PetrophysicsRock Properties

Apparent Interfacial Tension - de Nouy Ring Method Formula

S=\frac{mg}{2l}

Apparent Interfacial Tension - de Nouy Ring Method calculates apparent interfacial tension for rock properties workflows in petrophysics.

Calculate

How engineers use this formula

Use this formula when the listed inputs (m, g_accel, l_ring) are known and the assumptions behind the cited rock 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, S_app equals 9.8 dyn/cm.

0.1

g_accelcm/s^2

980

l_ringcm

Inputs

m

Measured Ring Pull Mass

g_accel

cm/s^2

Acceleration of Gravity

l_ring

Ring Perimeter

Outputs

S_app

dyn/cm

Apparent Interfacial Tension

m

Measured Ring Pull Mass

g_accel

cm/s^2

Acceleration of Gravity

l_ring

Ring Perimeter

Source and review

reviewed

Petroleum and Natural Gas Laboratory Course Notes, I-Fluid Properties, Mihcakan, I. M., Alkan, K. H., Ugur, Z. (2001)

Mihcakan, I. M., Alkan, K. H., and Ugur, Z. 2001. Petroleum and Natural Gas Laboratory Course Notes, I-Fluid Properties, ITU Petroleum and Natural Gas Engineering, Page 4-3.

Source