The TRIGA IPR-R1, a pool type research reactor located at the Nuclear Technology Development Center (CDTN -Centro de Desenvolvimento da Tecnologia Nuclear) in Campus UFMG, was modeled with the Serpent 2.1.32 and SCALE 6.2.4. The goal is to assess the nuclear data sensitivity of the multiplication factor to the different codes using some neutron cross-section libraries, namely: ENDF/B-VII.1, ENDF/B-VIII.0, JEFF-3.1.3 and JEFF-3.3. The partial results show that Serpent overestimates the multiplication factor of the system when using both JEFF and ENDF libraries at CZP conditions (TF = 300K). While at HFP conditions (TF = 373K), Serpent using JEFF-3.1.3 and ENDF/B-VIII.0 presented larger keff values than SCALE using ENDF/B-VII.1. In general, the different libraries presented good agreement and in future works, burnup calculations will be performed to further study the impact of these libraries in the modelled reactor.

The core of the Angra 2 reactor has been modeled with SERPENT2.1.32 nuclear code using the ENDF/B-VII.1 and JEFF 3.1 cross-section libraries. The objective is to analyze and compare the neutron multiplication factor and check the mass variation of fissile actinides during the burnup, obtained with several libraries for standard UO2 enriched with U-235, mixed oxide fuels (MOX), and reprocessed fuel spiked with thorium (TRU) in a PWR. The parameters were calculated at BOL (Beginning of Life) and during the burnup fuel cycle. The neutron multiplication factor evaluated at BOL and its evolution during the burnup cycle has a consistent result between cross-section libraries used. The difference between the neutronic parameters is expected to increase at the EOC (End of Cycle), mainly due to the distinct nuclear libraries used. The mass variation of fissile actinides also shows good consistency between cross-section libraries.