Synthesis, stability, and heat transfer applications of ternary composite nanofluids-A review over the last decade

The need for more energy to cool thermal systems has increased daily. Such scenarios have prompted researchers to look for alternative, sustainable, and emission-free techniques. Endless endeavors towards the research on composite nanofluids (NFs) ensure that theypossesssuperb heat transfer features. By adjusting the volume concentration of the nanoparticles, the characteristics of mono nanofluids have been improved, but there is a limit to this because of the trade-off of net negative of viscosity growth. Researchers constructed hybrid nanofluids (HNFs) to magnify the special qualities of several kinds of nanoparticles in order to get around this restriction. Early HNF experiments used two-particle NFs, but in more recent years, a noveltype of working fluids namely ternary hybrid nanofluids (THNFs) that contain three solid nanoparticles distributed in a normal fluid have been identified and actively investigated. The novelty of the present study includesthe analysis of all investigations on THNFs regarding theirsynthesis techniques, stability testing, and thermophysical characteristics, and their heat transfer applications to multi-structured devices. In addition, the critical analysis and the future recommendation of the present study are provided. It is observed from the present review analysis that a two-step method is better for synthesis of THNFs. Electro-microscopy and 3ωmethods are favorable for stability analysis of THNFs. Applications of THNFs to several thermal systems yield significantly greater heat transfer rate/cooling so as to amplify their efficiencies.It was specifically observed that CuO−MgO−GO/waterTHNF could boost sustainability by up to 81.10 % in heat exchangers while minimizing the damaging effects of energy loss on the environment by up to 52.32 %. Further research is required to improve THNFs to reduce sedimentation and agglomeration. Therefore,its applications to thermal systems ameliorate their efficiencies significantly.