Experimental and Numerical Determination of Interface Slip Coefficient of Fluid Stream Exiting a Partially Filled Porous Medium Channel

Abstract

Stacks of parallel plates modeled as a standard fissuretype anisotropic porous medium are filled inside a rectangular channel up to half the cross section height. The interface slip coefficient خ± for the isothermal laminar incompressible flow exiting this partially filled porousmedium channel is then determined using particle image velocimetry (PIV) experiments and numerical simulations. Required measurements of the Darcy velocity uD on the porousmedium (PM) side, the local velocity uf, and its gradient ∂uf/∂y on the clearfluid (CF) side are performed across different length scales. The fissuretype porousmedium parameters are systematically varied in the porosity range 0.2≤د†â‰¤0.95 and flow direction permeability 106<K,m2<109. From the exitvelocity profile, the empirical slip coefficient خ± is determined using a generalized relationship. When the measurements across the PMCF interface are performed across a length scale equal to the representative elemental length (REL) of the porous media considered (i.e., equal to the sum of plate thickness (a) and gap (b)), the determined خ± value is found to remain invariant.