218.1 Development of CFD models and pre-test calculations for thermal-hydraulics and freezing experiments on Lead coolant Matteo Iannone Research Centre Rez Hlavni 130 250 68, Husinec-Rez, Czech Republic matteo.iannone@cvrez.cz & GeNERG – DIME/TEC – University of Genova Via all’Opera Pia, 15/A 16145, Genova, Italy s3550241@studenti.unige.it Ivan Dofek, Tomáš Melichar Research Centre Rez Hlavni 130 250 68, Husinec-Rez, Czech Republic ivan.dofek@cvrez.cz, tomas.melichar@cvrez.cz Walter Borreani, Guglielmo Lomonaco GeNERG – DIME/TEC – University of Genova Via all’Opera Pia, 15/A 16145, Genova, Italy walter.borreani@unige.it, guglielmo.lomonaco@unige.it & INFN Via Dodecaneso, 33 16146, Genova, Italy walter.borreani@ge.infn.it, guglielmo.lomonaco@ge.infn.it Vincent Moreau, Manuela Profir CRS4 Scientific and Technological Park, Ed. 1, 09010, Pula, Cagliari, Italy moreau@crs4.it, manuela@crs4.it ABSTRACT Heavy Liquid Metals (HLM) are objects of interest in the nuclear research sector because of their optimal thermal and neutronic properties; the development and the validation of models allowing to predict their behaviour are fundamental for the future development of the Generation IV energy systems. An experimental facility named SESAME-stand, is planned to be operated at Research Centre Rez (RC-Rez) under the framework of SESAME project. The aim of the facility is to study the solidification of Lead under GEN-IV Heavy Liquid Metal pool type nuclear reactors relevant conditions and to provide a database for the benchmarking and validation of