Surface tension

A3.5.1 Gas-Water#

Sutton

The Sutton correlation is a modern method for calculating interfacial tension between natural gas and water, accounting for the effects of pressure, temperature, and water salinity. Unlike classical approaches, this correlation was specifically developed for high-pressure and wide-temperature conditions, making it especially useful for deep-water fields and unconventional reservoirs. 
Recommended applicability range:

• CO ₂ content: < 15%
• Water salinity: 0 – 300,000 ppm
• Temperature: 100 – 400 °F
• Pressure: < 30,000 psi (optimal: 500 – 15,000 psi)

A3.5.2 Gas-Oil#

Abdul-Majid

The Abdul-Majid correlation is a specialized method for calculating interfacial tension between oil and natural gas, taking into account oil density, temperature, pressure, and gas properties. The method is based on experimental data from Middle Eastern oils. It demonstrates particular accuracy for light and medium oils under high-pressure conditions. 
Recommended applicability range:

• Oil density (API Gravity): 25 – 45 °API
• Gas–oil ratio: 200 – 2500 SCF/STB
• Temperature: 100 – 300 °F
• Pressure: < 10,000 psi (optimal: 1,000 – 8,000 psi)