One possible culprit in the prediction of overly fine droplet sizes is that the film stripping model by default uses a fixed strain criterion to determine when droplets will break from the film. There is a better way to define the stripping criterion but it is still a hidden feature in Fluent . This new criterion is based on the Stripping Weber Number. To get better stripping results, it is advised to use this Weber number-based stripping criterion. To use it, you need to set a wall film model parameter. Test its current value using: (get-film-parameter ‘stripping-criterion) It is likely still set to the default value of 0. Now set it to 1 (set-film-parameter ‘stripping-criterion 1) and change the value for Critical Shear to around 0.06. (the Critical Shear parameter will now function as a Critical Weber number but its name in the TUI, and its units are unchanged) This usually gives more realistic results. If you see too much stripping you can increase Critical Shear it to say 0.1. If no stripping occurs, reduce it to 0.05, 0.04 etc.