Heat Transfer Enhancement Using Aluminium Oxide-Water Nanofluid in a Concentric Tube Heat Exchanger

Abstract

The enhancement of heat transfer is a central concern in thermal engineering, and nanofluids, formed by suspending nanoparticles in a base fluid, have emerged as a means of improving the thermal performance of conventional fluids. This paper investigates the enhancement of heat transfer using an aluminium oxide-water nanofluid in a concentric tube heat exchanger. The nanofluid was prepared at two volume concentrations, and its convective heat transfer was studied as a function of the Reynolds number and compared with that of water, with the Nusselt number, heat transfer coefficient, and enhancement quantified. The results show that the nanofluid markedly enhanced the heat transfer relative to water, the Nusselt number and heat transfer coefficient increasing with both the Reynolds number and the nanoparticle concentration, with a substantial enhancement at the higher concentration. The enhancement is attributed to the increased thermal conductivity and the effects of the suspended nanoparticles on the flow. The study demonstrates that the aluminium oxide-water nanofluid is an effective heat transfer fluid, illustrating an engineering application of nanotechnology in thermal systems. KEYWORDS: Nanofluid, Heat Transfer Enhancement, Aluminium Oxide,Nusselt Number, Heat Exchanger, Thermal Engineering, Convective HeatTransfer