MOX thermal conductivity (XT-ADS driver fuel) V. Sobolev, B. Arien SCK·CEN, Boeretang 200, Mol, Belgium
Introduction • Isotopic composition of the XT-ADS fuel has been described in Deliverable D1.1 of DM1. • Recommendations on main thermal and mechanical properties of the driver MOX and MA oxide fuels have been presented in Deliverable D3.4 of DM3. • However, uncertainty still exists on irradiation degradation of thermal conductivity and other thermophysical and mechanical parameters of fuel. • Up to now the EFR recommendations (of 1993) are used for irradiation induced degradation of MOX thermal conductivity, in spite of the fact that they are not in good agreement with later published recommendations.
4. Stoichiometry deviation:supplementary thermal resistivity Baron’s correlation overestimates; others are in a good agreement
5. Burnup effect: supplementary thermal resistivity EFR & Philipponneau correlations strongly underestimate; Modified Duriez-NFI gives best estimate for others.
Conclusions • MOX thermal conductivity dependence on Pu content is neglected in most of models. Baron’s correlation takes it into account. • Baron’s correlation overestimates the effects of non-stoichiometry and burnup. • EFR model strongly underestimates the effect of burnup. • HALDEN, Carbajo (Lucata burnup model) and modified Duriez-NFI correlations can be used for prediction of burnup effect in XT-ADS MOX.