Mass and heat transfer by natural convection above a concentrated source buried at the base of a shallow porous layer
This paper reports a numerical study of the natural convection flows that are induced by a finite source of heat and chemical constituent localized at the bottom wall of a horizontal porous layer. The focus is on the Darcy flow, and heat and mass transfer that occur in extremely shallow layers. The numerical solutions are based on the complete governing equations including the transient terms. Two typical flow patterns are present in the geometry studied: multiple cells cover the inner region located above the source, while a single cell persists at the extreme end region. A large effort is devoted to study the behaviour of the single cell flows. The effect of the source relative size and its heat strength upon the associated heat and mass transfer is investigated.