Experimental investigation of oscillatory heat convection

Nanofluids are used in numerous fields such as optics, pharmaceutical and heat transfer implementations. Due to their high heat transfer performances in heat transfer applications, popularity of nanofluids has quite increased in recent years and according to the records of Web of Science, the number of publications 2010 to 2016 has tripled. Oscillatory flow conditions are also a reformative method for heat transfer and is used in many fields, thermoacoustic coolers are an example. In this study the heat transfer performance between the cold and the hot reservoirs are investigated under oscillatory flow conditions which are connected with a capillary bundle to keep the flow under laminar regime. The chosen parameters for this purpose are oscillation frequency, amplitude and fluid type. Vibrations are applied from the lower surface of the cold reservoir with the shaker and oscillatory flow conditions are formed in the experimental apparatus. The parameters used for this study are 6-10 Hz frequency range, 4.5, 6 mm amplitude, DI water and 2% volumetric water based CuO nanofluid. It is observed that frequency increase shows a parabolic relation with effective thermal diffusivity. Heat transfer rate increases with the increase of displacement for both DI-water and water based nanofluid. In each case, nanofluid has better influence than the DI water in term of total heat transfer.