Molecular dynamics study of thermal conductivities of (U0.7−xPu0.3Amx)O2

The lattice parameters and thermal conductivities of Am-containing mixed oxide fuel (U0.7−xPu0.3Amx)O2 (x = 0, 0.03, 0.05, 0.1, 0.15, 0.2, 0.25) have been investigated in the temperature range from 300 to 3000 K using the molecular dynamic (MD) simulation. The calculated results are investigated comprehensively and analyzed systematically with the published literature. It is evident that the lattice parameters follow the Vegard's law and previous data perfectly. On the other hand, the lattice parameters increase with the rising temperature and decrease with the adding Am content. The results we calculated are in good agreement with the experiment values. On the contrary, The Am content barely influences the thermal conductivities of (U0.7−xPu0.3Amx)O2. As the temperature increased, the thermal conductivity decreases clearly. In addition, the supercell size of the unit cell makes little difference on the thermal conductivity compared to the temperature fluctuation.