HEAT TRANSFER RESEARCH, cilt.52, sa.4, ss.79-93, 2021 (SCI-Expanded)
The use of nano fluids has recently gained importance in studies carried out on increasing reactor efficiency with attention paid on safety factors in nuclear technology. Nanofluids used in reactor cooling water at certain properties and ratios generally use enriched UO2 as fuel. Through the discovery of thorium reserves and its use in nuclear technology, thorium has also become a candidate for being used as a fuel material in reactors. In this study, using ThO2 fuel and Al2O3, CuO, and TiO2 nanoparticles of the coolant in different ratios, the neutronic and thermal properties of the reactor, especially the criticality and temperature of coolant and DNBR as three leading parameters, were investigated. For the analyses, 5%, 10%, 15%, and 20% ThO2 was added to the reactor core containing 3.7% enriched UO2 fuel, and the analyses were performed adding 0.01%, 0.05%, and 0.1% volume of nanoparticles to the coolant water. Neutronic calculations were carried out with the help of MCNP code and COBRA-IV PC code was used for thermal analysis. The obtained results showed that by adding nanoparticles to coolant and using thorium as an additive to fuel the rise of coolant temperature can be augmented by 4.67 K compared to traditional combination of UO2 fuel and water while reactor remained within safety limits.