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Title: DIF3D nodal neutronics option for two- and three-dimensional diffusion theory calculations in hexagonal geometry. [LMFBR]

Abstract

A nodal method is developed for the solution of the neutron-diffusion equation in two- and three-dimensional hexagonal geometries. The nodal scheme has been incorporated as an option in the finite-difference diffusion-theory code DIF3D, and is intended for use in the analysis of current LMFBR designs. The nodal equations are derived using higher-order polynomial approximations to the spatial dependence of the flux within the hexagonal-z node. The final equations, which are cast in the form of inhomogeneous response-matrix equations for each energy group, involved spatial moments of the node-interior flux distribution plus surface-averaged partial currents across the faces of the node. These equations are solved using a conventional fission-source iteration accelerated by coarse-mesh rebalance and asymptotic source extrapolation. This report describes the mathematical development and numerical solution of the nodal equations, as well as the use of the nodal option and details concerning its programming structure. This latter information is intended to supplement the information provided in the separate documentation of the DIF3D code.

Authors:
Publication Date:
Research Org.:
Argonne National Lab., IL (USA)
OSTI Identifier:
6318594
Report Number(s):
ANL-83-1
ON: DE83011019
DOE Contract Number:
W-31-109-ENG-38
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; COMPUTER CODES; D CODES; LMFBR TYPE REACTORS; REACTOR CORES; REACTOR KINETICS; NEUTRON FLUX; REACTIVITY COEFFICIENTS; FUEL ASSEMBLIES; NEUTRON DIFFUSION EQUATION; THREE-DIMENSIONAL CALCULATIONS; TWO-DIMENSIONAL CALCULATIONS; BREEDER REACTORS; DIFFERENTIAL EQUATIONS; EPITHERMAL REACTORS; EQUATIONS; FAST REACTORS; FBR TYPE REACTORS; KINETICS; LIQUID METAL COOLED REACTORS; RADIATION FLUX; REACTOR COMPONENTS; REACTORS; 210500* - Power Reactors, Breeding

Citation Formats

Lawrence, R.D. DIF3D nodal neutronics option for two- and three-dimensional diffusion theory calculations in hexagonal geometry. [LMFBR]. United States: N. p., 1983. Web. doi:10.2172/6318594.
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Lawrence, R.D. DIF3D nodal neutronics option for two- and three-dimensional diffusion theory calculations in hexagonal geometry. [LMFBR]. United States. doi:10.2172/6318594.
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Lawrence, R.D. Tue . "DIF3D nodal neutronics option for two- and three-dimensional diffusion theory calculations in hexagonal geometry. [LMFBR]". United States. doi:10.2172/6318594. https://www.osti.gov/servlets/purl/6318594.
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@article{osti_6318594,
title = {DIF3D nodal neutronics option for two- and three-dimensional diffusion theory calculations in hexagonal geometry. [LMFBR]},
author = {Lawrence, R.D.},
abstractNote = {A nodal method is developed for the solution of the neutron-diffusion equation in two- and three-dimensional hexagonal geometries. The nodal scheme has been incorporated as an option in the finite-difference diffusion-theory code DIF3D, and is intended for use in the analysis of current LMFBR designs. The nodal equations are derived using higher-order polynomial approximations to the spatial dependence of the flux within the hexagonal-z node. The final equations, which are cast in the form of inhomogeneous response-matrix equations for each energy group, involved spatial moments of the node-interior flux distribution plus surface-averaged partial currents across the faces of the node. These equations are solved using a conventional fission-source iteration accelerated by coarse-mesh rebalance and asymptotic source extrapolation. This report describes the mathematical development and numerical solution of the nodal equations, as well as the use of the nodal option and details concerning its programming structure. This latter information is intended to supplement the information provided in the separate documentation of the DIF3D code.},
doi = {10.2172/6318594},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Mar 01 00:00:00 EST 1983},
month = {Tue Mar 01 00:00:00 EST 1983}
}
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Technical Report:
View Technical Report (2.46 MB)
DOI:  10.2172/6318594
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