Double-diffusive flow in a porous right-angle trapezoidal enclosure with constant heat flux

A computation analysis is performed to study double-diffusive natural convection in a right-angle trapezoidal cavity packed with a porous medium. The horizontal top and bottom boundaries are insulated and impermeable. The vertical left sidewall is kept at a constant heat flux and high concentration, whereas the inclined sidewall is held at lower temperature and concentration. The dimensionless nonlinear system is solved by employing the finite difference method along the successive Under Relaxation technique. The findings are compared and validated with the existing literature for the Darcy flow driven through a single buoyancy effect (difference in density is only due to temperature variations) in a porous square enclosure. The numerical results are expressed in the form of streamlines, isotherms and iso-concentrations, and local and average Nusselt and Sherwood numbers. It is observed that the buoyancy parameter reduces the dimensionless temperature of the cavity and increases the dimensionless concentration due to the strong impact of buoyancy. Smaller values of the Lewis number enhance heat transfer, whereas higher values reduce it. Moreover, the Rayleigh number and buoyancy parameter enhance both surface heat and concentration rates.