Ionanofluids natural convection heat transfer and entropy generation in a rectangular cavity: Viscosity influence

Abstract

Ionic liquids suspensions with nanoparticles are a new class of heat transfer fluids and this study aim is to outline and discuss the behavior of a new ionanofluid in a real life configuration. If it shortly describes the considered ionic liquid, its main drawback is the high viscosity, thus limiting its applicability in natural convection and turbulent flow applications. In this regard, this research is focused on the study of several suspensions based on a mixture between water and [C2mim][CH3SO3] and alumina nanoparticles behavior in natural convection. The study is considering different high aspect ratio cavities up to 4 and the Rayleigh number varies from 103 to 105. Nusselt number and Bejan number for heat transfer and entropy generation are evaluated. As a main conclusion, it may affirm that heat transfer decreases while the entropy generation increases with the addition of nanoparticles. Finally, even more studies are mandatory, it is recommended to use these new fluids in forced convection instead of natural convection.