Formalizing the effect of Initial Shape of Droplets on the Fragmentation Threshold

A Drop undergoes secondary breakup under impulsive acceleration when the initial flow Weber number is greater than its critical Weber number (We_cr). For a spherical droplet, its We_cr is a function of its density ratio (ρ), drop (Oh_d) and ambient (Oh_o) Ohnesorge numbers. Though, in nature droplets are rarely spherical and show free surface oscillations in various modes, with different modes superimposed with the fundamental mode. These initial modes depending on their initial phase can interact with the external forcing either constructively or destructively leading to significant changes in the breakup and deformation process. To illustrate these effects, droplets with different oscillation modes and magnitudes are studied using direct numerical simulations and compared against analogous spherical droplets. Significant changes to both breakup morphology and We_cr are observed.