Numerical method for multigroup one-dimensional S[sub N] eigenvalue problems with no spatial truncation error

Conference · Fri Jan 01 04:00:00 EST 1993 · Transactions of the American Nuclear Society; (United States)

OSTI ID:6836968

Abreu, M P; Filho, H A ^[1]; Barros, R C ^[2]

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1. COPPE/UFRJ-Nuclear, Rio de Janeiro (Brazil)
2. Instituto de Engenharia Nuclear, Rio de Janeiro (Brazil)

The authors describe a new nodal method for multigroup slab-geometry discrete ordinates S[sub N] eigenvalue problems that is completely free from all spatial truncation errors. The unknowns in the method are the node-edge angular fluxes, the node-average angular fluxes, and the effective multiplication factor k[sub eff]. The numerical values obtained for these quantities are exactly those of the dominant analytic solution of the S[sub N] eigenvalue problem apart from finite arithmetic considerations. This method is based on the use of the standard balance equation and two nonstandard auxiliary equations. In the nonmultiplying regions, e.g., the reflector, we use the multigroup spectral Green's function (SGF) auxiliary equations. In the fuel regions, we use the multigroup spectral diamond (SD) auxiliary equations. The SD auxiliary equation is an extension of the conventional auxiliary equation used in the diamond difference (DD) method. This hybrid characteristic of the SD-SGF method improves both the numerical stability and the convergence rate.

• OSTI ID: 6836968
• Report Number(s): CONF-931160--
• Conference Information: Journal Name: Transactions of the American Nuclear Society; (United States) Journal Volume: 69
• Country of Publication: United States
• Language: English

Related Subjects

663610* -- Neutron Physics-- (1992-)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CALCULATION METHODS
EIGENVALUES
ERRORS
MULTIGROUP THEORY
NEUTRAL-PARTICLE TRANSPORT
NEUTRON TRANSPORT
NEUTRON TRANSPORT THEORY
ONE-DIMENSIONAL CALCULATIONS
PHYSICS
RADIATION TRANSPORT
REACTOR PHYSICS
TRANSPORT THEORY