Molecular dynamics simulation of the Electrocoalescence behavior among multiple conductive droplets with varying radii

Electrocoalescence of droplets plays a critical role in various industrial processes, and multi-droplet models provide a more realistic representation of practical scenarios compared to conventional two-droplet models. However, the influence of droplet radius on the electrocoalescence behavior of multi-droplet systems and the underlying mechanisms remain unclear. In this study, molecular dynamics simulations were employed to investigate the effect of droplet radius on the electrocoalescence behavior of three droplets under a uniform direct current electric field. The impact of droplet radius was analyzed by varying the size of each droplet. The results indicate that two successive electrocoalescence events occur in the three-droplet system. When all three droplets have equal radii, an increase in droplet size leads to a reduction in both the upper and lower limits of the electric field strength required for complete electrocoalescence due to the higher number of contained ions. Moreover, the range of electric field strengths capable of inducing electrocoalescence is significantly widened, demonstrating that larger droplets are more prone to coalescence. When one droplet is larger than the others, the enhanced polarization of its surface generates more induced ions, resulting in stronger electrostatic attraction, and the larger droplet consistently coalesces first. Furthermore, in the three-droplet system, the second contact angle is always greater than the first and increases with increasing electric field strength.