Comparison of dust charging between orbital-motion-limited theory and particle-in-cell simulations

Journal Article · Sun Nov 15 00:00:00 EST 2015 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.4935697· OSTI ID:22489889

Tang, Xian-Zhu ^[1]

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1. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

The Orbital-Motion-Limited (OML) theory has been modified to predict the dust charge and the results were contrasted with the Whipple approximation [X. Z. Tang and G. L. Delzanno, Phys. Plasmas 21, 123708 (2014)]. To further establish its regime of applicability, in this paper, the OML predictions (for a non-electron-emitting, spherical dust grain at rest in a collisionless, unmagnetized plasma) are compared with particle-in-cell simulations that retain the absorption radius effect. It is found that for large dust grain radius r{sub d} relative to the plasma Debye length λ{sub D}, the revised OML theory remains a very good approximation as, for the parameters considered (r{sub d}/λ{sub D} ≤ 10, equal electron and ion temperatures), it yields the dust charge to within 20% accuracy. This is a substantial improvement over the Whipple approximation. The dust collected currents and energy fluxes, which remain the same in the revised and standard OML theories, are accurate to within 15%–30%.

• OSTI ID: 22489889
• Journal Information: Physics of Plasmas, Vol. 22, Issue 11; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ABSORPTION
ACCURACY
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
DEBYE LENGTH
DUSTS
PLASMA
SPHERICAL CONFIGURATION