Investigation on thermophysical properties of nanofluids

Nanofluids are promising fluids with particular properties. Several studies have been published in the literature in different sectors like energy, electronics, chemical and medical fields. In particular, nanofluids have been investigated as thermal vectors considering the high thermal conductivity of solid nanoparticles compared to the inherently poor thermal properties of conventional heat transfer fluids. However, literature data are often controversial and nanofluids with a good stability are very difficult to obtain. In the last years, at the Institute of Construction Technologies of the Italian National Research Council, a laboratory for the nanofluids characterization has been built. Here, the stability of new nanofluids is analysed using an instrument based on the Dynamic Light Scattering technique. Subsequently, thermal conductivity and dynamic viscosity can be measured at different temperatures and ambient pressure. If the fluid shows an increase in the thermal conductivity and a low viscosity enhancement, the heat transfer coefficient is studied. A proper apparatus has been created in order to measure the single phase heat transfer coefficient, at constant specific heat flux, in flow regime from laminar to turbulent.