BEHAVIOR OF MIXED-OXIDE FUEL-ELEMENTS DURING AN OVERPOWER TRANSIENT

[摘要] A slow-ramp (0.1%/s), extended overpower (almost-equal-to 90%) transient test was conducted in EBR-II on 19 mixed-oxide fuel elements with conservative, moderate, and aggressive designs. Claddings for the elements were Type 316, D9, or PNC-316 stainless steel. Before the transient, the elements were preirradiated under steady-state or steady-state plus duty-cycle (periodic 15% overpower transient) conditions to burnups of 2.5-9.7 at%. Cladding integrity during the transient test was maintained by all fuel elements except one, which had experienced substantial overtemperature in the earlier steady-state irradiation. Extensive centerline fuel melting occurred in all test elements. Significantly, this melting did not cause any elements to breach, although it did have a strong effect on the other aspects of fuel element behavior.

[发布日期] 1993-09-01

[效力级别]  Proceedings Paper