Viscosity calculated in simulations of strongly-coupled dusty plasmas with gas friction

Abstract

A two-dimensional strongly-coupled dusty plasma is modeled using Langevin and frictionless molecular dynamical simulations. The static viscosity $\hat{I}\cdot$ and the wave-number-dependent viscosity $\hat{I}\cdot (k)$ are calculated from the microscopic shear in the random motion of particles. A recently developed method of calculating the wave-number-dependent viscosity $\hat{I}\cdot (k)$ is validated by comparing the results of $\hat{I}\cdot (k)$ from the two simulations. It is also verified that the Green-Kubo relation can still yield an accurate measure of the static viscosity $\hat{I}\cdot$ in the presence of a modest level of friction as in dusty plasma experiments.

6 pages, 3 figures, Physics of Plasmas invited paper