Nusselt Number and Convection Heat Transfer Coefficient for a Coaxial Heat Exchanger Using Al2O3-Water pH=5 Nanofluid

Recently, a new class of fluid made up of metal nano-particles in suspension in a liquid, called nanofluid, appeared. Some numerical studies have shown that these new fluids have a higher heat transfer performance, compared with the conventional liquids. In the present study, we have attempted to study, by experimentation, the thermal performances of a particular nanofluid composed of aluminum oxide ($gamma$ce{Al2O3}) particles dispersed in water for various concentrations ranging from 0 to 4%. The experimental set up is a coaxial exchanger, which is destined to solar application, in which the heating liquid used is the nanofluid studied.