Self-consistent, nonlocal electron heat flux at arbitrary ion charge number

Journal Article · Sun Nov 01 04:00:00 EST 1992 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860366· OSTI ID:7028101

Sanmartin, J R; Ramirez, J ^[1]; Fernandez-Feria, R ^[2]; Minotti, F ^[3]

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1. E.T.S.I. Aeronauticos, Universidad Politecnica, 28040 Madrid (Spain)
2. E.T.S.I. Industriales, Universidad de Sevilla, 41012 Sevilla (Spain)
3. Laboratorio de Fisica del Plasma, Universidad de Buenos Aires, 1428 Buenos Aires (Argentina)

A single, nonlocal expression for the electron heat flux, which closely reproduces known results at high and low ion charge number {ital Z}, and exact'' results for the local limit at all {ital Z}, is derived by solving the kinetic equation in a narrow, tail-energy range. The solution involves asymptotic expansions of Bessel functions of large argument, and ({ital Z}-dependent) order above or below it, corresponding to the possible parabolic or hyperbolic character of the kinetic equation; velocity space diffusion in self-scattering is treated similarly to isotropic thermalization of tail energies in large {ital Z} analyses. The scale length {ital H} characterizing nonlocal effects varies with {ital Z}, suggesting an equal dependence of any {ital ad} {ital hoc} flux limiter. The model is valid for all {ital H} above the mean-free path for {ital thermal} electrons.

• OSTI ID: 7028101
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 4:11; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700330* -- Plasma Kinetics
Transport
& Impurities-- (1992-)
ASYMPTOTIC SOLUTIONS
BESSEL FUNCTIONS
CHARGES
COLLISIONS
DISTRIBUTION FUNCTIONS
ELECTRON COLLISIONS
ELECTRON-ION COLLISIONS
EQUATIONS
FUNCTIONS
HEAT FLUX
ION COLLISIONS
KINETIC EQUATIONS
MEAN FREE PATH
TRANSPORT THEORY