A review on latest development in heat transfer through porous media in combination with nanofluids and wavy walls

Abstract

Heat flow through porous media and different phenomenon in these media are studied widely in recent years due to their extraordinary applications in different fields of engineering, bio-engineering and energy systems etc. In this report, recent advances in the numerical investigation of completely or partial filled porous media alone or in combination with wavy walls and nanofluids/nanoparticles have been reviewed. The main emphasis of this is to review the theoretical and numerical aspects of the effect of position of porous insert, nanoparticle volume concentration and the amplitude of the waves associated with wavy channels on the Nusselt number, pressure drop, entropy generation and efficiency of heat transfer. The conditions which define the boundary for the use of LTE (Local thermal equilibrium) and LTNE (Local thermal nonequilibrium) equations for evaluation of the porous media have also been reviewed. The LTE equations were found to be appropriate for the systems in which the temperature different between the solid and fluid phase is very small whereas, if the temperature difference between the two is large, then only LTNE can be employed. The porous media along with wavy walls and nanofluid combinations was found to exhibit better results in terms of Nusselt number and heat transfer efficiency but to obtain bets results, minimum amplitude in case of wavy walls and volume concentration of nanoparticle concentration should be optimized.