Prediction of ceramic foams permeability using Ergun's equation

Abstract

SiC-Al2O3 ceramic foams with 30 to 75 pores per linear inch (ppi) were used to access the application of pore size obtained by image analysis to estimate the cellular materials permeability through Ergun's equation. Samples were sliced and the pore size distribution, cross-sectional porosity and pore density were evaluated as a function of the slice thickness based on optical and X-ray computerized tomography acquired images. The average pore sizes were used to calculate permeability constants (k1 and k2) of Ergun's equation, which were compared to those experimentally obtained under water flow. Results indicated that the optical diameter distribution was very sensitive to the number of pore layers. Deviation between experimental and calculated values depended on the slice thickness. Nevertheless, the introduction of pore size obtained by image analysis into Ergun's equations seems to give fair results to assess the permeability of ceramic foams

Darcian permeability constant as indicator for shear stresses in regular scaffold systems for tissue engineering

“…Permeability is a measure of the ability of a porous medium to transmit fluids through its interconnected pores or channels. Two permeability parameters, known as the Darcian, k 1 , and the non-Darcian, k 2 , permeability constants, can be found in the Forchheimer equation (Innocentini et al 1999). The Darcian permeability constant is related to the pure laminar flow properties while the non-Darcian permeability constant represents deviations from laminar flow.…”

“…Ergun proposed empirical expressions to describe the two permeability parameters for packed columns made of grains (Innocentini et al 1999;Nield and Bejan 2006). These expressions are:…”

Current developments of mixed conducting membranes on porous substrates

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Modified Ergun Equation for Airflow through Packed Bed of Loblolly Pine Grinds

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