Pseudo-skin factor due to partial penetration (Odeh correlation)

Input(s)

$h_{1}$: Distance from payzone top to top of open interval (ft)

$h_{p}$ : Perforation interval (ft)

$\mathrm{h}$ : Total pay thickness $(\mathrm{ft})$

$r_{w}$ : Wellbore Dia (ft)

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

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

Output(s)

$z_{m}$: Well Perforation Distance $(\mathrm{ft})$

$h_{d}$ : Dimensionless Payzone Thickness (dimensionless)

b: Penetration Ratio (dimensionless)

$r_{w c}$ : Effective Wellbore dia (ft)

$s_{p}$ : Skin due to partial penetration (dimensionless)

Formula(s)

$$ \begin{gathered} z_{m}=\frac{h_{p}}{h} \\ h_{d}=\frac{h}{r_{w}} * \operatorname{sqrt}\left(\frac{k_{h}}{k_{v}}\right) \\ b=h_{1}+\frac{h_{p}}{2} \\ r_{w c}=r_{w} * 2.71^{0.2126} *\left(2.753+\frac{z_{m}}{h}\right) \\ s_{p}=1.35 *\left(\frac{1}{b}-1\right)^{0.825} *\left(\ln \left(r_{w} * h_{d}+7\right)-1.95-\ln \left(r_{\{w c\}}\right) *\left(0.49+0.1 * \ln \left(r_{w} * h_{d}\right)\right)\right) \end{gathered} $$

Reference(s)

Horizontal Well Technology, Joshi, Page: 495.