Influence of oriented magnetic field on natural convection in an equilateral triangular enclosure filled with water- and kerosene-based ferrofluids using a two-component nonhomogeneous thermal equilibrium model

In this paper, hydromagnetic natural convection heat transfer in an equilateral triangular enclosure filled with waterand kerosene-based ferrofluids has been analyzed using a two-component non-homogeneous thermal equilibrium model. The enclosure is permeated by an inclined magnetic field of having uniform strength. The effects of Brownian motion and thermophoresis of the nanoparticles are incorporated into the ferrofluid model. The Galerkin weighted residual finiteelement method has been employed to solve the governing nondimensional partial differential equations. Fe3O4-water and Co-kerosene ferrofluids have been used for the present investigation. The effects of various model parameters such as Rayleigh number, Hartmann number, and inclination angle of the magnetic field on the streamlines, isotherms, and isoconcentrations have been displayed graphically. In addition, the heat transfer augmentation for various combinations of model parameters have been done in light of the average Nusselt number from the bottom heated wall. The results indicate that increment in the magnetic field reduces the *Corresponding author: M.M. Rahman, Department of Mathematics and Statistics, College of Science, Sultan Qaboos University, P.O. Box 36, P.C. 123 Al-Khod, Muscat, Sultanate of Oman E-mail: [email protected] Reviewing editor: Bernardo Spagnolo, Università di Palermo, Italy Additional information is available at the end of the article ABOUT THE AUTHOR M.M. Rahman, PhD, is Associate Professor of Applied Mathematics at the Sultan Qaboos University, Sultanate of Oman. He received his MSc degree in 1994 from the University of Dhaka, Bangladesh, and PhD in 2003 in Applied Mathematics from the University of Glasgow, UK. His research interests include mathematical fluid mechanics, nano-fluidic phenomena, magnetohydrodynamics, heat and mass transfer, transport in porous media, and biofluid flows. He has supervised 15 PhD/MSc students. Currently, he is involved in supervising several PhD and MSc students. He has published more than 90 research papers in archived international journals and conference proceedings. He is the principal investigator of several grants funded by The Research Council of Oman and Sultan Qaboos University. He is an active member of several scholarly societies. PUBLIC INTEREST STATEMENT Nanofluids are relatively new class of fluids engineered by suspending nanoparticles with average sizes below 100 nm in traditional heat transfer fluids such as water, engine oil, ethylene glycol, and kerosene. Nanofluids are considered to offer important advantages over conventional heat transfer fluids. A very small amount of nanoparticles, when dispersed uniformly and suspended stably in base fluids, can provide dramatic improvements in the thermal properties of host fluids. The influence of a magnetic field on natural convection has great importance in many industrial and technological applications. Natural convection heat transfer in an equilateral triangular enclosure filled with Fe3O4-water and Co-kerosene ferrofluids in the presence of an inclined magnetic field is investigated using a two-component non-homogeneous thermal equilibrium model. It is found that there exists a strong interaction between cobalt and kerosene in the presence of an inclined magnetic field which can be utilized properly for desired heat transfer augmentation. Received: 21 June 2016 Accepted: 01 September 2016 First Published: 10 September 2016 © 2016 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license. Page 1 of 15 M.M. Rahman