Modeling the Mixing and Heat Transfer of Nanofluids in Laminar Flow

Most graphene-based nanoparticles are hydrophobic and cannot form a stable suspension leading to deterioration in the heat transfer characteristic of the nanofluid and causing clogging, which sets the barrier in using these nanofluids as heat transfer fluids in a wide-scale of industrial applications. In this numerical study, a concentrated stream of reduced graphene oxide nanoparticles (rGO) and water is mixed using a Kenics mixer to achieve beneficial heat transfer enhancement at Re=300 and 700. The concentrated stream of nanoparticles represents the fall out of nanoparticles in the unstable nanofluid. The results obtained from this study show that a minimal mechanical mixing within the flow can disperse a concentrated stream of rGO nanoparticles in water to provide beneficial enhancement in heat transfer at a lower energy cost in laminar pipe flow conditions.