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Title: Resolving Rapid Variation in Energy for Particle Transport

Abstract

Resolving the rapid variation in energy in neutron and thermal radiation transport is needed for the predictive simulation capability in high-energy density physics applications. Energy variation is difficult to resolve due to rapid variations in cross sections and opacities caused by quantized energy levels in the nuclei and electron clouds. In recent work, we have developed a new technique to simultaneously capture slow and rapid variations in the opacities and the solution using homogenization theory, which is similar to multiband (MB) and to the finite-element with discontiguous support (FEDS) method, but does not require closure information. We demonstrated the accuracy and efficiency of the method for a variety of problems. We are researching how to extend the method to problems with multiple materials and the same material but with different temperatures and densities. In this highlight, we briefly describe homogenization theory and some results.

Authors:
 [1];  [1];  [1];  [1];  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Computer, Computational, and Statistical Sciences Division
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1304798
Report Number(s):
LA-UR-16-26450
DOE Contract Number:
AC52-06NA25396
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; neutron transport; thermal radiation transfer; multigroup; multiband; homogenization

Citation Formats

Haut, Terry Scot, Ahrens, Cory Douglas, Jonko, Alexandra, Till, Andrew Thomas, and Lowrie, Robert Byron. Resolving Rapid Variation in Energy for Particle Transport. United States: N. p., 2016. Web. doi:10.2172/1304798.
Haut, Terry Scot, Ahrens, Cory Douglas, Jonko, Alexandra, Till, Andrew Thomas, & Lowrie, Robert Byron. Resolving Rapid Variation in Energy for Particle Transport. United States. doi:10.2172/1304798.
Haut, Terry Scot, Ahrens, Cory Douglas, Jonko, Alexandra, Till, Andrew Thomas, and Lowrie, Robert Byron. 2016. "Resolving Rapid Variation in Energy for Particle Transport". United States. doi:10.2172/1304798. https://www.osti.gov/servlets/purl/1304798.
@article{osti_1304798,
title = {Resolving Rapid Variation in Energy for Particle Transport},
author = {Haut, Terry Scot and Ahrens, Cory Douglas and Jonko, Alexandra and Till, Andrew Thomas and Lowrie, Robert Byron},
abstractNote = {Resolving the rapid variation in energy in neutron and thermal radiation transport is needed for the predictive simulation capability in high-energy density physics applications. Energy variation is difficult to resolve due to rapid variations in cross sections and opacities caused by quantized energy levels in the nuclei and electron clouds. In recent work, we have developed a new technique to simultaneously capture slow and rapid variations in the opacities and the solution using homogenization theory, which is similar to multiband (MB) and to the finite-element with discontiguous support (FEDS) method, but does not require closure information. We demonstrated the accuracy and efficiency of the method for a variety of problems. We are researching how to extend the method to problems with multiple materials and the same material but with different temperatures and densities. In this highlight, we briefly describe homogenization theory and some results.},
doi = {10.2172/1304798},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 8
}

Technical Report:

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