(1)	$\begin{array}{l}\displaystyle k_{row}(s_o) = k_{rowc} \, \bigg[ \frac{ s_o - s_{orw} }{ 1- s_{wi} - s_{orw} } \bigg]^{n_{ow}}\end{array}$

(2)	$\begin{array}{l}\displaystyle k_{rwo}(s_w) = k_{rwoc} \, \bigg[ \frac{ s_w - s_{wco} }{ 1- s_{wco} - s_{orw} } \bigg]^{n_{wo}}\end{array}$

current oil saturation, $\begin{array}{l}s_o = 1 - s_w\end{array}$

current water saturation, $\begin{array}{l}s_w = 1 - s_o\end{array}$

residual oil saturation to water displacement, below which oil is immobile

critical water saturation to oil displacement, below which water is immobile

where $\begin{array}{l}s_{wi}\end{array}$ is initial water saturation which maybe equal to critical $\begin{array}{l}s_{wсo}\end{array}$ or less than critical $\begin{array}{l}s_{wi} < s_{wco}\end{array}$ like for example in petroleogenetic rocks.

The model assumes no gas presence in pores.

Fig. 1. Typical Oil+Water relative permeability

Page tree

See also