Analysis of the LBE-Water Interaction in the Lifus 5 Facility to Support the Investigation of a SGTR Event in LFRs

The main purpose of this experimental and computational study is to obtain an assessment of the physical effects following energetic interaction between Iead-bismuth eutectic alloy (LBE) and water; this phenomenon is of great relevance in the analysis of a SGTR (Steam Generator Tube Rupture) accident in a Lead-cooled Fast Reactor (LFR) as ELSY and for the qualification of the models developed for the SIMMER code. The experiment named ELSY-2, performed with the facility LIFUS 5, was analysed with SIMMER code using both the 2D and 3D versions. The calculation models employed in the simulations were realized on the basis of the facility's real technical specifications. In particular, the calculated pressure time trend inside the reaction vessel of LIFUS 5 facility resulted as being in quite good agreement with the experimental data, although both versions of the code tended to overestimate the pressure in the first stage of the transient.