Hybrid S{sub N} numerical method free from spatial truncation error for slab lattice calculations

Barros, R C

Title: Hybrid S{sub N} numerical method free from spatial truncation error for slab lattice calculations

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Abstract

In typical lattice cells where a highly absorbing, small fuel element is embedded in the moderator (a large weakly absorbing medium), high-order transport methods become unnecessary. In this paper we describe a hybrid discrete ordinates (S{sub N}) nodal method for slab lattice calculations. This hybrid S{sub N} method combines the convenience of a low-order S{sub N} method in the moderator with a high-order S{sub N} method in the fuel. The idea is based on the fact that in weakly absorbing media whose physical size is several neutron mean free paths in extent, even the S{sub 2} method (P{sub 1} approximation), leads to an accurate result. We use special fuel-moderator interface conditions and the spectral Green`s function (SGF) numerical nodal method completely free from spatial truncation error, to calculate the neutron flux distribution and the disadvantage factor.

Authors:: Barros, R C

Publication Date:: Sat Dec 31 00:00:00 EST 1994

OSTI Identifier:: 89137

Report Number(s):: CONF-941102-
Journal ID: TANSAO; ISSN 0003-018X; TRN: 95:004215-0209

Resource Type:: Journal Article

Journal Name:: Transactions of the American Nuclear Society

Additional Journal Information:: Journal Volume: 71; Conference: Winter meeting of the American Nuclear Society (ANS), Washington, DC (United States), 13-18 Nov 1994; Other Information: PBD: 1994

Country of Publication:: United States

Language:: English

Subject:: 66 PHYSICS; 22 NUCLEAR REACTOR TECHNOLOGY; REACTOR LATTICES; NEUTRON TRANSPORT; NODAL EXPANSION METHOD; DISCRETE ORDINATE METHOD; GREEN FUNCTION; REACTOR PHYSICS

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                    Barros, R C. Hybrid S{sub N} numerical method free from spatial truncation error for slab lattice calculations.  United States: N. p., 1994. 
        Web.

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                    Barros, R C. Hybrid S{sub N} numerical method free from spatial truncation error for slab lattice calculations.  United States.

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                    Barros, R C. 1994.  
        "Hybrid S{sub N} numerical method free from spatial truncation error for slab lattice calculations".  United States.

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@article{osti_89137,

  title        = {Hybrid S{sub N} numerical method free from spatial truncation error for slab lattice calculations},

  author       = {Barros, R C},

  abstractNote = {In typical lattice cells where a highly absorbing, small fuel element is embedded in the moderator (a large weakly absorbing medium), high-order transport methods become unnecessary. In this paper we describe a hybrid discrete ordinates (S{sub N}) nodal method for slab lattice calculations. This hybrid S{sub N} method combines the convenience of a low-order S{sub N} method in the moderator with a high-order S{sub N} method in the fuel. The idea is based on the fact that in weakly absorbing media whose physical size is several neutron mean free paths in extent, even the S{sub 2} method (P{sub 1} approximation), leads to an accurate result. We use special fuel-moderator interface conditions and the spectral Green`s function (SGF) numerical nodal method completely free from spatial truncation error, to calculate the neutron flux distribution and the disadvantage factor.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/89137},
  journal      = {Transactions of the American Nuclear Society},
number       = ,

  volume       = 71,

  place        = {United States},

  year         = {Sat Dec 31 00:00:00 EST 1994},

  month        = {Sat Dec 31 00:00:00 EST 1994}

}

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