Reduced entropic model for studies of multidimensional nonlocal transport in highenergydensity plasmas
Abstract
Hydrodynamic simulations of highenergydensity 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 FokkerPlanck equation. This multidimensional model is closed thanks to an entropic relation (the Boltzman Htheorem). 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 ionacoustic waves, driven by the heat flux, are presented and compared with the classical formula.
 Authors:
 Centre Lasers Intenses et Applications, Université de BordeauxCNRSCEA, UMR 5107, F33405 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; FOKKERPLANCK EQUATION; H THEOREM; HEAT FLUX; ION ACOUSTIC WAVES; PLASMA; PLASMA INSTABILITY; SIMULATION
Citation Formats
Del Sorbo, D., Feugeas, J.L., Nicolaï, Ph., OlazabalLoumé, M., Dubroca, B., Guisset, S., Touati, M., and Tikhonchuk, V.. Reduced entropic model for studies of multidimensional nonlocal transport in highenergydensity plasmas. United States: N. p., 2015.
Web. doi:10.1063/1.4926824.
Del Sorbo, D., Feugeas, J.L., Nicolaï, Ph., OlazabalLoumé, M., Dubroca, B., Guisset, S., Touati, M., & Tikhonchuk, V.. Reduced entropic model for studies of multidimensional nonlocal transport in highenergydensity plasmas. United States. doi:10.1063/1.4926824.
Del Sorbo, D., Feugeas, J.L., Nicolaï, Ph., OlazabalLoumé, M., Dubroca, B., Guisset, S., Touati, M., and Tikhonchuk, V.. 2015.
"Reduced entropic model for studies of multidimensional nonlocal transport in highenergydensity plasmas". United States.
doi:10.1063/1.4926824.
@article{osti_22490067,
title = {Reduced entropic model for studies of multidimensional nonlocal transport in highenergydensity plasmas},
author = {Del Sorbo, D. and Feugeas, J.L. and Nicolaï, Ph. and OlazabalLoumé, M. and Dubroca, B. and Guisset, S. and Touati, M. and Tikhonchuk, V.},
abstractNote = {Hydrodynamic simulations of highenergydensity 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 FokkerPlanck equation. This multidimensional model is closed thanks to an entropic relation (the Boltzman Htheorem). 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 ionacoustic 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 = 2015,
month = 8
}

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