페이지 정보2017.02.07 / 519
In-Vessel Retention by
External Reactor Vessel Cooling (IVR-ERVC) is one of the severe accident
management strategies to terminate or mitigate the severe accident (SA) which
is also called ‘core-melt accident’. The reactor vessel which is containing
molten core material in the lower head is cooled by flooding coolant. The
molten core mixture is expected to be divided into some layers due to the
density difference. Fig.2 shows the conventional two layered configuration of
IVR. It has light metal layer of Fe-Zr and the ceramic pool of UO2 and ZrO2.
The crust would be formed along the oxide layer boundary. The oxide layer
contains majority of the nuclides which generates the decay heat. If the
generated heat is not removed properly, vessel failure would occur.