Effect of Al₂O₃/water nanofluid on performance of parallel flow heat exchangers

A comprehensive experimental investigation is intended to survey consequence of nanofluid on performance of sundry parallel flow heat exchangers with the same heat transfer surface area. An experimental setup including one double-pipe heat exchanger, two shell-and-tube heat exchangers with different tube passes, and one plate heat exchanger is designed and built to carry out the experiments. The experiments are performed under turbulent flow conditions using distilled water and Al₂O₃/water nanofluid with 0.2, 0.5, and 1% particle volume concentrations. Based on the results from this study, the double-pipe heat exchanger reflected the best outcomes in the heat transfer coefficient with a maximum enhancement of 26%, while only a 7% increment in the heat transfer coefficient is observed for the plate heat exchanger. On the other hand, minimum punishment for pressure drop of the working fluids due to adding the nanoparticles is observed in the plate heat exchanger at 1% volume concentration with a maximum value of 10%.