Purpose This study aims to examine how pulsed electric fields govern transient Taylor cone formation and jet initiation in drop-on-demand electrohydrodynamic (EHD) printing and to identify operating conditions associated with stable droplet deposition. Design/methodology/approach A transient multiphysics finite-element model was developed and experimentally validated using synchronized high-speed imaging. The model integrated electrostatic and fluid dynamic equations with interface tracking to simulate Taylor cone formation, jet ejection and meniscus relaxation. Parametric studies systematically examined the effects of mesh resolution, applied voltage, nozzle-to-substrate distance, surface tension, viscosity, dielectric constant and ambient air conductivity. Findings Mesh refinement improved electric-field localization and temporal accuracy in predicting jet onset. Higher voltage and dielectric constant accelerated cone formation and jet elongation, while larger nozzle-to-substrate gaps enhanced jet stability but delayed initiation. Elevated surface tension and air conductivity suppressed field confinement, resulting in slower jet dynamics. Pulsed voltage operation produced discrete transient jets with controlled spacing, an approximately 4.0 µm jet diameter under the 1 ms ON/2 ms OFF condition and limited satellite formation. Originality/value This work presents a validated time-resolved EHD modeling framework that links mesh convergence, transient cone–jet stage timing, field/flow evolution and pulsed jet discreteness across electrical, geometric, fluidic and environmental operating conditions. The combined simulation–experiment approach provides quantitative design rules for optimizing cone morphology, jet stability and droplet precision, offering guidance for future development of high-resolution additive manufacturing, flexible electronics and biomedical microfabrication systems.
Usman et al. (Tue,) studied this question.