Phase Change Heat Transfer Characteristics of Water/pao Nanoemulsion Heat Ttransfer Fluids

In this study, one type of nano-engineered heat transfer fluids: Water/AOT/Polyalphaolefin (PAO) nanoemulsion fluids are prepared, and their phase change heat transfer properties have been investigated. The Water/AOT/Polyalphaolefin nanoemulsion heat transfer fluids which are thermodynamically stable are spontaneously generated by a self-assembly of dispersed water nanodroplets The results, expressed in terms of surface heat flux as the function of temperature, have shown that liquid-vapor phase change of water nanodroplets has a drastic impact on the boiling behavior of the nanoemulsion fluid studied: the adding of water nanodroplets greatly lowers the nanoemulsion’s boiling point compared to base polyalphaolefin oil while its heat transfer coefficient increases by over 300% after the incipience of boiling. Meanwhile, the addition of water nanodroplets has greatly enhanced the effective specific heat of the base polyalphaolefin oil by over 70% while undergoing liquid-solid phase change. Besides that, the pool boiling trend of these nanoemulsion heat transfer fluids randomly follows two different boiling curves which coincides with the water inner structure variation based on Small Angle Neutron Scattering (SANS) measurement.