NUMERICAL STUDY OF SLIP EFFECT AT THE POROUS MEDIUM/FLUID INTERFACE IN AN ENCLOSURE PARTIALLY FILLED WITH A POROUS MEDIUM

摘要

Fluid flow and heat transfer in a cavity partially filled with a porous medium are studied numerically and the finite element method is used to solve the mathematical model based on a one-domain approach. The sketch of a real porous structure obtained by using X-ray computed tomography is imported into the physical model. The flow properties in the transition region and stress jump coefficient at the porous medium/fluid interface are analyzed for different Rayleigh numbers. The numerical results show that the shear stress in the transition region increased quickly compared with those in homogeneous regions. The change rate of velocity is larger than the change rate of shear stress. The coefficient keeps nearly constant at Ra <= 10(4), and increases slowly with the Rayleigh number, then quickly increases when Ra >= 10(6).