Research on Pressure Suppression and Against Hydrogen Risk of the SMR in Floating Nuclear Power Plants

Abstract In the event of loss of coolant accident (LOCA) in small modular reactors (SMRs) in floating nuclear power plants (FNPP), appropriate pressure suppression and hydrogen elimination measures must be taken to ensure small modular reactors’ safety. This paper utilizes GASFLOW to analyze the environmental conditions and gas behavior following the implementation of pressure suppression and hydrogen elimination measures in SMRs. The results indicate that: 1) The suppression effect is optimal when the capacity of the suppression pool is 200m3. 2) In cases where the cross-sectional area of the suppression pipeline is either excessively large or small, adverse effects on suppression effectiveness are observed. The study shows that there is an optimal cross-sectional area of suppression pipeline to achieve the best suppression effect of suppression pool. 3) The combination of passive autocatalytic recombiners (PARs) and igniters can safely and efficiently eliminate the risk of hydrogen and have a good hydrogen mitigation effect.