Spent nuclear fuel in dry storage conditions - current trends in fuel performance modeling

The role of dry storage in spent nuclear fuel management becomes more and more important. Originally intended to serve as a temporary solution for a few decades until final disposal, now dry storage period is to be extended to 100 years and beyond. It has to be proven for licensing that the fuel rod integrity during dry storage is ensured. Since it is difficult to provide experimental support, the licensing process has to rely largely on numerical simulations. This paper reviews the literature associated with the modeling of spent nuclear fuel under dry storage conditions. The main phenomena threatening the fuel rod integrity and the numerical models representing them are described here. Moreover, the most recent or currently ongoing experimental efforts that could support the modeling of nuclear fuel in dry storage in the future are discussed. Finally, this paper reviews approaches to dry storage modeling chosen by different countries. In general, these approaches are similar and can be described as a calculation chain consisting of neutronics-thermo-hydraulics-fuel performance computations where sensitivity and uncertainty studies are crucial elements. (c) 2021 Elsevier B.V. All rights reserved.