A computational study of thermally induced secondary atomization in multicomponent droplets

This study presents computational simulations of multicomponent and multiphase flows to reproduce the physical phenomena in secondary atomization a droplet induced by hot temperature environment. The fluid dynamics model is based on geometric volume method, with piecewise linear interface calculation reconstruction for accurate determination curvature evaporation fluxes at interface. purpose was faithfully complex processes, such as internal gas cavity formation, liquid–vapour instability, collapse liquid jet ejection, pinch-off droplet, leading microexplosion phenomenon that greatly enhances rate non-volatile droplets. solver validated against analytical solution benchmark cases, experimental data bicomponent droplets reported literature. developed used predict heavy fuel oil exposed high temperatures under microgravity conditions. Different regimes were identified, depending initial size bubbles. While small bubbles led simple ejections, caused larger produce formation. When ratio between bubble volumes bigger than 0.7, microexplosions occurred. results found be consistent cases burst flat surfaces, showing strong dependence Ohnesorge number ( $Oh$ ). Key observable quantities, particularly velocity cap drainage velocity, agree correlations other studies. similarities also supported studies extending over wide range (4000 cases) different . An inversion (above critical value $Oh_c$ ) observed.