Self-similar rupture of thin free films of power-law fluids.

The rupture of a thin free film of a power-law fluid under the competing influences of destabilizing van der Waals pressure and stabilizing surface tension pressure is analyzed. In such a fluid, viscosity decreases with the deformation rate raised to the n-1 power where 0<n≤1 (n=1 for a Newtonian fluid). When 6/7<n≤1, film rupture occurs under a balance between van der Waals pressure, inertial stress, and viscous stress. When n<6/7, however, the dominant balance changes: Viscous stress becomes negligible and the film ruptures under the competition between van der Waals pressure, inertial stress, and surface tension pressure.