A detailed model for secondary atomization of liquid droplets by aerodynamic forces is presented. As an empirical extension of dynamic droplet deformation models, it accounts for temporal variations of the relative velocity between droplet and gas phase during the deformation and breakup process and describes the characteristic features of different breakup mechanisms (deformation kinetics, aerodynamics and product properties). Computed droplet trajectories and Sauter mean diameters have been compared using the proposed deformation-based model and a model using a breakup criterion based on the local instantaneous Weber number. It is concluded, that a deformation-based criterion should be used for droplets exposed to complex aerodynamic loading and that more experimental research is required to identify the accuracy of the presented detailed breakup product model. |