Difference between revisions of "Gas/Oil Interfacial Tension"

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:<math> \sigma_{100} =37.5 - 0.2571 SG_{oAPI}</math>
 
:<math> \sigma_{100} =37.5 - 0.2571 SG_{oAPI}</math>
  
:<math> At\ T<68F,\  \sigma_o=\sigma_{68}</math>
+
:<math> At\ T<68F,\  \sigma_{od}=\sigma_{68}</math>
:<math> At\ 68F<T<100F,\  \sigma_o=\frac{\sigma_{68} + (T - 68) * (\sigma_{100} - \sigma_{68})}{ (100 - 68)}</math>
+
:<math> At\ 68F<T<100F,\  \sigma_{od}=\frac{\sigma_{68} + (T - 68) * (\sigma_{100} - \sigma_{68})}{ (100 - 68)}</math>
:<math>At\ T>100F,\ \sigma_o=\sigma_{100}</math>
+
:<math>At\ T>100F,\ \sigma_{od}=\sigma_{100}</math>
 +
 
 +
:<math> \sigma_{o}=\sigma_{od} \times (1-0.24P^0.45)</math>
 +
 
 +
 
 +
:<math> if (\sigma_{o}<1) \sigma_{o}=1</math>
 +
 
  
 
The density of formation water (brine) at reservoir conditions:
 
The density of formation water (brine) at reservoir conditions:

Revision as of 07:53, 5 October 2020

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_{od}=\sigma_{68}
 At\ 68F<T<100F,\  \sigma_{od}=\frac{\sigma_{68} + (T - 68) * (\sigma_{100} - \sigma_{68})}{ (100 - 68)}
At\ T>100F,\ \sigma_{od}=\sigma_{100}
 \sigma_{o}=\sigma_{od} \times (1-0.24P^0.45)


 if (\sigma_{o}<1) \sigma_{o}=1


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, lbm/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.