ABSTRACT
In this report is presented a simple and accurate method based on moiré deflectometry for studying of nanofluids' thermal conductivity, containing gold nanoparticles suspended in a liquid medium. A collimated laser beam passes through a cell of nanofluids and then enters a moiré deflectometer. Due to a temperature gradient in the nanofluids, a prism-like medium is formed. The propagation direction of the beam is changed and the moiré fringes are displaced. Finally, thermal conductivity of the nano-fluids may be determined from the moiré fringe displacement. The temperature gradient is then calculated using a simple model based on the Fourier law of heat transfer. This model is expected to reasonably predict the temporal evolution of nanofluid temperature gradient.