Unsteady MHD Mixed Convection inside L-shaped Enclosure in the Presence of Ferrofluid (Fe3O4)

Mixed convection has been one of the most interesting topics of research in the field of heat transfer for many years. In the present study, unsteady MHD mixed convection heat transfer inside a heated L-shaped enclosure filled with Fe3O4water has been investigated numerically. Lid-motion is introduced by the top wall to induce forced convection. For pure mixed convection (Ri = 1), Grashof number (Gr = 103 - 105) and time (τ) are varied, whereas the solid volume fraction of nanofluid (φ = 0.1) and Hartman number (Ha = 25) are kept constant. Results have been presented in terms of isotherm lines, streamlines, average Nusselt (Nu) number and average temperature (θay). The obtained results show that MHD causes significant effects on heat transfer rate. Interestingly, natural convection is more effective in this case of mixed convection as higher values of Nu are obtained for higher values of Gr.