Characterizing binary droplet collisions of power-law fluids

Abstract

This study focuses on the dynamics of two equal-sized droplets of non-Newtonian liquids with simulations using the volume of fluid method and the local front reconstruction method. The non-Newtonian behavior is implement via a power-law model. The droplet interactions are performed for Weber numbers ranging from 20 to 300 and impact parameters from 0 to 0.6. Both methods produce similar results at low Weber numbers, while the disintegration of the droplets at high Weber numbers occurs via different mechanisms. Our results demonstrate that the boundaries of the collision maps are highly dependent on the power-law index. Additionally, the diameter of the ring for head-on collisions is increased with increasing Weber number and decreasing power-law index, while the critical ligament length in off-center collisions increases with Weber number and power-law index.