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 filled
with a porous medium has been carried out in the current study. Polar system has been
selected as coordinate system. As a result, all equations have been discredited in r and θ
directions. Brinkmann extended Darcy model has been utilized to express fluid flow in
porous matrix in the enclosure. Smaller and larger curved walls are supposed to be hot and cold sources, respectively. Other two walls are insulated. The numerical solution has been obtained based on the finite volume methodology via staggered grid system, which will be explained in detail in its respective section. Finally, at the result section the effects of all pertinent parameters i.e. Grashof number, Lewis number, Darcy number, and Buoyancy ratio on the fluid motion and medium thermal behavior have been illustratively discussed. Results reveal that an increasing in Lewis number has a negative effect on heat transfer, while it has a positive impact on mass transfer. It is also seen that the flow intensity is increased by decreasing Lewis number. In addition, it is observed that for the aiding flow case, average Nu and Sh numbers decrease with increasing buoyancy ratio, while for opposing flow cases Nu and Sh augment with decreasing buoyancy ratio.