We propose a computationally tractable model for film formation and breakup based on data from experiments and direct numerical simulations. This work is a natural continuation of previous studies where primary atomization is modeled based on local flow information from a relatively low-resolution tracking of the liquid interface [1]. Sub-models for film formation are supported by direct numerical simulations obtained with the Refined Level Set Grid (RLSG) method [2]. The overall approach is validated by a carefully designed experiment [3], where the liquid jet is cross flow-atomized in a rectangular channel so that a film forms on the wall opposite to the injection orifice. The film eventually breaks up at the downstream exit of the channel. Comparisons with Phase Doppler Particle Analyzer (PDPA) data and with non-intrusive film thickness point measurements complete this study.