Universality in the initial electrocoalescence

TL;DR

This paper identifies a universal early-time bridge growth behavior in electrocoalescence of sessile drops across various parameters, emphasizing the importance of a revised characteristic time scale that accounts for maximum deformation.

Contribution

It introduces a new universal time scale for electrocoalescence, enabling consistent comparison of coalescence dynamics across diverse conditions.

Findings

Universal early-time bridge growth observed in over twenty scenarios

Revised characteristic time scale accounts for maximum deformation

Mechanism developed to promote coalescence at contact lines

Abstract

The characteristic time for the electrocoalescence of two sessile drops is identified and verified for wide range of operating parameters such as Ohnesorge, Electrowetting number, driving frequency and drop to surrounding medium viscosity. Elegant mechanism is devised to circumvent the repulsion and promote the coalescence at the merging three phase contact lines of two electrospreading drops. With the revised definition of characteristic time scale, we demonstrated the universality of the bridge growth at the early times of coalescence for more than twenty different scenarios in triplicates. The universal bridge growth can only be obtained with the consideration of proposed time that considers the time to reach the maximum deformation in the drop, which is always ignored while defining the characteristics time scale of coalescence.