Volume-Of-Fluid Simulations of Droplet Combustion

This work presents a comprehensive multiphase CFD framework which allows simulations of droplet evaporation and combustion problems, without assuming spherical symmetry. The model resolves the full multidimensional set of transport equations on mass, momentum, chemical species, and the temperature of the system. The gas-liquid interface is transported using the Volume-Of-Fluid approach, while the chemical reactions and gas-phase radiation are included using a direct-integration technique. The model’s validation confirms its accuracy in predicting the burning rates of droplets in microgravity conditions. More complex test cases, including the effect of normal gravity, are used to quantify the error of the spherical symmetry, especially at high Grashof numbers. Lastly, the multicomponent phase change model is exploited to resolve the droplet extinction due to water absorption effects.