Abstract

In this study the aim is to study the unsteady mixed convection flow of viscous incompressible fluid through a horizontal channel embedded in non-Darcy porous medium with Brinkman-extended Darcy drag, assuming that temperature of the lower wall varies sinusoidally in the direction of the flow and that of the upper wall is uniform. The governing equations of the flow in terms of vorticity equation and energy equations are simulated using the lattice Boltzmann method together with the finite difference successive over relaxation method. The results are presented in terms of streamlines and isotherms showing the effect of Darcy drag and the Forchheimer drag as well as average Nusselt number. The observation from the present investigation is that the average Nusselt number decreases due to increase of the Darcy and Forchheimer drags, which leads to disappearance of the separated flow that developed for the flow of pure fluid as well as reduces the temperature along the heated region of the lower surface, although the periodicity of the wave propagation remains the same but amplitude of oscillation diminishes.

Keywords:

Horizontal channel, mixed-convection, non-darcy, porous-medium,

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The authors have no competing interests.

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