Experimental investigation on thermal conductivity of surfactant-less aluminium oxide (Al2O3) in water nanofluid using acoustic velocity measurements

The thermal conductivity of Al2O3-water nanofluid (NF) was investigated in this study utilizing ultrasonic velocity. The change in thermal conductivity was calculated by increasing the weight fraction from 0.01% to 1% for every 10 degrees C elevation in the temperature range of 25-65 degrees C. The thermal conductivity of NF augmented with an enhancement in nanoparticle concentration and rise in temperature. The thermal conductivity of NF was higher than that of basefluid. Finally, the experimental results were compared with classical thermal conductivity models and the thermal conductivity enhancement coefficient was further used to investigate thermal conductivity augmentation.