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Experimental Methods of Dust Charging and Mobilization on Surfaces with Exposure to Ultraviolet Radiation or Plasmas
Published on: April 3, 2018
Convective dust clouds driven by thermal creep in a complex plasma
S Mitic1, R Sütterlin, A V Ivlev H Höfner
1Max-Planck-Institut für extraterrestrische Physik, D-85741 Garching, Germany.
Physical Review Letters
|December 31, 2008
Summary
Microparticle clouds levitate in glow discharge due to gas convection. Thermal creep along heated tube walls drives this convection, crucial for understanding complex plasma experiments.
Area of Science:
- Physics
- Plasma Physics
- Fluid Dynamics
Background:
- Microparticles levitate in glow discharge.
- Global convective motion observed in particle clouds.
- Vertical confinement above a heated ring.
Purpose of the Study:
- Investigate the cause of particle vortices in levitating microparticle clouds.
- Identify the mechanism driving neutral gas convection.
- Determine the role of thermal creep in complex plasma experiments.
Main Methods:
- Observation of steady-state microparticle clouds in a glow discharge.
- Utilizing a heated ring for particle confinement and establishing thermal gradients.
- Analysis of neutral gas convection and its effect on microparticle motion.
Main Results:
- Particle vortices were induced by neutral gas convection.
- Thermal creep along inhomogeneously heated tube walls was identified as the cause of gas convection.
- Demonstrated the significant role of thermal creep in rarefied gas phenomena.
Conclusions:
- Neutral gas convection, driven by thermal creep, induces particle vortices in glow discharge plasmas.
- Thermal creep is a key phenomenon in rarefied gases with thermal gradients.
- This mechanism is important for experiments involving complex plasmas and levitating microparticles.
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