Effects of Fuel Failure on Criticality Safety and Radiation Dose for Spent Fuel Casks

摘要

Irradiation of nuclear fuel to high-burnup values increases the potential for fuel failure during normal and accident conditions involving transport and storage. The objective of this work is to investigate the consequences of potential fuel failure on criticality safety and external dose rates for spent nuclear fuel (SNF) storage and transport casks, with emphasis on high-burnup SNF. Analyses were performed to assess the impact of several damaged/failed fuel scenarios on the effective neutron multiplication factor and external dose rates. The damage or failure was assumed to occur during use in storage or transport, particularly in an accident. Although several of the scenarios go beyond credible conditions, they represent a theoretical limit on the effects of severe accident conditions. Further, the results provide a basis for decision making with regard to failure potential and a foundation to direct future investigations in this area.