Observed non-linearity of Darcy-permeability in compacted fine pigment structures

摘要: Abstract Liquid permeability was measured on a range of porous samples, using specially-constructed high pressure permeation cell. The samples consisted compacted fine isotropic mineral pigment—calcium carbonate—compressed over compaction pressures. These have pore diameters typically (number basis) finer than 0.1 μm. porosities and the size distributions been determined by means mercury porosimetry. these fine-pore network systems is seen under certain conditions not to obey well-known linearity Darcy relation as function applied liquid differential. A considerable pressure–flux hysteresis observed following saturation imbibition. Furthermore, it that there no direct linear correlation between porosity despite use constant pigment particle distribution and, hence, skeletal distribution. displays local maximum at fractional approximately 0.26 with further distinct drop around 0.27. Interestingly, this phenomenon also confirmed computer-based simulator which provides relative based matching percolation data. Taking into account effects earlier-proposed mechanisms preferred pathway flow film during imbibition, postulated some pores remain unfilled imbibition prior study, such remains entrapped air or vapour phase in microscopic ganglia. This does dissolve aliphatic oil used experiments. Structures delineated pore-throat structure will probably lead generally non-linear phenomena within dimensions studied here, can implications, amongst others, for filtration, catalysis absorption phenomena.