Experimental Investigation of Thermal Performance and Heat Transfer Enhancement in Microchannel Heat Sinks Using Hybrid Nanofluids

Abstract

Microchannel heat sinks (MCHS) have emerged as pivotal thermal management solutions for high-power-density electronic devices, laser diodes, and aerospace systems. However, conventional cooling fluids such as water and ethylene glycol exhibit thermal conductivity, limiting their heat dissipation capabilities under extreme thermal loads. This experimental investigation evaluates the thermohydraulic performance of rectangular microchannel heat sinks utilizing Al2O3-MWCNT hybrid nanofluids across concentrations ranging from 0.05% to 0.5% by volume and Reynolds numbers between 200 and 1200. The results demonstrate a significant enhancement in average Nusselt number, reaching up to 42.5% improvement at 0.5% volume concentration compared to pure water, accompanied by a manageable increase in pressure drop. Comprehensive thermal resistance reductions and performance evaluation criteria (PEC) metrics confirm the superiority of hybrid nanofluids in compact electronic cooling applications.