Nanomaterial-engineered fluids in cooling Systems: From preparation to performance–A comprehensive review

The increasing demand for efficient cooling systems in engines, electronics and industrial processes requires advanced and innovative solutions in thermal management. Traditional cooling methods suffer from several limitations, leading to reduced performance and damage of components. Modern cooling systems use nanofluids as coolants offering improved thermal conductivity and heat transfer efficiency. Nanofluids containing metals, metal oxides, carbides, carbon nanostructures (CNTs, Graphene, etc.) exhibit enhanced heat transfer properties with high stability. Nanofluids are developed by using several strategies and it all depends upon involved nanomaterial and fluidic components and also the adopted methodology. The synthesis methodology, key thermophysical properties (thermal conductivity, viscosity, specific heat capacity, density) of nanomaterials and of base fluid determine the final response of nanofluids. By selecting appropriate nanomaterials, the response of nanofluids can be effectively tailored for diverse applications, e.g., microprocessor cooling, automotive radiators, solar collectors, and advanced heat exchangers, etc. Engineered nanofluids could play a potential role in thermal energy harvesting and reuse but the nanoparticle agglomeration, increased viscosity, energy requirements, and environmental concerns, etc., are open challenges. This review presents the state-of-the-art research progress in the direction of smart nanomaterials based advanced nanofluids that could offer potential solutions as promising frontiers in future thermal management. • Reviews nanofluids from preparation methods to thermal performance. • Studies effects of nanoparticle type, size, base fluid, and additives. • Highlights the advances in hybrid and carbon-based nanofluids for cooling. • Summarizes applications in solar, electronic, automotive, and storage. • Discusses challenges and future directions for sustainable nanofluids.