Gas Deliverability Pressure-Squared Drawdown Calculator
Enter the required inputs, confirm the units, and run the calculator to solve delta_p2. Review the formula source and assumptions before using the result in engineering work.
Calculation context and source notes
Gas Deliverability Pressure-Squared Drawdown calculates pressure-squared drawdown for inflow performance workflows in production engineering. The page keeps the declared variables, units, source relationship, and output definition visible for technical review.
Use this formula when the listed inputs (P_r, P_wf) are known and the assumptions behind the cited inflow performance relationship match the engineering case being checked.
Solves for
delta_p2 (psi^2)
Best next page
Formula, variables, and sourceFormula, variables, and default calculation
Reproducible default result
With the default values shown below, the calculation returns delta_p2 = 6,750,000 psi^2. Defaults demonstrate the implementation; they are not recommended field values.
3000
1500
Input definitions
P_r
psiaAverage Reservoir Pressure
P_wf
psiaFlowing Bottom-Hole Pressure
Output definitions
delta_p2
Pressure-Squared Drawdown
P_r
Average Reservoir Pressure
P_wf
Flowing Bottom-Hole Pressure
Engineering use, assumptions, and limits
Use this formula when the listed inputs (P_r, P_wf) are known and the assumptions behind the cited inflow 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.
Frequently asked questions
What inputs does the Gas Deliverability Pressure-Squared Drawdown calculator need?
The calculation uses Average Reservoir Pressure (P_r), Flowing Bottom-Hole Pressure (P_wf). Enter values on the units shown beside each field.
What result does this calculator return?
The primary result is pressure-squared drawdown in psi^2. The formula section shows the declared relationship, variables, and a reproducible default calculation.
What should I check before using the result?
Confirm the unit basis, source applicability, and input quality. The calculation does not replace a full engineering model or operating procedure. Mixing unit systems without converting the inputs.
Source and record status
Source metadata identifies the relationship implemented by the calculator. Check the cited edition, unit basis, and scope against the engineering case before operational use.
Johnston and Lee, SPE 23440. Rawlins-Schellhardt pressure-squared gas deliverability method.
Open source reference