Risks and analyses about fuel rod as being surrounded by concentric layers of oxide, crud and precipitate during the post-LOCA of CPR100

The risks about oxide, crud and chemical precipitate around the fuel rod during the post-LOCA of CPR1000 were analyzed. In an extreme condition, by using the steady-state thermal analysis module of ANSYS, based on the different thickness and the thermal conductivity of the fuel rod as being surrounded by concentric layers of chemical precipitate of AFA-3 G fuel assembly to analyses the effect on heat transfer. Under the conservative boundary conditions, the calculation results had showed that the maximum temperature of the surface of fuel rod cladding was 305.02℃, less than 426.7℃. In the extreme conditions, fuel rod thermal situation was still acceptable during the post-LOCA of CPR1000. (authors)