DOUBLE-DIFFUSIVE NATURAL CONVECTION IN AN ENCLOSURE FILLED WITH FLUID-SATURATED POROUS MEDIUM: A GENERALIZED NON-DARCY APPROACH

Abstract

The double-diffusive natural convective flow within a rectangular enclosure has been studied using a generalized porous medium approach. The results have been validated with the help of theoretical heat transfer results available for various porous medium flow models and also with the experimental results for double-diffusive convection in a fluid-filled rectangular cavity. The present generalized model covers the entire range from Darcy flow to free fluid flow. Numerical predictions by the model indicate that the flow pattern as well as the heat and mass transfer are profoundly influenced by the buoyancy ratio. Also non-Darcy effects on flow, heat, and mass transfer become significant when the Rayleigh or Darcy numbers are large. The Sherwood and Nusselt numbers become sensitive to bed porosity variation in the non-Darcy regime.