Numerical analysis of effect of magnetic field on combined surface tension and buoyancy driven convection in partially heated open enclosure

Abstract

Purpose – The purpose of the paper is to investigate the effects of magnetic field on the flow driven by the combined mechanism of buoyancy and thermocapillary flow in an open enclosure with localized heating from below and symmetrical cooling from the sides. Design/methodology/approach – The governing equations are discretized by the control volume method with power-law scheme and solved numerically by SIMPLE algorithm for the pressure-velocity coupling together with under-relaxation technique. Findings – In this work, it is observed that, the average Nusselt number, decreases with an increase of Hartmann number Ha, and increases with increase of Prandtl and Grashof number. At large Marangoni number Ma, a prominent secondary eddies are observed at the top of the enclosure due to the effect of surface tension. Originality/value – The study combines many external forces on thermocapillary flow.

Quantification of free convection within a hemispherical annulus through a porous medium saturated by water-copper nanofluid

“…These interesting materials are sometimes saturated with nanofluids consisting of various fluid base and nanoparticles with different volume fractions. Thermophysical characteristics and various aspects of these nanofluids are available in many recent works (Abu-Nada, 2010; Revnic et al , 2018; Nagarajan et al , 2015; Purusothaman et al , 2016; Sabour et al , 2017; Sheikholeslami and Zeeshan, 2018; Ghadikolaei et al , 2018; Sheremet et al , 2017; Baïri et al , 2017). They show that their influence on natural convective heat transfer strongly depends on the combinations of many physical parameters of the considered problem, such as the Rayleigh number, the nature of the nanofluid, its fraction volume, its thermophysical characteristics, the cavity’s geometry and the position of the active device with respect to the gravitational field.…”

Effect of Moving Flat Plate on Mixed Convection Porous Enclosure with Sinusoidal Heating Side Walls and Internal Heat Generation

“…Daniel (2015) examined the detailed discussion of heat generation or absorption on the boundary layer flow of the nanofluid over a porous stretching sheet. Unsteady laminar natural convection in an open enclosure with non-uniform heating bottom wall using magnetic field is premeditated numerically by Nagarajan et al (2015) and they showed that the heat transfer rate augments for the increasing the length of heat source.…”