<p>A comprehensive icing prediction framework has been developed, including an airflow model, a droplet impingement model, a water film and ice accretion model, and a grid-regeneration tool. To accurately predict the runback water film and ice accretion, a new water film icing model is developed based on the finite-area method (FAM). After validation with experimental data, the framework has been applied to analyze the water film behavior and icing process on turbofan engine nacelle during aircraft takeoff phases. The effects of liquid water content (LWC) distribution, the water collection coefficient, the ice thickness, the freezing fraction, and the water film movement throughout continuous icing processes are discussed in detail. The conclusions demonstrate that ice accretion on the nacelle surface contributes to aerodynamic degradation, and alters subsequent water film dynamics, thereby impacting ice formation and aerodynamic performance. The icing prediction framework established in this study is proven to be an effective way for engine icing analysis.</p>