To solve for permeability, an arbitrary value of permeability is assumed (0.1 md is often a good first estimate), and Equation 2 is solved for ''r''<sub>d</sub>. Then, this value for ''r''<sub>d</sub> is used in Equation 3 to solve for permeability. For each iteration after the first, use the permeability calculated from Equation 3 in solving for ''r''<sub>d</sub> from Equation 2; this procedure usually converges in three to four iterations. | To solve for permeability, an arbitrary value of permeability is assumed (0.1 md is often a good first estimate), and Equation 2 is solved for ''r''<sub>d</sub>. Then, this value for ''r''<sub>d</sub> is used in Equation 3 to solve for permeability. For each iteration after the first, use the permeability calculated from Equation 3 in solving for ''r''<sub>d</sub> from Equation 2; this procedure usually converges in three to four iterations. |