Deterministic method of evaluating multi-dimensional explosive loads generated by fuel/coolant interaction in uranium-aluminum-fueled reactors

The concern over steam explosions in nuclear reactors can be traced to prompt critical nuclear excursions in aluminum-clad/fueled research reactors as well as explosive events in aluminum, pulp, paper, and steel forging industries. The Reactor Safety Study report prompted an extensive analytical and experimental effort on this issue with respect to power reactors that has extended for more than a decade. This effort significantly improved the fundamental understanding of potential steam explosions in commercial reactors. However, little progress has been made toward applying this knowledge to relatively small aluminum-clad high-power density reactors. Application of power reactor understanding to relatively small high-power density aluminum-clad reactors is difficult due to the differences in geometry, material properties of fuels, and power densities. This paper presents the methodology associated with predicting the effect of a hypothetical steam explosion in the reactor core region on the surrounding structures and on the vessel in the High-Flux Isotope Reactor (HFIR), a small-core, uranium-aluminum-fueled research reactor