Comparison of multifluid moment models with particleincell simulations of collisionless magnetic reconnection
Abstract
We introduce an extensible multifluid moment model in the context of collisionless magnetic reconnection. This model evolves full Maxwell equations and simultaneously moments of the VlasovMaxwell equation for each species in the plasma. Effects like electron inertia and pressure gradient are selfconsistently embedded in the resulting multifluid moment equations, without the need to explicitly solving a generalized Ohm's law. Two limits of the multifluid moment model are discussed, namely, the fivemoment limit that evolves a scalar pressures for each species and the tenmoment limit that evolves the full anisotropic, nongyrotropic pressure tensor for each species. We first demonstrate analytically and numerically that the fivemoment model reduces to the widely used Hall magnetohydrodynamics (Hall MHD) model under the assumptions of vanishing electron inertia, infinite speed of light, and quasineutrality. Then, we compare tenmoment and fully kinetic particleincell (PIC) simulations of a large scale Harris sheet reconnection problem, where the tenmoment equations are closed with a local linear collisionless approximation for the heat flux. The tenmoment simulation gives reasonable agreement with the PIC results regarding the structures and magnitudes of the electron flows, the polarities and magnitudes of elements of the electron pressure tensor, and the decomposition of the generalized Ohm's law.more »
 Authors:
 Space Science Center and Physics Department, University of New Hampshire, Durham, New Hampshire 03824 (United States)
 Center for Heliophysics, Princeton Plasma Physics Laboratory, Princeton, New Jersey 085430451 (United States)
 Publication Date:
 OSTI Identifier:
 22407986
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 1; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ANISOTROPY; BOLTZMANNVLASOV EQUATION; CLOSURES; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; ELECTRONS; FLUIDS; HALL EFFECT; HEAT FLUX; MAGNETIC RECONNECTION; MAGNETOHYDRODYNAMICS; MAXWELL EQUATIONS; MOMENT OF INERTIA; MOMENTS METHOD; PLASMA; PLASMA SHEET; PRESSURE GRADIENTS; SCALARS; THREEDIMENSIONAL CALCULATIONS; VISIBLE RADIATION
Citation Formats
Wang, Liang, Email: liang.wang@unh.edu, Germaschewski, K., Hakim, Ammar H., and Bhattacharjee, A.. Comparison of multifluid moment models with particleincell simulations of collisionless magnetic reconnection. United States: N. p., 2015.
Web. doi:10.1063/1.4906063.
Wang, Liang, Email: liang.wang@unh.edu, Germaschewski, K., Hakim, Ammar H., & Bhattacharjee, A.. Comparison of multifluid moment models with particleincell simulations of collisionless magnetic reconnection. United States. doi:10.1063/1.4906063.
Wang, Liang, Email: liang.wang@unh.edu, Germaschewski, K., Hakim, Ammar H., and Bhattacharjee, A.. 2015.
"Comparison of multifluid moment models with particleincell simulations of collisionless magnetic reconnection". United States.
doi:10.1063/1.4906063.
@article{osti_22407986,
title = {Comparison of multifluid moment models with particleincell simulations of collisionless magnetic reconnection},
author = {Wang, Liang, Email: liang.wang@unh.edu and Germaschewski, K. and Hakim, Ammar H. and Bhattacharjee, A.},
abstractNote = {We introduce an extensible multifluid moment model in the context of collisionless magnetic reconnection. This model evolves full Maxwell equations and simultaneously moments of the VlasovMaxwell equation for each species in the plasma. Effects like electron inertia and pressure gradient are selfconsistently embedded in the resulting multifluid moment equations, without the need to explicitly solving a generalized Ohm's law. Two limits of the multifluid moment model are discussed, namely, the fivemoment limit that evolves a scalar pressures for each species and the tenmoment limit that evolves the full anisotropic, nongyrotropic pressure tensor for each species. We first demonstrate analytically and numerically that the fivemoment model reduces to the widely used Hall magnetohydrodynamics (Hall MHD) model under the assumptions of vanishing electron inertia, infinite speed of light, and quasineutrality. Then, we compare tenmoment and fully kinetic particleincell (PIC) simulations of a large scale Harris sheet reconnection problem, where the tenmoment equations are closed with a local linear collisionless approximation for the heat flux. The tenmoment simulation gives reasonable agreement with the PIC results regarding the structures and magnitudes of the electron flows, the polarities and magnitudes of elements of the electron pressure tensor, and the decomposition of the generalized Ohm's law. Possible ways to improve the simple local closure towards a nonlocal fully threedimensional closure are also discussed.},
doi = {10.1063/1.4906063},
journal = {Physics of Plasmas},
number = 1,
volume = 22,
place = {United States},
year = 2015,
month = 1
}

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