Page 487 - Petrophysics

TURBULENT FLOW OF GAS 455

0.01 0.1 1 10 100 1000
k, Mlllida~y
Figure 7.9. Correlation of p with K and f.

Figure 7.9 also shows a correlation of P with porosity and permeability
for carbonate and sandstone reservoirs. A reasonable estimation of the
non-Darcy flow coefficient, P (ft-'), can be obtained from the following
equation [34] :

4.85 x io4
P= (7.116b)
05.5 Ji;

where: k = average permeability, mD.
4 = porosity, fraction.

Using experimental flow data on consolidated and unconsolidated sand-
stone, carbonate, and dolomite core samples, Liu and Civan obtained
a correlation of p (K') with respect to permeability (mD), porosity
(fraction), and tortuosity z [38] :

8.91 x 108z
P= (7.116~)
4k