Simulation of the hydromechanical load to tank internal structures during ''boiling pool'' blowdown

A simulation facility and experimental results are presented which give information about load degradation behaviour of internal tank structures related to the expansion process during ''boiling pool'' blowdown. A ''boiling pool'' is assumed to occur inside the core of a LMFBR during transition phase of a hypothetical loss of flow accident without scram. The ''boiling pool'' consisting of a closed boiling steel/fuel mixture is simulated by a pressure capsule filled with saturated steam and boiling water and the reactor tank internal structure by simple devices installed in a cold water filled steel container