Experiments on slug impact loading of the reactor vessel head during a postulated steam explosion

A steam explosion in a reactor pressure vessel could cause a strong molten fuel slug impact on the vessel head, whose failure would question the integrity of the reactor containment. The capacity of a typical pressurized water reactor vessel head to carry slug impacts is therefore investigated. The slug interaction with the complex upper internal structures is taken into account. This interaction increases the capacity of the head and reduces its parameter sensitivity. Rough theoretical assessments are presented in this paper. Model experiments are being prepared to obtain reliable results. The similarity conditions for slug-structure impact problems are discussed.