Numerical study on coalescence behavior of suspended drop pair in viscous liquid under uniform electric field

Coalescence of drops under externally applied electric field is a significant physical process, which has been applied in many applications such as emulsion breakup, electric dehydration and raindrop formation. The morphological characteristics of two identical adjacent drops under uniform electrical strength were numerically investigated in present study. From the simulated morphologies, the behavior of the meniscus, the major axis, the minor axis, and the cone angle of coalesced drop were analyzed in details. The results indicated that drop coalescence was dependent on the electric field strength, and only below a critical threshold, coalesce occurred. Though variation might occur in lengths of the meniscus, major/minor axis, and size in cone angles, a steady state can always be reached under which electro-coalescence complete. On the other hand, drops failed to coalesce if they could not reach a steady state, and even the coalesced drop rupture due to oversized electric filed strength. Analysis of coalescence behavior of suspended drop pair in viscous liquid under uniform electric field could further promote our understanding on the physical phenomenon of electro-coalescence and provide insight for the design of the electro-coalescers in practical applications. (C) 2018 Author(s).