Abstract:

The natural convection and entropy generation during double-diffusive MHD natural convection in a tilted
sinusoidal corrugated porous enclosure is investigated numerically in this work by using heatline visualization
technique. The top and bottom horizontal walls are assumed as adiabatic and non-diffusive, while
the left and right vertical corrugated sidewalls are maintained at a constant hot and cold temperatures
and concentrations respectively. The flow in the enclosure is subjected to an inclined magnetic field. The
enclosure is filled with an electrically conducting fluid [Pr = 0.024] saturated with a porous media. The
numerical computations are presented for various values of Rayleigh number (Ra), Hartmann number
(Ha), Lewis number (Le), Darcy number (Da), buoyancy ratio (N), magnetic field orientation angle (?)
and enclosure inclination angle (?). In addition, the entropy generation due to fluid friction, thermal gradients,
diffusion, and magnetic field beside the total entropy generation are studied and discussed. It is
found that the flow circulation decreases strongly when the magnetic field applied horizontally and the
enclosure is considered vertical. Heatline visualization concept is successfully applied to the considered
problem. The average Nusselt number decreases when the Lewis number increases, while the average
Sherwood number increases when the Lewis number increases. Also, both average Nusselt and Sherwood
numbers increase when the Darcy number and buoyancy ratio increase. Moreover, the results show
that the entropy generations due to magnetic field when the enclosure is subjected to the horizontal
magnetic field are higher than the corresponding values when it subjected to the vertical magnetic
field.