Skin factor by Hawkins method

Input(s)

$\mathrm{k}$: Permeability of Reservoir $(\mathrm{mD})$

$k_{s}$ : Permeability of Skin Zone Near Wellbore (mD)

$r_{w}$: Radius of Wellbore (ft)

$r_{s}$: Radius of Skin Zone $(\mathrm{ft})$

Output(s)

S: Skin Factor (dimensionless)

Formula(s)

$$ S=\left(\left(\frac{k}{k_{s}}\right)-1\right) * \ln \left(\frac{r_{s}}{r_{w}}\right) $$

Reference(s)

Ahmed, T., McKinney, P.D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 1, Page: 37.