Magnetic field effect on the unsteady natural convection in a wavy-walled cavity filled with a nanofluid: Buongiorno's mathematical model

• Published in: Journal of the Taiwan Institute of Chemical Engineers 2016-04, Vol.61, p.211-222
• Main Authors: Sheremet, Mikhail A., Pop, Ioan, Roşca, Natalia C.
• Format: Article
• Language: English
• Subjects: Magnetic field; Nanofluid; Numerical results; Unsteady natural convection; Wavy-walled cavity
• ISSN: 1876-1070; 1876-1089
• DOI: 10.1016/j.jtice.2015.12.015

•Unsteady MHD natural convection in a wavy cavity is studied.•Mathematical nanofluid model proposed by Buongiorno is used.•The partial differential equations have been solved using finite-difference method.•It is shown that key parameters have substantial effects on the flow and heat transfer characteristics. A numerical investigation is performed on the unsteady natural convection of water based nanofluid within a wavy-walled cavity under the influence of a uniform inclined magnetic field using the mathematical nanofluid model proposed by Buongiorno. The left vertical wavy and right vertical flat walls of the cavity are kept at constant but different temperatures whereas the top and bottom horizontal walls are adiabatic. All boundaries are assumed to be impermeable to the base fluid and nanoparticles. The mathematical model formulated in dimensionless stream function, vorticity and temperature variables is solved using implicit finite difference schemes of the second order. The governing parameters are the Hartmann number, undulation number, wavy contraction ratio, inclination angle of the magnetic field relative to the gravity vector and dimensionless time. The effects of these parameters on the average Nusselt number along the hot wavy wall, as well as on the streamlines, isotherms and isoconcentrations are analyzed. [Display omitted]