Dimensionless time (radial flow/constant rate production)
Input(s)
\(\mathrm{t}\): Production Time \((\mathrm{h})\)
k: Permeability \((\mathrm{mD})\)
\(\emptyset\): Porosity (fraction)
\(c_{t}\): Total Compressibility \((1 / \mathrm{psi})\)
\(\mu\): Oil Viscosity \((\mathrm{cP})\)
\(r_{w}\): Wellbore Radius \((\mathrm{ft})\)
Output(s)
\(t_{d}\): Dimensionless Time (dimensionless)
Formula(s)
\[
t_{d}=\frac{0.0002637 * k * t}{\phi * \mu * c_{t} * r_{w}^{2}}
\]
Reference(s)
Lee, J., Rollins, J. B., & Spivey, J. P. (2003). Pressure Transient Testing (Vol. 9). Richardson, Texas: Society of Petroleum Engineers, Page: 8.