High-rayleigh-number natural convection in an enclosure containing a porous layer

摘要

High-Rayleigh-number laminar and turbulent natural convection flows in an enclosure partially filled with a porous layer are studied. A standard k-#epsilon# turbulence model is modified to include the Darcy and Forchheimer terms for turbulent flows in porous medium. The predicted results are compared with published experimental data and numerical simulations. Reasonable agreement is achieved. It is found that when the flow is turbulent in the fluid region, the heat transfer in the porous layer is dominated by convection, and the penetration of fluid into the porous region is more intensive than when the flow is laminar in the fluid region. It is shown that the Darcy and Forchheimer contributions to the turbulent kinetic energy and its dissipation rate can be very significant.