Autowaves in a dc complex plasma confined behind a de Laval nozzle
1 Max-Planck-Institute for Extraterrestrial Physics - Giessenbachstr., 85748 Garching, Germany, EU
2 Department of Chemical and Biomolecular Engineering, University of California - Berkeley, CA 94720, USA
Received: 21 March 2013
Accepted: 6 May 2013
Experiments to explore stability conditions and topology of a dense microparticle cloud supported against gravity by a gas flow were carried out. By using a nozzle-shaped glass insert within the glass tube of a dc discharge plasma chamber a weakly ionized gas flow through a de Laval nozzle was produced. The experiments were performed using neon gas at a pressure of 100 Pa and melamine-formaldehyde particles with a diameter of 3.43 μm. The capturing and stable global confining of the particles behind the nozzle in the plasma were demonstrated. The particles inside the cloud behaved as a single convection cell inhomogeneously structured along the nozzle axis in a tube-like manner. The pulsed acceleration localized in the very head of the cloud mediated by collective plasma-particle interactions and the resulting wave pattern were studied in detail.
PACS: 52.27.Lw – Dusty or complex plasmas; plasma crystals / 52.30.-q – Plasma dynamics and flow
© EPLA, 2013