Experimental Thermal Conductivity of Alumina Nanoparticles in Water With and Without Sonication

Experimental thermal conductivity of alumina nanoparticles in water is measured with the transient thermal probe, in the presence of sonication (i.e., with ultrasounds), or not. We investigate two types of alumina particles, with the diameter equal to 7 nm and 50 nm. The experimental results, with and without sonication, show that the effective thermal conductivity is greater for the alumina nanoparticle with the smaller diameter. The effective thermal conductivity is greater in the presence of sonication, with a larger relative increase for the smaller diameter nanofluid. We compare the present experimental thermal conductivity with the empirical/theoretical prediction models of the literature with a reasonable good agreement.