Dimensionless wellbore storage coefficient (compressible fluids for pressure build-up test)

Input(s)

C: Well Bore Storage Coefficient (bbl/psi)

$\emptyset$: Porosity (fraction)

$c_{f}$: Formation Compressibility (1/psi)

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

$r_{w}$: Well Bore Radius (ft)

Output(s)

$\mathrm{C}_{\mathrm{d}}$: Dimensionless Wellbore Storage Coefficient (dimensionless)

Formula(s)

$$ C_{d}=\frac{0.8936 * C}{\emptyset * c_{f} * h * r_{w}^{2}} $$

Reference(s)

Lee, J., Rollins, J. B., \& Spivey, J. P. (2003). Pressure Transient Testing (Vol. 9). Richardson, Texas: Society of Petroleum Engineers, Page: 105.