Production EngineeringWell Performance
Productivity Ratio Formula
Productivity Ratio calculates productivity ratio for well performance workflows in production engineering.
How engineers use this formula
Use this formula when the listed inputs (J, J_sw) 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, PR equals 1.2 fraction.
JSTB/day/psi
1.2
J_swSTB/day/psi
1
Inputs
J
STB/day/psiProductivity Index of the Well
J_sw
STB/day/psiProductivity Index of a Standard Well
Outputs
PR
fraction
Productivity Ratio
J
STB/day/psi
Productivity Index of the Well
J_sw
STB/day/psi
Productivity Index of a Standard Well
Source and review
reviewedJoshi, S.D. Horizontal Well Technology, Page 46.
SourceRelated formulas and calculators
Effective Wellbore Radius of a Well in Presence of Uniform Flux Fractures
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Effective Wellbore Radius of a Horizontal Well – Method 1 (Anisotropic Reservoirs)
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Effective Wellbore Radius of a Horizontal Well – van der Vlis et al. Method
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