A 2D/1D transverse leakage approximation based on azimuthal, Fourier moments
Abstract
Here, the MPACT code being developed collaboratively by Oak Ridge National Laboratory and the University of Michigan is the primary deterministic neutron transport solver within the Virtual Environment for Reactor Applications Core Simulator (VERACS). In MPACT, the twodimensional (2D)/onedimensional (1D) scheme is the most commonly used method for solving neutron transportbased threedimensional nuclear reactor core physics problems. Several axial solvers in this scheme assume isotropic transverse leakages, but work with the axial S _{N} solver has extended these leakages to include both polar and azimuthal dependence. However, explicit angular representation can be burdensome for runtime and memory requirements. The work here alleviates this burden by assuming that the azimuthal dependence of the angular flux and transverse leakages are represented by a Fourier series expansion. At the heart of this is a new axial SN solver that takes in a Fourier expanded radial transverse leakage and generates the angular fluxes used to construct the axial transverse leakages used in the 2DMethod of Characteristics calculations.
 Authors:
 Univ. of Michigan, Ann Arbor, MI (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Univ. of Michigan, Ann Arbor, MI (United States)
 Publication Date:
 Research Org.:
 Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1344985
 Grant/Contract Number:
 AC0500OR22725
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Nuclear Science and Engineering
 Additional Journal Information:
 Journal Volume: 185; Journal Issue: 2; Journal ID: ISSN 00295639
 Publisher:
 American Nuclear Society  Taylor & Francis
 Country of Publication:
 United States
 Language:
 English
 Subject:
 97 MATHEMATICS AND COMPUTING; 21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
Citation Formats
Stimpson, Shane G., Collins, Benjamin S., and Downar, Thomas. A 2D/1D transverse leakage approximation based on azimuthal, Fourier moments. United States: N. p., 2017.
Web. doi:10.1080/00295639.2016.1272360.
Stimpson, Shane G., Collins, Benjamin S., & Downar, Thomas. A 2D/1D transverse leakage approximation based on azimuthal, Fourier moments. United States. doi:10.1080/00295639.2016.1272360.
Stimpson, Shane G., Collins, Benjamin S., and Downar, Thomas. Thu .
"A 2D/1D transverse leakage approximation based on azimuthal, Fourier moments". United States.
doi:10.1080/00295639.2016.1272360. https://www.osti.gov/servlets/purl/1344985.
@article{osti_1344985,
title = {A 2D/1D transverse leakage approximation based on azimuthal, Fourier moments},
author = {Stimpson, Shane G. and Collins, Benjamin S. and Downar, Thomas},
abstractNote = {Here, the MPACT code being developed collaboratively by Oak Ridge National Laboratory and the University of Michigan is the primary deterministic neutron transport solver within the Virtual Environment for Reactor Applications Core Simulator (VERACS). In MPACT, the twodimensional (2D)/onedimensional (1D) scheme is the most commonly used method for solving neutron transportbased threedimensional nuclear reactor core physics problems. Several axial solvers in this scheme assume isotropic transverse leakages, but work with the axial SN solver has extended these leakages to include both polar and azimuthal dependence. However, explicit angular representation can be burdensome for runtime and memory requirements. The work here alleviates this burden by assuming that the azimuthal dependence of the angular flux and transverse leakages are represented by a Fourier series expansion. At the heart of this is a new axial SN solver that takes in a Fourier expanded radial transverse leakage and generates the angular fluxes used to construct the axial transverse leakages used in the 2DMethod of Characteristics calculations.},
doi = {10.1080/00295639.2016.1272360},
journal = {Nuclear Science and Engineering},
number = 2,
volume = 185,
place = {United States},
year = {Thu Jan 12 00:00:00 EST 2017},
month = {Thu Jan 12 00:00:00 EST 2017}
}
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