Inherent Safety of Fuels for Accelerator-Driven Systems

Journal Article · Thu Sep 15 04:00:00 EDT 2005 · Nuclear Technology

OSTI ID:20840305

Eriksson, M; Wallenius, J; Jolkkonen, M; Cahalan, J E

Transient safety characteristics of accelerator-driven systems using advanced minor actinide fuels have been investigated. Results for a molybdenum-based Ceramic-Metal (CerMet) fuel, a magnesia-based Ceramic-Ceramic fuel, and a zirconium-nitride-based fuel are reported. The focus is on the inherent safety aspects of core design. Accident analyses are carried out for the response to unprotected loss-of-flow and accelerator beam-overpower transients and coolant voiding scenarios. An attempt is made to establish basic design limits for the fuel and cladding. Maximum temperatures during transients are determined and compared with design limits. Reactivity effects associated with coolant void, fuel and structural expansion, and cladding relocation are investigated. Design studies encompass variations in lattice pitch and pin diameter. Critical mass studies are performed. The studies indicate favorable inherent safety features of the CerMet fuel. Major consideration is given to the potential threat of coolant voiding in accelerator-driven design proposals. Results for a transient test case study of a postulated steam generator tube rupture event leading to extensive coolant voiding are presented. The study underlines the importance of having a low coolant void reactivity value in a lead-bismuth system despite the high boiling temperature of the coolant. It was found that the power rise following a voiding transient increases dramatically near the critical state. The studies suggest that a reactivity margin of a few dollars in the voided state is sufficient to permit significant reactivity insertions.

• OSTI ID: 20840305
• Journal Information: Nuclear Technology, Journal Name: Nuclear Technology Journal Issue: 3 Vol. 151; ISSN 0029-5450; ISSN NUTYBB
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
ACCELERATORS
BISMUTH
CERAMICS
COOLANTS
CRITICAL MASS
DESIGN
LEAD
MOLYBDENUM
NUCLEAR FUELS
PITCHES
REACTIVITY
REACTIVITY INSERTIONS
RUPTURES
SAFETY
STEAM GENERATORS
TRANSIENTS
ZIRCONIUM NITRIDES