Reservoir EngineeringWaterflooding and EOR
Waterflood Oil Displacement Ratio from Average Saturation Formula
Waterflood Oil Displacement Ratio from Average Saturation calculates oil displacement ratio for waterflooding and eor workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (S_w, S_iw, f_s) are known and the assumptions behind the cited waterflooding and eor 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, Q_p equals 0.5 dimensionless.
S_wfraction
0.55
S_iwfraction
0.25
f_sfraction
0.4
Inputs
S_w
fractionAverage Water Saturation
S_iw
fractionInitial or Interstitial Water Saturation
f_s
fractionFraction of Total Flowing Stream
Outputs
Q_p
dimensionless
Oil Displacement Ratio
S_w
fraction
Average Water Saturation
S_iw
fraction
Initial or Interstitial Water Saturation
f_s
fraction
Fraction of Total Flowing Stream
Source and review
reviewedWillhite, G. P. Waterflooding, SPE Textbook Series Vol. 3, Chapter 3, Page 65.
Source