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Title: Reduced entropic model for studies of multidimensional nonlocal transport in high-energy-density plasmas

Abstract

Hydrodynamic simulations of high-energy-density plasmas require a detailed description of energy fluxes. For low and intermediate atomic number materials, the leading mechanism is the electron transport, which may be a nonlocal phenomenon requiring a kinetic modeling. In this paper, we present and test the results of a nonlocal model based on the first angular moments of a simplified Fokker-Planck equation. This multidimensional model is closed thanks to an entropic relation (the Boltzman H-theorem). It provides a better description of the electron distribution function, thus enabling studies of small scale kinetic effects within the hydrodynamic framework. Examples of instabilities of electron plasma and ion-acoustic waves, driven by the heat flux, are presented and compared with the classical formula.

Authors:
; ; ; ; ; ; ;  [1]
  1. Centre Lasers Intenses et Applications, Université de Bordeaux-CNRS-CEA, UMR 5107, F-33405 Talence (France)
Publication Date:
OSTI Identifier:
22490067
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 8; 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; ATOMIC NUMBER; DISTRIBUTION FUNCTIONS; ELECTRON TRANSFER; ELECTRONS; ENERGY DENSITY; FOKKER-PLANCK EQUATION; H THEOREM; HEAT FLUX; ION ACOUSTIC WAVES; PLASMA; PLASMA INSTABILITY; SIMULATION

Citation Formats

Del Sorbo, D., Feugeas, J.-L., Nicolaï, Ph., Olazabal-Loumé, M., Dubroca, B., Guisset, S., Touati, M., and Tikhonchuk, V.. Reduced entropic model for studies of multidimensional nonlocal transport in high-energy-density plasmas. United States: N. p., 2015. Web. doi:10.1063/1.4926824.
Del Sorbo, D., Feugeas, J.-L., Nicolaï, Ph., Olazabal-Loumé, M., Dubroca, B., Guisset, S., Touati, M., & Tikhonchuk, V.. Reduced entropic model for studies of multidimensional nonlocal transport in high-energy-density plasmas. United States. doi:10.1063/1.4926824.
Del Sorbo, D., Feugeas, J.-L., Nicolaï, Ph., Olazabal-Loumé, M., Dubroca, B., Guisset, S., Touati, M., and Tikhonchuk, V.. Sat . "Reduced entropic model for studies of multidimensional nonlocal transport in high-energy-density plasmas". United States. doi:10.1063/1.4926824.
@article{osti_22490067,
title = {Reduced entropic model for studies of multidimensional nonlocal transport in high-energy-density plasmas},
author = {Del Sorbo, D. and Feugeas, J.-L. and Nicolaï, Ph. and Olazabal-Loumé, M. and Dubroca, B. and Guisset, S. and Touati, M. and Tikhonchuk, V.},
abstractNote = {Hydrodynamic simulations of high-energy-density plasmas require a detailed description of energy fluxes. For low and intermediate atomic number materials, the leading mechanism is the electron transport, which may be a nonlocal phenomenon requiring a kinetic modeling. In this paper, we present and test the results of a nonlocal model based on the first angular moments of a simplified Fokker-Planck equation. This multidimensional model is closed thanks to an entropic relation (the Boltzman H-theorem). It provides a better description of the electron distribution function, thus enabling studies of small scale kinetic effects within the hydrodynamic framework. Examples of instabilities of electron plasma and ion-acoustic waves, driven by the heat flux, are presented and compared with the classical formula.},
doi = {10.1063/1.4926824},
journal = {Physics of Plasmas},
number = 8,
volume = 22,
place = {United States},
year = {Sat Aug 15 00:00:00 EDT 2015},
month = {Sat Aug 15 00:00:00 EDT 2015}
}
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