Dimensionless Pressure for Linear Flow Constant Rate General Case Calculator
Enter the required inputs, confirm the units, and run the calculator to solve p_D. Review the formula source and assumptions before using the result in engineering work.
Calculation context and source notes
Dimensionless Pressure for Linear Flow Constant Rate General Case calculates dimensionless linear flow pressure for pressure transient analysis workflows in reservoir engineering. The page keeps the declared variables, units, source relationship, and output definition visible for technical review.
Use this formula when the listed inputs (k, A, p_i, p, q, B, mu) are known and the assumptions behind the cited pressure transient analysis relationship match the engineering case being checked.
Solves for
p_D (dimensionless)
Best next page
Formula, variables, and sourceFormula, variables, and default calculation
Reproducible default result
With the default values shown below, the calculation returns p_D = 62.210373 dimensionless. Defaults demonstrate the implementation; they are not recommended field values.
50
100000
4000
3500
500
1.2
1.5
Input definitions
k
mDEffective Permeability
A
ft^2Drainage Area
p_i
psiInitial Reservoir Pressure
p
psiPressure at Time of Interest
q
STB/dayLiquid Flow Rate
B
rb/STBFormation Volume Factor
mu
cPFluid Viscosity
Output definitions
p_D
Dimensionless Linear Flow Pressure
k
Effective Permeability
A
Drainage Area
p_i
Initial Reservoir Pressure
p
Pressure at Time of Interest
q
Liquid Flow Rate
B
Formation Volume Factor
mu
Fluid Viscosity
Engineering use, assumptions, and limits
Use this formula when the listed inputs (k, A, p_i, p, q, B, mu) 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.
Frequently asked questions
What inputs does the Dimensionless Pressure for Linear Flow Constant Rate General Case calculator need?
The calculation uses Effective Permeability (k), Drainage Area (A), Initial Reservoir Pressure (p_i), Pressure at Time of Interest (p), Liquid Flow Rate (q), Formation Volume Factor (B), Fluid Viscosity (mu). Enter values on the units shown beside each field.
What result does this calculator return?
The primary result is dimensionless linear flow pressure in dimensionless. 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.
Lee, Rollins and Spivey, Pressure Transient Testing, SPE Textbook Series Vol. 9, linear-flow constant-rate dimensionless variables.
Open source reference