Empirical investigation of nanofluid performance in a microchannel heat sink for various attributes in low Reynolds number range

Abstract

Efficient cooling techniques are imperative and present a significant challenge in the electronics industry due to the increasing miniaturization of devices. Elevated temperatures on the surface of components pose a particular concern within the low Reynolds numbers range due to back axial conduction. The current research endeavours to provide an experimental assessment of cooling efficacy, heat transfer coefficient, thermohydraulic performance and loss in concentration utilizing alumina nanofluids with 1–4 % (w/w) concentration in a microchannel heat sink at low Reynolds numbers (10 ≤ Re ≤ 50). The findings indicate notably, the introduction of nanofluids resulted in a 51.54 % reduction in back axial conduction in the microchannel heat sink compared to base fluid, consequently yielding surface temperatures up to 29 % lower in the microchannel heat sink and a substantial enhancement in heat transfer coefficient and Nusselt number up to 43.34 % and 35.85 %, respectively at Reynold number 50. The optimal thermohydraulic performance was noted to be 1.17 at a 3 % (w/w) nanoparticles concentration and Reynold number 50. Correlations have been devised to predict the Nusselt number and friction factor for the microchannel heat sink based on the corresponding nanofluid concentration. The increase in heat transfer coefficient was elucidated by considering thermophoresis and Brownian motion of nanoparticles in the base fluid. In conclusion, this study affirms the potential of nanofluids in efficiently cooling electronic devices, showcasing superior heat transfer performance at low Reynolds number.