Burnup Characteristics of Transuranic Fuel With Burnable Poison in Dual Cooled Annular Rod of VVER-1000

Abstract

Abstract The potentiality of Transuranic (TRU) fuel as dual cooled annular fuel rods with different types of burnable absorbers (BAs)- integrated burnable absorbers (IBAs), burnable poison rods (BPRs), coated absorbers, etc. in the hexagonal assembly of VVER-1000 was studied. Annular 7, Annular 8, and Annular 9 models were taken for various combinations of TRU fuel and BAs. Planned models were simulated in Monte Carlo particle simulation code OpenMC and lattice physics deterministic code Dragon Version5. Burnup-dependent multiplication factors (MFs) were simulated for 3000 effective full power days (EFPDs). Reactivity was calculated by taking 3% neutron leakage. The study showed that both the MF and reactivity for TRU fuel are significantly higher than conventional UO2 fuel. Linear reactivity model (LRM) was applied to find out cycle burnup, discharge cycle burnup, and cycle length. High cycle burnup, discharge burnup, and cycle length have been observed for TRU fuel compared to UO2 fuel. Burnup-dependent atomic concentration graphs showed that slight burn of Np-237, constant concentration for Cm-244, a slight increase for Am-242, and linear burnout of BAs- Gd-155, Gd-155, and Er-167. A lower concentration of Xe-135 has been observed for TRU fuel. Pin power distribution and energy-dependent neutron flux for different models and BAs combinations are also included in this study.