Generalizing Numerical Simulation Results for Droplet Electrodeformation Threshold Under Pulsed DC Voltage

The phenomenon of electocoalescence involves the intensification of the merging of small conductive droplets dispersed in a dielectric liquid. This phenomenon is fundamental to the crucial processes of dehydration and desalting in the oil industry. Recent studies have indicated the potential superiority of pulsed voltage over traditionally used alternating voltages at industrial frequencies and constant voltage. However, the question of the optimal parameters for pulsed voltage remains open. One challenge in determining these optimal parameters is the fact that characteristic frequencies determining droplet behavior depend on droplet size and fluids properties. The objective of this research is to generalize the frequency dependence for a critical characteristic, such as the threshold voltage for droplet rupture. We employ a numerical model based on the Arbitrary Lagrangian–Eulerian (ALE) method to generate a dataset across a wide range of droplet radii, demonstrating how dimensionless parameters can generalize the results. The study reveals that varying the droplet radius alters characteristic frequencies in a specific pattern, providing insights valuable for determining pulse parameters in experimental planning for coalescence applications.