One of trends in the ATF fuel design is to add a secondary phase with high thermal conductivity and low neutron absorption into the UO2 fuel matrix. In this work, the SiC is selected as an additive since its behaviour under neutron... more
One of trends in the ATF fuel design is to add a secondary phase with high thermal conductivity and low neutron absorption into the UO2 fuel matrix. In this work, the SiC is selected as an additive since its behaviour under neutron irradiation is well understood. For the assessment of SiC influence on the fuel performance during burnup, the FEMAXI6 code is used. In the work, the source code was modified by introduction the SiC material models of density, thermal conductivity, thermal expansion, heat capacity, Young modulus, and Poisson ratio. The SiC influence on fuel behaviour during normal operation conditions is evaluated using a simple onepellet model loaded with constant linear heat generation rate and different fractions of SiC are then assumed. The results shows that introduction of SiC decreases fuel centreline temperature, fission gas release, plenum pressure and the pellet expansion due to the swelling is lower as well.
