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Title: Three-dimensional two-fluid Braginskii simulations of the large plasma device

The Large Plasma Device (LAPD) is modeled using the 3D Global Braginskii Solver code. Comparisons to experimental measurements are made in the low-bias regime in which there is an intrinsic E × B rotation of the plasma. In the simulations, this rotation is caused primarily by sheath effects and may be a likely mechanism for the intrinsic rotation seen in LAPD. Simulations show strong qualitative agreement with the data, particularly the radial dependence of the density fluctuations, cross-correlation lengths, radial flux dependence outside of the cathode edge, and camera imagery. Kelvin Helmholtz (KH) turbulence at relatively large scales is the dominant driver of cross-field transport in these simulations with smaller-scale drift waves and sheath modes playing a secondary role. Plasma holes and blobs arising from KH vortices in the simulations are consistent with the scale sizes and overall appearance of those in LAPD camera images. The addition of ion-neutral collisions in the simulations at previously theorized values reduces the radial particle flux by about a factor of two, from values that are somewhat larger than the experimentally measured flux to values that are somewhat lower than the measurements. This reduction is due to a modest stabilizing contribution of the collisions on themore » KH-modes driving the turbulent transport.« less
Authors:
;  [1] ; ; ;  [2]
  1. Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)
  2. Department of Physics and Astronomy, University of California, Los Angeles, California 90095-1547 (United States)
Publication Date:
OSTI Identifier:
22490140
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 9; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CATHODES; DENSITY; ELECTRIC FIELDS; FLUCTUATIONS; HELMHOLTZ INSTABILITY; IMAGES; ION-ATOM COLLISIONS; MAGNETIC FIELDS; PLASMA SIMULATION; ROTATING PLASMA; THERMONUCLEAR DEVICES; THREE-DIMENSIONAL CALCULATIONS; TURBULENCE; VORTICES; WAVE PROPAGATION