Numerical study of emulsions in homogeneous and isotropic turbulence*

We present an analysis of the effects of volume fraction, viscosity ratio and surface tension on the turbulent flow of emulsions in a tri-periodic box where Homogeneous and Isotropic Turbulence is forced at large scale. We will present integral quantities defining the flow as well as spectral scale-by-scale analysis of the energy transport through scales. Our findings reveal a significant modification of the classical energy transport occurring in single phase flows. More specifically, liquid-liquid interface offers an alternative path for energy transport towards small scales, where surface tension forces act alongside non-linear transport. We observed that this novel mechanism for energy transport scales proportionally with the total interfacial area. Furthermore, energy transfer via surface tension forces can be related to the coalescence and breakup mechanisms and, to this extent, droplet size distribution is analyzed, where we report both -10/3 and -3/2 power-law scalings for all cases. Finally, strong modulation of small scale dynamics is observed and its behavior with property variations is described.