Analysis of DST flow data with Ramey type curves
Input(s)
\(\mathrm{p}_{\mathrm{i}}\): Initial Pressure \((\mathrm{psi})\)
\(\mathrm{p}_{\mathrm{wf}}\): Well Flowing Pressure (psi)
\(\mathrm{p}_{\mathrm{o}}\): Pressure at Time \(T=0\) (psi)
Ø: Porosity (dimensionless)
\(c_{\mathrm{t}}\): Total Compressibility \((1 / \mathrm{psi})\)
\(\mathrm{h}\): Formation Thickness (ft)
C: Wellbore Storage Coefficient (bbl/psi)
\(r_{w}\): Radius of Wellbore \((\mathrm{ft})\)
\(\mu\): Viscosity \((\mathrm{cP})\)
\(\mathrm{t}_{\mathrm{c}}\): Dimensionless Parameter from Curve Fitting as \(\frac{T_{d}}{c_{d}}\) (dimensionless)
\(\mathrm{t}\): Time (h)
CES: Match Point for Dimensionless Well Bore Coefficient from Curve as (Cd E (2 s))_(mp) (dimensionless)
Output(s)
\(\mathrm{p}_{\mathrm{DR}}\): Dimensionless Pressure (dimensionless)
\(\mathrm{q}_{\mathrm{DR}}\): Dimensionless Flow Rate (dimensionless)
\(\mathrm{C}_{\mathrm{D}}\): Dimensionless Well Bore Storage Coefficient (dimensionless)
\(\mathrm{k}\): Permeability \((\mathrm{mD})\)
s: Skin Factor (dimensionless)
Formula(s)
Reference(s)
Lee, J., Rollins, J. B., & Spivey, J. P. (2003). Pressure Transient Testing (Vol. 9). Richardson, Texas: Society of Petroleum Engineers, Page: 155.