Thermal Nanofluid Property Model With Application to Nanofluid Flow in a Parallel Disk System—Part II: Nanofluid Flow Between Parallel Disks

Abstract

This is the second part of a two-part paper which proposes a new theory explaining the experimentally observed enhancement of the thermal conductivity, knf , of nanofluids (Part I) and discusses simulation results of nanofluid flow in an axisymmetric jet-impingement cooling system using different knf -models (Part II). Specifically, Part II provides numerical simulations of convective nanofluid heat transfer in terms of velocity profiles, friction factor, temperature distributions, and Nusselt numbers, employing the new knf -model. Flow structures and the effects of nanoparticle addition on heat transfer and entropy generation are discussed as well. Analytical expressions for velocity profiles and friction factors, assuming quasi-fully-developed flow between parallel disks, have been derived and validated for nanofluids as well. Based on the numerical simulation results for both alumina-water nanofluids and pure water, it can be concluded that nanofluids show better heat transfer performance than convectional coolants with no great penalty in pumping power. Furthermore, the system’s entropy generation rate is lower for nanofluids than for pure water.