MHD natural convection and entropy generation of ferrofluids in a cavity with a non-uniformly heated horizontal plate

摘要

Numerical analysis has been performed to study natural convection heat transfer combined with entropy generation of ferrofluid in a square cavity with a non-uniformly heated centered horizontal plate under the influence of inclined uniform magnetic field. The vertical borders of the enclosure are kept at constant low temperatures while the horizontal walls are adiabatic. The centrally located heated plate has a linear changed temperature along the plate. Basic equations formulated in dimensionless primitive variables have been solved by the finite difference method. The impacts of governing parameters such as Hartmann number (HA = 0-100), magnetic field inclination angle (gamma = 0 degrees-90 degrees), dimensionless temperature difference (Omega = 0.001-0.1), nanoparticles volume fraction (phi = 0.01-0.04) and plate non-uniformity parameter (lambda = 0 and 1) on the flow structures, thermal transmission characteristics and entropy generation parameters have been investigated. Computational results have shown that a growth of the Hartmann number decreases the average Nusselt number and average entropy generation. In addition, it is observed that an inclusion of nanoparticles leads to the rise of the heat transfer rate and average entropy generation.