الفهرس 
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Abstract
ABSTRACT Forced convection flow over a square cylinder embedded in a porous channel is numerically studied. The flow in the porous channel is modeled using steady two-dimensional Brinkman-Forschheimer extended Darcy model and energy equation. The flow over a bare square cylinder in cross flow (without porous medium) is also studied to show the effect of using porous channel. The governing equations are formulated by the stream function and vorticity method and solved by the finite volume procedure. The effects of Reynolds, and Darcy numbers on the streamlines pattern, the fluid flow velocity distribution, the total pressure drop, temperature distribution, and local and average Nusselt number are presented for the range of 5?Re?2000, and 10-8?Da?0.1. The effect of thermal conductivity ratio Rk on the temperature distribution and local and average Nusselt number are also obtained for a range of 0.4?Rk?100. The results show that embedding the cylinder in porous medium of Rk=1 and Da?10-4 increases the average Nusselt number by nearly 100% than it in the case of flow without porous medium due to the increase in convection. An increase in the average Nusselt number occurs with the decrease of Darcy until Da=10-4. At Da<10-4, no change in the average Nusselt is observed and there is no need to decrease the Darcy number further more because this will cost more pumping power with no gain in the heat transfer. As the thermal conductivity ratio increases, the local and average Nusselt numbers increase. At Rk=0.5, Da=10-4 the average Nusselt number is equal to the average Nusselt number of the case of the flow without porous media. So for Rk>0.5 the medium can be considered as conducting medium, while for Rk<0.5 the porous medium is considered as insulating medium. The average Nusselt number is correlated with Reynolds, Darcy numbers, and thermal conductivity ratio Rk.