Code Validation of SAM Using Forced and Natural-Circulation Data from NACIE-UP Benchmark

Heavy liquid metals (HLMs) are promising candidates as coolants of GEN-IV fast reactors due to their thermo-physical properties. In the last decade, experimental works have been proposed as part of R&D efforts to develop advanced reactors. In this context, the NACIE-UP facility at the ENEA Brasimone Research Centre (Italy) has conducted many experiments to study the thermo-fluid dynamic behavior of HLM in rod bundle configurations. In the present work, SAM, a modern system analysis code developed at Argonne National Laboratory, is validated with experiments from the NACIE-UP facility. This facility consists of a rectangular loop operated with lead-bismuth eutectic (LBE). A wire-spaced 19-pin fuel bundle simulator is installed on the bottom of the riser portion of the experimental loop, which is equipped with a set of sensors to monitor relevant parameters, i.e., temperatures, heat transfer, and flow conditions (mass flow rate) at different locations. Both natural circulation and forced convection cases were addressed. The SAM model developed in the present work agrees with the experimental facility. Relative errors for temperatures and mass flow rates are within the uncertainty of closure models used in the SAM compared to experimental results.