Water-Drive Recovery Efficiency - Craig Correlation Formula
Water-Drive Recovery Efficiency - Craig Correlation calculates water-drive recovery efficiency for waterflooding and eor workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (phi, S_w, B_oi, k, mu_wi, mu_oi, P_i, P_a) 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, E_R equals 55.507807 percent.
0.2
0.25
1.25
0.5
0.8
2
3000
2500
Inputs
phi
fractionPorosity
S_w
fractionWater Saturation
B_oi
RB/STBInitial Oil Formation Volume Factor
k
DPermeability
mu_wi
cPWater Viscosity
mu_oi
cPOil Viscosity
P_i
psiInitial Pressure
P_a
psiPressure at Depletion
Outputs
E_R
Water-Drive Recovery Efficiency
Source and review
reviewedThe Reservoir Engineering Aspects of Waterflooding, Craig Jr., F. F. (2004)
Craig Jr., F. F. 2004. The Reservoir Engineering Aspects of Waterflooding, Vol. 3. SPE Monograph Series, Page 83.
Source