Gas/Oil Interfacial Tension

Gas/Oil Interfacial Tension

Gas/Oil Interfacial Tension correlation was published by Baker and Swerdloff in 1956.

File:Gas/Oil Interfacial Tension.png

Gas/Oil Interfacial Tension correlation in the PVT software at pengtools.com

Math and Physics

$\sigma_{68} =39 - 0.2571 SG_{oAPI}$

$\sigma_{100} =37.5 - 0.2571 SG_{oAPI}$

$At\ T<68F,\ \sigma_o=\sigma_{68}$

$68F<T<100F,\ \sigma_o=\frac{\sigma_{68} + (T - 68) * (\sigma_{100} - \sigma_{68})}{ (100 - 68)}$

$< T>100F,\ sigma_o=\sigma_{100}$

The density of formation water (brine) at reservoir conditions:

$\rho_{wR}=\rho_{wSC}/B_w$

Nomenclature

$B_w$ = water formation volume factor, res bbl/STB

$C_{mg/l}$ = water salinity or solids concentration, mg/l

$\rho_{wSC}$ = water density at standard conditions, lb_m/ft³

References

Baker, O. and Swerdloff, W. 1955. Calculation of Surface Tension 3—Calculating parachor Values. Oil Gas J. (5 December 1955): 141. Baker, O. and Swerdloff, W. 1956. Calculation of Surface Tension 6—Finding Surface Tension of Hydrocarbon Liquids. Oil Gas J. (2 January 1956): 125.