Evaporation and Combustion of Suspended Droplets with Buoyancy-Driven Flows

Numerical models for droplet combustion typically assume spherical symmetry, simplifying the fluid dynamics in favor of a detailed description of the combustion chemistry. This study relaxes that hypothesis by presenting a comprehensive numerical framework that includes: i) interface-resolved evaporation; ii) surface tension effects; iii) complex gas-phase kinetics; iv) radiation. This model employs the volume-of-fluid approach for the description of the two-phase system, and it enables the description of deformable droplets, in motion or suspended on a solid fiber. Despite the increased computational time, this model can directly resolve multidimensional phenomena, such as buoyancy-driven flows, droplet deformation, liquid internal recirculation, and non-spherical flames. This research helps to improve our understanding of droplet combustion dynamics, and it can be used to correct predictions from simplified models, accounting for multidimensional fluid dynamics phenomena.