Non-newtonian viscosity of complex-plasma fluids.
A V Ivlev1, V Steinberg, R Kompaneets
1Max-Planck-Institut für extraterrestrische Physik, 85748 Garching, Germany. ivlev@mpe.mpg.de
Physical Review Letters
|May 16, 2007
Summary
This study investigated shear flows in complex plasma fluids. Results show complex plasmas exhibit non-Newtonian behavior and shear thinning, especially at high shear rates.
Area of Science:
- Plasma Physics
- Fluid Dynamics
- Materials Science
Background:
- Complex plasmas, often generated in DC discharges, are unique states of matter with unique fluid properties.
- Understanding the rheological behavior of these plasmas is crucial for applications and fundamental science.
Purpose of the Study:
- To investigate shear flows in three-dimensional complex plasma fluids.
- To measure the viscosity of complex plasmas across a wide range of shear rates.
- To identify non-Newtonian characteristics in complex plasma behavior.
Main Methods:
- Inducing shear flow using inhomogeneous gas flow or laser beams.
- Measuring plasma viscosity under varying shear rates, approaching the hydrodynamic limit.
- Analyzing fluid behavior at different scales, including where particle discreteness is significant.
Main Results:
- Complex plasmas exhibit significant non-Newtonian fluid behavior.
- Shear thinning was observed, indicating a decrease in viscosity with increasing shear rate.
- Viscosity measurements extended to the hydrodynamic limit, revealing behavior influenced by particle discreteness.
Conclusions:
- Complex plasmas display non-Newtonian characteristics, specifically shear thinning.
- The study provides valuable data on complex plasma rheology, particularly near the hydrodynamic limit.
- Findings contribute to a deeper understanding of fluid dynamics in complex plasma systems.
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