Safety analysis of small long life CANDLE fast reactor

Safety analysis for small long life fast CANDLE reactor was performed with ULOF (unprotected loss of flow), SDRW (unprotected shut down rods withdrawal), ULOHS (unprotected loss of heat sink) and LB (local blockage) accidents. The employed reactor system is based on the former steady state research. The core with 1.0 m radius and 2.0 m length produces 200 MW thermal power in steady state, using enriched N-15 natural uranium as fresh fuel and lead bismuth as coolant. The former 3 accidents were simulated without scram by neutronic-thermal hydraulic calculation coupled with stationary diffusion calculation. The LB accident was simulated by transient thermal hydraulic calculation only, because in this accident the neutronic factors basically do not change. The analysis results show that the proposed small CANDLE fast reactor can survive all the accidents without any active protection.