Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30528
Improvement of Model for SIMMER Code for SFR Corium Relocation Studies

Authors: A. Bachrata, N. Marie, F. Bertrand, J. B. Droin

Abstract:

The in-depth understanding of severe accident propagation in Generation IV of nuclear reactors is important so that appropriate risk management can be undertaken early in their design process. This paper is focused on model improvements in the SIMMER code in order to perform studies of severe accident mitigation of Sodium Fast Reactor. During the design process of the mitigation devices dedicated to extraction of molten fuel from the core region, the molten fuel propagation from the core up to the core catcher has to be studied. In this aim, analytical as well as the complex thermohydraulic simulations with SIMMER-III code are performed. The studies presented in this paper focus on physical phenomena and associated physical models that influence the corium relocation. Firstly, the molten pool heat exchange with surrounding structures is analyzed since it influences directly the instant of rupture of the dedicated tubes favoring the corium relocation for mitigation purpose. After the corium penetration into mitigation tubes, the fuel-coolant interactions result in formation of debris bed. Analyses of debris bed fluidization as well as sinking into a fluid are presented in this paper.

Keywords: corium, mitigation tubes, SIMMER-III, sodium fast reactor (SFR)

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1091460

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2492

References:


[1] Sa Kondo et al., Phase 2 Code Assessment of SIMMER-III, JNC TN9400, 2000, 105.
[2] L. Godin-Jacqmin, Application de SIMMER sur les résultats expérimentaux GEYSER: utilization d’une loi de viscosité multi-fluide améliorée, CEA internal report, 2012.
[3] P. Coste, Calculation of the Large Scale UO2/Sodium Interactions of the TERMOS T1 Experiment with the SIMMER-III Code, CEA Internal Report, 1998.
[4] K. Morita et al., SIMMER-III Applications to Fuel-Coolant Interactions, Nuclear Engineering and Design 189 (1999), 337-357.
[5] J. Toyooka et al., SIMMER-III Analysis of EAGLE-1 In-Pile Tests Focusing on Heat Transfer from Molten Core Material to Steel-Wall Structure, JAEA, in press.
[6] R. Meignen, Calculations of the SCARABEE BF2 Experiment with SIMMER-III, SMTH/LM2/98-10, CEA internal report, 1998.
[7] D. J. Brear, Revisions to SIMMER-III to Simulate Free-Convection Heat Transfer from Boiling Pools, JAEA report DJB/02, 1995.
[8] D. Alvarez, P. Malterre, J. M. Seiler, Natural Convection in Volume Heated Liquid Pools- the BAFOND Experiments: Proposal for New Correlations, Science and Technology of Fast Reactor Safety, BNES, London, 1986.