CFD-Based Investigation of Convective Flow Behavior in a Heat Exchanger with an Internally Corrugated Tube Using Nanofluids

This present research investigates the dynamic and thermal behavior of nanofluids (Al 2 O 3 , CuO and MgO/water) flowing through the annular space of a corrugated tube heat exchanger. The principle objective is to predict the impact of the nanofluid type and corrugated tube geometry on the thermal performance of a counter-current concentric heat exchanger. To explore this impact, a numerical simulation was conducted using CFD software, considering a two-dimensional flow based on the k-ω turbulence model. The parameters examined in this study include nanoparticle volume fractions that range from 1% to 4% for a Reynolds numbers comprised between 3000 and 8000. To validate the simulation model, a rigorous comparison was performed between the obtained results and those obtained by experimental data reported in the literature. This comparison revealed a good agreement, as both simulation and experimental results indicated that the Nusselt number rises proportionally to an increase in the nanofluid’s volume fraction. This simulation also confirmed that integrating corrugations into heat exchangers significantly increased the overall heat transfer coefficient U g from 670 to 815 W/(m 2 · K) for nanofluid having a 4% volume fraction of Al 2 O 3 /water. Furthermore, it has confirmed that improving the heat exchangers thermal performance is enhanced by raising the Reynolds number and the volume fraction of nanofluid. Finally, the simulation revealed that (MgO-water) nanofluid offers the best performance among the tested fluids.