Productivity index for a gas well

Input(s)

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

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

$\mathrm{T}$: Temperature $\left({ }^{\circ} \mathrm{R}\right)$

A: Drainage Area $\left(\mathrm{ft}^{2}\right)$ )

$\mathrm{C}_{\mathrm{A}}$: Shape Factor (dimensionless)

$\mathrm{r}_{\mathrm{w}}$: Wellbore Radius (ft)

S: Skin (dimensionless)

Output(s)

J: Productivity Index (MSCF/day/psi ${ }^{2} / \mathrm{cP}$ )

Formula(s)

$$ \mathrm{J}=\frac{\mathrm{k} * \mathrm{~h}}{1422 * \mathrm{~T} *\left(0.5 * \ln \left(\frac{4 * \mathrm{~A}}{1.781 * \mathrm{C}_{\mathrm{A}} * \mathrm{r}_{\mathrm{w}}^{2}}\right)+\mathrm{S}\right)} $$

Reference(s)

Ahmed, T., McKinney, P.D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 3, Page: 188 .