THE EFFECT OF UTILIZING Al2O3-SiO2/DEIONIZED WATER HYBRID NANOFLUID IN A TUBE-TYPE HEAT EXCHANGER

Abstract

One of the significant issues in energy conversion systems is efficient heat transfer which is generally done by heat exchangers (HEs). Different ways have been utilized to increase the performance of HEs. One of these ways for enhancing heat transfer rate is using a nanofluid. In this experimental work, the effect of utilizing Al2O3-SiO2/deionized water hybrid nanofluid at various particle ratios on the efficiency of parallel flow tube-type heat exchanger (PFTHE) and counterflow tube-type heat exchanger (CFTHE) has been investigated experimentally. Hybrid nanofluids have been made by dispersing Al2O3-SiO2 nanoparticles in water at weight concentrations of 0.5, 1, and 1.5%. In addition, to avoid sedimentation and also to improve stability of hybrid nanofluids, surfactant has been added into the nanofluid. The tests have been performed in different configurations to illustrate the effect of utilizing hybrid-type nanofluids. Using Al2O3-SiO2/deionized water hybrid nanofluid led to a maximum enhancement of 25%, 60%, and 67% of the overall heat transfer coefficient at 0.5%, 1%, and 1.5% nanoparticle ratio, respectively.