Heat transfer and flow characteristics of nanofluid in a narrow annulus: Numerical study, modelling and optimisation

Abstract

This study attempts to evaluate the flow and heat transfer characteristics of water–Al2O3 nanofluid in a narrow annulus. The effects of volume fraction, the size of particles and the ratio of inner wall heat flux to outer wall heat flux were investigated on the convective heat transfer coefficients and friction coefficients at inner and outer walls of the annulus. Using smaller particles caused a greater heat transfer coefficient. Meanwhile, at higher volume fractions, changing the size of particles led to more considerable changes in the convective heat transfer coefficient and friction coefficient. As per the observation made, the value of heat transfer coefficient at the inner wall was larger than that of the outer wall. In contrast with the results of applying constant properties, changing the volume fraction will change the friction coefficient in the case of using variable properties. Moreover, genetic algorithm was used in combination with compromise programming in order to find the optimum values of the input parameters using neural network correlation.

How do you write and present research well? 6—Tell it in the title

“…Heat Transfer and Flow Characteristics of Nanofluid in a Narrow Annulus: Numerical Study, Modelling and Optimisation [11] [p. 747]…”

Numerical simulation of nanofluids forced convection in a corrugated double‐pipe heat exchanger

“…[ 12,13 ] As a new type of working material, nanofluids have been widely applied in microchannels, [ 14 ] photothermal conversion, [ 15 ] as well as heat exchangers. [ 16,17 ] In recent years, TiO 2 nanofluids have become a research hotspot because they can efficiently enhance the thermal conductivity of fluids and have better dispersion stability than other metal oxide nanofluids. [ 18 ] To date, the study of TiO 2 in heat exchange systems has primarily concentrated on the influence of mass fraction of nanoparticles on thermal transfer properties and stability of nanofluids.…”

Shielding Gas Coaxial Jet Pipes Numerical Study of a Vertical Laser Welding Process of AZ91 Magnesium Alloy

“…Many research reported a significant progress achieved when dealing with the coaxial free jets, which improves the region of the potential core and the turbulence intensity at the nozzle outlet due to the presence of mixing of the primary and secondary streams. Coaxial flows are used in novel domains for instance in the non-Newtonian nanofluid in heat exchangers (Bahiraei et al 2014, Bahiraei 2016, Bahiraei et al (2017a, 2017b).…”