A new approach to core-reflector boundary conditions for nodal reactor computations

Journal Article · Fri Apr 01 04:00:00 EST 1994 · Nuclear Science and Engineering; (United States)

OSTI ID:7110784

Joo, H K; Kim, C H ^[1]; Noh, J M; Kim, S H ^[2]

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1. Seoul National Univ. (Korea, Republic of). Dept. of Nuclear Engineering
2. Korea Atomic Energy Research Institute, Taejeon (Korea, Republic of)

New core-reflector boundary conditions designed to replace the explicit representation of the reflector in nodal computations are developed taking into account the transverse leakage in the reflector region. Two approximations are introduced for the transverse leakage in the reflector region: exponential approximation for the slab reflector and quadratic polynomial and exponential approximation for the L-shaped reflector. Core-reflector boundary conditions that relate net current with flux at the core-reflector interfaces are then derived by solving the transverse integrated neutron diffusion equation with transverse leakage approximations in the reflector region. To test the usefulness of new core-reflector boundary conditions, nodal expansion method computations with and without explicit representation of reflectors are performed for the core power distribution and criticality of Zion-1 and YGN-1 pressurized water reactors. It is demonstrated that core power and criticality computations with new boundary conditions agree very well with those with the reflector included explicitly in computational nodes.

• OSTI ID: 7110784
• Journal Information: Nuclear Science and Engineering; (United States), Journal Name: Nuclear Science and Engineering; (United States) Vol. 116:4; ISSN NSENAO; ISSN 0029-5639
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210200* -- Power Reactors
Nonbreeding
Light-Water Moderated
Nonboiling Water Cooled
CALCULATION METHODS
CRITICALITY
ENRICHED URANIUM REACTORS
MATHEMATICAL MODELS
NEUTRON LEAKAGE
NEUTRON REFLECTORS
NODAL EXPANSION METHOD
POWER DISTRIBUTION
POWER REACTORS
PWR TYPE REACTORS
REACTOR COMPONENTS
REACTOR CORES
REACTORS
THERMAL REACTORS
WATER COOLED REACTORS
WATER MODERATED REACTORS
ZION-1 REACTOR