Copyright　©　2018　ASME　In-vessel-retention　(IVR)　has　become　an　important　subject　of　severe　accident　mitigation　strategy.　Up　to　now,　many　experimental　and　numerical　investigations　have　been　performed　on　the　natural　convection　characteristics　in　melt　pools　with　volumetric　heating.　But　these　studies　are　limited　to　the　melt　pools　under　static　condition.　As　floating　nuclear　reactors　become　increasingly　popular　among　both　commercial　and　military　ships,　for　successful　application　of　IVR　in　this　occasion,　research　should　be　done　on　the　heat　transfer　characteristics　of　melt　pool　under　moving　conditions.　Currently,　the　specially-designed　facility　is　under　construction　in　Xi＇an　China　for　the　relevant　experiment　and　numerical　studies　are　performed　beforehand.　In　this　paper,　a　hemisphere　with　an　inner　radius　of　0.5m,　similar　to　LIVE　experimental　facility,　is　chosen　to　simulate　the　melt　pool.　Its　flow　behaviors　under　periodic　rolling　condition　are　simulated　by　means　of　CFD　calculation.　This　work　may　cast　a　light　on　the　melt　pool　characteristics　under　moving　conditions　and　could　be　further　evaluated　by　future　experimental　data.