Mercury porosimetric approach on the validity of Darcy's law in the axial penetration of wood

Abstract

The permeability of low permeable wood deviates from Darcy's law with the length of the speciment used. This paper links this phenomenon with the porous structure of wood. The mercury porosimetric measurements have shown that our characteristic pore sizes r change with the length L of the specimen in the same manner as it has been found by permeability measurements for the conducting area within the wood. A comparison of the relative permeabilities of different woods by mercury porosimetry is therefore possible only when r(L) respectively ln r(L) can be determined. This requires the measurements of at least two series of samples of different length.