A strain dependent intrinsic permeability model.

The model was proposed in [44] and it was further investigated in [45] .

The model takes the form of

\[ \mathbf{k} =f(\epsilon_v) e^{b_1 {\bar\epsilon}^p}\mathbf{k}_0 \]

with

\[ f(\epsilon_v)= \begin{cases} 10^{b_2 \epsilon_v}, & \epsilon_v <=0\\ 10^{b_3 \epsilon_v}, & \epsilon_v >0 \end{cases} \]

where

\( \epsilon_v \)	the volumetric strain,
\( {\bar\epsilon}^p\)	the equivalent plastic strain,
\(\mathbf{k}_0\)	the initial intrinsic permeability,
\(b_1,\,b_2,\,b_3\)	the three parameters.

Note: In [44] and [45] , from the point of view of experiment of permeability change, the symbols of \( \Delta \epsilon_v \) and \(\Delta {\bar\epsilon}^p\) are used for \( \epsilon_v \) and \( {\bar\epsilon}^p\), respectively. That means that the symbols of \( \Delta \epsilon_v \) and \(\Delta {\bar\epsilon}^p\) refer to the increment of the volumetric strain and the increment of the equivalent plastic strain, respectively, from the beginning of the experiment.

Child parameters, attributes and cases

Additional info