Three dimensional mesoscopic simulation of magnetic field effect on natural convection of nanofluid

New computational approach for exergy and entropy analysis of nanofluid under the impact of Lorentz force through a porous media

Numerical approach for MHD Al2O3-water nanofluid transportation inside a permeable medium using innovative computer method

Magnetic field effect on natural convection in a nanofluid-filled square enclosure

MHD free convection of Al2O3–water nanofluid considering thermal radiation: A numerical study

Effect of a magnetic field on free convection in a rectangular enclosure

Effect of magnetic field on natural convection in a vertical cylindrical annulus

A numerical study is conducted to understand the effect of magnetic field on the flow driven by the combined mechanism of buoyancy and thermocapillarity in a rectangular open cavity filled with a low Prandtl number fluid (Pr = 0.054). The two side walls are maintained at uniform but different temperatures θh and θc (θh > θc), while the horizontal top and bottom walls are adiabatic. A finite difference scheme consisting of the ADI (Alternating Direction Implicit) method, which incorporates upwind differencing for non-linear convective terms and the SLOR (Successive Line Over Relaxation) method are used to solve the coupled non-linear governing equations. Computations are carried out for a wide range of Grashof number Gr ranging from 2 × 104 to 2 × 106, Marangoni number Ma from 0 to 105 and Hartmann number Ha from 0 to 100. The detailed flow structure and the associated heat transfer characteristics inside the cavity are presented. At large Ma, two counter-rotating cells are formed at the upper half and lower half of the enclosure. As Ha increases, the temperature field resembles that of a conduction type and the streamlines are elongated in nature in the horizontal direction. The upper cell is crowded and stretched along the free surface. The average Nusselt number increases with Ma but decreases with Ha.

Combined surface tension and buoyancy-driven convection in a rectangular open cavity in the presence of a magnetic field

A numerical study is presented for magnetohydrodynamic free convection of an electrically conducting fluid in a two-dimensional rectangular enclosure in which two side walls are maintained at uniform heat flux condition. The horizontal top and bottom walls are thermally insulated. A finite difference scheme comprising of modified ADI (Alternating Direction Implicit) method and SOR (Successive-Over-Relaxation) method is used to solve the governing equations. Computations are carried out over a wide range of Grashof number, Gr and Hartmann number, Ha for an enclosure of aspect ratio 1 and 2. The influences of these parameters on the flow pattern and the associated heat transfer characteristics are discussed. Numerical results show that with the application of an external magnetic field, the temperature and velocity fields are significantly modified. When the Grashof number is low and Hartmann number is high, the central streamlines are elongated and the isotherms are almost parallel representing a conduction state. For sufficiently large magnetic field strength the convection is suppressed for all values of Gr. The average Nusselt number decreases with an increase of Hartmann number and hence a magnetic field can be used as an effective mechanism to control the convection in an enclosure.

Natural convection in a rectangular enclosure in the presence of a magnetic field with uniform heat flux from the side walls

Effect of magnetic field on the buoyancy and thermocapillary driven convection of an electrically conducting fluid in an annular enclosure

M. Venkatachalappa

Papers

Effect of a magnetic field on free convection in a rectangular enclosure

Effect of magnetic field on natural convection in a vertical cylindrical annulus

Combined surface tension and buoyancy-driven convection in a rectangular open cavity in the presence of a magnetic field

Natural convection in a rectangular enclosure in the presence of a magnetic field with uniform heat flux from the side walls

Effect of magnetic field on the buoyancy and thermocapillary driven convection of an electrically conducting fluid in an annular enclosure