This paper is concerned with the effects of Nield number on heat transfer in a straight channel occupied by a porous medium. Investigation of force convective heat transfer of nanofluids in a porous channel has not been considered completely in the literature and this challenge is generally considered to be an open research topic that may require more study. The present work is an extension to our previous paper (see Maghrebi et al. [24]); such that three-equation energy model, for fluid/particle/solid phases, is employed in the porous channel. Moreover, one heat flux model is proposed. The fully-developed flow and steady Darcy-Brinkman equation is employed in the porous channel. The local thermal nonequlibrium model is assumed between fluid, particles and solid phases. It is assumed that the nanoparticles are distributed non-uniformly inside the channel. As a result, the volume fraction distribution equation is also coupled with other governing equations. The effects of Nield number and modified thermal capacity ratio on the heat transfer are completely studied.

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