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Author Fisher, Dustin M. ♦ Rogers, Barrett N. ♦ Rossi, Giovanni D. ♦ Guice, Daniel S. ♦ Carter, Troy A.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword 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
Abstract 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 the KH-modes driving the turbulent transport.
ISSN 1070664X
Educational Use Research
Learning Resource Type Article
Publisher Date 2015-09-15
Publisher Place United States
Journal Physics of Plasmas
Volume Number 22
Issue Number 9


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