Generalized Reservoir Gas Flow Deliverability Formula
Generalized Reservoir Gas Flow Deliverability calculates reservoir gas flow rate for well performance workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (C_perf, p_bar, P_wf, n_perf) are known and the assumptions behind the cited well performance relationship match the engineering case being checked.
Assumptions
- Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
- The declared units match the field-unit constants used in the formula.
- The cited formula applies to the selected petroleum engineering workflow.
Limitations
- The calculation does not replace a full engineering model or operating procedure.
- Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.
Common mistakes
- Mixing unit systems without converting the inputs.
- Using default example values as field recommendations.
- Applying the formula outside the source assumptions.
Default example
Using the default inputs, W equals 3.82541 bbl/d.
0.00002
2500
1500
0.8
Inputs
C_perf
bbl/d/psi^(2n)Performance Coefficient
p_bar
psiMean Formation Pressure
P_wf
psiBottomhole Flowing Pressure
n_perf
dimensionlessPerformance Exponent
Outputs
W
Reservoir Gas Flow Rate
C_perf
Performance Coefficient
p_bar
Mean Formation Pressure
P_wf
Bottomhole Flowing Pressure
n_perf
Performance Exponent
Source and review
reviewedReservoir Engineering Assessment of Geothermal Systems, Ramey Jr., H.J. (1981)
Ramey Jr., H.J. 1981. Reservoir Engineering Assessment of Geothermal Systems, Department of Petroleum Engineering, Stanford University, Page 8.8.
Source