Size distribution of daughter bubbles or drops resulting from binary breakup due to random initial deformation conditions
Predicting the interfacial area, and hence the size distribution of fluid particles in multiphase systems is essential as this parameter is fundamental in the design of reactors and apparatuses used in separation and purification technologies. This article presents a simplified model for the evolution of the shapes of fluid particles (bubbles or droplets) breaking in turbulent flow. The final size distribution of the daughter particles results from the application of initial conditions that reflect the random nature of turbulence.
The results suggest that the size distribution of the daughter particles is strongly influenced by the ability of the inner phase to move between parts of the particle. In the case of bubbles, the gas moves easily resulting in a ∪-shaped bubble size distribution. Conversely, in the case of droplets, the motion of the inner liquid is resisted by its higher inertia, resulting in a ∩-shaped droplet size distribution. Despite the simplified description of the particle shape and of the deformation rates, the present model allows to physically capture and explain the differences in particle size distribution resulting from the binary breakup of bubbles and droplets in turbulent flows.
The effect of the external flow is simulated through initial particle deformation into a dumbbell shape, initial deformation rates, and the Weber number. The time evolution of the particle shape is modeled by a set of Rayleigh-Plesset equations and the internal flow through the neck. The final daughter size distribution results from modeling of 106 particles of sizes ranging from 3 to 7 mm.
- Zednikova M.*, Stanovsky P., Orvalho S.: Size distribution of daughter bubbles or drops resulting from binary breakup due to random initial deformation conditions. Sep. Pur. Technol. 2025, 363, 132114. doi.org/10.1016/j.seppur.2025.132114