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arXiv · 2009.09707

Shear flow in a three-dimensional complex plasma in microgravity conditions

V. Nosenko·M. Pustylnik·M. Rubin-Zuzic·A. M. Lipaev·A. V. Zobnin·A. D. Usachev·H. M. Thomas·M. H. Thoma·V. E. Fortov·O. Kononenko·A. Ovchinin
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Abstract

Shear flow in a three-dimensional complex plasma was experimentally studied in microgravity conditions using Plasmakristall-4 (PK-4) instrument on board the International Space Station (ISS). The shear flow was created in an extended suspension of microparticles by applying the radiation pressure force of the manipulation-laser beam. Individual particle trajectories in the flow were analyzed and from these, using the Navier-Stokes equation, an upper estimate of the complex plasma's kinematic viscosity was calculated in the range of $0.2$--$6.7~{\rm mm^2/s}$. This estimate is much lower than previously reported in ground-based experiments with 3D complex plasmas. Possible reasons of this difference are discussed.

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V. Nosenko, M. Pustylnik, M. Rubin-Zuzic, A. M. Lipaev, A. V. Zobnin, A. D. Usachev, H. M. Thomas, M. H. Thoma, V. E. Fortov, O. Kononenko, A. Ovchinin. 2020-09-21. Shear flow in a three-dimensional complex plasma in microgravity conditions. https://doi.org/10.1103/physrevresearch.2.033404

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