Neutronic Evaluation of Light Water Reactor-Based Small Modular Reactor With Transuranic Fuel and Comparison With Different Core Configuration of UO2 and Mixed Oxide Fuel

Abstract

Neutronic and burnup assessment of a light water reactor (LWR)-based small modular reactor (SMR) core with transuranic fuel (TRU) was carried out and compared with UO2 fuel and mixed oxide fuel (MOX) for different core composition and configurations. Eight different cores were modeled by changing the fuel composition and loading pattern of four different fuel assemblies, namely, UO2, MOX, TRU, and annular UO2 fuel and simulated in open-source Monte Carlo code OpenMC. The radial neutron flux distribution and maximum to average flux ratio were studied. The lowest flux ratio was found in annular-2 models, whereas TRU models showed the highest value. The effect of enrichment, fuel burnup, moderator to fuel ratio, and soluble boron concentration on effective multiplication factor (keff) was investigated. Burnup analysis of fissionable materials and neutron poison was performed. Burnup-dependent fission rate of U-235, Pu-239, and Pu-241 was also studied. The composition of spent fuel at end of the cycle (EOC) was investigated and lower minor actinides (MAs) production was observed for TRU models. This analysis would help to determine the effectiveness and feasibility of these potential core configurations and to predict their neutronic behavior.