Equivalent Water Saturation in Burned Zone - Nelson Formula
Equivalent Water Saturation in Burned Zone - Nelson calculates equivalent water saturation in burned zone for waterflooding and eor workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (x_HC, a_r, phi, m_CO) 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, S_wF equals 0.002096 fraction.
0.34
0.02
0.25
0.1
Inputs
x_HC
dimensionlessEquivalent Atomic Hydrogen-to-Carbon Ratio of Fuel
a_r
Mscf/ft^3Air Requirement to Burn Reservoir Rock
phi
fractionPorosity
m_CO
fractionCarbon Monoxide to Carbon Oxides Ratio
Outputs
S_wF
Equivalent Water Saturation in Burned Zone
a_r
Air Requirement to Burn Reservoir Rock
phi
Porosity
m_CO
Carbon Monoxide to Carbon Oxides Ratio
Source and review
reviewedThermal Recovery, Prats, M. (1986)
Prats, M. 1986. Thermal Recovery. Society of Petroleum Engineers, Chapter 8, Page 92.
Source