Deliverability Equation for Shallow Gas Reservoirs Formula
Deliverability Equation for Shallow Gas Reservoirs calculates performance coefficient for well performance workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (k, h, T, mu_g, z, re, rw) 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, C equals 0.052256 dimensionless.
100
50
520
0.02
0.85
1000
0.3
Inputs
k
mDPermeability
h
ftReservoir Thickness
T
°RReservoir Temperature
mu_g
cPGas Viscosity
z
dimensionlessGas Compressibility Factor
re
ftDrainage Radius
rw
ftWellbore Radius
Outputs
C
Performance Coefficient
k
Permeability (rearranged)
h
Reservoir Thickness (rearranged)
T
Reservoir Temperature (rearranged)
mu_g
Gas Viscosity (rearranged)
z
Gas Compressibility Factor (rearranged)
re
Drainage Radius (rearranged)
rw
Wellbore Radius (rearranged)
Source and review
reviewedAhmed, T., McKinney, P.D. (2005). Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 3, Page: 287.
Source