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The Dance of Drops in Homogeneous Isotropic Turbulence

Author: Alessio Roccon
(Polytechnic Department of Engineering and Architecture, University of Udine)

The breakage of drops in turbulence is a fundamental process governing phenomena ranging from fuel atomization in combustors to ocean spray formation. This visualization reveals the rich physics of drop breakage: turbulent stresses initiate a cascade of fragmentation events, generating droplets across a wide range of sizes and shapes, along with transient thin liquid films and filamentary threads.

[1] A. Roccon, F. Zonta, A. Soldati, Phase-field modeling of complex interface dynamics in dropladen turbulence, Phys. Rev. Fluids 8 (9), 090501
[2] A. Roccon, L. Enzenberger, D Zaza, A Soldati, MHIT36: A phase-field code for GPU simulations of multiphase homogeneous isotropic turbulence, Comp. Phys. Comm. 316 (109804)

Scientific Abstract:

We numerically investigate the breakage of liquid drops in homogeneous isotropic turbulence, a fundamental process central to diverse applications from fuel atomization to ocean spray formation. This problem involves rich physics, where interfacial phenomena (surface tension) interacts with the underlying turbulent flow [1]. We address these dynamics via direct numerical simulations coupled with a phase-field method. The simulations employ our recently developed GPU-accelerated opensource code [2], which enables the acquisition of high-fidelity spatial and temporal data by leveraging the Leonardo supercomputer. Visualization of the results highlights the complexity of drop–turbulence interactions, revealing the coexistence of distinct breakup modes. One mode originates from the formation of liquid films that progressively thin until puncture occurs. Another is associated with the development of elongated liquid threads that undergo pinch-off, producing multiple daughter drops. Notably, in both cases, the initial breakup event can trigger a cascade of subsequent breakage governed by the same underlying dynamics. Finally, analysis of the simulation data allows us to identify a scaling law for the separation distance between drops, which grows proportionally to the square of time, consistent with Batchelor scaling.

Publications related to the research:

[1] A. Roccon, F. Zonta, A. Soldati, Phase-field modeling of complex interface dynamics in dropladen turbulence, Phys. Rev. Fluids 8 (9), 090501
[2] A. Roccon, L. Enzenberger, D Zaza, A Soldati, MHIT36: A phase-field code for GPU simulations of multiphase homogeneous isotropic turbulence, Comp. Phys. Comm. 316 (109804)