Reservoir EngineeringPressure Transient Analysis
Dimensionless Pressure - Radial Flow Constant-Pressure Production Formula
Dimensionless Pressure - Radial Flow Constant-Pressure Production calculates dimensionless pressure for pressure transient analysis workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (P_i, P, P_wf) are known and the assumptions behind the cited pressure transient analysis 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, P_d equals 0.5 dimensionless.
P_ipsi
4000
Ppsi
3500
P_wfpsi
3000
Inputs
P_i
psiInitial Reservoir Pressure
P
psiFinal Reservoir Pressure
P_wf
psiWell Flowing Pressure
Outputs
P_d
dimensionless
Dimensionless Pressure
P_i
psi
Initial Reservoir Pressure
P
psi
Final Reservoir Pressure
P_wf
psi
Well Flowing Pressure
Source and review
reviewedLee, J., Rollins, J.B. and Spivey, J.P. 2003. Pressure Transient Testing, SPE Textbook Series Vol. 9, Page 9.
Source