Stretched and Filtered Multigroup Pn Transport for Improved Positivity and Accuracy

Olson, Gordon L.

doi:10.1080/23324309.2020.1800745

Title: Stretched and Filtered Multigroup Pn Transport for Improved Positivity and Accuracy

Abstract

One of the common methods for solving the radiation transport equation is to use a polynomial expansion for the angle variable(s). Recent research that reduces the oscillations and improves the positivity of the gray transport equation solutions is here applied to the multigroup transport equations. Constant scale factors that stretch the time axis and constant scattering opacities that filter the solution greatly increase the accuracy of the solution with no added nonlinearities. No new solution techniques are required. Test problems are presented in one and two dimensions.

Authors:

Olson, Gordon L. ^[1]

Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Publication Date:: Tue Aug 11 00:00:00 EDT 2020

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

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

OSTI Identifier:: 1735898

Report Number(s):: LA-UR-20-21822
Journal ID: ISSN 2332-4309; TRN: US2205262

Grant/Contract Number:: 89233218CNA000001

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Computational and Theoretical Transport

Additional Journal Information:: Journal Volume: 49; Journal Issue: 5; Journal ID: ISSN 2332-4309

Publisher:: Taylor and Francis

Country of Publication:: United States

Language:: English

Subject:: 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; radiation transport; Pn transport; positivity; stretched and filtered Pn

Citation Formats


                    Olson, Gordon L. Stretched and Filtered Multigroup Pn Transport for Improved Positivity and Accuracy.  United States: N. p., 2020. 
Web.  doi:10.1080/23324309.2020.1800745.

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                    Olson, Gordon L. Stretched and Filtered Multigroup Pn Transport for Improved Positivity and Accuracy.  United States.  https://doi.org/10.1080/23324309.2020.1800745

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                    Olson, Gordon L. Tue .  
"Stretched and Filtered Multigroup Pn Transport for Improved Positivity and Accuracy".  United States.  https://doi.org/10.1080/23324309.2020.1800745.  https://www.osti.gov/servlets/purl/1735898.

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@article{osti_1735898,

  title        = {Stretched and Filtered Multigroup Pn Transport for Improved Positivity and Accuracy},

  author       = {Olson, Gordon L.},

  abstractNote = {One of the common methods for solving the radiation transport equation is to use a polynomial expansion for the angle variable(s). Recent research that reduces the oscillations and improves the positivity of the gray transport equation solutions is here applied to the multigroup transport equations. Constant scale factors that stretch the time axis and constant scattering opacities that filter the solution greatly increase the accuracy of the solution with no added nonlinearities. No new solution techniques are required. Test problems are presented in one and two dimensions.},

  doi          = {10.1080/23324309.2020.1800745},

  journal      = {Journal of Computational and Theoretical Transport},

  number       = 5,

  volume       = 49,

  place        = {United States},

  year         = {Tue Aug 11 00:00:00 EDT 2020},

  month        = {Tue Aug 11 00:00:00 EDT 2020}

}

Copy to clipboard

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Works referenced in this record:

Robust and accurate filtered spherical harmonics expansions for radiative transfer
journal, August 2010

McClarren, Ryan G.; Hauck, Cory D.
Journal of Computational Physics, Vol. 229, Issue 16
DOI: 10.1016/j.jcp.2010.03.043

Positivity enhancements to the P _n transport equations
journal, July 2019

Olson, Gordon L.
Journal of Computational and Theoretical Transport, Vol. 48, Issue 5
DOI: 10.1080/23324309.2019.1669661

Temporal accuracy of the nonequilibrium radiation diffusion equations employing a Saha ionization model
journal, November 2005

Rauenzahn, R. M.; Mousseau, V. A.; Knoll, D. A.
Computer Physics Communications, Vol. 172, Issue 2
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Alternate closures for radiation transport using Legendre polynomials in 1D and spherical harmonics in 2D
journal, April 2012

Olson, Gordon L.
Journal of Computational Physics, Vol. 231, Issue 7
DOI: 10.1016/j.jcp.2011.12.013

Second order time evolution of the multigroup diffusion and P1 equations for radiation transport
journal, August 2011

Olson, Gordon L.
Journal of Computational Physics, Vol. 230, Issue 20
DOI: 10.1016/j.jcp.2011.06.001

Second-order time evolution of PN equations for radiation transport
journal, May 2009

Olson, Gordon L.
Journal of Computational Physics, Vol. 228, Issue 8
DOI: 10.1016/j.jcp.2009.01.012

Diffusion, P1, and other approximate forms of radiation transport
journal, March 2000

Olson, Gordon L.; Auer, Lawrence H.; Hall, Michael L.
Journal of Quantitative Spectroscopy and Radiative Transfer, Vol. 64, Issue 6
DOI: 10.1016/S0022-4073(99)00150-8

Diffusive Corrections to $P_N$ Approximations
journal, January 2011

Schäfer, Matthias; Frank, Martin; Levermore, C. David
Multiscale Modeling & Simulation, Vol. 9, Issue 1
DOI: 10.1137/090764542

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Title: Stretched and Filtered Multigroup Pn Transport for Improved Positivity and Accuracy

Abstract

Citation Formats

Robust and accurate filtered spherical harmonics expansions for radiative transfer journal, August 2010

Positivity enhancements to the P n transport equations journal, July 2019

Temporal accuracy of the nonequilibrium radiation diffusion equations employing a Saha ionization model journal, November 2005

Alternate closures for radiation transport using Legendre polynomials in 1D and spherical harmonics in 2D journal, April 2012

Second order time evolution of the multigroup diffusion and P1 equations for radiation transport journal, August 2011

Second-order time evolution of PN equations for radiation transport journal, May 2009

Diffusion, P1, and other approximate forms of radiation transport journal, March 2000

Diffusive Corrections to $P_N$ Approximations journal, January 2011

Robust and accurate filtered spherical harmonics expansions for radiative transfer
journal, August 2010

Positivity enhancements to the P _n transport equations
journal, July 2019

Temporal accuracy of the nonequilibrium radiation diffusion equations employing a Saha ionization model
journal, November 2005

Alternate closures for radiation transport using Legendre polynomials in 1D and spherical harmonics in 2D
journal, April 2012

Second order time evolution of the multigroup diffusion and P1 equations for radiation transport
journal, August 2011

Second-order time evolution of PN equations for radiation transport
journal, May 2009

Diffusion, P1, and other approximate forms of radiation transport
journal, March 2000

Diffusive Corrections to $P_N$ Approximations
journal, January 2011