Permeability Estimation Based on the Geometry of Pore Space via Random Walk on Grids

Table 1

Permeability, MPD, and factor estimated by WOG and Green’s function for voids of simple geometries.

Void shape	Reference length	Theoretical	MPD; ^¢	MPD; ^ǂ	^¢	^ǂ	^£
Parallel plane (Figure 2(a))	Plane distance		0.2763d	0.2714 d	1.091	1.131	∞
Square (Figure 2(b))	Side-length		0.1751d	0.1701 d	1.145	1.123	16
Circle (Figure 2(c))	Radius R		0.3318R	0.3235 R	1.135	1.194	4π
Ellipse (Figure 2(d))	Semiaxes: a, b		0.4210 b (as )	—	1.128	—	(15 as )
Equilateral triangle (Figure 2(e))	Side-length		0.1054 d	—	1.125	—

Theoretical is obtained according to pressure drops and theoretical flow rates in Drazin and Norman [25]. ^¢ is the MPD estimated by random walk on grid (WOG); . ^ǂ is the MPD evaluated by Green’s function by Equations (6), (8), and (10); . ^£φ according to Berger [24].