Heat and mass transfer characteristics of double‐diffusive natural convection in a porous annulus: A higher‐order compact approach

Abstract In this paper, we apply a reconstructed higher‐order compact scheme on nonuniform grids to the problem of double‐diffusive natural convection in a vertical porous annulus. The Darcy model is adopted for the fluid flow coupled with energy and mass equations. Computations are carried out in the regime , , , , and , where is the aspect ratio, is the radius ratio, is the Lewis number, is the buoyancy ratio, and is the thermal Rayleigh number. Extensive computations are carried out to investigate the influence of these parameters on the flow and a general pattern of heat and mass transfer characteristics emerges from the study. Particular attention has been paid to the transient flow behavior while investigating the influence of on the buoyancy ratio configuration.