Skin factor due to partial penetration

Input(s)

$h_{t}$: Total Formation Thickness $(\mathrm{ft})$

rw: Radius of Wellbore (ft)

$k_{v}$: Vertical Permeability $(\mathrm{mD})$

$k_{h}$ : Horizontal Permeability $(\mathrm{mD})$

$h_{p}$ : Height of Perforated interval (ft)

$h_{a}$ : Height (ft)

$h_{p d}$ : Dimensionless Perforated Thickness (fraction)

$\mathrm{h}$ : Thickness of reservoir ( $\mathrm{ft}$ )

Output(s)

$r_{d}$: Permeability of altered zone $(\mathrm{mD})$

A: Dimensionless Constant A (dimensionless)

B: Dimensionless Constant B (dimensionless)

$s_{p}$ : Skin Factor from partial penetration (dimensionless)

Formula(s)

Reference(s)

Pressure Transient Testing, Lee, Rollins & Spivey, Page: 44.