[3F06-10] Small Modular Reactor

[3F08] Development of an innovative small sodium-cooled fast reactor

(12) 3D thermal hydraulic transient analysis of RVACS heat removal characteristics

*Guillaume Laurent Grandjean¹, Hirotaka Nakahara¹, Takashi Abe¹, Kazuhiro Fujimata¹, Kazuhiko Matsumura¹ (1. HGNE)

Keywords:Sodium cooled Fast Reactor (SFR), RVACS, Natural circulation, Heat removal, Passive safety, Computational Fluid Dynamics, STAR-CCM+

In the framework of the development of the design of a Sodium cooled Fast Reactor (SFR) Reactor Vessel Auxiliary Cooling System (RVACS), 3D thermal-hydraulics transient analyses are performed to validate the capability of the RVACS to remove passively decay heat from the reactor using natural circulation. A short-term thermal-hydraulics analysis of a Loss Of Heat Sink (LOHS) transient has been carried out using a 3D CFD calculation code (STAR-CCM+). Analyses results showed the transition from forced circulation to natural circulation of primary coolant inside the reactor vessel and the evolution of the RVACS heat removal capacity in the first hour of the transient.