An analysis of molten-corium-induced failure of drain pipes in BWR Mark 2 containments

Conference · Tue Jan 01 04:00:00 EST 1991

OSTI ID:5681831

Taleyarkhan, R P ^[1]; Podowski, M Z ^[2]

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1. Oak Ridge National Lab., TN (USA)
2. Rensselaer Polytechnic Inst., Troy, NY (USA)

This study has focused on mechanistic simulation and analysis of potential failure modes for inpedestal drywell drain pipes in the Limerick boiling water reactor (BWR) Mark 2 containment. Physical phenomena related to surface tension breakdown, heatup, melting, ablation, crust formation and failure, and core material relocation into drain pipes with simultaneous melting of pipe walls were modeled and analyzed. The results of analysis have been used to assess the possibility of drain pipe failure and the resultant loss of pressure-suppression capability. Estimates have been made for the timing and amount of molten corium released to the wetwell. The study has revealed that significantly different melt progression sequences can result depending upon the failure characteristics of the frozen metallic crust which forms over the drain cover during the initial stages of debris pour. Another important result is that it can take several days for the molten fuel to ablate the frozen metallic debris layer -- if the frozen layer has cooled below 1100 K before fuel attack. 10 refs., 3 figs., 4 tabs.

• Research Organization: Oak Ridge National Lab., TN (USA)
• Sponsoring Organization: DOE; NRC; USDOE, Washington, DC (USA); Nuclear Regulatory Commission, Washington, DC (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5681831
• Report Number(s): CONF-910739-13; ON: DE91011365
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210100 -- Power Reactors
Nonbreeding
Light-Water Moderated
Boiling Water Cooled
22 GENERAL STUDIES OF NUCLEAR REACTORS
220900* -- Nuclear Reactor Technology-- Reactor Safety
36 MATERIALS SCIENCE
360105 -- Metals & Alloys-- Corrosion & Erosion
99 GENERAL AND MISCELLANEOUS
990200 -- Mathematics & Computers
ABLATION
ACCIDENTS
ALLOYS
B CODES
BWR TYPE REACTORS
COMPUTER CODES
COMPUTERIZED SIMULATION
CONTAINERS
CORIUM
ELEMENTS
ENERGY TRANSFER
FAILURE MODE ANALYSIS
FLUID MECHANICS
HEAT TRANSFER
HYDRAULICS
IRON ALLOYS
IRON BASE ALLOYS
LIMERICK-2 REACTOR
MECHANICS
MELTDOWN
METALS
MOLTEN METAL-WATER REACTIONS
PIPES
POWER REACTORS
PRESSURE VESSELS
REACTOR ACCIDENTS
REACTOR CORE DISRUPTION
REACTOR SAFETY
REACTOR SAFETY EXPERIMENTS
REACTORS
SAFETY
SIMULATION
STEELS
SYSTEM FAILURE ANALYSIS
SYSTEMS ANALYSIS
TRANSITION ELEMENTS
WATER COOLED REACTORS
WATER MODERATED REACTORS
ZIRCONIUM