Wet In-Situ Combustion Oil Production - Nelson and McNeil Formula
Wet In-Situ Combustion Oil Production - Nelson and McNeil calculates cumulative oil production for waterflooding and eor workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (V_r, phi, S_i, S_f, V_s, S_r, h_n, h_t, E_fire) 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, N_p equals 72,770.04 bbl.
100
0.25
0.65
0.25
60
0.2
40
50
0.7
Inputs
V_r
acre-ftVolume of Burned Reservoir
phi
fractionPorosity
S_i
fractionInitial Oil Saturation
S_f
fractionOil Saturation After Fire Flood
V_s
acre-ftVolume Swept by Steam
S_r
fractionResidual Oil Saturation
h_n
ftNet Reservoir Thickness
h_t
ftTotal Reservoir Thickness
E_fire
fractionFire Flood Efficiency
Outputs
N_p
Cumulative Oil Production
phi
Porosity
E_fire
Fire Flood Efficiency
h_n
Net Reservoir Thickness
h_t
Total Reservoir Thickness
V_s
Volume Swept by Steam
V_r
Volume of Burned Reservoir
S_f
Oil Saturation After Fire Flood
S_r
Residual Oil Saturation
Source and review
reviewedEnhanced Oil Recovery, Green, D.W., Willhite, G.P.
Green, D.W. and Willhite, G.P. Enhanced Oil Recovery, Page 395.