Al2O3 nanofluids were prepared with 2, 3, and 4 vol% Al2O3 nanoparticles in water for use as a coolant in plate heat exchangers. Using the transient plane source (TPS) technique, the thermophysical properties of the nanofluids were studied. Correlation equations were obtained for Nusselt number and the friction factor for the nanofluids and water. Less nanofluid is required to produce the same amount of cooling than water....