Laminar Forced Convection Heat Transfer and Pressure Drop of Water Based Ferrite Nanofluids in Minichannels

Abstract

In this study, the forced convection heat transfer characteristics of water-based cobalt ferrite nanofluids (waterCoFe2O4) were numerically investigated in horizontal circular minichannels. The effects of two different minichannel diameters (D = 1mm and D = 2mm), particle volume ratio (ϕ= 0, 0.25, 0.5 and 1.0) and Reynolds number on thermal performance were investigated. In the study carried out under steady-state conditions, the solutions were solved planar in two dimensions using commercial computational fluid dynamics code ANSYS-FLUENT. Constant heat flux was applied to the surface of the minichannels. The thermophysical properties of water-CoFe2O4 nanofluids were defined as a fourth order polynomial dependent on temperature. The results are presented with suitable outputs in terms of pressure drop and heat transfer. The addition of cobalt ferrite nanoparticles resulted in an increase of 1.9% to 6.5% in heat transfer relative to the base fluid. Similarly, increasing the diameter of the minichannel from 1mm to 2mm has provided a minimum 16.1%, maximum 22.5% increase in heat transfer and a decrease between 85.0% and 87.3% in pressure drop. Total heat transfer improvement has been provided for all situations studied. The highest heat transfer improvement was achieved at the minichannel diameter of 1mm, the lowest Reynolds number and the highest particle volume ratio. © 2022 American Institute of Physics Inc.. All rights reserved.