Numerical simulation of the combined nanofluid effects on heat transfer characteristics in VVER-1000 nuclear reactor

Abstract

Nanoparticles have been investigated during the recent decade. The most important advantage of nanoparticles is increased thermal conductivity coefficient and convection heat transfer coefficient. In this paper, the effects of the combined nanofluid (Al2O3-TiO2/water) on the heat transfer characteristics such as thermal conductivity coefficient, heat transfer coefficient, fuel clad and fuel centre temperatures in VVER-1000 reactor are investigated numerically, based on the K-ωSST Turbulence model. Therefore, at first, the cell equivalents for a fuel rod and its surrounding coolant fluid are obtained in the hexagonal fuel assembly of VVER-1000 reactor. Then, a fuel rod is simulated in the hot channel using CFD simulation codes, and thermo-hydraulic calculations (maximum fuel temperature, fluid outlet, MDNBR, etc.) are done and compared with a VVER-1000 reactor without nanoparticles. As one of the most important results of the conducted analysis, it could be observed that heat transfer and thermal conductivity coefficient increased and DNBR of the nanoparticle combination state was better than that of nanofluid and nanoparticle state. Copyright © 2016 Inderscience Enterprises Ltd.