Complexity reduction effects on transient, atomic plasmas

Abrantes, Richard J. E.; Karagozian, A. R.; Bilyeu, D.; Le, H. P.

doi:10.1016/j.jqsrt.2018.05.013

Title: Complexity reduction effects on transient, atomic plasmas

Abstract

Plasma simulations involving collisional-radiative processes present many computational challenges because of the wide range in scales spanned by the governing set of plasma physics equations. These numerical challenges are primarily caused by limitations in resources such as memory and computational time. Collisional-radiative models deliver a part of the challenge because of the large number of levels and transitions that are associated with atomic plasmas. Multiple complexity reduction techniques have been introduced in the past to overcome this obstacle, including the quasi-steady-state solution, uniform grouping, and the recently-devised Boltzmann grouping. These reduction schemes were tested against full numerical simulations of a simplified, time-dependent argon model, with and without an external Planckian radiation field. Lastly, results will show the advantages and disadvantages of using complexity reduction techniques when employed in various plasma regimes.

Authors:

Abrantes, Richard J. E. ^[1];

^[2]; Bilyeu, D. ^[3]; Le, H. P. ^[4]

ERC Inc., Edwards AFB, CA (United States); Univ. of California, Los Angeles, CA (United States)
Univ. of California, Los Angeles, CA (United States)
Air Force Research Lab., Edwards AFB, CA (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Publication Date:: Fri May 18 00:00:00 EDT 2018

Research Org.:: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1466911

Alternate Identifier(s):: OSTI ID: 1776090

Report Number(s):: LLNL-JRNL-751721
Journal ID: ISSN 0022-4073; 937472

Grant/Contract Number:: AC52-07NA27344

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Quantitative Spectroscopy and Radiative Transfer

Additional Journal Information:: Journal Volume: 216; Journal Issue: C; Journal ID: ISSN 0022-4073

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Collisional-radiative models; Non-LTE plasmas

Citation Formats


                    Abrantes, Richard J. E., Karagozian, A. R., Bilyeu, D., and Le, H. P. Complexity reduction effects on transient, atomic plasmas.  United States: N. p., 2018. 
Web.  doi:10.1016/j.jqsrt.2018.05.013.

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                    Abrantes, Richard J. E., Karagozian, A. R., Bilyeu, D., & Le, H. P. Complexity reduction effects on transient, atomic plasmas.  United States.  https://doi.org/10.1016/j.jqsrt.2018.05.013

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                    Abrantes, Richard J. E., Karagozian, A. R., Bilyeu, D., and Le, H. P. Fri .  
"Complexity reduction effects on transient, atomic plasmas".  United States.  https://doi.org/10.1016/j.jqsrt.2018.05.013.  https://www.osti.gov/servlets/purl/1466911.

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@article{osti_1466911,

  title        = {Complexity reduction effects on transient, atomic plasmas},

  author       = {Abrantes, Richard J. E. and Karagozian, A. R. and Bilyeu, D. and Le, H. P.},

  abstractNote = {Plasma simulations involving collisional-radiative processes present many computational challenges because of the wide range in scales spanned by the governing set of plasma physics equations. These numerical challenges are primarily caused by limitations in resources such as memory and computational time. Collisional-radiative models deliver a part of the challenge because of the large number of levels and transitions that are associated with atomic plasmas. Multiple complexity reduction techniques have been introduced in the past to overcome this obstacle, including the quasi-steady-state solution, uniform grouping, and the recently-devised Boltzmann grouping. These reduction schemes were tested against full numerical simulations of a simplified, time-dependent argon model, with and without an external Planckian radiation field. Lastly, results will show the advantages and disadvantages of using complexity reduction techniques when employed in various plasma regimes.},

  doi          = {10.1016/j.jqsrt.2018.05.013},

  journal      = {Journal of Quantitative Spectroscopy and Radiative Transfer},

  number       = C,

  volume       = 216,

  place        = {United States},

  year         = {Fri May 18 00:00:00 EDT 2018},

  month        = {Fri May 18 00:00:00 EDT 2018}

}

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https://doi.org/10.1016/j.jqsrt.2018.05.013

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Cited by: 5 works

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Figures / Tables:

Figure 1: steady state charge fractions for each argon atomic charge for multiple electron temperatures with $N$_$e$ = 10¹⁹ cm⁻³. Comparisons were made against steady state FLYCHK results which includes dielectronic recombination.

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