Thermal–hydraulic modeling of nanofluids as the coolant in VVER-1000 reactor core by the porous media approach

Abstract

The aim of this study was to perform a thermal–hydraulic analysis of nanofluids as the coolant in the VVER-1000 reactor core using the porous media approach. Water-based nanofluids containing various volume fractions of Al2O3 and TiO2 nanoparticles were analyzed. The addition of different types and volume fractions of nanoparticles were observed to have several effects on reactor thermal–hydraulic characteristics. Based on a porous media approach, each fuel assembly was modeled and divided into a network of volumes or lumped regions, each of which was characterized by a volume average parameter. The conservation equations were discretized by the finite volume method and the obtained non-linear algebraic equations were solved by numerical methods using visual FORTRAN language. Finally, the nanofluids analysis was compared with an analysis of pure water. To validate the applied approaches applied in this study, the results of the model and COBRA-EN code were compared for pure water. The achieved results show that the temperature of the coolant increases with the concentration of nanoparticles. Therefore, the coolant flow rate can be reduced due to the higher heat transfer coefficient of nanofluids compared to pure water.