Effective compressibility in undersaturated oil reservoirs - Hawkins

Input(s)

$\mathrm{S}_{\mathrm{oi}}$: Initial Oil Saturation (fraction)

$\mathrm{S}_{\mathrm{wi}}$: Initial Water Saturation (fraction)

$\mathrm{c}_{\mathrm{o}}$: Oil Compressibility $(1 / \mathrm{psi})$

$\mathrm{c}_{\mathrm{w}}$: Water Compressibility $(1 / \mathrm{psi})$

$\mathrm{c}_{\mathrm{f}}$: Formation Compressibility $(1 / \mathrm{psi})$

Output(s)

$\mathrm{c}_{\mathrm{e}}$: Effective Compressibility (1/psi)

Formula(s)

$$ \mathrm{c}_{\mathrm{e}}=\frac{\mathrm{S}_{\mathrm{oi}} * \mathrm{c}_{\mathrm{o}}+\mathrm{S}_{\mathrm{wi}} * \mathrm{c}_{\mathrm{w}}+\mathrm{c}_{\mathrm{f}}}{1-\mathrm{S}_{\mathrm{wi}}} $$

Reference(s)

Ahmed, T., McKinney, P.D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 5, Page: 334 .