Pore-wall roughness as a fractal surface and theoretical simulation of mercury intrusion/retraction in porous media

Journal Article · Wed Sep 01 00:00:00 EDT 1993 · Journal of Colloid and Interface Science; (United States)

DOI:https://doi.org/10.1006/jcis.1993.1326· OSTI ID:6299657

Tsakiroglou, C D; Payatakes, A C ^[1]

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1. Univ. of Patras (Greece). Dept. of Chemical Engineering

The mercury intrusion/retraction curves of many types of porous materials (e.g., sandstones) have sections of finite slope in the region of high and very high pressure. This feature is attributed to the existence of microroughness on the pore walls. In the present work pore-wall roughness features are added to a three-dimensional primary network of chambers-and-throats using ideas of fractal geometry. The roughness of the throats is modeled with a finite number of self-similar triangular prisms of progressively smaller sizes. The roughness of the chambers is modeled in a similar way using right circular cones instead of prisms. Three parameters suffice for the complete characterization of the model of fractal roughness, namely, the number of features per unit length, the common angle of sharpness, and the number of layers (which is taken to be the same for throats and chambers). Analytical relations that give the surface area, pore volume, and mercury saturation of the pore network as functions of the fractal roughness parameters are developed for monolayer and multilayer arrangements. The chamber-and-throat network with fractal pore-wall roughness is used to develop an extended version of the computer-aided simulator of mercury porosimetry that has been reported in previous publications. This new simulator is used to investigate the effects of the roughness features on the form of mercury intrusion/retraction curves. It turns out that the fractal model of the porewall roughness gives an adequate representation of real porous media, and capillary pressure curves which are similar to the experimental ones for many typical porous materials such as sandstones. The method is demonstrated with the analysis of a Greek sandstone.

• OSTI ID: 6299657
• Journal Information: Journal of Colloid and Interface Science; (United States), Vol. 159:2; ISSN 0021-9797
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
58 GEOSCIENCES
POROSIMETERS
SIMULATORS
SANDSTONES
POROSITY
FRACTALS
MERCURY
PORE STRUCTURE
POROUS MATERIALS
ROUGHNESS
SURFACE AREA
THREE-DIMENSIONAL CALCULATIONS
WALLS
ANALOG SYSTEMS
ELEMENTS
FUNCTIONAL MODELS
MATERIALS
MEASURING INSTRUMENTS
METALS
MICROSTRUCTURE
ROCKS
SEDIMENTARY ROCKS
SURFACE PROPERTIES
360606* - Other Materials- Physical Properties- (1992-)
580000 - Geosciences