OECD MCCI Small-Scale Water Ingression and Crust Strength tests (SSWICS) design report, Rev. 2 October 31, 2002.

Farmer, M. ; Lomperski, S. ; Kilsdonk, D. ; Aeschlimann, B. ; Pfeiffer, P. (Nuclear Engineering Division) ; (NRC)

关键词: ANL;    CORIUM;    DESIGN;    FRACTURE PROPERTIES;    FRACTURES;    FREEZING;    GASES;    HEAT TRANSFER;    HEATING;    OECD;    QUENCHING;    SAFETY REPORTS;    TEMPERATURE GRADIENTS;    THERMAL STRESSES;    WATER;   

DOI  :  10.2172/1014860
RP-ID  :  OECD/MCCI-2002-TR01
PID  :  OSTI ID: 1014860
Others  :  TRN: US1102889

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来源: SciTech Connect

【 摘 要 】

The Melt Attack and Coolability Experiments (MACE) program at Argonne National Laboratory addressed the issue of the ability of water to cool and thermally stabilize a molten core/concrete interaction (MCCI) when the reactants are flooded from above. These tests provided data regarding the nature of corium interactions with concrete, the heat transfer rates from the melt to the overlying water pool, and the role of noncondensable gases in the mixing processes that contribute to melt quenching. However, due to the integral nature of these tests, several questions regarding the crust freezing behavior could not be adequately resolved. These questions include: (1) To what extent does water ingression into the crust increase the melt quench rate above the conduction-limited rate and how is this affected by melt composition and system pressure and (2) What is the fracture strength of the corium crust when subjected to a thermal-mechanical load and how does it depend upon the melt composition? A series of separate-effects experiments are planned to address these issues. The first employs an apparatus designed to measure the quench rate of a pool of corium ({approx}{phi}30 cm; up to 20 cm deep). The main parameter to be varied in these quench tests is the melt composition since it is thought to have a critical influence on the crust cracking behavior which, in turn, alters quench rate. A description of the test apparatus, instrumentation, data reduction, and test matrix are the subject of the first portion of this report. The issue of crust strength will be addressed with a second apparatus designed to mechanically load the crust produced by the quench tests. This apparatus will measure the fracture strength of the crust while under a thermal load created by a heating element beneath the crust. The introduction of a thermal gradient across the crust is thought to be important for these tests because of uncertainty in the magnitude of the thermal stresses and thus their relative importance in the crust fracture mechanism at plant scale. The second half of this report describes the apparatus for measuring crust strength. The two apparatuses used to measure the melt quench rate and crust strength are jointly referred to as SSWICS (Small-Scale Water Ingression and Crust Strength).