Regimes of steady jetting in electrohydrodynamic jet printing

Electrohydrodynamic (EHD) jet printing is an additive manufacturing technique in which an electrified jet of functional ink is deposited on a motion-controlled substrate. Through experimental visualization of EHD jets, current measurements and scaling analysis, we show that steady EHD jetting can occur in three regimes: the cone-jet, moderately stretched jet, and thick-jet regimes. These EHD jetting regimes differ with respect to the relative importance of surface convection and bulk conduction currents downstream of the jet.