Thermal-hydraulic impact of failure of highly irradiated fuel pins on LMR passive safety

Conference · Mon Jan 01 04:00:00 EST 1990 · Transactions of the American Nuclear Society; (USA)

OSTI ID:5822172

Dunn, F E; Herzog, J P

The Experimental Breeder Reactor II (EBR-II) SHRT-45 loss-of-primary-flow-without-scram test and SHRT 302 unprotected loss-of-heat-sink test have demonstrated that liquid-metal reactors can be built with a high degree of passive safety. No fuel pins failed in these tests; but if the burnup of the fuel were pushed further, one would face the question of what could be the impact of pin failures and rapid release of plenum gas in such a transient. Also, there are questions about the impact of an unprotected rapid release of plenum gas following the failure of highly irradiated fuel during normal operation. The concerns are mainly in two areas. One area is a structural question relating to possible deformation or breaking of subassembly duct walls because of the high pressure pulse following the sudden failure of a pin. The other area of concern, and the one addressed here, is whether the release of gas from failed pins could interfere with the coolant flow enough to cause melting of the fuel, possibly leading to blockage of the coolant channels. To address this question, the coolant voiding model in the SASSYS-1 code was modified to account for voiding due to gas release from failed pins. This model was used to analyze both unprotected pin failures during normal operation and pin failures during a SHRT-45-type unprotected loss-of-flow (LOF) transient.

• OSTI ID: 5822172
• Report Number(s): CONF-901101--
• Conference Information: Journal Name: Transactions of the American Nuclear Society; (USA) Journal Volume: 62
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
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22 GENERAL STUDIES OF NUCLEAR REACTORS
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220900* -- Nuclear Reactor Technology-- Reactor Safety
ACCIDENTS
BREEDER REACTORS
BUBBLES
BURNUP
COMPUTER CODES
COOLING SYSTEMS
DAMAGE
EBR-2 REACTOR
ENERGY SYSTEMS
ENERGY TRANSFER
EPITHERMAL REACTORS
EXPERIMENTAL REACTORS
FAST REACTORS
FBR TYPE REACTORS
FISSION PRODUCT RELEASE
FLUID FLOW
FLUID MECHANICS
FUEL CHANNELS
FUEL ELEMENT FAILURE
FUEL ELEMENTS
FUEL PINS
HEAT SINKS
HEAT TRANSFER
HYDRAULICS
IRRADIATION
LIQUID METAL COOLED REACTORS
LMFBR TYPE REACTORS
LOSS OF FLOW
MECHANICS
ONE-DIMENSIONAL CALCULATIONS
OPERATION
PASSIVITY
POWER REACTORS
PRIMARY COOLANT CIRCUITS
PUMPS
REACTOR ACCIDENTS
REACTOR CHANNELS
REACTOR COMPONENTS
REACTOR COOLING SYSTEMS
REACTOR CORES
REACTOR OPERATION
REACTOR SAFETY
REACTOR SAFETY EXPERIMENTS
REACTORS
RESEARCH AND TEST REACTORS
S CODES
SAFETY
SINKS
SODIUM COOLED REACTORS
TRANSIENTS
TWO-PHASE FLOW
VOID FRACTION