The Effects of Magnetic Field on The Convective Heat Transfer Around a Solid Cylinder Wrapped by a Porous Sheath

The study of an external magnetic field effects on fluid flow and heat transfer characteristic has direct applications to various physical phenomena. In this paper، flow and heat transfer of an electrically conducting fluid around a cylinder wrapped with a porous ring and under the influence of A constant magnetic field has been studied numerically. The range of Stuart (N)، Reynolds (Re) and Darcy (Da) numbers are 0-5، 1-40، and 10-8-10-1 respectively. The Darcy–Brinkman–Forchheimer model has been used for simulating the flow in porous medium. Governing equations provides the coupling between the flow field and the magnetic field. These equations with the relevant boundary conditions are solved numerically using Finite Volume Method (FVM). The effects of varying Stuart، Reynolds، and Darcy numbers on flow patterns and heat transfer rate are explored. Finally، two overall expressions for the average Nusselt number are proposed in which effects of Magnetic field and Darcy number are considered. It was found that in the presence of a magnetic field، the drag coefficient and the critical radius of insulation increases، while the wake length and Nusselt (Nu) number decreases.