Applying phase separation of a solvent system with a lower critical solution temperature for enhancement of cooling rates by forced and free convection

Phase separation of non-ideal solvent system is used for augmentation of the convective single-phase heat transfer rates. A mixture of water and triethylamine with a lower critical solubility temperature is used as a heat sink. It was found that phase separation can enhance significantly the forced convection heat transfer in small diameter pipes (by a factor of up to 7), and the heat transfer coefficient is by a factor of up to 5 larger than that of water with the same volumetric flow rate. Using the same solvent system and inducing phase separation on a hot vertical plate result in augmentation of the free-convection heat transfer rates by a factor of up to 3. Visualization of the flow field near the plate during the phase separation enables to associate the heat transfer augmentation to the observed flow phenomena.