A study of dust grain screening in a weakly ionized plasma based on the numerical solution of the Vlasov-Bhatnagar-Gross-Krook kinetic equations

Journal Article · Sat Oct 15 00:00:00 EDT 2011 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3646918· OSTI ID:22047009

Semenov, I L; Krivtsun, I V ^[1]; Zagorodny, A G ^[2]

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1. E. O. Paton Electric Welding Institute, 11 Bozhenko str., Kiev 03680 (Ukraine)
2. Bogolyubov Institute for Theoretical Physics, 14B Metrolohichna str., Kiev 03680 (Ukraine)

Screening of a dust grain in a weakly ionized plasma is studied for a wide range of collisional regimes. The problem is considered on the basis of the Vlasov-Bhatnagar-Gross-Krook equations for plasma particles. The equations are solved numerically on parallel processors by means of a high-order finite-volume method. The computations are carried out for different pressures of plasma background and different grain sizes. The values of the total grain charge, distributions of the electric potential, and basic macroscopic parameters of plasma particles (concentration, temperature, and velocity) are obtained. For two limiting cases of the collisionless and strongly collisional background, the obtained results are found to be in good agreement with those computed using the commonly known models (nonlinear collisionless models of Bystrenko et al.[Phys. Lett. A 299, 383 (2002)] and Ratynskaia et al.[Phys. Plasmas 13, 104508 (2006)] and drift-diffusion approach). For the transitional collisional regime, it is shown that the electric potential also has the Coulomb-type asymptotical behavior related to the presence of charging currents and existence of some residual (unscreened) grain charge. Both total and residual grain charges are found to increase as the collisional regime tends to the continuum limit. In addition, the influence of collisions on the ion distribution function near the grain surface is demonstrated.

• OSTI ID: 22047009
• Journal Information: Physics of Plasmas, Vol. 18, Issue 10; Other Information: (c) 2011 American Institute of Physics; 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
BOLTZMANN-VLASOV EQUATION
CHARGE DISTRIBUTION
COLLISIONS
DIFFUSION
DISTRIBUTION FUNCTIONS
DUSTS
ELECTRIC POTENTIAL
ELECTRON TEMPERATURE
GRAIN SIZE
ION TEMPERATURE
IONIZATION
IONS
KINETIC EQUATIONS
NUMERICAL SOLUTION
PARTICLES
PLASMA
PLASMA PRESSURE
POTENTIAL ENERGY