Fukushima Daiichi Unit 1 ex-vessel prediction: Core melt spreading

Journal Article · Mon Oct 31 00:00:00 EDT 2016 · Nuclear Technology

DOI:https://doi.org/10.13182/NT16-44· OSTI ID:1350684

Farmer, M. T. ^[1]; Robb, K. R. ^[2]; Francis, M. W. ^[2]

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1. Argonne National Lab. (ANL), Argonne, IL (United States)
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Lower head failure and corium-concrete interaction were predicted to occur at Fukushima Daiichi Unit 1 (1F1) by several different system-level code analyses, including MELCOR v2.1 and MAAP5. Although these codes capture a wide range of accident phenomena, they do not contain detailed models for ex-vessel core melt behavior. However, specialized codes exist for analysis of ex-vessel melt spreading (e.g., MELTSPREAD) and long-term debris coolability (e.g., CORQUENCH). On this basis, an analysis has been carried out to further evaluate ex-vessel behavior for 1F1 using MELTSPREAD and CORQUENCH. Best-estimate melt pour conditions predicted by MELCOR v2.1 and MAAP5 were used as input. MELTSPREAD was then used to predict the spatially-dependent melt conditions and extent of spreading during relocation from the vessel. Lastly, this information was then used as input for the long-term debris coolability analysis with CORQUENCH that is reported in a companion paper.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1350684
• Alternate ID(s): OSTI ID: 1351269
• Journal Information: Nuclear Technology, Journal Name: Nuclear Technology Journal Issue: 3 Vol. 196; ISSN 0029-5450
• Publisher: American Nuclear Society (ANS)
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
Fukushima
ex-vessel
severe accident
spreading