  Within the framework of fuel cells, porous materials are used for filtration
purpose. Determining physical properties like porosity and permeability are of
utmost importance to predict and to manage filtration efficiency of the
materials. The permeability of materials is often determined experimentally in
laboratory with disc samples (outlet of the flow is achieved through the porous
material) that are not exactly similar to the tubes which are used in realistic
operating conditions (a main flow is found additionally to the one through the
material). Thus, the effect of a second outlet on the Darcian's permeability
characterization bench should be studied. In the present paper, we present a
new test bench to determine experimentally the Darcy's and Forchheimer's
permeabilities for a porous media by taking into account two outlets. Operating
parameters (temperature, pressure and mass flow rate) are measured for three
different configurations: i) secondary outlet (S.O) is 0% open, ii) S.O is 50%
open and iii) S.O is 100% open. Then Darcy's and Forchheimer's permeability for
all these three cases are compared and discussed in details. It has been found
that the secondary outlet opening does not affect the Darcian's permeability
but have substantial influence on the Forchheimer's one through the
modifications of the range of study (lower mass flow rate penetrates the porous
medium).
