Analysis on IVR in Severe Accident Induced by DVI Line Break

The severe accident induced by direct vessel injection line break was chosen. The responses for debris in lower plenum and lower head of reactor vessel, heat transfer between debris and reactor vessel wall, heat transfer between cavity water and outer wall of reactor vessel, heat flux of different areas after IVR countermeasure was implemented were analyzed. The results indicate that no creep damage is occurred, and the area 4 is likely to be creep damage earliest.