Variable thickness model for fluid films under large displacement.

We propose dynamic nonlinear equations for free thin fluid films. The obtained numerical solutions display a number of features consistent with recent experiments with fluid films under large deformations. In particular, we observe dynamic thickening. Our analysis is based on a two-dimensional model. The film's thickness is represented by the two-dimensional density ρ. We show that a broad range of effects can be captured by a proper internal energy function e(ρ).