Numerical modelling of double-diffusive natural convection within an arc shaped enclosure filled with a porous medium

Numerical study of double-diffusive natural convective heat transfer in a curved cavity filledwith a porous medium has been carried out in the current study. Polar system has beenselected as coordinate system. As a result, all equations have been discredited in r and θdirections. Brinkmann extended Darcy model has been utilized to express fluid flow inporous matrix in the enclosure. Smaller and larger curved walls are supposed to be hot andcold sources, respectively. Other two walls are insulated. The numerical solution has beenobtained based on the finite volume methodology via staggered grid system, which will beexplained in detail in its respective section. Finally, at the result section the effects of allpertinent parameters i.e. Grashof number, Lewis number, Darcy number, and Buoyancy ratioon the fluid motion and medium thermal behavior have been illustratively discussed. Resultsreveal that an increasing in Lewis number has a negative effect on heat transfer, while it hasa positive impact on mass transfer. It is also seen that the flow intensity is increased bydecreasing Lewis number. In addition, it is observed that for the aiding flow case, averageNu and Sh numbers decrease with increasing buoyancy ratio, while for opposing flow casesNu and Sh augment with decreasing buoyancy ratio.

Keywords:

FVM method , Double-diffusive convection , Arc-shaped cavity , porous media