Fluid theory of magnetized plasma dynamics at low collisionality
Abstract
Finite Larmor radius (FLR) fluid equations for magnetized plasmas evolving on either sonic or diamagnetic drift time scales are derived consistent with a broad lowcollisionality hypothesis. The fundamental expansion parameter is the ratio {delta} between the ion Larmor radius and the shortest macroscopic length scale (including fluctuation wavelengths in the absence of small scale turbulence). The lowcollisionality regime of interest is specified by assuming that the other two basic small parametersnamely, the ratio between the electron and ion masses and the ratio between the ion collision and cyclotron frequenciesare comparable to or smaller than {delta}{sup 2}. First significant order FLR equations for the stress tensors and the heat fluxes are given, including a detailed discussion of the collisional terms that need be retained under the assumed orderings and of the closure terms that need be determined kinetically. This analysis is valid for any magnetic geometry and for fully electromagnetic nonlinear dynamics with arbitrarily large fluctuation amplitudes. It is also valid for strong anisotropies and does not require the distribution functions to be close to Maxwellians. With a subsidiary smallparallelgradient ordering for largeaspectratio toroidal plasmas in a strong but weakly inhomogeneous magnetic field, a new system of reduced twofluid equations ismore »
 Authors:
 Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
 Publication Date:
 OSTI Identifier:
 20974987
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 5; Other Information: DOI: 10.1063/1.2717595; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ASPECT RATIO; CYCLOTRON FREQUENCY; DISTRIBUTION FUNCTIONS; ELECTRON TEMPERATURE; ELECTRONS; FLUCTUATIONS; HEAT FLUX; ION COLLISIONS; ION TEMPERATURE; IONS; LARMOR RADIUS; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; NONLINEAR PROBLEMS; PLASMA; PLASMA DENSITY; PLASMA DIAMAGNETISM; PLASMA FLUID EQUATIONS
Citation Formats
Ramos, J. J. Fluid theory of magnetized plasma dynamics at low collisionality. United States: N. p., 2007.
Web. doi:10.1063/1.2717595.
Ramos, J. J. Fluid theory of magnetized plasma dynamics at low collisionality. United States. doi:10.1063/1.2717595.
Ramos, J. J. Tue .
"Fluid theory of magnetized plasma dynamics at low collisionality". United States.
doi:10.1063/1.2717595.
@article{osti_20974987,
title = {Fluid theory of magnetized plasma dynamics at low collisionality},
author = {Ramos, J. J.},
abstractNote = {Finite Larmor radius (FLR) fluid equations for magnetized plasmas evolving on either sonic or diamagnetic drift time scales are derived consistent with a broad lowcollisionality hypothesis. The fundamental expansion parameter is the ratio {delta} between the ion Larmor radius and the shortest macroscopic length scale (including fluctuation wavelengths in the absence of small scale turbulence). The lowcollisionality regime of interest is specified by assuming that the other two basic small parametersnamely, the ratio between the electron and ion masses and the ratio between the ion collision and cyclotron frequenciesare comparable to or smaller than {delta}{sup 2}. First significant order FLR equations for the stress tensors and the heat fluxes are given, including a detailed discussion of the collisional terms that need be retained under the assumed orderings and of the closure terms that need be determined kinetically. This analysis is valid for any magnetic geometry and for fully electromagnetic nonlinear dynamics with arbitrarily large fluctuation amplitudes. It is also valid for strong anisotropies and does not require the distribution functions to be close to Maxwellians. With a subsidiary smallparallelgradient ordering for largeaspectratio toroidal plasmas in a strong but weakly inhomogeneous magnetic field, a new system of reduced twofluid equations is derived, rigorously taking into account all the diamagnetic effects associated with arbitrary density and anisotropic temperature gradients.},
doi = {10.1063/1.2717595},
journal = {Physics of Plasmas},
number = 5,
volume = 14,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}

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