A review on preparation methods, stability and applications of hybrid nanofluids

Hybrid nanofluid is a new class of nanofluids engineered by dispersing two different nanoparticles into conventional heat transfer fluid. Hybrid nanofluids are potential fluids that offer better heat transfer performance and thermo-physical properties than convectional heat transfer fluids (oil, water and ethylene glycol) and nanofluids with single nanoparticles. Scientific findings have indicated that hybrid nanofluid can replace single nanofluid since it provides more heat transfer enhancement especially in the areas of automobile, electro-mechanical, manufacturing process, HVAC and solar energy. In this paper, we summarized the recent progress related to preparation methods of hybrid nanofluids, factors affecting their stability, methods of enhancing thermal properties and current applications of hybrid nanofluids. Finally, some challenging issues that need to be solved for future research are discussed.