Operational safety experience gained with KNK II

KNK II, a 20 MWe Fast Reactor Experimental Power Station, has been operating with its first core load for more than 370 EFPD. Routine operation and unexpected occurences (such as gas entrainment and defect fuel) have proved the excellent safety behaviour of the plant. Extensive studies within the reactor and parallel on models have led to an improved design of the sodium core inlet to be realized with the second core. The experimental program carried out with emphasis on the dynamic behaviour of the reactor, sodium instrumentation, defect fuel detection and steam generator examination rounds up the operational safety experience