Hydrothermal performance of mini-channel heat sink using nanofluids/hybrid nanofluids: a numerical study

Abstract

We investigated hydrothermal performance of the mini-channel heat sink by using water, and nanofluids/hybrid nanofluids at 1% of volumetric concentration. The water-based nanofluids studied in this work were CuO, TiO2 and Fe2O3 with CuO-TiO2 and CuO-Fe2O3 hybrid combinations. The mean diameter of all the nanoparticles was fixed to be 60 nm. For numerical modeling, multiphase mixture model was used. The maximum heat transfer recorded for CuO and (CuO.75%+ Fe2O3.25%) based nanofluids was 59.12W and 58.27 W, respectively, at maximum Reynolds number of 1750. The maximum percentage increment in heat transfer recorded for CuO and hybrid (CuO.75%+Fe2O3.25%) water-based nanofluids was 29.24% and 24.55%, respectively, then water at minimum Reynolds number of 750. Results are evaluated in the form of the base temperature, thermal resistance, heat transfer, pressure drop and Nusselt number. The minimum base temperature was recorded for CuO-H2O as 35.4 at maximum Reynold number (Re) of 1750 among all the nanofluids/hybrid nanofluids. However, maximum percentage reduction in the base temperature was recorded for CuO-H2O as 7.04% compared with water at minimum Reynolds number of 750. It was observed that nanofluids lead toward high heat transfer.