Abstract
The SMART reactor core has been analyzed for UO2, mix oxide fuel (MOX) fuel (PuO2 with 3.0 wt% and UO2 with 97.0 wt%), and (U-Th)O-2 fuel. The burnup, Doppler reactivity coefficient (DRC), effective multiplication factor (k(eff)), thermal neutron flux, power peaking factor (PPF), and moderator temperature coefficient (MTC) have been studied for (MOX), (U-Th)O-2,O- and UO2 fuels. The MOX fuel has been introduced as a hybrid core, whereas (U-Th)O-2 fuel configuration has been studied as the homogeneous and heterogeneous configuration in the fuel assemblies. The k(eff) has also been assessed versus fuel temperature, burnup, and fuel cycle. The burnup of one complete fuel cycle has been compared for (MOX), (U-Th)O-2,O- and UO2 fuels. The k(eff) has decreased monotonically between 500 and 700 K and was found to be 1.262, 1.149, 1.221, and 1.240 for UO2, MOX, homogenous (U-Th)O-2,O- and heterogeneous (U-Th)O-2 configuration of fuel, respectively. The most negative value of DRC has been found at 600 K, which is - 4.740 pcm K-1, - 3.496 pcm K-1, - 4.896 pcm K-1, and - 4.8260 pcm K-1, for UO2, MOX, (U-Th)O-2 homogeneous, and (U-Th)O-2 heterogeneous configurations at the temperature gradient of 300 K. The maximum PPF has been found as 0.926, 0.964, 0.912, and 0.9750 for UO2, homogeneous configuration of (U-Th)O-2,O- the heterogeneous configuration of (U-Th)O-2 and MOX fuel. The DRC and MTC became more negative at the end of the fuel cycle due to decreased burnup. The (U-Th)O-2 in both configurations has presented a titivated response compared to the reference core between 500 and 1000 K. The MOX fuel has shown less response than (U-Th)O-2 configurations because of the high resonance absorption coefficient of plutonium.