The Bohm criterion and boundary conditions for a multicomponent system

Journal Article · Tue Aug 01 04:00:00 EDT 1995 · IEEE Transactions on Plasma Science

DOI:https://doi.org/10.1109/27.467993· OSTI ID:118918

Riemann, K U ^[1]

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1. Ruhr-Univ., Bochum (Germany). Institut fuer Theoretische Physik

In the asymptotic limit {lambda}{sub D} {yields} 0 (small Debye length) the boundary layer problem of a plasma is split up into the separate problems of a quasineutral presheath and a collision free planar sheath. The formation of a stationary sheath requires that the ions fulfill a sheath condition (``Bohm criterion``). In this paper, the boundary layer problem of a multicomponent system is investigated. Both in the frames of a hydrodynamic and of a kinetic theory, a generalized sheath condition is derived accounting for various ion components and arbitrary electron and ion distributions. It is shown that the sheath condition is usually fulfilled marginally (in the equality form) and provides a boundary condition for the plasma analysis.

• OSTI ID: 118918
• Journal Information: IEEE Transactions on Plasma Science, Journal Name: IEEE Transactions on Plasma Science Journal Issue: 4 Vol. 23; ISSN ITPSBD; ISSN 0093-3813
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
BOHM CRITERION
BOUNDARY CONDITIONS
PLASMA SHEATH
PLASMA SIMULATION
SPACE CHARGE