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5.4 Results
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Figure (5.9), as columns with the dark color. Figure (5.10b) shows the scatter
diagram of velocities in the MDPN. It is clear that in MDPN, velocities in
different directions are comparable and there is no strongly dominant direction.
This shows that, using the MDPN model one can get more realistic velocity
fields.
Figure 5.9: Average velocities in the three principal directions of a regular
network model (white columns), and in the 13 directions of MDPN Model (dark
columns). Direction number 1 is parallel to the overall flow (or pressure gradient)
direction, and directions number 2 and 3 are perfectly perpendicular to the
flow direction. The other directions are oblique with respect to the overall flow
direction (Figure 2.1).
5.4.2 Calculation of relative permeabilities using MDPN
model
We have chosen five different networks to study the effect of conductance
of drained pore bodies on the network permeability. The first three are the
generic network models (R 1 , R 2 , and R 3 ) whose properties were presented in
Section 5.2. The other two networks were designed on the basis of properties
of two real porous media: a carbonate rock [Al-Kharusi and Blunt, 2008] and
a Fontainebleau sandstone [Lindquist et al., 2000]. The reason for choosing
these two porous media is their different topology; Fontainebleau sandstone
has a wide range of coordination numbers with a mean coordination number
of around 3.5, while the carbonate rock has a much larger mean coordination
number of 8.0.
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