  The thin runback water films driven by the gas flow, the pressure gradient
and the gravity on the iced aircraft surface are investigated in this paper. A
three-dimensional film flow model based on Finite Volume Method (FVM) and the
lubrication theory is proposed to describe the flow. The depth-averaged
velocity of the film is stored in Cartesian coordinates to avoid the appearance
of the metric tensors. The governing equations are discretized in the first
layer structured grid cell which is selected as the grids for film flow. In
order to verify this method, comparisons between numerical results and
experimental results of ice shapes on NACA 0012 airfoil and GLC-305 swept wing
are presented, both showing a good agreement for rime and glaze ice condition.
Overall, this model shows great potential to model ice accretion reasonably
under different icing conditions. Besides, the present method doesn't require
analytic metric terms, and can be easily coupled to existing finite volume
solvers for logically Cartesian meshes.
