McCain Saturated Water Compressibility with Gas Liberation Formula
McCain Saturated Water Compressibility with Gas Liberation calculates saturated water compressibility for fluid properties workflows in phase behavior and thermodynamics.
How engineers use this formula
Use this formula when the listed inputs (c_wunder, B_g, B_w, dRsw_dP) are known and the assumptions behind the cited fluid properties 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, c_wsat equals 0.000017 1/psi.
0.000003
0.005
1.02
0.00292729083645928
Inputs
c_wunder
1/psiUndersaturated Water Compressibility Term
B_g
rb/SCFGas Formation Volume Factor
B_w
rb/STBWater Formation Volume Factor
dRsw_dP
scf/STB/psiSolution Gas-Water Pressure Derivative
Outputs
c_wsat
Saturated Water Compressibility
c_wgas
Gas-Liberation Compressibility Term
c_wunder
Undersaturated Water Compressibility Term
B_g
Gas Formation Volume Factor
B_w
Water Formation Volume Factor
dRsw_dP
Solution Gas-Water Pressure Derivative
Source and review
reviewedFormation Water PVT Properties, McCain, W.D. Jr., Petroleum Office
McCain, W.D. Jr. 1991. Reservoir-Fluid Property Correlations-State of the Art; Petroleum Office Formation Water PVT Properties.
Source