Analysis and Prediction of Soot Morphology in Post-Detonation Fireballs

How soot evolves and disperses in detonation-like conditions is not well understood, despite the importance of soot morphology and dispersion on radiative and mass transport. To model soot formation and transport, a simulation framework was compiled using several different models to simulate the explosive flow and particle formation and development. For the flow, CTH, a Sandia hydrocode that has multi-material simulation capability, was used to model the detonation and early-time gas dynamics of a canonical hemispherical explosive charge. Subsequently, simulation is handed off to HyBurn, an in-house code at the University of Florida that excels at modeling instability growth [1], wherein later-time hydrodynamics are computed. In parallel, particle size distribution predictions are made by modeling coagulation and aggregation in Lagrangian-tracked parcels of fluid with the commercial code ANSYS Chemkin Pro. Custom collision kernels were also examined to observe the impact on particle agglomeration. Comparison to observation highlights persisting gaps in modeling particle coagulation.