Analysis of the Heat Transfer and Fluid Flow of SiO2-Water Nanofluids in the Shell Side of a Shell-and-Tube Heat Exchanger Using Computational Fluid Dynamics

In response to the imperatives of energy optimization in industrial processes, this research endeavors to examine the potential of SiO2-water nanofluids as heat transfer media within shell and tube heat exchangers. Employing Computational Fluid Dynamics (CFD) simulations using ANSYS Fluent 2023 R1, a comprehensive analysis is conducted, encompassing nanofluid concentrations spanning 0.1% to 1.0% by volume and turbulence regimes across Reynolds numbers ranging from 20,000 to 83,000. The results consistently demonstrate a positive correlation between heat transfer enhancement and particle loading, culminating in a notable 2.1% augmentation in heat transfer coefficient at the highest particle loading and turbulence level under investigation. Notably, the associated escalation in pressure drop, while present, remains relatively modest in comparison to other nanofluids in similar studies. In order to facilitate the practical application of these findings, the introduction of a performance index, representing the ratio of heat transfer enhancement to pressure drop increase, serves as a critical cost-benefit metric. This index highlights that optimal operational conditions for the utilization of SiO2-water nanofluids as coolants in heat exchangers are situated within lower turbulent regimes and particle loading ranges. Ultimately, the study underscores the need to balance the enhancement of heat transfer with the management of pressure drop in such applications.