Interfacial tension and centrifugal forces balanced at mechanical equilibrium.

centrifugal-IFT equilibrium

centrifugal-IFT equilibrium

Interfacial tension of any liquid that gives a shape very close to a cylinder at the equilibrium point, can be estimated using Vonnegut’s expression:

\sigma=\frac{\Delta\rho\omega^2}{4}R^3

ω : angular velocity; (radians per second, degrees per second, revolutions per second)

Δρ : difference between two fluid: the less-dense and the dense