Nonlinear stability of a heated thin liquid film with variable viscosity

The stability of a heated liquid film subjected to surface tension and van der Waals forces is explored in the case where the fluid viscosity is temperature dependent. The limits of very large and very small Biot numbers are examined, and in these cases it is found that the evolution equation can be rescaled to return the model equation developed by Williams and Davis [J. Colloid Interface Sci. 90, 220 (1982)] for an isothermal film. The effect of variable viscosity is deduced and is found to reduce the rupture time of the film relative to the constant‐viscosity result.