasmas
نویسندگان
چکیده
The volume scalability of nonequilibrium plasmas produced by electrical discharges in atmospheric pressure air has been investigated. A variety of direct current (DC) and pulsed glow discharges obtained in either slow flow of ambient or fast flow of preheated (~2000 K) air at atmospheric pressure is presented. Single DC and repetitively pulsed discharges represent the first approach. Stable discharges with electron number densities as high as 10 cm were obtained without filamentation. A large decrease of the input power by 2-3 orders of magnitude was achieved in pulsed discharges, in comparison with the DC discharges. A dual-discharge facility was developed that combines two parallel DC discharges in either ambient or preheated air. Uniform plasma volumes of a few cubic centimeters have been achieved by this technique. Multiple pulsed discharges in parallel have been examined as well in order to increase the plasma volume. Finally, some paradoxical results on DC discharges in transverse gas flow are presented. The temperature distribution effecting the reduced electric field E/N is found to strongly influence the shape of the discharge. * Postdoctoral Fellow, Member AIAA † Senior Research Scientist, Associate Fellow AIAA, currently Professor, Ecole Centrale Paris, France ‡ Postdoctoral Fellow, currently Professor, University Paris-Nord, France § Graduate Research Assistant, Student Member AIAA, currently Postdoctoral Fellow, ONERA, France ** Postdoctoral Fellow †† Professor, Vice Provost, Dean of Research and Graduate Policy, Member AIAA
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