Neutronics Investigations for the Lower Part of a Westinghouse SVEA-96+ Assembly

Journal Article · Wed May 15 04:00:00 EDT 2002 · Nuclear Science and Engineering

OSTI ID:20804775

Murphy, M F ^[1]; Luethi, A ^[1]; Seiler, R ^[1]; Grimm, P ^[1]; Joneja, O ^[1]; Meister, A ^[1]; Geemert, R van ^[1]; Jatuff, F ^[1]; Brogli, R ^[1]; Jacot-Guillarmod, R ^[2]; Williams, T ^[2]; Helmersson, S ^[3]; Chawla, R ^[1]

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1. Paul Scherrer Institute (Switzerland)
2. Elektrizitats-Gesellschaft Laufenburg AG (Switzerland)
3. Westinghouse Atom AB (Sweden)

Accurate critical experiments have been performed for the validation of total fission (F{sub tot}) and {sup 238}U-capture (C{sub 8}) reaction rate distributions obtained with CASMO-4, HELIOS, BOXER, and MCNP4B for the lower axial region of a real Westinghouse SVEA-96+ fuel assembly. The assembly comprised fresh fuel with an average {sup 235}U enrichment of 4.02 wt%, a maximum enrichment of 4.74 wt%, 14 burnable-absorber fuel pins, and full-density water moderation. The experimental configuration investigated was core 1A of the LWR-PROTEUS Phase I project, where 61 different fuel pins, representing {approx}64% of the assembly, were gamma-scanned individually. Calculated (C) and measured (E) values have been compared in terms of C/E distributions. For F{sub tot}, the standard deviations are 1.2% for HELIOS, 0.9% for CASMO-4, 0.8% for MCNP4B, and 1.7% for BOXER. Standard deviations of 1.1% for HELIOS, CASMO-4, and MCNP4B and 1.2% for BOXER were obtained in the case of C{sub 8}. Despite the high degree of accuracy observed on the average, it was found that the five burnable-absorber fuel pins investigated showed a noticeable underprediction of F{sub tot}, quite systematically, for the deterministic codes evaluated (average C/E for the burnable-absorber fuel pins in the range 0.974 to 0.988, depending on the code)

• OSTI ID: 20804775
• Journal Information: Nuclear Science and Engineering, Journal Name: Nuclear Science and Engineering Journal Issue: 1 Vol. 141; ISSN NSENAO; ISSN 0029-5639
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
DENSITY
DISTRIBUTION
ENRICHMENT
FISSION
FUEL ASSEMBLIES
FUEL PINS
NUCLEAR FUELS
URANIUM 235
URANIUM 238