Abstract: Interferometry is an optical non-intrusive technique becoming increasingly popular in the flow and heat transfer visualisation and measurement. In the present study, experimental investigation on heat transfer properties of Zinc Oxide (ZnO) Nano fluids using Michelson Interferometry has been carried out. The temperature, at a reference point in the Nano fluid, is recorded by a thermocouple placed at a known distance from the heat source. Interference patterns are captured by a camera and analysed using an image processing tool in MATLAB software. From the observations, it is pellucid that the change of fluid temperature in one path of the coherent laser beam results in the deformation of the interference pattern. Comparison of initial and deformed fringe patterns using digital image processing technique, the temperature distribution near the heat source has been obtained. Recorded interferograms are to be quantitatively analysed to retrieve two dimensional temperature fields. Real time evolution of thermal boundary layers as a function of concentration of Nano fluids is to be recorded in order to understand the plausible role of Nano particle in the heat transfer enhancement.

Keywords: Nano fluids, heat transfer, interferometry, temperature.