Conventional fluids with nanometer-sized solid-particles suspended in them, called nanofluids, have been the subject of several investigations regarding pool boiling heat transfer during the past few years. Controversial results about the potential impact of nanofluids on heat transfer intensification have been reported in the literature. The present study is motivated by these conflicting results. This paper is an experimental investigation of boiling heat transfer of Al2O3/ethylene glycol-water (60/40) nanofluids containing 0.1, 0.2, 0.5 wt. % of nanoparticles. The results indicate that a considerable boiling heat transfer enhancement can be achieved using nanofluid as compared with the base fluid. The enhancement increases with increasing particle concentration and reaches 64% at a nanoparticle loading of 0.5% by weight under heat flux of 113 kW/m2. Whereas mixtures of ethylene glycol and water are considered to be the most common water-based antifreeze solutions used in cooling systems, using low concentration Al2O3/ethylene glycol-water nanofluids may help to improve the heat transfer performance of these systems.

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